Degradation, pharmaceutical

Keywords Degradation, Pharmaceuticals, Toxicity, Transformation products, White-rot fungi... 

Brondsted, H. and Kopecek, J. (1992). Hydrogels for site-specific drug delivery to the colon— in vitro and in vivo degradation. Pharmaceut. Res., 9, 1540-1545. 

Reid DL, Calvitt CJ, Zell MT, Miller KG, Kingsmill CA. Early prediction of pharmaceutical oxidation pathways by computational chemistry and forced degradation. Pharmaceut Res 2004 21 1708-1717. 

Brondsted, H. and J. Kopecek, Hydrogels for. site-specific drug deliver) to the colon in vitro and in vivo degradation. Pharmaceutical Research, 9 (1992) 1.540-1545. 

Pharmaceutically useful steroids may be either obtained by total synthesis or by degradation and functional group conversions from inexpensive natural steroids. Both approaches will be discussed in this section (H. Langecker, 1977 R.T. Blickenstaff, 1974). 

Medical Uses. Citric acid and citrate salts are used to buffer a wide range of pharmaceuticals at their optimum pH for stabiUty and effectiveness (65—74). Effervescent formulations use citric acid and bicarbonate to provide rapid dissolution of active ingredients and improve palatabiUty. Citrates are used to chelate trace metal ions, preventing degradation of ingredients. Citrates are used to prevent the coagulation of both human and animal blood in plasma and blood fractionation. Calcium and ferric ammonium citrates are used in mineral supplements. 

Polycaprolactones (see also Section 25.11), although available since 1969, have only recently been marketed for biodegradable purposes. Applications include degradable film, tree planting containers and slow-release matrices for pharmaceuticals, pesticides, herbieides and fertilisers. Its rate of biodegradability is said to be less than that of the polylactides. 

A second strategy that is more likely to succeed is to interfere with the process of activation of NF-kB by blocking the activation of the IKK complex or the degradation of IkBs. Pharmaceutical companies are investing considerable effort in the development of... 

Organophosphate flame retardants and plasticisers Perfluorinated compounds Pharmaceuticals and personal care products Polar pesticides and their degradation/transformation products Surfactants and their metabolites... 

Quintana JB, Weiss S, Reemtsma T (2005) Pathways and metabolites of microbial degradation of selected acidic pharmaceutical and their occurrence in municipal wastewater treated by a membrane bioreactor. Water Res 39 2654-2664... 

Schultz MM, Furlong ET (2008) Trace analysis of antidepressant pharmaceuticals and then-select degradates in aquatic matrixes by LC/ESI/MS/MS. Anal Chem 80 1756-1762... 

Andry, M. C. Levy, M. C. (1997). In vitro degradation of serum albumin microcapsules Effect of process variables. International Journal of Pharmaceutics, Vol. 152, 2, (Jime 1997), pp. (145-151), ISSN 0378-5173... 

Complete phase-out of chlorinated compounds is being resisted not only by chlorine producers, but also by the many industries that use chlorine compounds in the manufacture of products from paper to pharmaceuticals. Meanwhile, chemists seek ways to degrade dioxins to nontoxic substances. 

Lindblom and Blander (1980) have given a number of examples of relevance in the pharmaceutical industry. These include C-alkylations, 0-alkylations, and A-alkylations. The C-alkylation of phenylacetonitrile, (mono- and di-) alkylation of benzylpenicillin with a-chlorodiethyl carbonate (where the acid part and the halide part in the esterification would have degraded quickly under normal conditions adopted for the reaction), A-alkylation of purines and adenine, etc. are discussed at some length and the supremacy of PTC is clearly shown. 

Before releasing a process column for chromatography, it is advisable to perform some test to measure efficiency, such as calculating height equivalent theoretical plates (HETP), both to forestall any problems in the column bed and to provide a benchmark by which to measure column reproducibility and predict degradation of the bed or material. Examples of compounds that are relatively innocuous for use in pharmaceutical applications are 1% NaCl (for gel filtration), concentrated buffer solutions (for ion exchange), and benzyl alcohol and parabens for reverse phase LC.10... 

---