Multifunctional Paper-Based Analytical Device for In Situ Cultivation and Screening of Escherichia coli Infections

Abstract

Point-of-care testing (POCT) for uropathogen detection and chemical screening has great benefits for the diagnosis of urinary tract infections (UTIs). The goal of this study was to develop a portable and inexpensive paper-based analytical device (PAD) for cultivating bacteria in situ and rapidly testing for nitrite on the same device. The PAD was fabricated using a wax printing technique to create a pattern on Whatman No. 1 filter paper, which was then combined with a cotton sheet to support bacterial growth. Nitrite detection was based on the principle of the Griess reaction, and a linear detection range of 0–1.6 mg/dL (R2 = 0.989) was obtained. Scanning electron microscopy (SEM) analysis demonstrated that the bacteria were able to grow and formed a cluster on the cellulose fibres within 2 hours. The enzyme β-glucuronidase, which is specifically produced by Escherichia coli, was able to convert the pre-immobilized 5-bromo-4-chloro-3-indolyl-β-D-glucuronide sodium salt (X-GlcA), a colourless substrate, generating a blue colour. Under optimum conditions, the proposed device allowed bacterial concentrations in the range of 104–107 colony forming units (CFU)/mL to be quantified within 6 hours. Moreover, the use of this device enables the identification of E. coli pathogens with selectivity in real urine samples. In conclusion, the PAD developed in this study for UTI screening provides a rapid, cost-effective diagnostic method for use in remote areas.

Lab-on-Paper Devices for Diagnosis of Human Diseases Using Urine Samples—A Review

“…However, in some cases, the bacteria may remain in the urinary system and cause infection [124,125]. In fact, most urinary tract infections (UTI) are caused by Escherichia coli (E. coli) [126][127][128], which normally appears in the rectum. Consequently, several lab-on-paper platforms aimed at the detection of E. coli in urine have been proposed in recent years [125][126][127][128][129].…”

“…In fact, most urinary tract infections (UTI) are caused by Escherichia coli (E. coli) [126][127][128], which normally appears in the rectum. Consequently, several lab-on-paper platforms aimed at the detection of E. coli in urine have been proposed in recent years [125][126][127][128][129]. For example, Gumustas et al [125] proposed a paper-based test strip for the sensitive detection and quantification of E. coli in urine samples by means of SERS-based and colorimetric lateral flow immunoassay (LFIA) techniques.…”

Biomarker discovery and beyond for diagnosis of bladder diseases

“…In 2015, a team of biomedical engineers at the University of Arizona was able to develop a highly-sensitive and cost-efficient paper-based analytical device (μPad) that could monitor urine for urinary tract infection (UTI) and gonorrhea [ 46 ]. A recent study developed a similar device that quantified β-glucuronidase, an enzyme released by 95% of E. coli , the bacteria that causes UTI [ 47 ]. In addition to these urinalysis-based detection devices, several others have been developed to detect other compounds.…”

Paper-Based Device for First Level Screening of Nitric Oxide in Saliva of Caries Active and Caries Free Children

“…Institutional Human Ethics Committee of Chettinad Academy of Research & Education (CARE) approved the study (Proposal No: 156/IHEC/ [12][13][14][15][16]. Children between the age group of 6-12 years of Caries active and Healthy participants were selected.…”

“…11 In 2018, researchers could fabricate a paper-based device for the simultaneous detection of pH and nitrate. 12 The health of the population can be monitored by analyzing biological uids; however, in rural regions with less industrialization, under emergency circumstances or a personalized home check, this becomes di cult. Though regular laboratory type of equipments or instruments provide measurements that are quantitative of analytes present in biological samples under emergency and stressful situations, they are not apt as the need for trained personnel or expensive tools or the need for a considerable amount of biological samples.…”