A capacitive touch screen sensor for detection of urinary tract infections in portable biomedical devices.

Carlos Honrado,Tao Dong

doi:10.3390/s140813851

Abstract

Incidence of urinary tract infections (UTIs) is the second highest among all infections; thus, there is a high demand for bacteriuria detection. Escherichia coli are the main cause of UTIs, with microscopy methods and urine culture being the detection standard of these bacteria. However, the urine sampling and analysis required for these methods can be both time-consuming and complex. This work proposes a capacitive touch screen sensor (CTSS) concept as feasible alternative for a portable UTI detection device. Finite element method (FEM) simulations were conducted with a CTSS model. An exponential response of the model to increasing amounts of E. coli and liquid samples was observed. A measurable capacitance change due to E. coli presence and a tangible difference in the response given to urine and water samples were also detected. Preliminary experimental studies were also conducted on a commercial CTSS using liquid solutions with increasing amounts of dissolved ions. The CTSS was capable of distinguishing different volumes of liquids, also giving an exponential response. Furthermore, the CTSS gave higher responses to solutions with a superior amount of ions. Urine samples gave the top response among tested liquids. Thus, the CTSS showed the capability to differentiate solutions by their ionic content.

Highlights

Incidence of urinary tract infections (UTIs) is only second in frequency when compared to incidence of upper respiratory infections
Given the results shown from this device, implementation of a touch screen based UTI detection device can prove to be a highly sensitive tool
A correlation between the small capacitance differences measured in the simulation and the obtained Raw Count Difference (RCD) can be made, with the capacitive touch screen sensor (CTSS) proving to be able to detect these minor changes in capacitance and give a definite differentiated response. These results prove that the CTSS gives a greater response to solutions with a superior amount of ions, being capable of distinguish between solutions by their ionic content

Summary

Introduction

Incidence of urinary tract infections (UTIs) is only second in frequency when compared to incidence of upper respiratory infections. Whereas most upper respiratory infections have a viral etiology (and so require little to none medical intervention), UTIs are mainly caused by enteric bacteria. UTIs can be caused by viral or fungal infections [2]. Other groups of bacteria as Klebsiella, Proteus, Pseudomonas, and Enterobacter can cause UTI but are typically related to abnormalities of the urinary system or urinary catheterization [3]. Antimicrobial therapy is needed to eliminate the infecting organisms and an early detection of the infection can help prevent more severe sequelae [4,5]

Methods

Results

Conclusion