Combinatorial Chemistry & High Throughput Screening - Volume 10, Issue 7, 2007

The growing need for microfluidic systems in high throughput screening (HTS) urgently demands the development of compatible detection systems, especially for the analysis of non-labeled and ionizable analytes. Direct detection employing electrochemical processes offers remarkable advantages such as reduced cost, low power requirements, enhanced portability, independence of sample turbidity, subnanomolar sens Read More

This review summarizes recent progress in the development and application of solid electrodes to the screening of pharmaceutical dosage forms and biological fluids. Recent trends and advances in the electroanalytical chemistry of solid electrodes, microelectrodes and electrochemical sensors are reviewed. The varieties of solid electrodes and their basic physico-chemical properties and some specific characteristics incl Read More

The latest results of voltammetric research on the ionic transfer process of ionisable drugs across bare and lipid-modified liquid-liquid interfaces are reviewed. In recent years, two voltammetric methods have been extensively applied to this purpose, i.e. the classical four electrode voltammetry at the interface between two immiscible electrolyte solutions, and the “three-phase electrode.” Thus, a brief background o Read More

Schiff base compounds refer to the branch of supra-molecules and can be used as sensing material in the construction of potentiometric ion selective electrodes (ISEs). This relatively modern field has been subject to extensive research in the period of 1999-2007 when more than 100 ISEs employing Schiff bases were constructed. The quantitative high-throughput detection of 29 cations and 7 anions has been demonstrated Read More

Recent advances in electrochemical detection techniques coupled with high-performance liquid chromatography (HPLC-ECD) in pharmaceutical and biomedical analysis are reviewed. ECD classification and modes including common amperometric, coulometric, conductimetric, and potentiometric detector, are outlined and the some typical examples of determinations in pharmaceutical and biomedical analysis are described. The el Read More

Potentiometric sensors are studied as viable candidates for the construction of high throughput DNA arrays. For preliminary investigations, such sensors were used in an HPLC setup in the present work. This avoided errors due to ionic contaminants or additives in the commercial samples. The oligonucleotides dT10, dT20 and dT30 were used as test substances. The potentiometric sensors were of the coated wire type, containin Read More

The construction and characterization of potentiometric membrane electrodes are described for the quantification of alfuzosin, a drug used in a mono- and combined therapy of benign prostatic hyperplasia (BPH). The membranes of these electrodes consist of alfuzosin hydrochloride-tetraphenyl borate, (Az-TPB), chlorophenyl borate (Az-ClPB), and phosphotungstate (Az3-PT) ion associations as molecular recognition re Read More

The electrochemical behavior of atorvastatin calcium at glassy carbon and boron-doped diamond electrodes has been studied using voltammetric techniques. The possible mechanism of oxidation was discussed with model compounds. The dependence of the peak current and potentials on pH, concentration, scan rate and nature of the buffer were investigated for both electrodes. The oxidation of atorvastatin was irreversible a Read More

The electrochemical response characteristics of poly(vinyl)chloride (PVC) based membrane sensors for determination of tetramisole hydrochloride (TmCl) is described. The membranes of these electrodes consist of tetramisoletetraphenyl borate (Tm-TPB), chlorophenyl borate (Tm-ClPB), and phosphotungstate (Tm3-PT) ion associations dispersed in a PVC matrix with dibutylpthalate as a plasticizer. The electrodes were fully ch Read More

Polycysteic acid based electrochemical oxidation of L-cysteine (CySH) and carbon nanotubes (CNTs) formed a composite thin film material at a glassy carbon electrode (GCE) that was used a novel modifier for electroanalytical determination of sinomenine which is used for rheumatoid arthritis treatment. The determination of sinomenine at the composite modified electrode was studied by differential pulse voltammetry Read More

The PVC supported liquid membrane electrodes incorporated with undecylcalix[4]resorcinarene (UDC[4]Rene) generates a cationic potentiometric response after stimulation by neutral (unprotonated) form of diaminobenzene isomers. The potentiometric signals were generated upon the formation of supramolecular complex between the UDC[4]Rene (host) and diaminobenzene (guest) at the organic-aqueous interface. In Read More

An inexpensive, rapid and reproducible capillary electrophoretic method has been developed and validated for the determination of metformin in pharmaceutical preparations. The method was developed utilizing a fused silica capillary (60 cm x 50 μm I.D.), phosphate buffer (50 mM, 3.0 pH)-acetonitrile (95:5, v/v) as background electrolyte (BGE), 20 kV applied voltage with UV detection at 254 nm and at a working temperatur Read More

Born in Wroclaw, Poland, in 1953, Grzegorz Bazylak studied food chemistry (1974-1979) at the Technical University of Lodz (Lodz, Poland), where he also received his Ph.D. degree (1990) in technical sciences with a thesis entitled, “Studies on the association processes of amines and multidentate tricyclic Schiff base nickel(II) chelates.” Subsequently, he joined as an Adjunct Professor the Hygenics Department (1991-1997) and the I Read More