Drugs drug immobilization

Vrakas, D., Giaginis, C., Tsantili-Kakoulidou, A. Different retention behavior of structurally diverse basic and neutral drugs in immobilized artificial membrane and reversed-phase high performance liquid chromatography ... 

Polyamines and their ammonium salts have been of interest because they are known to have potential applications as chelating agents (1-3), ion exchange resins (4-6), flocculants (7,8), and other industrial uses (9). Recent biomedical applications have constituted another important use of polymeric amines they have been investigated for use as biocompatable materials, polymeric drugs, immobilization of enzymes, cell-culture substratum and cancer chemotherapeutic agents (10-12). 

Some active materials are carriers for drugs (drug delivery systems), some have immobilized peptides to enable cell adhesion or migration, some are degradable by hydrolysis or by specific enzyme action. Some contain bioactive agents (e.g., heparin, thrombomodulin) to prevent coagulation or platelet activation while others incorporate bioactive groups to enhance osteo-conduction. Many include polyethylene oxide to retard protein adsorption and this is perhaps the closest we have come to a kind of inertness. 

R. B. Van Breemen, M. G. Bartlett, Y. Tsou, C. Culver, H. Swaisgood, S. E. Unger, Degradation of Peptide Drugs by Immobilized Digestive Proteases , Drug Metab. Dispos. 1991, 19, 683-690. 

The ACE analysis of interactions between drugs and phospholipid bilayers of liposomes present as a pseudostationary phase was performed by Zhang et al. (32). The capillaries were treated to eliminate electroendosmosis. Freshly prepared and essentially neutral small unilamellar liposomes composed of egg phosphatidylcholine were sucked into the capillary. These liposomes increased both the retention of four negatively charged drugs and the separation between the substances (Fig. 6). The chromatographic retentions of these drugs on immobilized phosphatidylcholine liposomes, ex-... 

Figure 6. Example of resolution of chiral drugs on immobilized /3-cyclodextrin derivatized with (S)-naph-thylethyl isocyanate leaving polar carbamoyl groups. Reprinted with permission from ref 62.

QSRR analysis of HPLC data determined on an immobilized human serum albumin (HSA) column helped to propose the topography of two binding sites of different affinity to benzodiazepine enantiomers 1143.163). Also, the mechanism of interaction of phenothiazine neuroleptics with melanin was rationalized by means of QSRR analysis of HPLC retention data [132,164]. Another QSRR study concerned the interactions of drugs with immobilized keratin and collagen [ 165). 

Khodorov BI. Sodium inactivation and drug-induced immobilization of the gating charge in nerve membrane. Prog Biophys Mol Biol 1981 37 49-89. 

Chan EC, Tan WL, Ho PC, Fang LJ. Modeling Caco-2 permeability of drugs using immobilized artificial membrane chromatography and physicochemical descriptors. J Chromatogr A 2005, 29 Apr 1072(2) 159-168. 

Rhabdomyolysis—The breakdown of muscle tissue and release of myoglobin and intracellular electrolytes into the circulation due to a variety of causes such as crush injuries, drug-induced immobilization, and status epilepticus. It often leads to acute renal failure. 

Magnetic polymer microsphere is a kind of microspheres which combines inorganic polymer and magnetic materials. It is magnetic and surface modifiable, therefore, has a wide application in the targeted drugs, immobilized enzyme and cell separation, etc. 

C. Lagercrantz, T. Laisson and H. Karisson, Binding of same fatty acids and drugs to immobilized bovine serum albumin studied by column affinity chromatography. Anal Biochem., 1979, 99, 352-364. 

The main applications of chitosan and the electrostatic complexes discussed are antithrom-bogenic materials, controlled-release encapsulation of drugs, immobilization of enzymes and cells, and gene carriers. The advantage of chitosan in such materials is its biodegradability but... 

Yoon CH, Kim SJ, Shin BS, Lee KC, and Yoo SD (2006) Rapid screening of blood-brain barrier penetration of drugs using immobilized artificial membrane phosphatidylcholine column chromatography J Biomol Screen 11 13-20. 

In a typical ASD, the drug (solute phase) is dispersed in an inert carrier (e.g., a polymeric continuous phase) with molecular level distribution being the most desirable. Depending on the interactions between drug and polymer and the method of preparation, the ASD may exist as a one-phase, two-phase, or mixed-phase system. In the one-phase system, the drug is immobilized within the polymer matrix at a molecular level such that it... 

Ab-drug (immobile/bound)<— Ab(immobile) H drug (free, unbound)... 

---