Drug delivery systems development

Modulation of GI Transit Time To modulate the GI transit time so that the drug delivery system developed can be transported to a target site or to the... 

Mechanism of Action Active Substance(s) Candidate Product Drug Delivery Systems Developers Clinical Trial Status... 

HaloLite, shown in Fig. 11, is a hand-held drug delivery system developed by Medic-Aid (Bognor Regis, United Kingdom). The device, which uses compressed air, consists of a medication chamber, a control unit, and an aerosol generation assembly that is operated by a portable, dedicated compressor. The aerosol is generated based upon conventional nebulization principles. The control unit allows the patient to select a... 

Presently, relatively little is known about the potency of drugs of abuse after inhalation or smoking. In order to deter-mine the relationship between volatility and pharmacological potency by the inhalation route, the authors developed an animal model to approximate the conditions of human inhalation. The approach involved a volatilization-inhalation drug delivery system developed over the past 10 years in this laboratory. The design of this inhalation apparatus is illustrated in figure 2. 

Figure 3. Microfluidic Device. (A) Time lapse illustrating repulsion the ejection of 1.9 pm fluorescent polystyrene microsphere particles from an electroactive microwell. After dissolution of the membrane, the fluorescent particles can be seen in the well. White hnes outline the gold electrodes features. Images are taken every 2 s (total of 10 s). (B) Schematic of the electroactive microwell drug delivery system developed here. Scale bar represents 2 mm. (C) Micro fluidic device with electrical leads connected to thin copper wires. Inset Magnified view of microchip from above looking at the region near the membrane. (D) To illustrate the electrokinetic transport processes involved in the ejection stage, a finite element analysis of time-dependent species transport of the system is shown. Images show cut view of species concentration every 60 s up to 300 s after the ejection process.

Since the development of the Spansule brand (Smith Kline Beech am) of coated beads and granules in the late 1960s, various dmg product technologies have been developed and patented to achieve extended durations of therapeutic effects. Each of these does so by various mechanisms of control of dmg release from adrninistered dosage forms. Each method has its advantages and disadvantages, a discussion of which is available in the pharmaceutical hterature (see Drug delivery systems) (21). 

TOF-SIMS has important potentials in many areas of life science, in fundamental and applied research as well as in product development and control. This holds for the characterization of biological cells and tissues, of sensor and microplate arrays, of drug delivery systems, of implants, etc. In all these areas, relevant surfaces feature a very complex composition and structure, requiring the parallel detect ion of many different molecular species as well as metal and other elements, with high sensitivity and spatial resolution requirements, which are exactly met by TOF-SIMS. 

As discussed earlier, noncollagenous proteins, particularly albumin and to a lesser extent gelatin, in the form of microspheres and nanoparticles continue to be exploited as drug delivery systems. Oppen-heim (71) and Speiser (72) reviewed the technology developed to produce ultrafine particles, often referred to as nanoparticles. 

The nanostructured molecular arrangements from DNA developed by Seeman may find applications as biological encapsulation and drug-delivery systems, as artificial multienzymes, or as scaffolds for the self-assembling nanoscale fabrication of technical elements. Moreover, DNA-protein conjugates may be anticipated as versatile building blocks in the fabrication of multifunctional supramolecular devices and also as highly functional-... 

Lipid bilayers affect drug delivery at several levels of pharmocokinetics, both at macroscopic and microscopic levels. Understanding the structure and function of the bilayers aids in the development of better drug delivery systems. Delivery is particularly important for the success of the gene-based drugs. 

Polymeric drugs and drug delivery systems / Richard L. Dunn, editor, Raphael M. Ottenbrite, editor, developed from a symposium sponsored by the Division of Polymeric Chemistry, Inc. at the 200th National Meeting of the American Chemical Society, Washington, D.C., August 26-31,1990. 

The success of any drug delivery system depends upon how it interacts with the biological system to deliver its drug at the optimum rate and at the site where it is needed. This paper discusses some of the considerations that must be made in developing successful drug delivery systems and the opportunities available if a comprehensive assessment is made of the pharmacology, pharmacokinetics, and pharmacodynamics involved. 

In this paper, then, the previously developed model (7) is extended to the calculation of erosion characteristics of a well described polymeric delivery system, the acid-catalyzed erosion of poly (ortho ester)s (2-6). This system is chosen as the example system because of the completeness of the data package in the open literature. It is expected that this modelling approach is also useful for other hydrolytically unstable polymeric drug delivery systems. 

A mathematical model has been developed which allows the calculation of the degradation of polymeric drug delivery systems. The model has been shown to accurately simulate both the drug release and molecular weight changes in such systems. The concentration of anhydride levels affect the erosion characteristics of... 

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