<scp>3D</scp> Printing Mesoporous Silica Nanoparticles/ <scp>PCL</scp> With Controlled Drug Release for Pet Deworming

ABSTRACT In this study, a polycaprolactone (PCL)‐based drug‐eluting pet collar was successfully fabricated utilizing fused granulate fabrication (FGF) 3D printing technology to deliver sustained‐release deworming treatment for pets. Initially, mesoporous silica nanoparticles (MSNs) were synthesized and carboxyl‐functionalized via a soft‐templating method, significantly enhancing the drug loading capacity and stability of amitraz (AMZ). Through a temperature‐recrystallization approach, the integration of carboxyl‐modified mesoporous silica (AC‐MSNs) with AMZ achieved 33.55% drug loading and substantially enhanced both drug loading capacity and efficacy against Ctenocephalides felis . Subsequently, AMZ‐loaded AC‐MSNs were compounded with PCL via twin‐screw melt extrusion to produce drug‐loaded pellets for FGF 3D printing, and pet collars were fabricated accordingly. The mechanical properties of PCL‐based composites were enhanced after incorporation of drug and MSNs, with orientation in the [90, 90] direction yielding optimal mechanical strength. In vitro CCK‐8 cytotoxicity assays confirmed &gt; 96% cell viability, demonstrating the biocompatibility of the fabricated composites. Animal studies ( n = 1 per group) further validated the efficacy of the sustained‐release collars, showing complete elimination of Ctenocephalides felis (cat flea) in the experimental animal by Day 7 with no recurrence through Day 28, comparable to the positive control (fipronil), while blood biochemistry remained within normal ranges. However, this proof‐of‐concept study employed nonblinded comb‐counting assessment without inferential statistical analysis, precluding definitive clinical efficacy claims. These preliminary observations justify future scaled studies ( n ≥ 6 per group, randomized, blinded) to establish therapeutic efficacy and safety profiles. This study presents an innovative FGF 3D printing‐based solution for pet deworming, demonstrating technical feasibility while holding potential for future clinical application upon further validation.