Forming process overview

Carpena, J., Audubert, F Bernache, D., Boyer, L., Donazzon, B., Lacout, J. L. Senamaud, N. 1998. Apatitic waste forms Process overview. Materials Research Society Symposium Proceedings, 506, 543-549. 

This overview has focused on those impurities brought into the drug product system by excipients or dosage form processing likely to cause stability or performance issues in the dosage form. The sources of the impurities are discussed as well as how they affect dosage forms or represent product issues. In particular, those impurities that lead to drug stability issues are reviewed. 

Pfaender, H.G. (1983) Schott Guide to Glass, Van Nostrand Reinhold, New York. A concise overview of glass-forming processes. 

This section provides an overview of the synthesis of dyes and pigments used in textiles and related industries. Dyes are soluble at some stage of the application process, whereas pigments, in general, retain essentially their particulate or crystalline form during application. A dye is used to impart color to materials of... 

The following section describes as an example the sulfonation of toluene to />-toluenesulfonic acid. Concerning the formation of byproducts, see page 81. Figure 24 gives an overview of the process [162]. The maunufacture of p-toluenesulfonic acid follows continuously by the conversion of alkylbenzene with 96-100% sulfuric acid in the mixing vessel Rl. The formed water is re-... 

Amphipilic polypeptides that are synthesized with appropriate ratios of hydrophilic to hydrophobic blocks can form ordered vesicular shapes. Although many polypeptides can self-assemble into vesicles when simply dissolved in the correct solvent, others require more processing steps. This section provides an overview of the techniques that have been developed to process various polypeptide and polypeptide hybrid systems into vesicles. 

Organometallic polymer precursors offer the potential to manufacture shaped forms of advanced ceramic materials using low temperature processing. Polysilazanes, compounds containing Si-N bonds in the polymer backbone, can be used as precursors to silicon nitride containing ceramic materials. This chapter provides an overview of the general synthetic approaches to polysilazanes with particular emphasis on the synthesis of preceramic polysilazanes. 

An overview about more than 10 years of R D activities on solid electrolyte interphase (SEI) film forming electrolyte additives and solvents at Graz University of Technology is presented. The different requirements on the electrolyte and on the SEI formation process in the presence of various anode materials (metallic lithium, graphitic carbons, and lithium storage metals/alloys are particularly highlighted. 

Various other biphasic solutions to the separation problem are considered in other chapters of this book, but an especially attractive alternative was introduced by Horvath and co-workers in 1994.[1] He coined the term catalysis in the fluorous biphase and the process uses the temperature dependent miscibility of fluorinated solvents (organic solvents in which most or all of the hydrogen atoms have been replaced by fluorine atoms) with normal organic solvents, to provide a possible answer to the biphasic hydroformylation of long-chain alkenes. At temperatures close to the operating temperature of many catalytic reactions (60-120°C), the fluorous and organic solvents mix, but at temperatures near ambient they phase separate cleanly. Since that time, many other reactions have been demonstrated under fluorous biphasic conditions and these form the basis of this chapter. The subject has been comprehensively reviewed, [2-6] so this chapter gives an overview and finishes with some process considerations. 

The physicochemical and other properties of any newly identified drug must be extensively characterized prior to its entry into clinical trials. As the vast bulk of biopharmaceuticals are proteins, a summary overview of the approach taken to initial characterization of these biomolecules is presented. A prerequisite to such characterization is initial purification of the protein. Purification to homogeneity usually requires a combination of three or more high-resolution chromatographic steps (Chapter 6). The purification protocol is designed carefully, as it usually forms the basis of subsequent pilot- and process-scale purification systems. The purified product is then subjected to a battery of tests that aim to characterize it fully. Moreover, once these characteristics have been defined, they form the basis of many of the QC identity tests routinely performed on the product during its subsequent commercial manufacture. As these identity tests are discussed in detail in Chapter 7, only an abbreviated overview is presented here, in the form of Figure 4.5. 

Figure 8.7 Overview of the manufacture of Betaferon, a recombinant human IFN-(3 produced in E. coli. The product differs from native human IFN-(3 in that it is unglycosylated and cysteine residue 17 had been replaced by a serine residue. E. coli fermentation is achieved using minimal salts/glucose media and product accumulates intracellularly in inclusion body (IB) form. During downstream processing, the lbs are solubilized in butanol, with subseguent removal of this denaturant to facilitate product refolding. After two consecutive gel-filtration steps, excipients are added, the product is filled into glass vials and freeze-dried. It exhibits a shelf life of 18 months when stored at 2-8 °C...

Figure 10.1 A simplified overview of the haematopoietic process as currently understood. Refer to text for details (BFU burst forming unit)...

In this sub-Section a concise overview will be presented of safety indicators commonly used in current chemical process industry. Safety Indicators in this Chapter are restricted to the safety related risk indicators present in an organization. The Sis defined here are present in the chemical process industry in the form of operational data, and in the form of results from (safety) tools. In both cases the Sis aim to indicate the safety status, or risks, Marono (Marono et al., 1998). To retrieve the risk coverage area of commonly used Sis, both the tools, as well as the data they are based on have to be known. The relations between data, tools, and indicators are depicted graphically in Figure 10. 

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