Carbon Nanotube–Liposome Complexes in Hydrogels for Controlled Drug Delivery via Near-Infrared Laser Stimulation

Externally controllable drug delivery systems are crucial for a variety of biological applications where the dosage and timing of drug delivery need to be adjusted based on disease diagnosis and progression. Here, we have developed an externally controllable drug delivery system by combining three extensively used platforms: hydrogels, liposomes, and single-walled carbon nanotubes (SWCNTs). We have developed carbon nanotube–liposome complexes (CLCs) and incorporated these structures into a 3D alginate hydrogel for use as an optically controlled drug delivery system. The CLC structures were characterized by using a variety of imaging and spectroscopic techniques, and an optimal SWCNT/lipid ratio was selected. The optimal CLCs were loaded with a model drug (FITC-Dex), incorporated into a hydrogel, and their release profile was studied. It was shown that release of the drug cargo can be triggered by using an NIR laser stimulation tuned to the optical resonance of a particular SWCNT species. It was further shown that the amount of released cargo can be tuned by varying the NIR stimulation time. This system demonstrates the externally controlled delivery of drug cargo and can be used for different applications including cancer chemotherapy delivery.