%0 PDF %T An Encrustation Model for Urinary Catheter Assessments %A Li, Gary. %D 2017-06-29T09:04:37.223-04:00 %8 2017-07-07 %R http://localhost/files/bk128p037 %X Abstract: Patients requiring long term urinary catheterization suffer from encrustation and catheter blockage, issues associated with urinary tract infections, urine reflux, and kidney failure. The encrustation model developed here establishes a high-throughput assay to evaluate comparative encrustation formation as a function of different substrates and surfaces. This design uses a peristaltic pump to continuously cycle artificial urine through a bioreactor that houses twelve hanging catheter samples. Moreover, a separate pump line introduces urease to mimic Proteus mirabilis production of urease. The system produces measurable encrustation within 1.5 hours and showed further encrustation growth as a function of solution refreshments and time. Confocal microscopy, scanning electron microscopy, energy-dispersive x-ray spectroscopy, and attenuated total reflectance Fourier transform spectroscopy analysis confirmed the formation of struvite and apatite. All encrustations were dissolved in acid and quantified using the Calcium o-Cresolphthalein Complexone protocol, a calcium colorimetric assay. Consistency of encrustation formation between sample positions and along sample lengths was evaluated. Subsequently, the effects of surface roughness, radiopacifiers, surface charge, and substrate material on encrustation was evaluated using the encrustation assay. The results showed that polyether and polyester polyurethanes had greater calcium encrustation resistance compared to silicone (p < 0.001), a commonly used material for long-term bladder catheterization, and the polycarbonate polyurethane control (p < 0.001). No statistical difference was found between samples with barium sulfate and without barium sulfate; samples coated with polyelectrolytes and uncoated samples; and a 4.6x rougher surface and control. The material comparison study provided valuable information for developing next-generation catheters that resist catheter-associated complications.; Thesis (M.S.)--Tufts University, 2017.; Submitted to the Dept. of Biomedical Engineering.; Advisors: Jonathan Zhang, and David Kaplan.; Committee: Qiaobing Xu.; Keywords: Biomedical engineering, and Engineering. %[ 2022-10-12 %9 Text %~ Tufts Digital Library %W Institution