Electrokinetic stringency control in self-assembled monolayer-based biosensors for multiplex urinary tract infection diagnosis, "Beyond the Abstract," by Joseph C. Liao and Pak Kin Wong

BERKELEY, CA (UroToday.com) - Urinary tract infection (UTI) is the most common bacterial infection and accounts for millions of office visits and hospital admissions each year. In current practice of UTI diagnosis, time-consuming and labor-intensive pathogen identification and antimicrobial susceptibility testing (AST) procedures are performed to identify bacterial pathogens and their resistances. The results are typically available 2-3 days after sample collection. The lack of rapid diagnosis of bacterial pathogens in patient samples leads to the overuse and misuse of broad-spectrum antibiotics, which cause the rapid emergence of multi-drug resistant pathogens. As a consequence, many pharmaceutical companies have deemphasized their antibiotic development programs due the poor investment return, and only few antibiotics have been developed in the past decade. This represents a significant threat in public health and a major global health challenge.

Rapid diagnosis of infectious diseases represents a major step in improving clinical decision making and expediting delivery of appropriate treatment. Despite the recent advancement of micro-fluidics and nanotechnology, the approach for UTI diagnosis is fundamentally unchanged in the past decades. Biosensor technologies that are rapid, low cost, and portable, represent promising alternatives to the current culture based techniques for infectious disease diagnosis. Rapid UTI diagnostics using biosensor technologies, however, could be hindered by the challenges of matrix effect in physiological samples, cross-talk between similar species, and non-specific binding of the molecular probes.

Our team has published a series of articles that demonstrate biosensor-based UTI diagnostics, including both pathogen identification and AST. In this work, we address two fundamental challenges, including matrix effects and nonspecific binding, in biosensor-based infectious disease diagnostics by incorporating electrokinetic stringency control in a self-assembled monolayer-based electrochemical biosensor. The ability to significantly reduce the matrix effect and improve the sensor specificity represents key steps of realizing biosensor technologies in UTI diagnostics. Furthermore, the electrochemical sensor and electrokinetic technology are highly portable platforms, taking advantage of the rapid development of microelectronics that drives the breakthroughs in CCD cameras, smart phones, and tablets. Integrating these technologies into to a fully automated system will enable point of care diagnostics of UTI, which may revolutionize the current practice.

Additional information of our work can be found in our laboratory and Facebook pages:


Written by:
Joseph C. Liaoa and Pak Kin Wongb as part of Beyond the Abstract on UroToday.com. This initiative offers a method of publishing for the professional urology community. Authors are given an opportunity to expand on the circumstances, limitations etc... of their research by referencing the published abstract.

a Department of Urology, Stanford University, Stanford, CA 94304 USA
b Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721 USA

Electrokinetic stringency control in self-assembled monolayer-based biosensors for multiplex urinary tract infection diagnosis - Abstract

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