Fabrication of 3D objects incorporating peptides covalently attached via reversible disulfide linkages with potential for controlled drug release†

Bioapplication of 3D printing in the fabrication of scaffolding, implants of organ replacements/recovery, etc. has been drawing increasing interest due to its capability to replicate complex structures present in organs, etc. Alongside the structure and physical properties, the functionality of printed parts is equally important to deliver appropriate materials for this type of application. Herein, complex structures integrated with a reversibly covalently linked peptide have been fabricated with high resolution via digital light processing (DLP) type VAT photopolymerization. Bisacryloyl cystamine was synthesized and incorporated into the printer resin to include disulfide functionality in some of the crosslinks. The printed objects were subsequently treated with tris(2-carboxyethyl) phosphine (TCEP) and loaded with covalently bound lanreotide, as an example of a disulfide bearing peptide, via a thiol–disulfide exchange. The uptake of lanreotide and subsequent release by a second reductive treatment of TCEP were monitored. This current method was successful in producing objects different structures capable of reversiblly binding functional peptides with the potential for a controlled release profile by adjusting the crosslink density and disulfide content in the objects has been investigated.