We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
PURITAN MEDICAL

Download Mobile App




Events

09 Apr 2024 - 12 Apr 2024
15 Apr 2024 - 17 Apr 2024
23 Apr 2024 - 26 Apr 2024

Biosensor-Based Rapid Urine Test Detects Urogenital Schistosomiasis

By LabMedica International staff writers
Posted on 14 Jul 2015
Print article
Image: Egg of Schistosoma haematobium in a wet mount of urine concentrates, showing the characteristic terminal spine (Photo courtesy of Centers for Disease Control and Prevention).
Image: Egg of Schistosoma haematobium in a wet mount of urine concentrates, showing the characteristic terminal spine (Photo courtesy of Centers for Disease Control and Prevention).
In infrastructure-limited regions, point-of-care (POC) molecular diagnostics hold the potential to transform the management of infectious diseases such as schistosomiasis that carry significant long-term morbidity if left undiagnosed.

Electrochemical biosensors are well suited for molecular diagnostics because of their high sensitivity, low cost, ease of integration into POC devices, and portability of the reader instrumentation and have now been used to detect urogenital schistosomiasis.

Scientists at Stanford University School of Medicine (CA, USA) and their colleagues have developed a strategy for a rapid one hour molecular diagnosis of bacterial urinary tract infections using electrochemical biosensors. Urinary cells are lysed and directly applied to an array of sensors functionalized with oligonucleotide probes targeting the 16S ribosomal ribonucleic acid (rRNA) of common uropathogens. Formation of the sequence-specific hybridization complex between the pathogen rRNA and the labeled capture and detector probe pairs is detected by an enzyme tag that mediates an amperometric signal output.

The biosensor is composed of three planar gold electrodes, one each for working, auxiliary, and reference. For the biosensor assay, capture probes are bound to the surface of the working electrode via a thiol linkage. Cells in the sample are lysed and mixed with a buffered solution of detector probe, then applied to the sensor surface. If the target rRNA is present, a hybridization complex of target, capture, and detector probes forms. This complex is detected by binding of horseradish peroxidase (HRP)-conjugated anti-fluorescein binding to a fluorescein tag on the detector probe and addition of tetramethylbenzidine (TMB) substrate. The electron transport mediated by the HRP is measured amperometerically, and the signal is proportional to the quantity of the target.

By inducing bulk fluid motion and local heating, alternating current (AC) electrokinetics improved overall signal-to-noise of the biosensor assay. Further implementation of electrokinetics will facilitate integration into a POC device as it obviates the need for an external incubator for hybridization. For schistosomal detection, the scientists applied square wave AC potential across the working and auxiliary electrodes of the electrochemical sensors using a function generator.

The authors concluded that they have made an important step toward development of a POC device for rapid detection of Schistosoma haematobium eggs in urine. They have implemented strategies that will aid in device integration, such as mechanical lysis and AC electrokinetics. For future development, they will integrate this core assay into a fully automated microfluidics cartridge, further optimize the detection sensitivity, and validate with clinical samples.

Related Links:

Stanford University School of Medicine



Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Specimen Collection & Transport
Anti-Cyclic Citrullinated Peptide Test
GPP-100 Anti-CCP Kit
New
Gold Member
TORCH Panel Rapid Test
Rapid TORCH Panel Test

Print article

Channels

Clinical Chemistry

view channel
Image: Reaching speeds up to 6,000 RPM, this centrifuge forms the basis for a new type of inexpensive, POC biomedical test (Photo courtesy of Duke University)

POC Biomedical Test Spins Water Droplet Using Sound Waves for Cancer Detection

Exosomes, tiny cellular bioparticles carrying a specific set of proteins, lipids, and genetic materials, play a crucial role in cell communication and hold promise for non-invasive diagnostics.... Read more

Molecular Diagnostics

view channel
Image: The cobas Malaria test is the first FDA-approved molecular test to screen U.S. blood donors for malaria (Photo courtesy of Roche)

First FDA-Approved Molecular Test to Screen Blood Donors for Malaria Could Improve Patient Safety

Malaria, a serious illness that often leads to death, is spread by a specific mosquito species that infect humans with a parasite. Other transmission modes include blood transfusions, organ transplants,... Read more

Hematology

view channel
Image: The low-cost portable device rapidly identifies chemotherapy patients at risk of sepsis (Photo courtesy of 52North Health)

POC Finger-Prick Blood Test Determines Risk of Neutropenic Sepsis in Patients Undergoing Chemotherapy

Neutropenia, a decrease in neutrophils (a type of white blood cell crucial for fighting infections), is a frequent side effect of certain cancer treatments. This condition elevates the risk of infections,... Read more

Pathology

view channel
Image: The medical office procedure detects the key biomarker in Parkinson’s and related neurodegenerative diseases (Photo courtesy of BIDMC)

Simple Skin Biopsy Test Detects Parkinson’s and Related Neurodegenerative Diseases

Parkinson's disease and a group of related neurodegenerative disorders known as synucleinopathies impact millions globally. These conditions, including Parkinson’s disease (PD), dementia with Lewy bodies... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.