Biodegradable Polymeric Carriers

Mero A, Schiavon O, Pasut G, Veronese EM, Emilitri E, Fermti P (2009) A biodegradable polymeric carrier based on PEG for dmg delivery. J Bioact Compat Polym 24 220-234... 

Proteins have also been used as delivery agents. Thus, Meyers and Bichon used a noninmnmoglobulin that preferentially binds to a tumor cell receptor in conjimction with a bonded biodegradable polymeric carrier that contains cytotoxic molecules. 

Macromolecules as drug carriers may be divided into degradable and nondegradable types based on their fate within the organism. Biodegradable polymeric drug carriers are traditionally derived from natural products polysaccharides, poly(amino acids) in the hope that the body s natural catabolic mechanisms will act to break down the macromolecular structure into small,... 

Polymeric carriers are biodegradable or water-soluble polymer matrices, typically in the form of colloidal-sized particles (microspheres or nanospheres), rods, or films. The active agent is entrapped within but not chemically bonded to the matrix. The drug is released in a sustained fashion as the polymer is dissolved or degraded, eroded, and finally resorbed [24,30,58-62]. 

Biodegradable polymeric materials have been used successfully in protein delivery. Some of the characteristics of biodegradable carriers that can be manipulated to maintain protein stability include water swelling, hydrophobicity, and chemical nature of degradation products [79],... 

Over the last decades, several academic and industrial research programs have been focused on the development and production of appropriate biocompatible formulations that provide enhanced therapeutic performance. Three different strategies can be discerned that are applied separately or in combination (i) addition of excipients to proteins, such as protease inhibitors, penetration or absorption enhancers like bile salts, fatty acids, cyclodextrins or surfactants " (ii) modification of the physicochemical properties of proteins, e.g. by attachment of lipophilic or hydrophilic moieties or (iii) incorporation of proteins into polymeric or liposomal delivery carriers. " A variety of polymeric vectors has been developed and exploited for this purpose, including biodegradable nanoparticles, nanogels, micelles, polymer bioconjugates and soluble nanocomposites. These polymeric carriers are more extensively described in the following sub-sections. 

Duncan and Izzo" listed in their seminal review on dendrimer toxicity some general consideration for polymers and dendrimers for in vivo applications "As a general rule, for any polymeric carrier to be suitable for parenteral application it is essential that the carrier is non-toxic and non-immunogenic, and it should preferably be biodegradable. It must display an inherent body distribution that will allow appropriate tissue targeting to the desired site, but... 

---