Early Detection of Hypertension Made Possible by New Technique Using Silver Nanoparticles

Russian researchers recently developed a new mechanism for the early detection of hypertension by applying surface-enhanced Raman spectroscopy powered by silver nanoparticles.

The new tool is used to detect hyper-induced molecular changes in blood cells at the disease's early stages, a Phys.org report said.

Essentially, cardiovascular diseases are the leading cause of death worldwide. Hypertension, also known as high blood pressure, is one of the essential risk factors for CVDs, resulting in organ hypoxia and consequent damage like stroke, heart failure, vasculopathy, and nephropathy.

Hypoxic Conditions Possible to Develop

Hypoxic conditions can develop as the result of hypertension-induced alterations in vessel structure or irregular changes in the affinity of hemoglobin for oxygen, leading to the reduced ability of hemoglobin to transport and emit oxygen in peripheral tissues.

Identification and monitoring of such alterations at the cellular level could help develop new tools for early diagnostics and personalized targeted therapeutics.

A team of researchers from NUST MISIS, Moscow State University, Moscow Institute of Physics and Technology, and the University of Copenhagen has proposed a new technique for selective research on the hemoglobin in erythrocytes with SERS utilizing a colloidal solution of silver nanoparticles, as well as silver nanostructured surfaces.

The nanostructured surfaces were attained by dissolving 0.3 grams of silver nitrate in 40 milliliters of water and adding 30 milliliters of 20 percent sodium hydroxide solution.

Plasmonic SERS Nanosensors Applied

The resulting substance was then washed, adding five milliliters of 25 percent aqueous ammonia and 25 milliliters of water.

Then, the obtained solution was sprayed onto the surface of coverslips and subjected to heat therapeutics. Such nanostructures enabled the team to enhance the Raman scattering from molecules close to the nanostructure surface, noted Professor Georgi Maksimov from the Materials Physics Department at the University MISIS.

In the study published in the Biosensors journal, the study investigators applied plasmonic SERS nanosensors, detailed in a report published in Biosensors and Bioelectronics journal, to examine changes in the properties of erythrocytes in normotensive and hypertensive mouse models.

As a result, they could detect changes in erythrocyte properties in hypertensive mice, like a reduction in the erythrocyte plasma membrane fluidity.

One of this phenomenon's explanations is the increased cholesterol level—rising cholesterol results in a reduction in membrane fluidity and changes in erythrocyte function.

Addressing Damage to Oxygen

For the first time, the researchers observed a drop in the in-plane mobility of heme in hemoglobin in hypertensive mice, which is impossible to detect using other approaches.

They believe this can be explained by the rising stiffness of the membrane, which may reduce the ability of heme to adjust to changing oxygen concentrations and impact hemoglobin's affinity to oxygen.

That, in turn, can damage the oxygen supply to tissues in hypertensive conditions. The proposed SERS-based technique may be employed to develop novel diagnostic tools for detecting early pathologies and to analyze treatment outcomes in CVD and beyond.

Related information about silver nanoparticles is shown on Risk Bites' YouTube video below:

Check out more news and information on Nanoparticles in Science Times.