Showing papers on "Potassium iodate published in 2008"

Determination of Arsenic in Environmental and Biological Samples Using Toluidine Blue or Safranine O by Simple Spectrophotometric Method

Abstract: A simple spectrophotometric method has been developed for the determination of arsenic in various environmental and biological samples. The method is based on the reaction of arsenic(III) with potassium iodate in acid medium to liberate iodine. This liberated iodine bleaches the blue color of toluidine blue or pinkish red color of safranine O. The decrease in absorbance at 628 or 532 nm is directly proportional to arsenic(III) concentration and obeys Beer's law in the range of 1.2-10.5 or 0.4-11.5 microg mL(-1) for arsenic(III). The molar absorptivity, Sandell's sensitivity, detection limit and quantitation limit of the method using toluidine blue or safranine O were found to be 1.076 x 10(4) or 1.388 x 10(4) L mol(-1) cm(-1), 9.66 x 10(-3) or 7.49 x 10(-3) microg cm(-2), 0.308 or 0.250 microg mL(-1), 0.934 or 0.759 microg mL(-1) respectively. The relative standard deviation for five replicate analyses of 4 microg mL(-1) of As(III) using toluidine blue or safranine O were 0.60% or 0.80%. The optimum reaction conditions and other analytical conditions were evaluated. The effect of interfering ions on the determination is described. The proposed method is free from any interference. The method has been used for the determination of arsenic in various environmental and biological samples.

Optimized and Validated Spectrophotometric Methods for the Determination of Enalapril Maleate in Commercial Dosage Forms

Abstract: Four simple, rapid and sensitive spectrophotometric methods have been proposed for the determination of enalapril maleate in pharmaceutical formulations. The first method is based on the reaction of carboxylic acid group of enalapril maleate with a mixture of potassium iodate (KIO3) and iodide (KI) to form yellow colored product in aqueous medium at 25 ± 1°C. The reaction is followed spectrophotometrically by measuring the absorbance at 352 nm. The second, third and fourth methods are based on the charge transfer complexation reaction of the drug with p-chloranilic acid (pCA) in 1, 4-dioxan-methanol medium, 2, 3-dichloro 5, 6-dicyano 1, 4-benzoquinone (DDQ) in acetonitrile-1,4 dioxane medium and iodine in acetonitrile-dichloromethane medium. Under optimized experimental conditions, Beer’s law is obeyed in the concentration ranges of 2.5–50, 20–560, 5–75 and 10–200 μg mL−1, respectively. All the methods have been applied to the determination of enalapril maleate in pharmaceutical dosage forms. Results of analysis are validated statistically.

First and novel oxidation of d-fructose by potassium iodate using [IrCl3(H2O)2OH]− complex as a homogeneous catalyst in alkaline medium

Abstract: The kinetics of Ir(III)-catalyzed oxidation of d -fructose by potassium iodate was studied in an aqueous alkaline medium at 40 °C. The experimental result shows a first order dependence on iodate and [OH−] at their low concentrations, but tending towards zeroth order at their higher concentrations. Zero order kinetics with respect to [ d -fructose] was observed throughout its variation. The linear dependence of the reaction rate at lower [Ir(III)] chloride tends towards zero order at its higher concentrations. Variation in [Cl−] and ionic strength of the medium did not bring about any significant change on the rate of reaction. The decrease in the rate of reaction with increase in the dielectric constant of the medium was observed in the oxidation of d -fructose. Kinetic and equivalence studies together with product analysis, observed effect of dielectric constant of the medium on the rate of reaction, activation parameters and multiple regression analysis furnished a basis for the formation of a common reaction mechanism for the iridium(III)-catalyzed oxidation of d -fructose by iodate in the alkaline medium.

Spectrophotometric Determination of Endosulfan Using Thionin and Methylene Blue as Chromogenic Reagents

Abstract: A simple, selective and sensitive spectrophotometric method is proposed for the determination of widely used organochlorine pesticide endosulfan using thionin and methylene blue as chromogenic reagents. The method is based on the liberation of sulfur dioxide from endosulfan by adding acid reagent and alcoholic potassium hydroxide. The liberated sulfur dioxide is passed through potassium iodate solution and the iodine so liberated bleaches the violet color of thionin and blue color of methylene blue and is measured at 600 nm and 665 nm respectively. This decrease in absorbance is directly proportional to the endosulfan concentration. The Beer’s law is obeyed in the range of 0.4–7.0 and 0.2–9.0 μg mL−1 of endosulfan using thionin and methylene blue as reagents respectively. The molar absorptivity and Sandell’s sensitivity were found to be 1.05 × 105 and 5.03 × 104 L mol−1 cm−1, 3.85 × 10−3 and 8.10 × 10−3 μg cm−2 of endosulfan using thionin and methylene blue as reagents respectively. The method has been applied for the determination of endosulfan in water, soil and vegetables.

Photocatalytic production of oxygen in a dual bed system using a reversible redox mediator on Ir-TiO2 catalyst

Abstract: Photocatalytic O2 evolution by water splitting in an alkaline solution with a redox mediator was investigated in a dual bed system configuration: one bed was used for oxygen evolution and the other for hydrogen evolution. The employed photocatalyst was Ir-TiO2 and the iodate ion, KIO3, was used as a redox mediator. In order to find the optimum conditions for oxygen evolution, the effect of alkaline concentration, KIO3 concentration and the amount of Ir loading on the photocatalytic reactivity was examined in an irradiation area of 0.055 m2 reactor with a 400 W U.V. lamp. The experimentally obtained results showed that oxygen evolution depends on the concentration of the alkaline solution, the potassium iodate concentration and the amount of Ir loading.

Iodine alginate aqua medical fertilizer and preparation method thereof

Abstract: The invention discloses an alga iodic acid aqueous medical fertilizer and a preparation method thereof. Each liter of the aqueous medical fertilizer comprises the following raw materials by mass: 20 to 30 g of alginic acid, 10 to 30 g of mannite, 8 to 72 g of potassium iodide, 1.6 to 15 g of potassium iodate, 2 to 18 g of iodine, 100 to 150 g of monopotassium phosphate, 44 to 71 g of anhydrous borax and the balance being water. The preparation method comprises the following steps: (1) the raw materials are taken out for standby according to the mass above; (2) the anhydrous borax is dissolved in water to obtain a borax liquid; (3) the alginic acid is placed in the borax liquid, is evenly mixed, is added with the mannite and the monopotassium phosphate, and is stirred and dissolved to obtain a standby liquid A; (4) the potassium iodide, the potassium iodate and the iodine are placed in the water and are dissolved to obtain a standby liquid B; and (5) the standby liquid A and the standby liquid B are evenly mixed and stirred; after stirring and precipitation, a supernatant liquid is obtained and is the alga iodic acid aqueous medical fertilizer. The alga iodic acid aqueous medical fertilizer is suitable for various crops, is safe and reliable, has no pollution, no residue and no harm, is not influenced by geographical environment and climate, can promote growth of the crop, improve adverse resistance and the like.

Thyroxin, glucose, body growth rate and non-protein nitrogen constituents in albino rats treated with excess potassium iodate

Abstract: The study was aimed to determine median lethal dose (LD50) of potassium iodate and to assess its toxicity in albino rats. The oral LD50 was found to be 752 mg kg−1 body weight. A dose of 1/5 LD50 potassium iodate was then given to animals (n = 36). Control animals (n = 36) received distilled water. Means were compared by independent-samples t-test. Growth rates of experimental animals were decreased, particularly at the first two weeks (27.5 and 24.2%, p = 0.009 and 0.000, respectively). Significant increase in serum thyroxin was observed at the second and third weeks (p = 0.007 and 0.046, respectively). Mean glucose levels were significantly decreased with maximum difference of 26.3% at the fifth week (106.1 ± 4.9 ν 78.2 ± 4.2, p = 0.002). Urea was decreased (max difference = 23.6%, mean = 35.6 ± 1.8 ν 27.2 ± 1.7, p = 0.007) whereas uric acid and creatinine were increased (max difference = 25.4%, mean = 1.77 ± 0.08 ν 2.22 ± 0.12, p = 0.011 and 19.6%, 0.56 ± 0.03 ν 0.67 ± 0.03, p = 0.022, respectively).

Determination of biochemical oxygen demand(BOD_5) in water samples by potassium iodate-starch spectrophotometry

Abstract: The biochemical oxygen demand(BOD) is an important parameter in reflecting the water quality in the environmental monitoring.The method of determining BOD5 in water by potassium iodate-starch spectrophotometry was built on the reaction between KIO3 which employed as the standard solution and excessive KI.The released I2 could react with the starch to form a blue complex,which had the maximum absorbance at 574 nm.BOD5 in water could be calculated through the amount of dissolved oxygen before and after 5 days determined.The method was used to the determination of biochemical oxygen demand in different water samples,such as BOD5 standard sample,glucose-glutamic acid solution and influent and effluent water from waste water factory and the results were in agreement with those of the national standard method.

Soy sauce containing selenium and iodine

Abstract: The invention relates to a se-i sauce which has good intestines and stomach absorption due to containing a minute of selenium and iodine. People who need to supplement the selenium and the iodine can intake the selenium and the iodine unknowingly. The advantages of the invention are that the selenium and the iodine can be supplemented with a stable dose frequently and for a long time, the effect of supplementing the selenium and the iodine is better than the supplement of the selenium and the iodine through medication without any side effects. The invention is prepared by dissolving edible sodium selenite and edible potassium iodate into ordinary sauce. The se-i sauce is prepared by dissolving the edible sodium selenite into the ordinary sauce by a mass ratio of 10-100g: 1,000,000g at 25-30 DEG C and the edible potassium iodate into the ordinary sauce by a mass ratio of 20-120g : 1,000,000g and stirring when adding, and cooling the mixture to normal temperature.

Determination of Penicillin Antibiotics by Resonance Rayleigh Scattering Method with KIO_3-KBr-Methyl Violet

Abstract: In a weak acid medium, the basic hydrolysis product of amoxicillin (AMO), ampicillin (AMP) or carbenicillin (CAR) reacted with potassium iodate to form I2, which further interacted with Br-, resulting in the formation of [I2Br]- anionic complex. Then an ion-association complex [I2Br][ MV] was formed owing to the interaction of [I2Br]- with methyl violet, which led to a significant enhancement of resonance Rayleigh scattering (RRS) and the appearance of a new RRS spectrum with the maximum wavelength at 333 nm. Under certain conditions, the intensity of RRS (ΔI) was directly proportional to the concentration of penicillin antibiotics in the range of 0.08-2.0 μg/mL. The method exhibited high sensitivity, with a detection limit of 2.3, 3.7 and 4.4 ng/mL for AMO, AMP and CAR, respectively. The reaction conditions and the influencing factors were investigated, and the effects of coexisting substances were examined. This method showed a good selectivity in this work and is, therefore, recommended for application in the determination of penicillin antibiotics in capsule and tablet pharmaceutical formulations and human serum and urine samples.

Alterações físico-química e sensorial da água potável fortificada com diferentes sais de iodo

Abstract: Seeking new alternatives to lessen the problems of Public Health due to the severity of the iodine lack in the population we want to verify the Physicalchemical and sensorial alterations of the chlorinated drinking water fortifi ed with two different iodine salts, being those iodide (KI) and potassium iodate (KIO3). In the Physical-chemical evaluation the parameters of Color, Turbidity, Conductivity and pH were used. The water added of iodine was compared to the chlorinated drinking water (0,5mg/L of chlorine) by the Triangular of Difference and Pareado Preferably tests. They were prepared solutions containing 100, 200, 300, 400, 500 μg/L of KI and 500, 1000, 2000μg/L of KIO3. The sensorial panel was formed with 30 to 52 voluntaries. The physical-chemical alterations were adapted with the values of effective reference. The Sensorial differences were observed among the chlorinated drinking water (control) and the solutions of KI in the concentrations of 500, 400 and 200μg/L, being obtained preference by the chlorinated drinking water (p < 0,05). For the solutions of KIO3 and the control, signifi cant diference was not observed. The fortifi cation of water with iodine salts doesn´t alter the physical-chemical and sensorial characteristics when it is used concentrations of inferior KI inferior to 200μg/L and inferior to 2000μg/L of iodine by the employment of KIO3