Separation of biological proteins by liquid chromatography

After the success of human genome project, proteome is a new emerging field of biochemistry as it provides the knowledge of enzymes [proteins] interactions with different body organs and medicines administrated into human body. Therefore, the study of proteomics is very important for the development of new and effective drugs to control many lethal diseases. In proteomics study, analyses of proteome is essential and significant from the pathological point of views, i.e. in several serious diseases such as cancer, Alzheimer's disease and aging, heart diseases and also for plant biology. The separation and identification of proteomics is a challenging job due to their complex structures and closely related physic-chemical behaviors. However, the recent advances in liquid chromatography make this job easy. Various kinds of liquid chromatography, along with different detectors and optimization strategies, has been discussed in this article. Besides, attempts have been made to include chirality concept in proteomics for understanding mechanism and medication of various disease controlled by different body proteins

Determination of diosmin in pharmaceutical formulations using fourier transform infrared spectrophotometry

A Fourier transform infrared [FT-IR] spectrometric method was developed for the rapid, direct measurement of diosmin in different pharmaceutical drugs. Conventional KBr- spectra were compared for best determination of active substance in commercial preparations. The Beer-Lambert law and two chemometric approaches, partial least squares [PLS] and principal component regression [PCR+] methods, were tried in data processing

Inhibition of growth of Leishmania donovani promastigotes by newly synthesized 1,3,4-thiadiazole analogs

Leishmania donovani, the causative agent of visceral leishmaniasis, is transmitted by sand flies and replicates intracellularly in their mammalian host cells. The emergence of drug-resistant strains has hampered efforts to control the spread of the disease worldwide. Forty-four 1, 3, 4-thiadiazole derivatives and related compounds were tested in vitro for possible anti-leishmanial activity against the promastigotes of L. donovani. Micromolar concentrations of these agents were used to study the inhibition of multiplication of L. donovani promastigotes. Seven compounds were identified with potential antigrowth agents of the parasite. Compound 4a was the most active at 50 micro M followed by compound 3a. These compounds could prove useful as a future alternative for the control of visceral leishmaniasis

Linear free-energy relationships in series of alkanolamines as lysosomotropic agents and choline uptake inhibitors

The solvation parameters model was used to develop a series of statistically significant linear free-energy relationship [LFER] associating lipophilicity [expressed as the logarithm of partition coefficients in n-octanol/water system, log P oct] of 25 diverse alkanolamines with their five structural descriptors constituting the general solvation parameters model proposed by Abraham [1989], as V x, the McGowan [1987] characteristic volume R 2, the excess of molar refraction [PI] H, the dipolarity/polarizability, sigma alpha H, the hydrogen-bond acidity, and sigma beta H, the effective hydrogen-bond basicity. A modified set of the fragmental constants for estimation of PI H, sigma alpha H, and sigma beta H, descriptors of individual alkanolamines has been proposed and applied to calculations of LFER by the multivariate regression procedure. Similary, LFER were established for the experimental values of logarithms of reciprocal of the minimal bactericidal concentration [log[1/MBC]] in a series of lysosomotropic alkabikanubes as reported by Sandin et al. [1992]. The calculated LFER model demonstrates that molecular size [V x term] and effective hydrogen-bond acidity [sigma alpha H term] are the most important structural parameters favouring the transport of uncharged forms of alkanolamines through the bacterial cytoplasmic membrane and their accumulation in bacterial cells. The LFER approach was also applied to experimental data relating 14 alkanolamines as the inhibitors of choline uptake into murine L1210 leukemia cells reported by Naujokaitis et al. [1984]. In this case the established LFER shows that the crucial factors which determine the inhibition of choline transport by alkanolamines are specific dispersion interactions [R 2 term], molecular size [V x term] and effective hydrogen-bond basicity [sigma beta H term] that decreases observed inhibition. The results of the studies presented indicate LFER as a suitable method for the pre-selection of the alkanolamines with defined molecular characteristics for the in vivo chemotherapy of lymphocytic leukemia

reliability of sampling process for trace atmospheric constituents

This review presents the factors required to assure the reliability of the analytical information obtained from various environmental samples, especially from air. Various factors such as the history of the sample, its homogeneity, the sampling method and their influence on the analytical process are discussed. The sampling step must be correlated to the method of analysis used for compounds to be determined as it has a main role for the reliability of the analytical process

Direct enantioseparation of drug racemates on preparative scale by hplc using various chiral stationary phases

Chirality and its influence on molecular interactions is one of the fundamentals of life itself. The understanding of chiral phenomena is therefore crucial to life sciences disciplines and to industries based on them, for example pharmaceuticals, agrochemicals and biotechnology. Due to the major differences in pharmacological activity between enantiomeric pairs, among other consideration, the widespread recognition of the importance of administering and marketing optically pure bioactive pharmaceuticals, created the steady increase and demand for efficient methods of production of chiral drugs on an industrial scale. The importance of manufacturing enantiomerically pure drugs hardly requires restatement and is becoming an essential issue for most regulatory drug agencies. With the fast development in chiral high performance liquid chromatography [HPLC] and the commercial availability of a wide range of chiral stationary phases [CSPs], large scale production of enantiomerically pure drugs becomes feasible. The advantages of applying a chromatographic process for the direct resolution of racemates on an industrial scale over the classical methods of optical resolution are:1. When the chiral stationary phase used is completely immobilized, no loss of valuable optically active materials can occur. 2. The optical purity of the material used as a stationary phase is not critical, as it affects only the separation factors obtained. 3.Recovery of eluted material can be easily automated. Various types of these CSPs currently used for this purpose is discussed along with examples of the drug racemates separated on a large scale. The potential use of chiral membranes for resolution of racemic drugs is also presented