Typically, these samples need to be cleaned and diluted prior to analysis, and current medical diagnostic techniques rely on healthcare facilities and laboratories to perform these routine analyses. .
This is a lengthy process that requires trained personnel and expensive instrumentation to extract, transport, store, process and analyze samples in centralized locations. Furthermore, in times of global crisis like the ongoing pandemic, the pressure of thousands of analytical requests can saturate and collapse the healthcare system.
Point-of-care devices, on the other hand, are small automated tools that are capable of performing diagnostics in decentralized locations and can provide quick answers. An example of such a device is a glucose meter that people with diabetes use to monitor their blood sugar levels.
These devices can overcome the inherent limitation of having to process samples through a centralized system, allowing anyone to monitor their health at home, using just a single blood sample. small is extracted by fingerprint.
However, the development of these devices has been burdened by technical challenges associated with the measurement of biological samples.
Biomarkers for some diseases and infections are present in samples only in very small amounts, thus posing a challenge to develop extremely sensitive detection techniques.
While increasing the surface area of a biosensor can increase device sensitivity, these surfaces tend to quickly become clogged and contaminated, rendering them unusable.
To this end, a research team led by Professor CHO, Yoon-Kyoung at the Center for Soft and Living Matters of the Institute of Basic Sciences (IBS) in Ulsan, South Korea recently developed a sensor biotransformation using methods to generate nano and nanostructured surfaces.
This combined strategy not only provides the sensor with unmatched sensitivity, but also makes it resistant to protein fouling.
Although there was no previously known method to reliably generate electrodes using such nano and nanostructured substrates, the team reported a simple method. simple to create such materials.
The mechanism is based on the application of electrical pulses to a flat gold surface in the presence of sodium chloride and a surfactant that can form micelles in solution. These electrical pulses drive the response appropriately to etch and separate the gold from the surface, and in turn, grow nanostructures and form nanopores (Figure 1).
The use of a surfactant in the form of micelles is essential to the success of this strategy as it prevents the corroded material from diffusing away during the process, so it can be reattached. .
The formation of these nanostructures provides a large surface area, which is beneficial for increasing the sensitivity of the assays, while the formation of nanopore substrates is ideal for preventing contamination from the samples. biological.
Both the nanostructure and the combined benefit of the nanopore are key to the success of this strategy, which can be applied to the direct analysis of clinical plasma samples.
The researchers further demonstrated this new technology by building a biosensor to detect prostate cancer. The electrode is sensitive enough to distinguish between a group of prostate cancer and healthy donors using only a small amount of plasma or urine sample.
No dilution or pretreatment steps are used, meaning the technology can easily be used to diagnose cancer at the point of care.
Professor Cho stated, “We believe this technology is essential for the future development of point-of-care devices and diagnostic tests that work with biological samples. diagnose cancer, pathogens and other diseases.”