Formation of crystalline biofilms following infection by Proteus mirabilis can lead to encrustation and blockage of long-term indwelling catheters, with serious clinical consequences. We describe a simple sensor, placed within the catheter drainage bag, to alert of impending blockage via a urinary color change. The pH-responsive sensor is a dual-layered polymeric “lozenge”, able to release the self-quenching dye 5(6)-carboxyfluorescein in response to the alkaline urine generated by the expression of bacterial urease. Sensor performance was evaluated within a laboratory model of the catheterized urinary tract, infected with both urease positive and negative bacterial strains under conditions of established infection, achieving an average “early warning” of catheter blockage of 14.5 h. Signaling only occurred following infection with urease positive bacteria. Translation of these sensors into a clinical environment would allow appropriate intervention before the occurrence of catheter blockage, a problem for which there is currently no effective control method.

中文翻译：

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感染响应荧光传感器的开发，用于尿道阻塞的早期检测

奇异变形杆菌感染后形成结晶生物膜可能会导致长期留置导尿管结垢和阻塞，并带来严重的临床后果。我们描述了一个放置在导管引流袋内的简单传感器，用于通过尿液颜色变化来提醒即将发生的阻塞。pH响应传感器是双层聚合物“锭剂”，能够响应细菌尿素酶表达产生的碱性尿液释放自淬灭染料5（6）-羧基荧光素。在导管尿道的实验室模型中评估了传感器的性能，该导管模型在确定的感染条件下同时感染了尿素酶阳性和阴性细菌菌株，从而实现了平均14.5 h的“早期预警”导管阻塞。仅在尿素酶阳性细菌感染后才发出信号。