Development and evaluation of 3D-printed ocular insert containing liposomal moxifloxacin

Conventional ocular formulations of moxifloxacin (MOX) are inefficient at maintaining an effective concentration of the drug in the tear film due to anatomical and physiological barriers of the ocular globe. In this project, 3D-printed inserts containing liposomal moxifloxacin (SL: MOX) were developed to increase ocular contact time and penetration of drugs. Moxifloxacin was encapsulated into lecithin liposomes (SL: MOX) with an efficiency of 80 %; the size was 150 nm as measured by Dynamic Light Scattering (DLS). An ex vivo study evaluated the antibacterial susceptibility of the MOX, SL: MOX, and a marketed product. Ocular inserts were then formulated and optimized as sodium hyaluronate (NaH) base hydrogels, which were prepared by an extrusion-based 3D printing technique. The process yielded inserts of uniform size, shape, and thickness, and no specific interactions between the drug and matrix were detected by FTIR and SEM. At 30 min, the in vivo drug release was 71.2 % in SL: MOX inserts (10 layers) with zero order kinetics, which was slightly greater than in MOX inserts. The inclusion of liposomes increased the solubility of MOX, and the 3D-printed insert had a significantly slower release of the drug compared to the control. The 3D printer produced ocular inserts (MOX and SL: MOX) with high content uniformity and stability, while also slowing release by incorporation of liposomal moxifloxacin. 3D printing can serve as a starting point for personalized ocular medicines focusing on patient-specific ocular conditions.