A technique that in a matter of hours can make virus diagnosis reducing the cost of detectors by 80%. The Hong Kong Polytechnic University (PolyU) employs a nanoparticle biosensor that uses the upconversion LRET to detect viruses in a quick and cheap method, instead of using genetic analysis that is complicated, time consuming and expensive. RT-PCR (reverse transcription-polymerase chain reaction) is expensive and time-consuming while ELISA has a relatively low sensitivity.
Method: It involves the development of upconversion nanoparticles (UCNPs) conjugated with a probe oligo whose DNA base pairs are complementary with that of the gold nanoparticles (AuNPs) flu virus oligo. Given the complementary nature of the DNA base pairs of the UCNPs probe oligo and AuNPs flu virus oligo, they work like two matching pieces of magnet, which would be drawn together due to attraction force. This process is also called oligo hybridization. When the sample is then illuminated by near-infrared light (NIR), the upconversion nanoparticles emit a green radiance, while the AuNPs absorb green light. The concentration of virus is calculated by the decrease of green light.
This new technique is very simple, without requiring expensive apparatus or equipment to operate, and doesn’t demand any particularly sophisticated user skill-set, with comparable sensitivity to more expensive, traditional methods. In comparison to conventional downconversion luminescent technique, it causes low damage to genetic materials and does not induce background fluorescence.
CHIP & ADAPTED to developing countries. In spite of the low cost it is still HK$20.