3D DLP-printed cannabinoid microneedles patch and its pharmacokinetic evaluation in rats

The objective of the present study was to enhance the bioavailability of cannabidiol (CBD) using 3D Digital Light Processing (DLP)-printed microneedle (MN) transdermal drug delivery system.

CBD MN patch was fabricated and optimized using 3D DLP printing using CBD (8% w/v), Lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) (0.49% w/v), distilled water (20% w/v), and poly (ethylene glycol) dimethacrylate 550 (PEGDAMA 550) (up to 100% w/v). CBD MNs were characterized for their morphology, mechanical strength, in vitro release study, ex vivo permeation study, and in vivo pharmacokinetic (PK) profile.

Microscopic images showed that sharp CBD MNs with a height of ~800 microm, base diameter of ~250 microm, and tip with a radius of curvature (RoC) of ~15 microm were successfully printed using optimized printing parameters. Mechanical strength studies showed no significant deformation in the morphology of CBD MNs even after applying 0.5N/needle force. Ex vivo permeation study showed significant (P < .0001) permeation of CBD in the receiving media as compared to CBD patch (control). In vivo PK study showed significantly (P < .05) enhanced bioavailability in the case of CBD MN patch as compared to CBD subcutaneous inj. (control).

Overall, systemic absorption of CBD was significantly enhanced using 3D-printed MN drug delivery system.