Chitosan-Vitamin C Complex: A Nature-Inspired Adhesive for Bonding Poly(methyl methacrylate) Devices for Biomedical Applications

Inour ongoing efforts to develop a biocompatible adhesive forthermoplastic bonding, we have introduced a chitosan-vitaminC (CSVC) hydrogel as a non-toxic adhesive reagent for bonding poly-(methylmethacrylate) (PMMA). The bonding approach was successfully conductedusing the CSVC hydrogel assisted by mild pressure for 20 min at roomtemperature. Hydrogen bonding and ionic cross-linking between CSVCand PMMA are suggested to be the prominent chemical interactions thataccelerate the robust bonding of PMMA substrates. The hydrophilicmodifications of PMMA by the CSVC hydrogel were confirmed by watercontact angle analysis, Fourier-transform infrared spectroscopy, andscanning electron microscopy. Notably, the highest bond strength wasachieved up to 1.48 MPa with perfect bonding performance characterizedby clog-free and leak-proof microchannels. The bonded microdeviceswere applied to on-chip culturing of mesenchymal stem cells (MSCs),which can effectively promote the formation of MSC spheroids. Thus,the CSVC hydrogel is a promising nature-inspired adhesive that isexpected to give a great impulse to the development of microdevicesfor advanced biomedical applications.

Automated summary

Researchers developed a biocompatible adhesive using a chitosan-vitamin C hydrogel for bonding poly-(methylmethacrylate) substrates. Hydrogen bonding and ionic cross-linking between the hydrogel and PMMA were identified as the main chemical interactions enabling robust bonding. The modified PMMA surfaces exhibited enhanced hydrophilicity, resulting in a maximum bond strength of 1.48 MPa and leak-proof microchannels. The adhesive was successfully applied in the on-chip culturing of mesenchymal stem cells, promoting the formation of MSC spheroids.