Controlled-release delivery systems formulation

Dong, L., V fong, P, and Espinal S., L-OF S)BARDCAP a new osmotic delivery system for controlled release of liquid formulation, poster presentat28tfi International Symposium of Controlled Release of Bioactive Materials, San Diego, June, 2001. 

For drugs that possess low water solubility a number of formulation strategies have been examined to enhance their solubility and hence the rate of release from osmotically controlled drug delivery systems. Examples of these approaches include ... 

DOX and QDs were co-encapsulated into the hydrophobic core of the micelles, the release kinetics was carried out in order to confirm the sustained release of the DOX and the therapeutic efficacy of the obtained micellar formulation was tested in vitro using HeLa cell line. In the aim to evaluate the cellular uptake behavior of the micelles, in vitro imaging studies were also performed. The results indicated the sustained release of the drug and the potential of these micellar systems as efficient optical fluorescence imaging and controlled drug delivery systems. 

The concept of fibrous polymer formulations was extended to the delivery of aquatic herbicides (56). Several herbicides including Diquat, Fluridone, and Endothal were spun into biodegradable poly-caprolactone. Monolithic fibers and a modified monolithic system were produced with levels of herbicide from 5 to 60% by weight. Laboratory and field trials showed efficacious delivery of the active agent. Fibers provided both targeted localized delivery and controlled release of the herbicide to the aquatic weed. 

As pharmaceutical scientists gain experience and tackle the primary challenges of developing stable parenteral formulations of proteins, the horizons continue to expand and novel delivery systems and alternative routes of administration are being sought. The interest in protein drug delivery is reflected by the wealth of literature that covers this topic [150-154]. Typically, protein therapeutics are prepared as sterile products for parenteral administration, but in the past several years, there has been increased interest in pulmonary, oral, transdermal, and controlled-release injectable formulations and many advances have been made. Some of the more promising recent developments are summarized in this section. 

There is some confusion concerning terminology used for drug delivery when control of drug release is discussed. Within this chapter we will use an empirical approach. When a drug-delivery system does not contain any design element (formulation or process attribute) that is included to modify either spatial or... 

In the above trial [70] rifaximin was dissolved in chloroform and applied by repeated painting. After the solvent had dried a red sludge persisted over the dental structures allowing a continuous antimicrobial effect. Better delivery systems, such as subgingival controlled release preparations [12], are, however, needed to fully exploit the rifaximin potential in periodontal disease. In this connection, a gum-like device [71] has been developed that allows a controlled and continuous release of the antibiotic within the oral cavity. Large double-blind controlled trials using this and other formulations are now needed to establish the best therapeutic regimen for this indication. 

Controlled drug delivery, membrane technology in, 15 847-848 Controlled drug release formulations (CDRFs), 9 51, 55 polymers in, 9 71-73 Controlled drug release systems, 9 50-51 design, 9 51-52 development, 9 55-57 intelligent, 9 56-57 in market, 9 83—85... 

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