Hydrophilic inflatable penile prosthesis surface coatings readily rebind antibiotics and maintain antimicrobial efficacy ex vivo

Hydrophilic penile prosthesis (PP) surfaces removed during revision surgery may potentially rebind antiseptics and maintain antimicrobial efficacy ex vivo. Coloplast Titan reservoirs and cylinders were retrieved during revision surgery for mechanical failure. Congo Red staining and contact angle measurements were performed to evaluate the integrity of the hydrophilic surface. Fluorescent antibiotic binding was performed by submerging discs for 3 min in either fluorescein-isothiocyanate (FITC) labeled or unlabeled vancomycin at 2 mg/mL. Fluorescence was quantified via ImageJ. 8 mm discs were submerged for 3 min in normal saline (NS), 0.05% chlorhexidine gluconate, or a 2 mg/mL vancomycin and 160 μg/mL gentamicin (VG) antibiotic, then incubated with 10⁵ colony-forming units per milliliter of methicillin-sensitive Staphylococcus aureus ATCC25923 for 48 h then counted. Mann-Whitney U and one-way ANOVA tests were performed to compare outcomes, p < 0.05 considered significant. All PP tested for binding with FITC-vancomycin showed significant increases in fluorescence relative to unlabeled vancomycin controls (p < 0.0001). All explanted and control PP exhibited significant decreases in bacterial counts on VG-treated surfaces relative to NS controls (p < 0.01). The hydrophilic surface of the reservoir and cylinders maintain their integrity based on Congo Red staining and rebind VG antibiotics effectively based on microbiology and fluorescent binding studies.