Scientists use Nano-Biosensors for the Rapid Detection of Influenza

Scientists use Nano-Biosensors for the Rapid Detection of Influenza

By Areeba Majeed (BS Biotechnology)

https://www.nanowerk.com/nanotechnology-news/newsid=41854.php

Ever wondered in every flu season when you get infected and developed symptoms of flu about how the disease could somehow have been detected before the onset of symptoms? How the entire situation of developing flu could have been prevented? Seems a bit unreal at first, because the commonly used viral culture tests provide results in 3-10 days which is not helpful in early detection of influenza because on average, the incubation period for the flu is for two days. This means that, on average, people start to develop flu symptoms about two days after coming into contact with the influenza virus which is before the test results can even come in.

But now with advancements in science and technology, scientists have developed rapid influenza diagnostic tests (RIDTs) using nano-bio-sensors and have made the rapid detection of influenza possible even before its symptoms occur.

Before going into the details of how these nano-bio-sensors provide rapid detection of influenza virus? We will have to understand what influenza is and how it is caused as well as what nano-bio-sensors are and how they work to provide rapid detection?

What is influenza and how is it caused?

Influenza “commonly known as flu” is a viral infection. It attacks the respiratory system and its main targets are the nose, throat, and lungs. It is caused by the influenza virus. Influenza virus categorized into three species, A, B and C out of which influenza A and B viruses lead to epidemic influenza (seasonal). These viruses travel through the air in droplets when someone with the infection cough, sneeze or talk. Which then can get transferred to eyes, nose or mouth of healthy people thereby infecting them as well. New strains of influenza virus appear regularly and these strains are constantly changing. So, if a person has had influenza in the past or even has been vaccinated, the new influenza strain can be very different immunologically. The one with antibodies generated from the vaccine or from being exposed to the influenza virus in the past will not be able to fight and provide protection against the new influenza strains.

Image: https://www.news-medical.net/health/What-is-Influenza.aspx

What are Nano-Biosensors?

The devices which are used to detect a biological analyte’s presence or concentration, such as a biomolecule, a biological structure or a microorganism are called biosensors. They consist of three parts: a component that recognizes the analyte and produces a signal, a signal transducer, and a reader device. Biosensors of nanoscale dimensions are called nano-bio-sensors. The devices that use an optical, electronic, or magnetic technology to measure a biochemical or biological event through a compact probe are called nano-bio-sensors. They are being widely used for molecular detection of biomarkers associated with the diagnosis of disease. They commonly comprise a biological recognition molecule immobilized onto the surface of a signal transducer.

The researchers behind this new invention

Recently, Dr Hao Jianhua and Dr Yang Mo of Hong Kong Polytechnic University jointly developed a novel nano-biosensor for rapid detection of flu. They did so because with the flu epidemic raging across the world, developing an efficient, effective and highly sensitive detection method is essential. 

Dr Hao Jianhua (left) and Dr Yang Mo (right) who have developed a nano-biosensor for rapid detection of influenza.
Image: https://www.polyu.edu.hk/cpa/excel/en/201603/research/r1/index.html

How the researchers successfully developed nano-bio-sensors and used them for the rapid detection of influenza?

The researchers used an optical method called upconversion luminescence resonance energy transfer (LRET) to form LRET-based nano-bio-sensors for ultrasensitive virus detection. Upconversion is a process where light can be emitted with photon energies higher than those of the light-generating the excitation. So, in LRET, the negatively charged gold nanoparticles (AuNPs) are used as the energy acceptors and the positively charged upconversion nanoparticles (UCNPs) as the energy donors. Then, through electrostatic interaction, they bind together. As a result of this binding, luminescence quenching is seen. This quenching is due to the luminescence resonance energy transfer from UCNPs to AuNPs.

UCNPs are nanomaterials which are lanthanide-doped. These nanoparticles convert near-infrared (NIR) radiation into visible radiation. Due to this reason, UCNPs are favourable luminescent materials in processes like bioanalysis. The AuNPs were conjugated with flu virus oligo and the UCNPs were conjugated with a probe oligo whose DNA base pairs were complementary with that of the AuNPs flu virus oligo. Due to the complementarity between the DNA base pairs, they would be drawn together due to attraction force working like magnets. This process is also called oligo hybridization. The AuNPs will absorb the green light after being illuminated by a portable near-infrared laser pen. On the other hand, the UCNPs then will emit green light which can be seen by the naked eye. The fainter the green light will be, the greater the concentration of the flu virus.

Advantages of using this new technology of Nano-Biosensors for the rapid detection of influenza

·   It involves simple operational procedures.

·    Using this technology for testing virus requires only two to three hours, making it more than 10 times quicker than the conventional method in detecting the virus.

·       Its cost is around 80% lower than traditional testing methods.

·      It does not require any expensive instruments and sophisticated operational skills, with its sensitivity comparable to traditional clinical methods.

·        It causes low damage to genetic materials and does not induce background fluorescence. 

Author’s Information

Areeba Amjad (BS biotechnology) has summarized and written this article. She was inspired by her mentor Miss Iqra Aslam (MPhil Biochemistry), Lecturer in Biochemistry at University of Management & Technology, Sialkot.

Editor and Reviewer Information

Muhammad Numan (PhD Scholar Biochemistry) has reviewed and edited this article.

References

All the resources which were used to write this article are given in this section.

Prasad S. Nanobiosensors: the future for diagnosis of disease? Nanobiosensors in Disease Diagnosis. 2014;3:1-10

Jo, Eun-Jung & Byun, Ju-Young & Mun, Hyoyoung & Kim, Min-Gon. (2017). Luminescence resonance energy transfer (LRET) aptasensor for ochratoxin A detection using upconversion nanoparticles. 1032404. 10.1117/12.2267206.

The Hong Kong Polytechnic University. "Novel nano biosensor developed for rapid detection of flu virus."

S. Hassanpour, B. Baradaran, M. Hejazi, M. Hasanzadeh, A. Mokhtarzadeh, M. de la Guardia, Recent trends in rapid detection of Influenza infections by Bio and nanobiosensor, Trends in Analytical Chemistry (2017), doi: 10.1016/j.trac.2017.11.012.