Bahram Delfan

Bio: Bahram Delfan is an academic researcher from Lorestan University. The author has contributed to research in topics: Matrix (chemical analysis) & Sorbent. The author has an hindex of 2, co-authored 3 publications receiving 18 citations.

Microextraction in a packed syringe for the analysis of olive biophenols in rat plasma using CMK-3 nanoporous sorbent.

Abstract: A carbon-based nanoporous sorbent was first used for microextraction in a packed syringe (MEPS) before HPLC/UV analysis of some biophenols in rat plasma. A laboratory-made programmable apparatus was designed and used for automation of the extraction procedure. The MEPS syringe was packed with 2 mg of CMK-3 sorbent, between the barrel and the injection needle, and mounted on an apparatus for programming of the conditioning, sampling, washing, elution and cleaning steps. All steps of the microextraction procedure were carefully optimized on the system. For optimization of important factors, such as the number of adsorption and elution cycles, elution volume and pH, a multivariate central composite design method was used. The highest recoveries were obtained for 24 and 10 times of adsorption and elution cycles, respectively, using 100 μL of acetonitrile as the eluent and a sample pH of 2. Good results were obtained in terms of the precision (RSD 1.6, 2.5 and 2.3%) and detection limit (0.7, 4.7 and 0.25 μM) for caffeic acid, tyrsol and oleuropein, respectively. The method was simple, efficient and appropriate for sample clean up before analysis by HPLC, and was successfully applied to the determination of biophenols in the plasma of several rats that received an olive leaves extract either by a gavage or an intraperitoneal injection method. A positive correlation was found between the amount of olive extract's feeding of the rats and the level of their plasma biophenols.

The Cytotoxic and Antileishmanial Effects of Satureja khuzestanica Essential Oil

Abstract: Background and Aim: Leishmaniasis is endemic in 98 countries including Iran. Pentavalent antimony compounds resistance as first-line therapy is increasing in some local areas. Also side effects of these drugs are limited at the beginning of treatment, but the toxicity increases with time. The aim of this study was to assess the effect of Satureja khuzestanica essential oil (SKEO) on promastigote and amastigote Leishmania major forms. Materials and Methods: The components of S. khuzestanica oil were identified by gas chromatography/mass spectroscopy (GC/MS) analysis. To evaluate antipromastigote activity the different concentrations of extract and glucantime were added to the wells that contained L. major . The plates were incubated at 26±1°C for a week. On days 1, 3 and 5, the number of live promastigotes in each well was counted. For assessment of SKEO effect on intracellular amastigotes, mouse peritoneal macrophages were isolated and infected with promastigotes. Different concentrations of the extract and glucantime were added to the cultures. The cultures were incubated at 37°C and CO 2 5%. The number of infected macrophages and amastigotes within each macrophage were counted. Toxicity assessment of SKEO on macrophages was done by MTT method. Results and Conclusions: The mean number of promastigotes, infected macrophages and amastigotes in a macrophage in the control and treated groups had significantly difference. So that their number in the treated groups was less as a dose-dependent response. The present research showed potent antileishmanial activity of, SKEO; additionally this plant had no toxic effect on mammalian cells.

The Efficient Extraction of Phenolic Compounds from Oak Gall Using a Miniaturized Matrix Solid-Phase Dispersion Method before their HPLC Determination

Abstract: Background and Aim: Several gall varieties are found in Lorestan Province, Iran, on Quercus infectoria oak trees, which contain important phenolic compounds. In this work, a miniaturized matrix solid-phase dispersion (MSPD) extraction method has been developed for quantitative extraction and HPLC/UV determination of them. Materials and Methods: In the MSPD method, 10 mg of sample and 50 mg of silica gel adsorbent were transferred into an agate mortar. The mixture was finely pulverized after adding 40 µL dichloromethane as disperser solvent. It was then transferred into a cartridge, eluted by 350 µL of methanol, and the eluate was subsequently injected into HPLC for analysisn. Results: The extractions were quantitative with mean recoveries of 103.0±6.8% and 99.5±7.3% for ellagic acid (EA) and gallic acid (GA) in six replicated extractions, respectively. The detection limit of the method was 0.05-0.06 mg g -1 . The method was successfully applied to the extraction and HPLC determination of the phenolic compounds in five gall species. Conclusion: The proposed technique is simple and fast. It substantially reduced the amounts of sample, sorbent and organic solvents required for the extraction. The maximum amounts of the phenolic compounds were found in Qalqaf and Bramazu galls.

Microextraction by packed sorbent (MEPS)

Abstract: Sample preparation is an important stage in separation and determination of components of interest from complex matrices. Sample preparation strongly influences the reliability and the accuracy of the analysis and the data quality. Recent trends in sample preparation include miniaturization, automation, high-throughput performance, on-line coupling with analytical instruments and low-cost operation using little or no solvent consumption. In the past decade, microextraction by packed sorbent (MEPS) was introduced as a simple, fast, on-line sample-preparation technique. Also, MEPS requires less sample and less solvent. This review gives an outline of the MEPS technique, including fields of application, common formats and sorbents, factors that affect performance, and the major advantages and limitations. Further, we offer and discuss our perspective on the future of MEPS.

Current trends on microextraction by packed sorbent - fundamentals, application fields, innovative improvements and future applications.

Abstract: MEPS, the acronym of microextraction by packed sorbent, is a simple, fast and user- and environmentally-friendly miniaturization of the popular solid-phase extraction technique (SPE). In fact, it has been widely shown that MEPS can easily replace SPE for most, if not all, previous applications. It can attain this with obvious gains in sample and solvent usage, which is greatly reduced without compromising the extraction efficiency. Furthermore, MEPS can be operated with semiautomatic electronic syringes, making it very reliable and versatile, particularly to handle very low and very high sample volumes. This review will focus on the strengths and weaknesses of this technique and the different MEPS architectures commercially available in the context of the MEPS applications reported in the last five years. Additionally, innovative improvements will be highlighted, particularly those related with new applications and recent MEPS configurations and sorbents, such as the controlled directional flow or the innovative μSPEed variant.

Microextraction using packed sorbent as an effective andhigh-throughput sample extraction technique: Recentapplications and future trends.

Abstract: In the last decade, several developments, particularly in the liquid chromatography and hyphenated techniques fields, have allowed researchers to reach analytical limits that are becoming very close to the single molecule level. Sample preparation, however, despite being a key step in the analytical methodology, did not track these developments and very few approaches able to cope with these stringent analytical requirements were developed. One such approach is microextraction by packed sorbent (MEPS), a sophisticated and miniaturized form of solid phase extraction that has reduced to the microliter scale every step of the sample extraction methodology including sample volume and solvent usage. Simultaneously, the amount of extraction phase used was also reduced and, more importantly, the sorbent is reusable dozens of times which significantly lowers the cost of analysis versus other solid-phase extraction approaches. In this review, we will update the state-of-the-art of the MEPS technique, focusing on the trends and applications reported since 2010 and future perspectives and developments that in our view will further improve the high-throughput potential and applications of this sample preparation methodology.