Interaction with Incorporated Drugs

In vivo the corresponding parameter to a K is A iiv, a parameter that is determined directly from in vivo experiments. Theoretically, K and K should be equal, but for the reasons outlined above they may not be. K is a direct measure of the molecular interaction of the drug with the enzyme. A iiv on the other hand is a measure of the actual in vivo effectiveness of the inhibitor. That is /(" iv, unlike Kj, automatically incorporates into its value the effects of factors such as differences in active site inhibitor concentration,... 

KARMA is an interactive computer assisted drug design tool that incorporates quantitative structure-activity relationships (QSAR), conformational analysis, and three-dimensional graphics. It represents a novel approach to receptor mapping analysis when the x-ray structure of the receptor site is not known, karma utilizes real time interactive three-dimensional color computer graphics combined with numerical computations and symbolic manipulation techniques from the field of artificial intelligence. 

It is not always appreciated that the application of in vivo gene therapy actually represents a drug delivery protocol. By the incorporation of plasmids into e.g. adenoviral or hposomal coats they are protected from degradation. Subsequent interaction with the target cells leads to intracellular delivery and then to nuclear localization of the plasmid. Although transfec-... 

Interaction with such properties does, however, not allow the investigator to answer the question of where the drug is localized in the particles (on the surface or in the crystal lattice). Thermal interactions were also observed when an incorporated drug or a second type of triglyceride formed a separate phase within the nanoparticles [3,37,64,68]. Drug release studies can provide supportive information on the accessibility of the drug to the aqueous phase [72,108], but separation of the effects from the nanoparticles from those of additional colloidal structures — if present — may be difficult. 

A quite different application of liposomes as reactive compartments is in the field of drug delivery. It was found several years ago that liposomes, because of their hydrophobic nature, strongly interact with the biological cell membrane and can actually be incorporated inside by endocytosis or other mechanisms, e.g., fusion (Allison and Gregoriadis, 1974 Gregoriadis, 1976a, b 1988 1995 Papa-hadjopoulus etah, 1989). 

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