In a scientific study, Iranian researchers have developed a gene biosensor capable of quickly and accurately diagnosing the presence of an important bacterium in human blood plasma, effective in production of various infectious diseases, thereby helping to provide early treatments.
Bacteria known as Haemophilus influenza is a gram-negative coccobacillus characterized by the production of a capsule of polysaccharide. It has more aggressive properties than non-encapsulated strains and causes various respiratory infections such as sinusitis, acute otitis media, pneumonia and bronchitis. The bacteria in more aggressive conditions can cause other diseases such as cellulite, septic arthritis and even meningitis. Therefore, quick and sensitive detection of these bacteria is of great importance in medical microbiology.
There are several methods for doing this, including laboratory culture, LAT or latex particle agglutination, and PCR or polymerase chain reaction. But each of these methods has problems and limitations such as being time consuming, low specificity and sensitivity, the need for specialized people as well as the need for expensive and advanced equipment. Therefore, researchers have always been looking for new approaches to effectively detect viruses and bacteria, and in this way, the use of biosensors has gained a special place.
To this end, a team of Iranian researchers have conducted a study in which a genomic biosensor, or so-called genosensor, has been invented and successfully used to detect Haemophilus influenza.
In this study, recently published in the prestigious International Journal of Biological Macromolecules, a DNA-based bioassay was used to monitor the bacterial genome in human plasma samples using pDNA and cDNA binding. In this bioassay, DNA hybridization strategies have been used to investigate the binding of DNAs.
To do this, researchers from the Urmia University and Tabriz University of Medical Sciences, in collaboration with the Palacky University Olomouc of Czech Republic, synthesized and deposited certain inks functionalized by D-penicillamine, known as Ag NPs-DPA-GQDs on the surface of glass carbon electrodes (GCE).
The researchers used gold and silver nanoparticles to make the inks mentioned, and then examined the morphology of the particles in the ink solution using TEM and SEM electron microscopy.
The results of the study showed that this platform promisingly has the potential to be used in diagnosis of H. Influenzae in clinical samples.
“Our evaluations showed that the engineered genosensor in this study could yield good specificity and high sensitivity for the diagnosis of Haemophilus influenza genome”, mentioned by Nasrin Shadjou, a researcher at the Department of Nanotechnology, Faculty of Science and Chemistry, Urmia University and three other colleagues. “Under optimal conditions, linear range and low limit of quantitation (LLOQ) were obtained at target concentrations”.
They’ve reported: “The designed biosensor also showed high capability of discriminating one-base, two-base and three-base mismatched sequences and could be also easily regenerated and reused to evaluate hybridization process”.
Now, along with biosensors previously developed for rapid and exact diagnosis of various infectious diseases such as E. coli infection, cholera, syphilis, Salmonella infection, AIDS, tuberculosis and dengue fever, this innovation by Iranian experts can be widely used to optimally diagnose Haemophilus. Influenza in blood samples.
Author: Mohammadreza Delfieh