Drug release system

The development of new polyanhydrides has sparked researchers to developed new device fabrication and characterization techniques, instrumentation, and experimental and mathematical models that can be extended to the study of other systems. The growing interest in developing new chemistries and drug release systems based on polyanhydrides promises a rich harvest of new applications and drug release technologies, as well as new characterization techniques that can be extended to other materials. Future endeavors will likely focus on multicomponent polyanhydride systems, combining new chemical functionalities to tailor polyanhydrides for specific applications. 

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... 

M. Tanihara, Y. Suzuki, Y. Nishimura, K. Suzuki, Y. Kakimaru, Thrombin-Sensitive Peptide Linkers for Biological Signal-Responsive Drug Release Systems , Peptides 1998, 19, 421 -425 M. Tanihara, Y. Suzuki, Y. Nishimura, K. Suzuki, Y. Kakimaru, Y. Fukunishi, A Novel Microbial Infection-Responsive Drug Release System , J. Pharm. Sci. 1999, 88, 510-514. 

Oral controlled drug-release systems are increasingly used for short half-life drugs to reduce peak blood levels and side-eflfects, to maintain optimum drug concentration and to stimulate patient compliance. In order to maintain a constant blood-level of the drug during an extended period, a constant in vitro drug release rate is desired. The most popular controlled-release system is the matrix tablet (Desai et al., 1965). Te Wierik et al. (1996) reported on... 

The finding that intragranular polymer networks can undergo phase transition, and that product release in secretion might operate in a way similar to the newly developed drug release systems based on intelligent polymers, opens a... 

The use of siloxane polymers in applications such as separation membranes, drug release systems, and blood oxygenators requires extensive permeability studies. This, of course, also involves measurements of diffusivity and solubility.16... 

Hirayama, F., and Uekama, K. Cyclodextrin-based controlled drug release system. Adv. Drug Deliv. Rev. 36(1) 125-141, 1999. 

Ueda, S., Hata, T., Asakura, S., et al. Development of a novel drug release system, time-controlled explosion system (TES) I. Concept and design. J. Drug Target. 2 35-44, 1994. 

Optimum controlled drug release systems, for example, for medical applications, cosmetics or agriculture ... 

Tanihara M, Suzuki Y, Nishimura Y et al. (1998) Thrombin-sensitive peptide linkers for biological signal-responsive drug release systems. Peptides 19 421-425... 

Bernkop-Schnurch, A., Scholler, S. and Biebel, R.G. (2000) Development of controlled drug release systems based on thiolated polymers. J. Control. Release 66 39-48. 

Fig. 12. Model scheme for an on-off switching drug release system consisting of a biochipsensor and a drug including an electrically responsive hydrogel...

The term / kl2 in the above equations is called the Deborah number, Dc for the drug release system ... 

Molecular electronics Electrical displays Chemical biochemical and thermal sensors Rechargeable batteries and solid electrolytes Drug release systems Optical computers Ion exchange membranes Electromechanical actuators Smart structures Switches... 

Watanabe, S., Kawai, H., Katsuma, M., and Fukul, M. (2002), Colon-specific drug release system, U.S. Patent 6,368,629. 

Two major types of advanced drug release systems have been designed on the basis of insertion of a solid device in the eye.The first is a device of low permeability filled with drug (Ocusert), which has been discontinued. The second is a polymer that is completely soluble in lacrimal fluid, formulated with drug in its matrix (Lacrisert). Both systems can be made to approach zero-order kinetics. However, patient acceptance has been poor. 

Bruck, S.D. Mueller, E.P. Materials and biological aspects of synthetic polymers in controlled drug release systems problems and challenges. Critical Reviews in Therapeutic Drug Carrier Systems 1988, 5 (3), 171-187. 

Ratner, B.D. Reducing capsular thickness and enhancing angiogenesis around implant drug release systems. J. Controlled Release 2002, 78 (1-3), 211-218. 

Polyanhydrides are promising as biomaterials because they possess a unique combination of properties that include hydrolytically labile backbone, hydrophobic bulk, and chemistry that can be easily combined with other functional groups to design novel materials. These materials are primarily surface-erodible and offer the potential to stabilize protein drugs and sustain release from days to months. The microstructure characteristics of copolymer systems can be exploited to tailor drug release profiles. The versatility of polyanhydride chemistry promises a new class of drug release systems for specific applications. 

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