Drug targeting systems

For practical purposes, measures of the effectiveness of drug targeting are required. Such measures have been derived based on the pharmacokinetic profiles of the drug targeting system and that of the active drug. 

Nowadays, there can be no doubt that the application of pharmacokinetic and pharmacodynamic principles in the design of effective drug targeting systems is essential [1,2]. This may be illustrated by the following examples. 

In principle, a stabilized liposome might be valuable as a passive drug targeting system since the site of disposition in the body is significantly influenced by the diameter of the vesicle. For example, small liposomes below -50 nm diameter can pass through the capillary wall surrounding a tumor, allowing suitably surface-modified... 

For example, the use of a conically shaped lipid, dioleoylphos-phatidylethanolamine (DOPE), in cationic liposomes helps the destabilization of the cellular membranes, leading to a more efficient delivery of plasmid DNA in cell culture.84 The structural diversity of the lipidic colloids offers great flexibility in their applications as drug delivery and drug targeting systems. 

Drug loading and retention. As discussed previously, a successful drug targeting system needs to retain the encapsulated drug until it reaches... 

Crommelin, D. J. A., Hennink, W. E., and Storm, G. Drug targeting systems Fundamentals and applications to parental drug delivery, in Hilleiy, A. M., Lloyd, A. W., and Swarbrick, J., (eds.), Drug Delivery and Targeting for Pharmacists and Pharmaceutical Scientists. London Taylor and Francis, 2001. 

D. K. F. Meijer, R. W. Jansen, and G. Molema, Drug targeting systems for antiviral agents options and limitations, Antiviral Res. 18 215 (1992). 

Chapter 5 Drug Targeting Systems Fundamentals and Applications to Parenteral Drug 105... 

Zhang Y, Pardridge WM (2001b) Neuroprotection in transient focal brain ischemia after delayed intravenous administration of brain-derived neurotrophic factor conjugated to a blood-brain barrier drug targeting system. Stroke 32 1378-1384. 

Trubetskoy, V.S. Berdichevsky, V.R. Efremov, E.E. Torchilin, V.P. On the possibility of the unification of drug targeting systems studies with liposome transport to the mixtures of target antigens. Biochem. Pharmacol. 1987, 36, 839-842. 

Biological ghosts have been identified as potential drug targeting systems. However, additional studies are needed to investigate the in vivo advantages and potential safety issues of such (Table 2). 

Daan JA, Hennink WE, Storm G (2002) Drug targeting system fundamentals and applications to parenteral drug delivery In HiUery AM, Lloyd AW, Swarbrick J (eds) Drug delivery and targeting for pharmacists and pharmaceutical scientists. Routledge, UK... 

Daan JA, Hennink WE, Storm G (2002) Drug targeting system fundamentals and... 

The effective clinical use of radiosensitizers requires the development of drug targeting systems and the investigation of imaging techniques to noninvasively monitor the biodistribution of the agent. A F-labeling technique in combina-... 

The following is an example of a novel drug-targeting system for cellular internalization using TAT. The delivery system consists of two components (1) a polymeric micelle that has a hydrophobic core of poly(L-lactic add) (PLLA) and a hydrophilic shell of PEG conjugated to TAT (TAT micelle) (2) an ultra-pH-sensitive diblock copolymer of poly(methacryloyl sulfadimethoxine) (PSD) and PEG (PSD/PEG) [199]. The final carrier system is formulated by complexation of the anionic PSD with the cationic TAT of the micelles. The complex formulation and TAT peptide can be systemically shielded. However, TAT is exposed to slightly acidic tumor pH levels due to disassembly of the complexed micelle. 

S])ccific Drug Targeting System based on PHA NanopaiTielcs PhaP and Ligands fused to PhaP... 

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