Pseudomonassp. as a Source of Medium Chain Length Polyhydroxyalkanoates for Controlled Drug Delivery: Perspective

Abstract

<jats:p>Controlled drug delivery technology represents one of the most rapidly advancing areas of science. They offer numerous advantages compared to conventional dosage forms including improved efficacy, reduced toxicity, improved patient compliance and convenience. Over the past several decades, many delivery tools or methods were developed such as viral vector, liposome-based delivery system, polymer-based delivery system, and intelligent delivery system. Recently, nonviral vectors, especially those based on biodegradable polymers, have been widely investigated as vectors. Unlike the other polymers tested, polyhydroxyalkanoates (PHAs) have been intensively investigated as a family of biodegradable and biocompatible materials for<jats:italic>in vivo</jats:italic>applications as implantable tissue engineering material as well as release vectors for various drugs. On the other hand, the direct use of these polyesters has been hampered by their hydrophobic character and some physical shortcomings, while its random copolymers fulfilled the expectation of biomedical researchers by exhibiting significant mechanical and thermal properties. This paper reviews the strategies adapted to make functional polymer to be utilized as delivery system.</jats:p>

Poly(hydroxy alkanoate)s in Medical Applications

“…The area most considered for possible application of PHAs and PHA blends is the area of medical applications1,8,58,76–84. The usage as a system for drug delivery is perhaps the longest investigated application in this area, but still a highly active field85,86. Naveen et al synthesized nanofibers mats of PHB by electrospinning and loaded them with Kanamycin sulphate to test against Staphylococcus aureus .…”

Development of an injectable PHBV microparticles-GG hydrogel hybrid system for regenerative medicine

“…Among the biodegradable polymers that have been explored for the production of DDS, poly(lactide-co-glycolide) (Wen et al, 2013), poly(L-lactic acid) (Correia et al, 2013), chitosan (Champa and Bhat, 2010), alginate (Iwanaga et al, 2013), starch-poly-e-caprolactone (Balmayor et al, 2009) and polyhydroxyalkanoates (PHAs) are the most used. From the PHA family, polyhydroxybutyrate (PHB) and its co-polymer with hydroxyvalerate (PHBV) in particular, in addition to TE applications (Zonari et al, 2014), have been also proposed as delivery systems for various active agents (Shishatskaya et al, 2008;Chen and Tong, 2012;Kabilan et al, 2012). PHAs microparticles (MPs) have been developed by different microencapsulation approaches that rely on solvent-evaporation methods, emulsification-diffusion, among others.…”

Engineered biosynthesis of biodegradable polymers

“…It is accumulated in bacteria at up to 80 % of the dry cell weight and it has material properties very similar to conventional plastics like polyethylene and polypropylene. But, PHB is a brittle and rigid polymer with low flexibility and has high melting temperature (170 °C) making polymer processing difficult [65,70]. On the other hand, medium-chain-length PHAs are made up of longer monomers and are typically elastomers having high flexibility.…”