THE ROLE OF SCANNING PROBE MICROSCOPY IN DRUG-DELIVERY RESEARCH

The success of a drug delivery system is often dependent on the surfac e properties of the device. These surface properties will determine th e complex dynamic interfacial events that occur when the system is int roduced into the aqueous environment of a patient. Development of the scanning probe microscopes has provided a number of very powerful new surface analytical techniques that are making a significant contributi on to the characterization of drug delivery systems and the interfacia l processes that occur when such systems are exposed to aqueous living environments. In this review, we describe the design and attributes o f these instruments and discuss the impact of the techniques on a wide range of drug delivery research. The scanning probe microscopes are p roviding new insights into important problems concerning drug delivery , including the molecular structure of polymeric biomaterial surfaces, the conformation of target biomolecules, the influence of morphology on biodegradation, the adsorption of proteins to synthetic surfaces, a nd the structure and interactions of colloidal particles. As the whole field of scanning probe microscopy continues to advance, drug deliver y research is set to benefit; in the final section of the review, the future potential derived from the ability to characterize new surface properties under aqueous conditions is discussed.