Physicochemical characterization, active

Comprehensive physicochemical characterization of any raw material is a crucial and multi-phased requirement for the selection and validation of that matter as a constituent of a product or part of the product development process (Morris et al., 1998). Such demand is especially important in the pharmaceutical industry because of the presence of several compounds assembled in a formulation, such as active substances and excipients, which highlights the importance of compatibility among them. Besides, variations in raw materials due to different sources, periods of extraction and various environmental factors may lead to failures in production and/or in the dosage form performance (Morris et al., 1998). Additionally, economic issues are also related to the need for investigating the physicochemical characteristics of raw materials since those features may determine the most adequate and low-cost material for specific procedures and dosage forms. 

Ramirez-Corredores, M. M. Mujica, E., and Salazar, J. A., Physicochemical characterization of VGO MHCK catalysts and its extrapolation to catalytic activity. Stud. Surf. Scien. Catal, 1999. 127 pp. 279-86. 

Halloysite was found to be a viable and inexpensive nanoscale container for the encapsulation of biologically active molecules and drugs as was first demonstrated by Price et al. [5-8]. Its physicochemical characterization as a novel drug delivery system was also reported by Levis and Deasy et al. [9,10], who further demonstrated the controlled release of diltiazem hydrochloride and propanol hydrochloride... 

Jurgens G, Muller M, Koch MH, et al. Interaction of hemoglobin with enterobacterial lipopolysaccharide and lipid A. Physicochemical characterization and biological activity. Eur J Biochem 2001 268 4233. 

It is now considered, by most groups working in this area, that vanadyl pyrophosphate (VO)2P207 is the central phase of the Vanadium Phosphate system for butane oxidation to maleic anhydride (7 ). However the local structure of the catalytic sites is still a subject of discussion since, up to now, it has not been possible to study the characteristics of the catalyst under reaction conditions. Correlations have been attempted between catalytic performances obtained at variable temperature (380-430 C) in steady state conditions and physicochemical characterization obtained at room temperature after the catalytic test, sometimes after some deactivation of the catalyst. As a consequence, this has led to some confusion as to the nature of the active phase and of the effective sites. (VO)2P207, V (IV) is mainly detected by X-Ray Diffraction. 

Zhang, Y., Yang, Y., Tang, K., Hu, X., Zou, G. (2008). Physicochemical characterization and antioxidant activity of quercetin-loaded chitosan nanoparticles. Journal of Applied Polymer Science, 107, 891-897. 

Tokunaga, T., Yamamoto, H., Shimada, S., Abe, H., Fukuda, T., Fujisawa, Y. et al. (1984) Antitumor activity of deoxyribonucleic acid traction from Mycobacterium bovis BCG. I. Isolation, physicochemical characterization, and antitumor activity. J. Natl. Cancer Inst., 72, 955-962. 

Godin, B., and E. Touitou. 2005. Erythromycin ethosomal systems Physicochemical characterization and enhanced antibacterial activity. Curr Drug Deliv 2 269. 

Fonseca, C., S. Simoes, et al. (2002). Paclitaxel-loaded PLGA nanoparticles preparation, physicochemical characterization and in vitro anti-tumoral activity. J Control Release 83(2) 273-286. 

Brandenburg, K., Wagner, F., Muller, M., Heine, H., Andra, J., Koch, M.H.J., Zahringer, U., Seydel, U. Physicochemical characterization and biological activity of a glycoglycerolipid from Mycoplasma fermentans. Eur J Biochem 270 (2003) 3271-3279. 

Seydel, U., Schromm, A.B., Brade, L., Gronow, S., Andra, J., Midler, M., Koch, M.H., Fukase, K., Kataoka, M., Hashimoto, M., Kusumoto, S., Brandenburg, K. Physicochemical characterization of carboxymethyl lipid A derivatives in relation to biological activity. FEBS J 272 (2005) 327-340. 

In this work, the effect of the activation temperature upon the kinetic behaviour of the catalyst has been studied The physicochemical characterization has been carried out by XPS and TPR, and the variation of the surface properties has been related to the observed hydrogenation and coke formation kinetics. 

The availability of sensitive analytical tests to adequately characterize a product and to measure the predicted possible changes is central to a comparability assessment. Obviously tests should be chosen that will be the most likely to detect important changes. ICH Q6B offers advice on physicochemical, biological activity, and immunochemical properties, purity (impurity), con-... 

The appropriate clinical program is influenced by many factors, including the degree of molecular complexity of the particular protein and the extent of physicochemical characterization the mode of action, indication(s), and use population(s) the presence of established structure-activity relationships and validated bioassays and the results of preclinical testing. 

The techniques listed in Table 3.4 are useful for the determination of purity and the presence of contaminating proteins. In addition to the physicochemical characterization and assays for bioactivity, the detection of undesirable biological activities arising from the protein product itself, and from contaminating proteins and other biomolecules is important, and is required by regulatory agencies. 

Arsonoliposomes (ARSL) which are liposomes that contain arsonolipids in their membranes have shown interesting anticancer and antiparasitic activity in vitro. Their lipid composition (the specific arsonolipids and/or phospholipids used for their preparation, and the relative amounts of each lipid type) highly influences their physicochemical properties as well as their in vivo kinetics and antiparasitic activity however, their cytotoxicity towards cancer cells is minimally - if at all - modified. ARSL are prepared by a modification of the one step method followed or not by sonication (for formation of sonicated or non-sonicated ARSL, respectively). Arsonoliposomes may be composed only of arsonolipids (containing or not cholesterol) [plain ARSL], or they may contain mixtures of arsonolipids with phospholipids (with or without Choi) [mixed ARSL]. Herein, we describe in detail the preparation and physicochemical characterization of ARSL. 

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