Design, Manufacturing and Physicochemical Validation of a New Biodegradable Intraurethral Device for Post-Operative...

Urethral stricture is the narrowing of the urethra caused by the growth of aberrant tissue after an injury. Actual post-operative treatment requires the placement of a Foley catheter for external urinary drainage after surgery. However, it requires a second intervention for removal, and the contact with the external environment and non-biodegradable composition even aggravates urinary tract infections (UTIs) in 7.12% of patients. Thus, we developed a completely biodegradable intraurethral device (BID) as an alternative to catheterization. BID is a continuous-walled hollow tubular stent with outer wall corrugations composed of poly(d,l-lactide-co-ε-caprolactone) copolymer synthesized by ring-opening polymerization, using a bismuth-based catalyst. Complying with EU Medical Device Regulation 2017/745, BID was manufactured by injection molding following ISO 13485 and irradiated by e-beam, according to ISO 11137 and 11737. Physico-chemical characterization was evaluated following ISO 10993, showing a scalable synthetic procedure with reproducible composition, high molecular weight, adequate thermal properties, and metal content below its cytotoxic level. Scanning electron microscopic analysis confirmed consistent dimensions and no detrimental effect in the device after irradiation. Additionally, hydrolytic degradation studies (static and dynamic) showed complete degradation of BID after 90 days, obtained by the tailored composition of the synthesized copolymer and aligned with the tissue regeneration process. Mechanical properties confirmed a consistent tubular shape up to 28 days and no migration of the device even at a maximum urine flow of 1500 mL/min thanks to the tailored corrugated design of BID. These findings position BID as a promising alternative in post-operative urethral stricture management, addressing critical limitations of current practices. Hopefully, our BID might provide a biodegradable solution, minimizing UTIs and migration, and eliminating the current second intervention for catheter removal.