Korean team's carbon nanotube biosensor detects HIV-1 antibodies in high-ion serum-like conditions
KIT and Ajou University built a nanotube–gold junction sensor that registers antibody binding where ion concentration is high. The principle was verified on HIV-1 antibodies.
The National Institute of Toxicological Science (KIT) and Ajou University have developed a nanobiosensor platform that detects antibodies in environments with a high ion concentration, KIT announced on the 11th, according to biz.heraldcorp.com. The work was led by Lee Jae-hyuk, principal researcher at KIT's Environmental Safety Research Center. biz.heraldcorp.com
biz.heraldcorp.combiz.heraldcorp.comOpen source ↗ The results were published online on 4 September in the journal Biosensors and Bioelectronics.
Existing carbon nanotube biosensors are highly sensitive, but their detection performance drops in high-ion environments such as blood or serum. The team addressed this by focusing on the junction where a carbon nanotube meets a gold electrode.
Schottky junction as the signal source
Single-walled carbon nanotubes (SWNT), in which carbon atoms are arranged in a cylinder, have excellent electrical properties and are used as ultra-sensitive sensor material. The researchers detected antibodies through electrical changes in the Schottky junction that forms where the SWNT touches the gold electrode. With this approach, the signal from antibody binding could be read even in high-ion conditions.
According to Lee, the approach does not simply avoid the electrical signal screening that is a problem in real biological environments, but uses the electrical changes at the nanotube–gold junction to detect the signal. biz.heraldcorp.com
biz.heraldcorp.combiz.heraldcorp.comOpen source ↗
HIV-1 antibody test and next steps
To check performance, the team used antibodies against human immunodeficiency virus (HIV-1) as the detection target. The electrical signal produced when the antibodies bound to the sensor was observed in serum-like, high-ion conditions. The signal also varied with antibody concentration, which, per the report, points to possible development into quantitative analysis rather than only detecting presence.
HIV-1 antibodies were used to verify the operating principle. Changing the recognition material on the sensor surface would allow detection of other antibodies, proteins and biomarkers.
The researchers plan to combine the nanobiosensor with three-dimensional cell cultures and organoids derived from human stem cells. biz.heraldcorp.com
biz.heraldcorp.combiz.heraldcorp.comOpen source ↗ The aim is to measure in real time how cells and tissues respond to drugs or environmental hazardous substances and to analyze toxic responses in the human body more precisely. Lee said the team intends to develop the platform into a human-mimetic biosensing platform.
