Nonwoven and Hydrogel Poly(glycerol sebacate) (PGS)-Based Materials for Repair of Foot Plantar Defects

Diabetic ulcers are a common and painful complication arising from diabetes, ultimately undermining the structure and functional competency of the foot. One of the consequences is the loss of soft fatty tissues on the base of the foot, referred to as the ‘fat pad’. This compromises the load bearing capability of the foot leading to further dysfunction as well as pain for the patient. Current treatments involve implantation of a replacement elastomeric material to account for the lost fatty tissue. These methods are costly, have poor success rates and the results are often sub-optimal due to short implantation times, the migration of implant material and incompatibility of mechanical properties with the surrounding tissue. From a clinical perspective, the development of a new elastomeric support material suitable for implantation is highly desirable.
In this research, a new PGS-based elastomeric polymer, poly(glycerol-co-sebacic acid-co-lactic acid-co-polyethylene glycol) (PGSLP8000) was developed with photo-curing capabilities. The polymer synthesis, modification and processing into hydrogels and fibres, as well as the characterisation of resulting materials are reported. PGSLP8000 nanofibre nonwoven webs were produced for the first time by electrospinning after commixing with Poly(caprolactone). Novel PGSLP Acrylate nanofibre-hydrogel matrices (composite structures) were also manufactured, and it was found that incorporation of the fibres allowed modulation of bulk compression properties.