Showing papers in "Tropical Journal of Pharmaceutical Research in 2009"
TL;DR: In this review, this review has discussed the chemical penetration enhancement technology for transdermal drug delivery as well as the probable mechanisms of action.
Abstract: Skin as an important site of drug application for both local and systemic effects. However in skin, the stratum corneum is the main barrier for drug penetration. Penetration enhancement technology is a challenging development that would increase the number of drugs available for transdermal administration. The permeation of drug through skin can be enhanced by both chemical penetration enhancement and physical methods. In this review, we have discussed the chemical penetration enhancement technology for transdermal drug delivery as well as the probable mechanisms of action.
280 citations
TL;DR: The aim of this article is to review the development of ODTs, challenges in formulation, new ODT technologies and evaluation methodologies, suitability of drug candidates, and future prospects.
Abstract: Drug delivery systems are becoming increasingly sophisticated as pharmaceutical scientists acquire a better understanding of the physicochemical and biochemical parameters pertinent to their performance. Over the past three decades, orally disintegrating tablets (ODTs) have gained considerable attention as a preferred alternative to conventional tablets and capsules due to better patient compliance. ODTs are solid dosage forms containing medicinal substances which disintegrate rapidly, usually in a matter of seconds, when placed on the tongue. Products of ODT technologies entered the market in the 1980s, have grown steadily in demand, and their product pipelines are rapidly expanding. New ODT technologies address many pharmaceutical and patient needs, ranging from enhanced life-cycle management to convenient dosing for paediatric, geriatric, and psychiatric patients with dysphagia. This has encouraged both academia and industry to generate new orally disintegrating formulations and technological approaches in this field. The aim of this article is to review the development of ODTs, challenges in formulation, new ODT technologies and evaluation methodologies, suitability of drug candidates, and future prospects.
274 citations
TL;DR: In this article, the authors explored the phytochemistry and pharmacological activities of C. officinalis in order to collate existing information on this plant as well as highlight its multi-activity properties as a medicinal agent.
Abstract: Calendula officinalis Linn. (Asteraceae) is used medicinally in Europe, China and India amongst several places in the world. It is also known as “African marigold” and has been a subject of several chemical and pharmacological studies. It is used in traditional medicine, especially for wound healing, jaundice, blood purification, and as an antispasmodic. Chemical studies have underlined the presence of various classes of compounds, the main being triterpenoids, flavonoids, coumarines, quinones, volatile oil, carotenoids and amino acids. The extract of this plant as well as pure compounds isolated from it, have been demonstrated to possess multiple pharmacological activities such as anti-HIV, cytotoxic, antiinflammatory, hepatoprotective, spasmolytic and spasmogenic, amongst others. In this review, we have explored the phytochemistry and pharmacological activities of C. officinalis in order to collate existing information on this plant as well as highlight its multi-activity properties as a medicinal agent. This is as a result of the worldwide cultivation of the plant and increasing published reports on it.
221 citations
TL;DR: Nanotechnology is an industrial revolution based on integration of disciplines that could change every facet of human life and so these benefits should be maximized while efforts are made to reduce the risks as discussed by the authors.
Abstract: Nanotechnology in general and as it relates to drug delivery in humans has been reviewed in a two-part article, the first part of which is this paper. In this paper, nanotechnology in nature, history of nanotechnology and methods of synthesis are discussed, while also outlining its applications, benefits and risks. Nanotechnology is an industrial revolution, based on integration of disciplines that could change every facet of human life. Some examples of changes brought about by reduction in particle sizes to the physical, chemical and biological properties of substances, compounds and drug products have been cited. The benefits of nanotechnology are enormous and so these benefits should be maximized while efforts are made to reduce the risks.
132 citations
TL;DR: Some challenges associated with the technology as it relates to drug effectiveness, toxicity, stability, pharmacokinetics and drug regulatory control are discussed in this review.
Abstract: This is the second part of a review on nanotechnology in general and particularly as it pertains to drug deliver. In the earlier paper (Part 1), nanotechnology in nature, its history as well as design and methods were discussed. Its applications, benefits and risks were also outlined. In this paper (Part 2), various nanostructures employed in drug delivery, their methods of fabrication and challenges of nano drug delivery are reviewed. Nanotechnology is one approach to overcome challenges of conventional drug delivery systems based on the development and fabrication of nanostructures. Some challenges associated with the technology as it relates to drug effectiveness, toxicity, stability, pharmacokinetics and drug regulatory control are discussed in this review. Clearly, nanotechnology is a welcome development that is set to transform drug delivery and drug supply chain management, if optimally developed .
129 citations
TL;DR: The study revealed that marine actinomycetes may be a potential source of high yield, high substrate specificity L-asparaginase, which is an anti-leukaemia agent.
Abstract: Purpose: The objective of this investigation was to isolate marine actinomycetes, screen them for Lasparaginase activity and characterise the enzyme. Methods: Marine actinomycetes were isolated from sediment samples obtained from Tamilnadu and Kerala in India. The isolates were identified as actinomycetes by microscopical and biochemical tests. Production of L-asparaginase was carried out in three different media, namely, solid-state media, Tryptone Glucose Yeast extract (TGY) broth and Tryptone Fructose Yeast extract (TFY) broth.. The enzyme was purified to near homogeneity by ammonium sulphate precipitation, dialysis, gel filtration on Sephadex G-100 column and SDS-PAGE. Results: Among 10 marine isolates subjected to preliminary screening, only isolates S3, S4 and K8 showed potential for L-asparaginase activity. All three marine soil isolates synthesized asparaginase with yield ranging from 24.6 to 49.2 IU/ml. Soil isolate S3 showed the highest productivity of 49.2 IU/ml with a protein content of 65 μg/ml and optimum activity at pH 7.5 and 50 oC. The apparent Km value for the substrate was 25 μM. Mg2+ ion slightly stimulated activity while Cu2+, Zn2+ and EDTA were inhibitory. Conclusion: The study revealed that marine actinomycetes may be a potential source of high yield, high substrate specificity L-asparaginase, which is an anti-leukaemia agent.
118 citations
TL;DR: The present study provides a quantitative basis for explaining the folkloric use of L. sativum as a diuretic agent in Moroccan population by measuring urine volume, sodium and potassium content, conductivity and pH.
Abstract: Purpose : The present study was undertaken to investigate diuretic effect of aqueous and methanol extracts of the dried seeds of Lepidium sativum in normal rats. Method: Aqueous and methanol extracts of L. sativum seeds were administered to experimental rats orally at doses of 50 and 100 mg/kg p.o. Hydrochlorothiazide (10 mg/kg) was used as positive control in study. The diuretic effect of the extracts was evaluated by measuring urine volume, sodium and potassium content, conductivity and pH. Result: Urine volume was significantly increased by the two doses of aqueous and methanol extracts in comparison to control group. While the excretion of sodium was also increased by both extracts, potassium excretion was only increased by the aqueous extract at a dose of 100 mg/kg. There was no significant change in the conductivity and pH of urine after administration of the L. sativum extracts. The diuretic effect of the extracts was comparable to that of the reference standard (hydrochlorothiazide) and the methanol had the additional advantage of a potassium-conserving effect. Conclusion : We can conclude that aqueous and methanol extracts of L. sativum produced notable diuretic effect which appeared to be comparable to that produced by the reference diuretic HCTZ. The present study provides a quantitative basis for explaining the folkloric use of L. sativum as a diuretic agent in Moroccan population.
98 citations
TL;DR: The data suggest that the ethanolic root extract of C. carandas may produce its anticonvulsant effects via non-specific mechanisms since it reduced the duration of seizures produced by maximal electroshock as well as delayed the latency of seizuresproduced by pentylenetetrazole and picrotoxin.
Abstract: Purpose: The aim of the present study was to investigate anticonvulsant effect of the ethanolic extract of the roots of Carissa carandas (ERCC) on electrically and chemically induced seizures. Methods: The ethanolic extract of the roots of C. carandas (100, 200 and 400 mg/kg, i.p.) was studied for its anticonvulsant effect on maximal electroshock-induced seizures and pentylenetetrazole-, picrotoxin-, bicuculline- and N-methyl-dl-aspartic acid-induced seizures in mice. The latency of tonic convulsions and the number of animals protected from tonic convulsions were noted. Results: ERCC (100-400 mg/kg) significantly reduced the duration of seizures induced by maximal electroshock (MES). However, only 200 and 400mg/kg of the extract conferred protection (25 and 50%, respectively) on the mice. The same doses also protected animals from pentylenetetrazole-induced tonic seizures and significantly delayed the onset of tonic seizures produced by picrotoxin and N-methyl-dl-aspartic acid. The extract had no effect on bicuculline-induced seizures. Conclusion: The data suggest that the ethanolic root extract of C. carandas may produce its anticonvulsant effects via non-specific mechanisms since it reduced the duration of seizures produced by maximal electroshock as well as delayed the latency of seizures produced by pentylenetetrazole and picrotoxin.
90 citations
TL;DR: The results showed that the extract of M. morindoides has a significant antidiarrheal activity which supports its use in traditional herbal medicine practice.
Abstract: Purpose: The objective of the study was to investigate the ethyl acetate extract of Morinda morindoides (Baker) Milne-Redh (Rubiaceae) (MM-EA) properties against experimental diarrheoa induced by castor oil in albino Wistar rats. Methods: The ethyl acetate extract of Morinda morindoides (250, 500, and 1000 mg/kg body weight) was administered orally to three groups of rats (five animals per group) in order to evaluate the activity of the extract against castor oil-induced diarrhea model in rat. Two other groups received normal saline (5mg/kg) and loperamide (5mg/kg) as positive control. The effect of the extract on intestinal transit and castor oil-induced intestinal fluid accumulation (enteropooling) was assessed. Results : At oral doses of 250, 500, and 1000 mg/kg body weight, the plant extract showed pronounced and dose-dependent antidiarrheal activity. The protective role of the extract at 1000 mg/kg was comparable to that of the reference drug, loperamide (5mg/kg). The extract (1000 mg/kg) produced a decrease in intestinal transit comparable to atropine (5mg/kg), and significantly (p<0.01) inhibited castor oil-induced enteropooling. No mortality and visible signs of general weakness were observed in the rats following the extract administration of up to a dose of 6000 mg/kg. Conclusion: The results showed that the extract of M. morindoides has a significant antidiarrheal activity which supports its use in traditional herbal medicine practice.
89 citations
TL;DR: In this paper, the effect of chitosan molecular weight on size, size distribution, release rate, muco-adhesive properties and electrostatic bonding of alginate/chitosans microparticles containing prednisolone was investigated.
Abstract: Purpose : The aim of the present study was to investigate the effect of chitosan molecular weight on size, size distribution, release rate, mucoadhesive properties and electrostatic bonding of alginate/chitosan microparticles containing prednisolone Method s: Three mucoadhesive alginate/chitosan microparticle formulations, f1, f2 and f3, were prepared using low, medium and high chitosan molecular weight (MW) chitosan, respectively, by directly spraying alginate solution into a solution of chitosan and calcium chloride at optimum conditions. Prednisolone was incorporated in the alginate solution prior to spraying. The microparticles were then evaluated for prednisolone content, size, release rate, and mucoadhesive properties using appropriate methods. The formation of electrostatic and hydrogen bonds between chitosan and alginate was assessed by differential scanning calorimetetry (DSC) and Fourier transform infrared (FTIR). Results : The results indicate that high MW chitosan microparticles were significantly (p<0.05) smaller and more uniform in size, with better mucoadhesive properties and lower release rate than the other formulations. FTIR and DSC studies indicate that stronger hydrogen and electrostatic bonding in the formulation containing high MW chitosan than inthe other formulations Conclusion : The physicochemical properties of chitosan-alginate microparticles are dependent on the molecular weight of chitosan
68 citations
TL;DR: It is demonstrated that Sukun wood extract induced apoptosis and sub-G1 phase formation in breast cancer (T47D) cells, and therefore, has a potential as an anti-cancer agent.
Abstract: Purpose: To evaluate the anti-cancer properties of the diethylether extract of Sukun (Artocarpus altilis) wood. Methods: The extract was tested in human T47D breast cancer cells and examined for its effect on cell viability, nuclear morphology and sub-G1 formation. Cell viability was determined by microculture tetrazolium technique (MTT), nuclear morphology investigated using 4’-6-diamidino-2-phenylindole (DAPI) staining technique, and cell cycle progression monitored by sub-G1 apoptosis assay using flow cytometry. Results: The results showed decreasing cell viability in a concentration-dependent manner. Altered cell morphology after treatment with the extract demonstrated that cells experienced apoptosis. Cell cycle analysis indicated that the number of cells in sub-G1 phase rose with increasing concentrations of the extract. Conclusion: The data demonstrate that Sukun wood extract induced apoptosis and sub-G1 phase formation in breast cancer (T47D) cells, and therefore, has a potential as an anti-cancer agent.
TL;DR: In this paper, a solid dispersion of furosemide in sodium starch glycolate (SSG) by kneading method was used to improve the dissolution properties of the drug.
Abstract: Purpose: This investigation was carried out to determine if a solid dispersion of furosemide in sodium starch glycolate (SSG) would enhance the dissolution properties of the drug. Methods: Solid dispersion of furosemide in SSG was prepared in ratios of 1:1 and 1 (furosemide):2 (SSG) by kneading method. In each case, the solid dispersion was characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) to ascertain if there were any physicochemical interactions between drug and carrier that could affect dissolution. Tablets containing the solid dispersion were formulated and their dissolution characteristics compared with commercial furosemide tablets. The dissolution studies were performed at 37 ± 0.5 o C and 50 rpm in simulated gastric fluid (pH 1.2). Results: FTIR spectroscopy, DSC, and XRD showed a change in crystal structure toward an amorphous form of furosemide. Dissolution data indicated that furosemide dissolution was enhanced. XRD, DSC, FTIR spectroscopy and dissolution studies indicated that the solid dispersion formulated in 1:2 ratio showed a 5.40-fold increase in dissolution and also exhibited superior dissolution characteristics to commercial furosemide tablets. Conclusion: Solid dispersion technique can be used to improve the dissolution of furosemide.
TL;DR: Among these, Terminalia chebula Retz.
Abstract: Purpose: To evaluate the anti-enterobacterial potential of nine ethnobotanically selected plants traditionally used in different parts of India for the treatment of gastrointestinal disorders such as cholera, diarrhea or dysentery. Methods: The methanol extracts of these plants were screened for antibacterial activity against 11 strains of enteropathogenic bacteria, including multi-drug resistant Vibrio cholerae (serotypes O1, O139, and non-O1, non-O139), using broth microdilution method. Ampicillin was used as a positive reference standard to determine the sensitivity of the strains. Phytochemical screening was carried out for phenolics and flavonoids. Results: All of these plants had bactericidal activity against at least one of the test microorganisms with minimum inhibitory concentration (MIC) ranging from 0.125 to 32 mg/ml and minimum bactericidal concentration (MBC) ranging from 0.25 to 32 mg/ml. Among these, Terminalia chebula Retz. (Combretaceae ) and Syzygium cumini (L.) Skeels (Myrtaceae) showed the most promising broad spectrum antibacterial properties, inhibiting all of the strains tested, especially Vibrio cholerae, Aeromonas hydrophila and Bacillus subtilis, with MBC ranging from 0.25 to 4 mg/ml. Phenolics and flavonoids were found to be present in the extracts. Conclusion: The findings provide support for the use of this plant in traditional medicine for treatment of diarrheoa, especially cholera.
TL;DR: The study suggests that crosslinked chitosan film containing ciprofloxacin and diclofenac is a potential drug delivery device for the topical treatment of periodontitis.
Abstract: Purpose: This study was designed to develop and evaluate chitosan films containing ciprofloxacin and diclofenac sodium for the topical treatment of periodontitis. Methods: Chitosan films containing ciprofloxacin alone and in combination with diclofenac sodium were prepared by solvent casting method. Some of the drug-loaded films were crosslinked with 2% gluteraldehyde for 2 and 4 h, respectively. The films were then evaluated for their physicochemical properties including weight variation, thickness, tensile strength, in vitro release, stability and antibacterial activity. Results: Mean weight and thickness data showed that the different films were uniform. Tensile strength was maximum for drug-free films and minimum for films containing the highest amount of drug(s). In vitro drug release data indicate that the films showed an initial burst release followed by sustained release of the drug(s). Films stored at refrigerated conditions exhibited slower degradation rate. The drug-loaded films that were crosslinked for 4 h had inhibitory effect on Staph mutans for up to 24 days. Conclusion: The study suggests that crosslinked chitosan film containing ciprofloxacin and diclofenac is a potential drug delivery device for the topical treatment of periodontitis. Good physicochemical properties were shown by the films.
TL;DR: Chloroform and alcoholic extracts of H. spinosa leaves have anti-inflammatory and antipyretic activities and reduced elevated body temperature in rats at 200 and 400 mg/kg body weight doses throughout the observation period of 6 h.
Abstract: Purpose: Hygrophila spinosa T. Anders (Acanthaceae) is commonly used in the traditional system of medicine for the treatment of inflammation, pain, jaundice, rheumatism, arthritis, anaemia, etc. In the present study, we investigated the anti-inflammatory and antipyretic activities of the petroleum ether, chloroform, alcoholic and aqueous extracts of the leaf of this plant. Methods: The anti-inflammatory activity of the various extracts was studied based on their effects on carrageenan-induced paw oedema in rats while antipyretic activity was evaluated on the basis of their effect on Brewer’s yeast-induced pyrexia in rats. The extracts were screened for alkaloids, steroids, proteins, flavonoids, saponins, mucilage, carbohydrates, organic acids, fats and oils. Results: Preliminary phytochemical screening revealed the presence of alkaloids, steroids, proteins, flavonoids, fats and oils, tannins, mucilage and organic acids in the leaves of H. spinosa. Chloroform and alcoholic extracts of leaves of H. spinosa produced significant (p < 0.05 and p < 0.01) anti-inflammatory and antipyretic activities in a dose-dependent manner. On the other hand, petroleum ether and aqueous extracts did not show significant anti-inflammatory and antipyretic activities. The maximum anti-inflammatory activities produced by chloroform and alcoholic extracts (400 mg/kg) were 33.7% and 47.5%, respectively. These two extracts also reduced elevated body temperature in rats at 200 and 400 mg/kg body weight doses throughout the observation period of 6 h. Conclusion: Chloroform and alcoholic extracts of H. spinosa leaves have anti-inflammatory and antipyretic activities.
TL;DR: The present investigation suggests that Clitoria ternatea leaf and flower extracts exhibit antihyperglycaemic effect in rats with alloxan-induced diabetes mellitus.
Abstract: Purpose: This study aims to investigate the therapeutic effects of the aqueous extract of Clitoria ternatea Linn. Fabaceae leaves and flowers on alloxan-induced diabetes in rats. Methods: The effect of orally administered aqueous extracts (400 mg/kg body weight) of Clitoria ternatea leaves and flowers on serum glucose, glycosylated hemoglobin, and insulin were examined in control and extract-treated diabetic rats. The glycogen content of the liver and skeletal muscles of the rats was evaluated while the activities of the glycolytic enzyme, glucokinase, and the gluconeogenic enzyme, glucose-6-phosphatase in the liver were assessed. The extracts were administered over a period of 84 days. Results: The aqueous extracts of Clitoria ternatea leaves and flowers significantly (P<0.05) reduced serum glucose, glycosylated hemoglobin and the activities of gluconeogenic enzyme, glucose-6phosphatase, but increased serum insulin, liver and skeletal muscle glycogen and the activity of the glycolytic enzyme, glucokinase. For all the biochemical tests performed, the leaf extract-treated rat showed essentially the same profile as those treated with the flower extract. Conclusion: The present investigation suggests that Clitoria ternatea leaf and flower extracts exhibit antihyperglycaemic effect in rats with alloxan-induced diabetes mellitus.
TL;DR: Variations both in a disease state and in drug plasma concentration need to be taken into consideration in developing drug delivery systems intended for the treatment of disease with adequate dose at appropriate time.
Abstract: Chronotherapeutics refers to a treatment method in which in vivo drug availability is timed to match rhythms of disease, in order to optimise therapeutic outcomes and minimise side effects. It is based on the observation that there is an interdependent relationship between peak-to-trough rhythmic activity in disease symptoms and risk factors, pharmacologic sensitivity, and pharmacokinetics of many drugs. The specific time that patients take their medication is very important as it has significant impact on treatment success. Optimal clinical outcome cannot be achieved if drug plasma concentrations are constant. If symptoms of a disease display circadian variation, drug release should also vary over time. Drug pharmacokinetics can also be time-dependent; therefore, variations both in a disease state and in drug plasma concentration need to be taken into consideration in developing drug delivery systems intended for the treatment of disease with adequate dose at appropriate time. Various technologies such as time-controlled, pulsed, triggered and programmed drug delivery devices have been developed and extensively studied in recent years for chronopharmaceutical drug delivery. These, as well as pertinent issues, are addressed in this review.
TL;DR: The formulations developed could potentially be used for controlled delivery of highly soluble drugs such as diltiazem HCl, and incorporation of EC in tablets with HPMC as the matrix was found to control drug release.
Abstract: Purpose: To develop a oral controlled matrix drug delivery system for a highly water soluble drug, diltiazem HCl, and investigate its drug release mechanism. Method: Diltiazem HCl was chosen because of its high water solubility. Tablets containing the drug were prepared by direct compression method using different matrix ratios of ethyl cellulose (EC) and hydroxypropyl methylcellulose (HPMC). The formulations were evaluated in vitro for their dissolution characteristics over a period of 8 h. Drug release was analysed according to various release kinetic models. Results: The results showed that these polymers slowed down the release of diltiazem HCl from the matrices. In the presence of EC, increasing the concentration of HPMC decreased the release rate of diltiazem. Furthermore, incorporation of EC in tablets with HPMC as the matrix was found to control drug release. Kinetic analysis showed that drug release from three of the formulations was adequately described by zero order model. Conclusion: The formulations developed could potentially be used for controlled delivery of highly soluble drugs such as diltiazem HCl.
TL;DR: The data indicate that P. crocatum methanol extract inhibits the growth of human breast cancer (T47D) cells via inhibition of p44/p42 phosphorylation.
Abstract: Purpose: To investigate the anti-cancer properties of the methanol extract of Piper crocatum Ruiz & Pav. leaves and its mode of action in human breast cancer (T47D) cells. Methods: The anti-cancer property and mechanism of action of the extract were evaluated by its effect on cell viability, nuclear morphology, cell cycle progression and the expression of phosphorylated p44/p42 as a marker for cell proliferation. Results: The results showed that there was a reduction of cell viability by the extract in a concentrationdependent manner and no alteration of nuclear morphology was observed. There were negligible changes in Sub-G1 phase formation after extract treatment. Expression of phosphorylated p44/42 was decreased by the extract only. Inclusion of the extract in the incubation medium decreased insulinstimulated phosphorylation of p44/p42 indicating that the anti-proliferative effect of the extract was via p44/p42 pathway. Conclusion: All together, the data indicate that P. crocatum methanol extract inhibits the growth of human breast cancer (T47D) cells via inhibition of p44/p42 phosphorylation.
TL;DR: NM possesses protected rats against hyperglycaemia, hyperlipidaemia and cardiac tissue damage following MI, and should be further investigated as a prophylactic against the risk of MI.
Abstract: Purpose: The present study was designed to evaluate the hypoglycaemic and hypolipidaemic activities of the aqueous extract of nutmeg (i.e., the kernel of Myristica fragrans) in rat models against myocardial infarction (MI) induced by isoproterenol (ISO). Methods: Rats were pretreated with nutmeg extract (NM) at an oral dose of 100 mg/kg/day for a period of 30 days, followed by the induction of MI by subcutaneous administration of ISO (85 mg/kg) for two consecutive days. The heart tissue was excised immediately, washed with chilled isotonic saline and used in histopathological studies. Blood was also collected from the animals and the plasma separated was subjected to biochemical analysis. Results: In ISO-administered group, a significant (p < 0.05) increase in the levels of blood glucose, plasma lipids and lipoprotein lipase activity was observed along with hyalinization of muscle fibres, compared NM-pretreated ISO-administered rats. In rats treated with NM, biochemical parameters were near normal. Histological studies revealed reduced damage of heart tissue in ISO-administered rats that were pretreated with NM. Conclusion: NM possesses protected rats against hyperglycaemia, hyperlipidaemia and cardiac tissue damage following MI. Therefore, NM should be further investigated as a prophylactic against the risk of MI.
TL;DR: The results from this study indicate the need for further research into the possible value of toothpaste for reducing oral bacterial flora.
Abstract: Purpose: To assess the microbial quality as well as the effectiveness of seven brands of toothpaste marketed in Abuja, Nigeria’s capital city, for reducing oral bacterial flora. Methods: Seven brands of toothpaste were randomly purchased from the open market in Abuja. Two brands contained triclosan + sodium fluoride as antibacterial, four contained sodium fluoride only and one was herbal. Each of the toothpaste products was assessed in duplicate for microbial safety based on growth on nutrient agar and broth. Also, eight volunteers were enrolled who used a toothpaste brand 12hourly on three consecutive occasions as the only source of oral hygiene, and then switched over to another brand. Mouth swaps and saliva before and after brushing was taken, plated by the pour plate technique, incubated at 37uC and then counted on nutrient agar after 24 h. Percentage bacterial reduction was calculated from the difference in bacterial counts before and after brushing. Results: All the toothpaste brands were sterile. 71% of the toothpaste brands were found to significantly (p=0.068) increase saliva bacteria counts. No brand of toothpaste removed teeth bacteria by up to 50%. On average, the two triclosan-containing toothpaste brands exerted a greater reduction in mouth bacteria than non-triclosan toothpaste brands. This was followed by the herbal toothpaste. The toothpaste brands that contained only fluoride were the least effective in reducing mouth bacteria. Conclusion: The results from our study indicate the need for further research into the possible value of toothpaste for reducing oral bacterial flora.
TL;DR: Although nimodipine-loaded alginate beads showed poor sustained release characteristics, modification with chitosan yielded beads that exhibited sustained drug release.
Abstract: Purpose: The aim of this work was to prepare nimodipine-loaded alginate-chitosan beads for sustained drug release. Methods: Nimodipine-loaded alginate-chitosan beads were prepared by ionic gelation method using various combinations of chitosan and Ca 2+ as cations and alginate as anion. The swelling ability and in vitro drug release characteristics of the beads were studied at pH 1.2 and 6.8. Infra-red (IR) spectrometry, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), x-ray diffraction (XRD), and atomic absorption spectroscopy (AAS) were also applied to investigate the physicochemical characteristics of the drug in bead formulations. Results: The surface morphology, size, and drug loading of the beads varied with increase in the concentration of chitosan and calcium chloride in the gelation medium. The swelling ability of the beads in different pH media was dependent on the presence of a polyelectrolyte complex in the beads and the pH of the media. Both calcium alginate beads and the beads treated with chitosan failed to release the drug at pH 1.2 over the period of study. On the other hand, at pH 6.8, calcium alginate beads released approx. 96 % of drug in 6 h, but treatment of the beads with chitosan lowered drug release to 73 %. Drug release mechanism was either “anomalous transport” or “case-II transport”. Data from characterisation studies indicate that there was no significant change in the physical state of the drug in the bead formulations. Conclusion: Although nimodipine-loaded alginate beads showed poor sustained release characteristics, modification with chitosan yielded beads that exhibited sustained drug release.
TL;DR: In this paper, the effect of Eudragit RS PO and RL PO polymers on the physical property and release characteristics of carbamazepine matrix tablets was evaluated for hardness and release.
Abstract: Purpose: The objective of this research work was to prepare and evaluate the effect of Eudragit RS PO and Eudragit RL PO polymers on the physical property and release characteristics of carbamazepine matrix tablets. Methods: Matrix tablets containing carbamazepine were prepared with Eudragit® RS PO alone as the rate-retarding polymer (coded batch series ‘A’) and also with a combination of Eudragit® RS PO and RL PO (coded batch series ‘B’). The tablets were characterized for hardness as well as for carbamazepine release. The release data were subjected to different models in order to evaluate their release kinetics and mechanisms. Results: The hardness of batch series ‘A’ matrix tablet was >160 kg/cm2 while for batch series ‘B’, it was >170 kg/cm2. Carbamazepine tablets containing only Eudragit RS PO showed very slow release (less than 6% in 8 h) but when Eudragit RL PO was blended with Eudragit RS PO, the release rate improved significantly to 44% in 24 h (p Conclusion: Carbamazepine matrix tablets of satisfactory hardness were produced. Furthermore, by blending Eudragit RS PO with Eudragit RL PO in the matrix, tablets of varying release characteristics can be prepared.
TL;DR: In this article, the authors compared gliclazide solid dispersions (SDs) with polyethylene glycol (PEG) 8000 and compared them with SDs in PEG 6000.
Abstract: Purpose : The aim of the present study was to characterise gliclazide solid dispersions (SDs) prepared with polyethylene glycol (PEG) 8000 and compare them with SDs in PEG 6000. Methods : Gliclazide SDs containing varying concentrations of PEG 8000 were prepared using the fusion – solvent technique, and their phase solubility behavior and dissolution in 0.1N HCl were assessed at 37 o C. The physical state of, and gliclazide-PEG interactions in, SDs and physical mixtures prepared in ratios of 1:1, 1:2 and 1:5 (gliclazide: PEG 8000), respectively, were characterized by x-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). Results : The solubility of gliclazide increased with increasing amount of PEG 8000 in aqueous medium. Gibbs free energy ( �G o tr ) values were all negative, indicating the spontaneous nature of gliclazide solubilisation. Dissolution studies indicated a significant increase in the dissolution of gliclazide when dispersed in PEG 8000. FTIR analysis demonstrated the absence of well-defined gliclazide - PEG 8000 chemical interaction while DSC and XRD studies indicated the amorphous /microcrystalline state of gliclazide in the SDs. Conclusion : In both solid dispersions and physical mixture, PEG 8000 increases the solubility and dissolution rate of gliclazide. The increased dissolution rate of gliclazide may be due to the formation of microcrystals, increased wettability and dispersibility in systems containing PEG 8000.
TL;DR: The aqueous fruit pulp extract of Hunteria umbellata K. Schum possesses antipyretic and analgesic activities which validate its use in the treatment of pains and fevers.
Abstract: Purpose: The aqueous fruit pulp extract of Hunteria umbellata K. Schum is used traditionally for the treatment of various fevers. The purpose of this study was to evaluate the extract for antipyretic and analgesic activity, and determine its probable mechanism of action. Methods: Pyrexia was induced in rabbits by intravenous injection of 105 CFU of E. coli/kg. Rectal temperature was monitored at 30, 60, and 90 min post-administration of 250 and 500 mg/kg of the extract. The analgesic effect of the extract was evaluated using acetic acid-induced mouse writhing test. The extract was tested for antimicrobial activity against Staphylococcus aureus, Klebsiella pnuemoniae, Escherichia coli, and Psuedomonas aeruginosa using agar diffusion method. Phytochemical screening of the plant extract was also carried out. Results: Phytochemical screening revealed the presence of simple sugars, saponins, flavonoids, alkaloids and steroidal compounds. The extract (250, 500 mg/kg) and aspirin produced comparable antipyretic effects up to 60 min. The extract did not inhibit the growth of the microorganisms but significantly reduced the number of writhes in mice at 250 and 500 mg/kg with results comparable to ASA. Conclusion: The extract possesses antipyretic and analgesic activities which validate its use in the treatment of pains and fevers.
TL;DR: In this paper, the authors developed a validated, rapid, simple and economic stability indicating reverse phase HPLC method for estimating meloxicam (MLX) in bulk and commercial preparations.
Abstract: Purpose: The present study was undertaken to develop a validated, rapid, simple and economic stability indicating reverse phase HPLC method for estimating meloxicam (MLX) in bulk and commercial preparations. Method: Reversed phase chromatographic analysis was performed on a C18 Hi Q Sil column with acetonitrile-water-glacial acetic acid [55:40:5 (% v/v)] at a flow rate of 1ml/min and detection wavelength of 355 nm. System suitability tests essential for the assurance of quality performance of the method were performed. The drug was subjected to stress degradation studies under acidic, basic and oxidative conditions. The method was validated for accuracy, precision, reproducibility, specificity, robustness, limit of detection (LOD) and limit of quantification (LOQ) , as per International Conference on Harmonization (ICH) guidelines. Results: A single sharp peak was obtained for MLX at Rt of 6.8 ± 0.01min. The polynomial regression data for the calibration plots exhibited good linear relationship (r = 0.9995) over a concentration range of 4–20 μg/ml and the linear regression equation was y = 57257.38x + 3443.07. Accuracy ranged from 99.27 to 100.78% and the % coefficient of variation (CV) for both intra-day and inter-day precision was less than 2%. MLX showed minor degradation peak in acidic conditions at Rt of 2.24min. The LOD and LOQ values were 360 ng/ml and 510 ng/ml, respectively. Conclusion: The proposed method gave good resolution of MLX and its degradants. System suitability tests and statistical analysis performed prove that the method is precise, accurate and reproducible, and hence can be employed for routine analysis of MLX in bulk and commercial formulations.
TL;DR: The chemical composition and insecticidal activity of the essential oil of the plant leaf was established and possible mechanism of action may lead to the development of a potential insecticidal product.
Abstract: Purpose: Insecticides have been known to cause serious toxicological and environmental problems. Hence, the insecticidal activity and chemical composition of a local medicinal plant was investigated. Methods: Steam distillation of P.staudtii leaves was carried out using a Clavenger apparatus in order to obtain the volatile oils. Gas chromatography/mass spectrometric (GC/MS) analyses ( DB-5 Optima-5 column) of the essential oil were performed and its insecticidal activity determined. Results: GC-MS spectrometry showed that the major chemical components of the oil were tetradecanoic acid (22 %), hexanoic acid, �-phellandrene (13 %), and citronellol sp. (7 %). The work also revealed significant insecticidal activity of 80 % and 60 % against Rhyzopertha dominica and Tribolium castaneum, respectively. Conclusion : The study established the chemical composition and insecticidal activity of the essential oil of the plant leaf. Future formulation studies, toxicity profile and possible mechanism of action may lead to the development of a potential insecticidal product.
TL;DR: In this article, a 2 2 factorial design was used to investigate the amount of crospovidone and taste masking, soothening hydrophilic agent (mannitol), and disintegration time as dependent response.
Abstract: Purpose: The objective of this study was to formulate and optimize an orodispersible formulation of meloxicam using a 2 2 factorial design for enhanced bioavailability. Methods: The tablets were made by non-aqueous wet granulation using crospovidone and mannitol. A 2 2 factorial design was used to investigate the amount of crospovidone and taste masking, soothening hydrophilic agent (mannitol), as independent variables, and disintegration time as dependent response. Formulated orodispersible tablets were evaluated for weight variation, friability, disintegration time, drug content, wetting time, water absorption ratio and in vitro drug release. Results: The results show that the presence of a superdisintegrant and mannitol is desirable for orodispersion. All the formulations satisfied the limits of orodispersion with a dispersion time of less than 60 sec. For example, formulation F 4 showed a disintegration time of 32.1 sec, crushing strength of 4.93 kg/cm 2 , drug content of 98.5% and fast drug release rate of 99.5% within 30 min, as compared with the conventional tablet (49.5%) . Conclusion: It is feasible to formulate orodispersible tablets of meloxican with acceptable disintegration time, rapid drug release and good hardness, which could be amenable to replication on an industrial scale.
TL;DR: The QNS products available in the Dar es Salaam market were of good microbial quality, however, WFI products were microbiologically contaminated, and regulatory authorities in Tanzania should diligently enforce regulatory control of the products to assure consumer safety.
Abstract: Purpose : To conduct microbiological assessment of commercially available quinine syrups and water for injection in Dar es Salaam, Tanzania. Methods : This was a cross-sectional study conducted in Dar es Salaam Region. Samples of quinine syrups (QNSs) and water for injection (WFI) of different batches were randomly purchased. Each QNS was inspected for label disclosure, and physicochemical properties were examined by the use of sense of organs and pH meter. Isolation and quantification of microbial contaminants from each sample was preceded by 24 - 48 h incubation at 37 oC, and the microbial contaminants were expressed as colony forming unit per millilitre (cfu/ml). Microbiological identification of contaminants was performed by examination of colony morphologies and growth characteristics. Gram staining technique, as well as biochemical and serological tests were also conducted for further identification. Albino rabbits were used for the pyrogen test to determine the presence of microbial contamination in WFI. Results: Twenty-four samples of QNS underwent label disclosure, physical-chemical and microbiological assessments. All QNS samples complied with the guidelines and microbial limits as per United States Pharmacopoeia (USP). All batches of WFI were found to be microbiologically contaminated, revealing average microbial counts of 87, 94 and 100 cfu/ml, and this was buttressed by pyrogen test, with the animals showing temperature rise of 1.0, 2.2 and 2.4 oC, respectively. Conclusion: The QNS products available in the Dar es Salaam market were of good microbial quality. However, WFI products were microbiologically contaminated. We recommend that regulatory authorities in Tanzania should diligently enforce regulatory control of the products to assure consumer safety.
TL;DR: The results confirmed that the factors responsible for drug release were osmotic agents (core) and pore former (membrane) and the preparation of swellable controlled porosity osmosis pump tablet was facilitated by coating the core tablet with pore forming agent, thus eliminating the need for the more expensive laser drilling.
Abstract: Purpose: To develop swellable controlled porosity osmotic pump tablet of theophylline and to define the formulation and process variables responsible for drug release by applying statistical optimization technique. Methods: Formulations were prepared based on Taguchi Orthogonal Array design and Fraction Factorial design for core and coating, respectively. The tablets were prepared by direct compression and wet granulation methods; spray coated with ethyl cellulose solution containing varying amounts of PEG 400 and plasdone. Drug release from the osmotic drug delivery system was studied using USP Type I paddle type apparatus. The membrane morphology of the delivery system was determined by scanning electron microscopy (SEM). Results: Optimization results indicated that the release rate of theophylline from the swellable controlled porosity osmotic pump tablet is directly proportional to the levels of osmotic agent, solubilizing agent and pore former in the tablet core and the membrane, respectively. SEM showed the formation of pores in the membrane through which drug release occurred. The best formulation showed 98.2 % drug release and complied with USP requirements. Conclusion : The results confirmed that the factors responsible for drug release were osmotic agents (core) and pore former (membrane). Also, the preparation of swellable controlled porosity osmotic pump tablet was facilitated by coating the core tablet with pore forming agent, thus eliminating the need for the more expensive laser drilling.