Polymeric prodrugs

Abstract

In 1975 Prof. H. Ringsdorf proposed a model for rational design of polymeric prodrugs [J. Polym. Sci. Symp. 51 (1975) 135]. The model has been the most important basis for research in the field, since it was the first model that took into account both the chemical and biological aspects needed for the design of polymeric prodrugs. This paper deals with the most important properties that were discovered by designing polymeric prodrugs: prolongation of action of the drug, controlled release of the drug, passive tumor accumulation by the EPR-effect and alteration of body distribution and cell uptake. Over the years, other objectives have been formulated and other properties of polymer-drug conjugates were discovered. One recent example, the immunoprotective ability of polymeric prodrugs, is described in more detail in this paper.

Enzyme-Responsive Intracellular Controlled Release Using Nanometric Silica Mesoporous Supports Capped with “Saccharides”

“…Traditional delivery systems are in most cases based on polymers that usually release their cargo via diffusion-controlled processes or through degradation of the polymer container. [1][2][3][4][5][6][7] In recent years, as an alternative to polymeric materials, silica mesoporous supports (SMPS) have been used as inorganic scaffolds for the storage and release of drugs and organic molecules. [8][9][10] Silica mesoporous supports provide unique features such as stability, biocompatibility, large load capacity, and the possibility to include gate-like scaffoldings on the external surface for the design of nanodevices for on-command delivery applications.…”

Recent advances in materials for extended-release antibiotic delivery system

“…Various small molecular bioactive agents have been bound via degradable covalent linkages to many different polymeric systems to control the release of the agents. 64 For example, cellulose xanthatemetal-tetracycline complex was prepared to arrest the release of agents. Compared with a mixture of cellulose, metal and tetracycline, the tetracycline release from the cellulose-metal-tetracycline complexes was greatly sustained, which have been manifested by the antibacterial activity lasted for 7-22 days.…”

Polymer-Drug Nanoconjugate – An Innovative Nanomedicine: Challenges and Recent Advancements in Rational Formulation Design for Effective Delivery of Poorly Soluble Drugs

“…Therefore research efforts have been focused on stabilizing nanosized amorphous API particularly for poorly soluble drugs because the amorphous form is known to exhibit higher saturation solubility and dissolution velocity due to its ability to generate supersaturated drug solution during dissolution compared with the crystalline form (15,16). The higher dissolution rates have also been linked to higher bioavailability in vivo provided that supersaturation is sustained for sufficient period of time for absorption to occur (17)(18)(19). Stable amorphous polymer-drug nanoconjugate formulations are highly promising because they combine nanoscale formulation with enhanced solubility and bioavailability which may provide a platform for reduced dosing, toxicity and undesirable side effects of the API as well as controlled release and site specific nano-targeted drug delivery.…”