Page - (000093) - in Biomedical Chemistry: Current Trends and Developments

Transfected MDCK cell line MDCK are previously transfected with P- glycoprotein gene to over- express the transporter. 5 days of incubation is usually required to initiate the studies. Bi-directional studies and compound quantification by HPLC with simple sample preparation for bioanalysis. Determination of efflux coefficient. Evaluate the efflux transport via P-glycoprotein. Identification of P- glycoprotein substrates and inhibitors in drug discovery. Evaluation of drug-drug interaction potential. Membrane vesicles Membrane vesicles prepared from organs (such as liver, kidney and intestine) that naturally express high concentrations of transporters or from transfected cell lines (such as MDCK) that over- express a single transporter. This technique allows separate preparations of the blood side of cell membranes (liver- sinusoidal, kidney and intestine basolateral) and luminal side of cell membranes (liver-bile canalicular, the intestine and kidney-brush-border). Assess the transporter mechanisms in liver, kidney and intestine. Protein binding in vitro models Ultrafiltration A semi-permeable membrane separates an upper chamber where drug protein solution is placed from a lower chamber. Centrifugation (approximately 2000 x g) is applied to separate the bound and unbound fractions due to the high molecular size of compound-protein complex which cannot pass through the membrane. The free drug concentration in The simplest and fastest method for determining the concentration of the drug that is not binding to the plasma proteins during: - Drug discovery; - Clinical therapeutic drug monitoring; - Clinical pharmacodynamic and pharmacokinetic studies.