Homogeneous and Informative

Froloff, N., Hamon, V., Dupuis, P., Otto-Bruc, A., Mao, B., Merrick, S. and Migeon, J. (2006) Construction of a homogeneous and informative in vitro profiling database for anticipating the clinical effects of drugs, in... 

Construction of a Homogeneous and Informative In vitro Profiling Database for Anticipating the Clinical Effects of Drugs... 

In this chapter we have described the construction of a high-quality, homogeneous and informative in vitro profiling database and its applications both to drug discovery and development. 

The results found for the coating controlled parts allow to consider during the testing the exploitation of the information provided by the measured variation impedance for the processed products by the coating thickness determination and low frequency homogeneity and to evaluate the high frequency coating nature. 

Various novel applications in biotechnology, biomedical engineering, information industry, and microelectronics involve the use of polymeric microspheres with controlled size and surface properties [1-31. Traditionally, the polymer microspheres larger than 100 /urn with a certain size distribution have been produced by the suspension polymerization process, where the monomer droplets are broken into micron-size in the existence of a stabilizer and are subsequently polymerized within a continuous medium by using an oil-soluble initiator. Suspension polymerization is usually preferred for the production of polymeric particles in the size range of 50-1000 /Ltm. But, there is a wide size distribution in the product due to the inherent size distribution of the mechanical homogenization and due to the coalescence problem. The size distribution is measured with the standard deviation or the coefficient of variation (CV) and the suspension polymerization provides polymeric microspheres with CVs varying from 15-30%. 

There are some aspects of process design in which decisions are based primarily on past experience rather than on quantitative performance models. Problems of this type include the selection of constraction materials, the selection of appropriate models for evaluating the physical properties of homogeneous and heterogeneous mixtures of components, and the selection of safety systems. Advances in expert systems technology and information management will have a profound impact on expressing the solutions to these problems. 

Other key features in the analysis of pore structure are the length scales associated with the various micro- (nano)-scale obstacles and pores, the possible larger-scale variations in structure, and the averaging domain over which information is needed [6,341,436], The hterature refers to analysis of homogeneous and heterogeneous porous media, where homogeneous refers to media with no variation in physical properties (e.g., porosity, diffu-... 

As mentioned before, RM producers go to great lengths, as are required by the ISO Guide 31 (1996) to prove homogeneity and stability, and to establish the best sample size and storage conditions for an optimal shelf life. This information is normally provided in the RM certificate. Nevertheless, users must pay particular attention to a number of procedures in the use of RMs to avoid invalid results. 

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