Bioactive micropatterning of apatite immobilizing cell adhesion protein by laser-induced forward transfer with a shock absorber

The additive patterning of apatite with good biocompatibility and osteoconductivity is a useful technique for the production and surface functionalization of biomaterials. We developed this technique through our laser-induced forward transfer (LIFT) process using a laser-absorbing sacrificial layer in combination with a shock-absorbing polydimethylsiloxane (PDMS) receiver. With the PDMS shock-absorbing function, even the brittle apatite and that immobilizing the cell adhesion protein fibronectin (Fn-apatite) were successfully transferred and micropatterned while maintaining their dense, filmy state. The laser pulse energy effect was investigated, leading to the optimum energy range just above the transfer threshold. The apatite and Fn-apatite micropatterns exhibited superior cytocompatibility compared to the PDMS surface, and could potentially be used for cellular micromanipulation.