Drug Delivery and Disposition
The research expertise at the Laboratory for Pharmacotechnology and Biopharmacy lies in the area of the physicochemical and biopharmaceutical evaluation of drug candidates and dosage forms designed for extravascular administration. The main focus is to improve drug bioavailability both by a pharmacotechnological (new drug formulations) and a biopharmaceutical (based on knowledge of drug absorption mechanisms) approach. Pharmaceutical technology - Physical Pharmacy The Laboratory has gained considerable expertise in excipient evaluation and in different unit operations (mixing, granulation, coating, compaction) involved in the production of oral drug products. The physical chemistry of solid (molecular) dispersions prepared by hot melt extrusion or spray drying has been the focus of intensive research during the past years. It is the aim to correlate the physical structure of the dispersions to their pharmaceutical performance and stability profile. Analytical techniques such as thermal analysis (DSC, MTDSC, hot-s tage microscopy), X-ray powder diffraction, infrared spectroscopy and in vitro (intrinsic) dissolution testing are being used for this purpose. Recently, the Laboratory has expanded his research activities with the physicochemical analysis of self micro (nano) emulsifying drug delivery systems (sm(n)edds). The influence of formulation factors and lipolysis on the structure of the micro (nano) emulsions, and the influence of the structure of the emulsions on drug release is being investigated using thermal analysis, SAXS and in vitro dissolution testing. As part of the Center for Drug Delivery and Analysis, the Laboratory is also involved in formulation development and preformulation studies ordered by pharmaceutical companies. Biopharmacy The Laboratory has expertise and facilities to perform a wide range of investigations to assess drug absorption including the in vitro Cac o-2 cell culture system, the Ussing chamber system and the in situ intestinal perfusion system. These systems are being used to evaluate strategies to increase intestinal drug transport through modulation of the intestinal biochemical barrier function [metabolism (estera se, CYP3A), efflux carriers (P-gp, MRP)] in order to obtain improved drug delivery systems for oral administration. The analytical equipment also allows the quantitative determination of most drugs or drug candidates under investigation. The laboratory is able and licensed to perform whole animal absorption and pharmacokinetic experiments. In addition, a nasal cell culture system is being developed which allows (1) evaluating drug transport and (2) assessing the effect of drugs or excipients on the ciliary beat frequency (photometry system or high speed camera).