Pharmaceutical applications fundamentals

Mancoff (15) and Pentecost (16) have both described continuous filmcoating processes that have been primarily designed for pharmaceutical applications. The fundamental basis of such processes is as shown in the schematic outline described in Figure 18. 

Tong W-Y, Zhang T-Z, Fu X-Y (2006) Microbial biotechnology for pharmaceutics fundamental and application. Chemical Industry Press, Beijing... 

Dhaneshwar S. Supercritical fluid chromatography fundamentals and applications. Pharmaceut. Rev. 2007 5(1) online www.pharmainfo.net... 

There has been a surge of research activity in the physical chemistry of membranes, bilayers, and vesicles. In addition to the fundamental interest in cell membranes and phospholipid bilayers, there is tremendous motivation for the design of supported membrane biosensors for medical and pharmaceutical applications (see the recent review by Sackmann [64]). This subject, in particular its biochemical aspects, is too vast for full development here we will only briefly discuss some of the more physical aspects of these systems. The reader is referred to the general references and some additional reviews [65-69]. 

Rheology is the study of flow and deformation of materials under the influence of external forces. It involves the viscosity characteristics of powders, liquids, and semisolids. Rheological studies are also important in the industrial manufacture and applications of plastic materials, lubricating materials, coatings, inks, adhesives, and food products. Flow properties of pharmaceutical disperse systems can be of particular importance, especially for topical products. Such systems often exhibit rather complex rheological properties, and pharmaceutical scientists have conducted fundamental investigations in this area [58-64],... 

Membrane diffusion illustrates the uses of Fick s first and second laws. We discussed steady diffusion across a film, a membrane with and without aqueous diffusion layers, and the skin. We also discussed the unsteady diffusion across a membrane with and without reaction. The solutions to these diffusion problems should be useful in practical situations encountered in pharmaceutical sciences, such as the development of membrane-based controlled-release dosage forms, selection of packaging materials, and experimental evaluation of absorption potential of new compounds. Diffusion in a cylinder and dissolution of a sphere show the solutions of the differential equations describing diffusion in cylindrical and spherical systems. Convection was discussed in the section on intrinsic dissolution. Thus, this chapter covered fundamental mass transfer equations and their applications in practical situations. 

At the moment, most of these more exotic bacteria are mainly used in expression for fundamental studies. Considering the speed of developments in biotechnology, their application for industrial or pharmaceutical protein production might become even more important very soon. 

To summarize, it should be highlighted that in general terms the issue of prescribing incentives is approached with a marked lack of consideration of such fundamental concerns as their impact on health, although this aspect is indirectly addressed by non-financial incentives and mixed formulas such as those discussed above. Financial incentives alone appear to lack effectiveness as instruments of pharmaceutical policy. Incentives aimed at prescribers should under no circumstances create a clash of interests between their fees and the quality of the care they provide for their patients, and therefore adjustment must be made in these terms. In turn, we cannot ignore that the effect of this type of mechanism on physicians behaviour will depend on, among other factors, the quality of available information on the aspects taken into consideration in their application. 

The preclinical knowledge base is initially developed by designing studies to answer fundamental questions. The development of this knowledge base is generally applicable to most pharmaceuticals as well as biopharmaceuticals, and include data to support (1) the relationship of the dose to the biological activity, (2) the relationship of the dose to the toxicity, (3) the effect of route and/or schedule on activity or toxicity and (4) identification of the potential risks for subsequent clinical studies. These questions are considered in the context of indication and/or disease state. In addition there are often unique concerns related to the specific category or product class. 

Solubility modelling with activity coefficient methods is an under-utilized tool in the pharmaceutical sector. Within the last few years there have been several new developments that have increased the capabilities of these techniques. The NRTL-SAC model is a flexible new addition to the predictive armory and new software that facilitates local fitting of UNIFAC groups for Pharmaceutical molecules offers an interesting alternative. Quantum chemistry approaches like COSMO-RS [25] and COSMO-SAC [26] may allow realistic ab-initio calculations to be performed, although computational requirements are still restrictive in many corporate environments. Solubility modelling has an important role to play in the efficient development and fundamental understanding of pharmaceutical crystallization processes. The application of these methods to industrially relevant problems, and the development of new... 

Since its creation around 1973, modern high-pressure liquid chromatography (HPLC) has played a dominant role in the analysis of pharmaceuticals. It is used in many different applications for example, in content uniformity assays and stability-indicating methods, for the purity profiles of drug substances, or in the analysis of drug metabolism in animals and humans. The heart of all of these assays is the HPLC column. In this chapter, we will describe the fundamental properties of HPLC columns as well as how these properties influence column performance and separation characteristics in pharmaceutical assays. 

The second part deals with applications of solvent extraction in industry, and begins with a general chapter (Chapter 7) that involves both equipment, flowsheet development, economic factors, and environmental aspects. Chapter 8 is concerned with fundamental engineering concepts for multistage extraction. Chapter 9 describes contactor design. It is followed by the industrial extraction of organic and biochemical compounds for purification and pharmaceutical uses (Chapter 10), recovery of metals for industrial production (Chapter 11), applications in the nuclear fuel cycle (Chapter 12), and recycling or waste treatment (Chapter 14). Analytical applications are briefly summarized in Chapter 13. The last chapters, Chapters 15 and 16, describe some newer developments in which the principle of solvent extraction has or may come into use, and theoretical developments. 

The first demonstration of solid state fluorescence of API dates back to 1961, while its in-line use for final drug product manufacturing was not demonstrated until recently." While in its infancy as a process analytical technology for real-time monitoring and product parametric real-time release, the applications identified and in some instances demonstrated include (i) blend endpoint API content nniformity detection " (ii) segregation monitoring or API content at various process critical control points and (iii) at-line tablet content uniformity determination. The fundamentals of solid-state luminescence spectroscopy for pharmaceutical solids has been covered by Brittain."... 

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