Polyhydroxyalkanoates: the natural biopolyester for future medical innovations

Polyhydroxyalkanoates (PHAs) are a family of natural microbial biopolyesters with the same basic chemical structure and diverse side chain groups. Based on their excellent biodegradability, biocompatibility, thermoplastic properties and diversity, PHAs are highly promising medical biomaterials and elements of medical devices for applications in tissue engineering and drug delivery. However, due to the high cost of biotechnological production, most PHAs have yet to be applied in the clinic and have only been studied at laboratory scale. This review focuses on the biosynthesis, diversity, physical properties, biodegradability and biosafety of PHAs. We also discuss optimization strategies for improved microbial production of commercial PHAs via novel synthetic biology tools. Moreover, we also systematically summarize various medical devices based on PHAs and related design approaches for medical applications, including tissue repair and drug delivery. The main degradation product of PHAs, 3-hydroxybutyrate (3HB), is recognized as a new functional molecule for cancer therapy and immune regulation. Although PHAs still account for only a small percentage of medical polymers, up-and-coming novel medical PHA devices will enter the clinical translation stage in the next few years.

Automated summary

Polyhydroxyalkanoates (PHAs) are natural microbial biopolyesters with excellent properties for medical applications, such as biodegradability and biocompatibility. This review focuses on the biosynthesis, physical properties, and optimization strategies of PHAs. The use of PHAs in medical devices for tissue engineering and drug delivery is also discussed, along with their potential as functional molecules in cancer therapy and immune regulation. Although currently only a small percentage of medical polymers, novel medical PHA devices are expected to enter the clinical translation stage in the near future.