Overview of Pharmaceutical Analysis: Determination and monitoring of drugs and endogenous compounds in pharmaceuticals solutions and biological fluids, improvement of drugs' physicochemical properties such as increasing their solubility, studying chemical stability of drugs and determination of trace amounts of inorganic elements in biological fluids and other matrices are the main research areas in this lab. By using different analytical instruments like spectrophotometer, spectrofluorometer, chromatography, capillary zone electrophoresis and atomic absorption spectrophotometer, it is possible to achieve above purposes. Most of the projects are defined based on pure research purposes, however any request from the industry dealing with our subjects are most welcomed. The most potential areas are the pharmaceutical analyses, drug crystallization and purification processes and quality control of pharmaceutical products. The main research topics that are investigated in the pharmaceutical analysis laboratory are as follows: Solubility of drugs is one of the most important physico-chemical properties. The use of solvent mixtures to enhance the solubility is a very common method in practice and a trial and error approach has been used to optimize the mixed solvent composition so far. Modeling solubility data in mixed solvents enables the researchers to speed up the drug formulation process in preformulation studies. The Jouyban-Acree model has been developed in the lab and improved the accuracy of the solubility prediction methods at least by a factor of 2. The research is onging in this field and our lab is one of the most active in the area around the world. The capability of the Jouyban-Acree model was also extended to represent the solubility and also a number of physico-chemical properties in mixed solvents at various temperatures. Capillary electrophoresis is a new and fast growing analytical technique for analysis of pharmaceuticals, and prediction of electrophoretic mobility of the analytes using computational methods will help an analyst to find the best separation conditions using a minimum number of experiments. This will speed up the method development process in capillary electrophoresis studies. In addition to the application of the Jouyban-Acree model for calculating the electrophoretic mobility data in capillary electrophoresis, quantitative structure-property relationships were developed to represent the electrophoretic mobility and also retention factors in capillary electrophoresis and micellar electrokinetic chromatography. - Prediction of drug solubility in supercritical fluids:
Employing supercritical fluids in the pharmaceutical industry is a new application for this technology. Its main applications in pharmaceutics are producing micro fine particles with specified size, extraction of compounds from natural and synthetic sources and preparing drug loaded microparticles. Solubility data in supercritical fluids is required to design any industrial technique, and data collection by experiments are time consuming and costly. By providing computational methods to predict solubility data in supercritical fluids, a researcher is able to save time and money in developing such a technology. - Determination of endogenous compounds and drugs:
Some part of studies carried out in this laboratory is related to the determination and monitoring of biological levels of drugs and endogenous compounds using chromatographic and capillary electrophoretic methods. With respect to this area, several projects are currently under investigation. Routine analysis of antiepileptic drugs in serum/plasma is carried out in the lab and efforts are devoted to replace biological samples other than blood, serum or plasma for therapeutic drug monitoring. The main focus is on the replacement of saliva sample to monitor antiepileptic drugs using micellar electrokinetic chromatography which reduces the required sample volume to the microliter levels. - Bioequivalent and chemical stability studies of drugs:
In order to improve the quality, Iranian pharmaceutical industries require some bilateral studies with universities for the control and evaluation of their products and formulation of new dosage forms. Therefore, some of the studies performed in the instrumental laboratory concern with the bioequivalent and chemical stability studies of drugs which are carried out in joint with pharmaceutical technology and pharmacology laboratories. Any request from the pharmaceutical industry is most welcomed in this field. Lanthanide ions have weak fluorescence emission, so some organic ligands are used to improve their fluorescence intensity. The main advantages of these chalates in spectrofluorometry including large stock shifts, narrow emission bands and long fluorescence life times enable them to be used in pharmaceutical analysis in which a complex could be formed between lanthanide ions and the drug molecules. |