Phenylboronic acid-functionalized photothermal nanofibers for enhanced suspension cell adhesion and intracellular...

The development of advanced photoporation-mediated intracellular delivery platforms for suspension cells offers significant potential for biomedical applications, particularly in cell-based therapies. However, critical challenges remain in improving suspension cell adhesion to delivery substrates and optimizing intracellular delivery efficiency. Here, a phenylboronic acid-functionalized photothermal electrospun nanofiber (PPEN) substrate is demonstrated for efficient suspension cell adhesion and intracellular delivery. PPENs are synthesized through electrospinning with embedded iron oxide nanoparticles (IONPs) to enhance photothermal effects, followed by surface functionalization with boronic acid groups to improve cell adhesion. A systematic evaluation reveals optimal adhesion performance under specific modification and incubation conditions. PPENs achieve a 2.6-fold enhancement in intracellular delivery efficiency of the 10 kDa fluorescein isothiocyanate (FITC)-dextran (FD10) biological macromolecule during photoporation with Jurkat suspension cells, optimized at an IONP concentration of 2 wt% and a laser fluence of 0.30 J cm^-2. Additionally, PPEN photoporation enables effective FD10 loading at low laser fluence and controlled molecule release at high laser fluence, highlighting the dual functionality of engineered red blood cells as delivery vehicles and release platforms. These findings underscore the potential of PPENs as a versatile platform for advancing precision therapeutics and cell-based therapies by enhancing suspension cell adhesion and intracellular macromolecule delivery.