Research Highlight

Probe to sense lactose in milk

doi:10.1038/nindia.2009.353 Published online 21 December 2009

Researchers have designed a nano-sensor that can detect the level of lactose, a sugar found in milk and other dairy products1.

This will be helpful in quality assessment of lactose hydrolysed products available in the market and aid people with lactose intolerance.

The researchers isolated beta-galactosidase (BGAL) from dry seeds of pea (Pisum sativum) and conjugated it with gold nanoparticles giving rise to lactose nano-sensor.

The gold nanoparticles with BGAL were found to be stable for 6 months under dried conditions. The sensor can be used five times with no loss in its activity and a loss of 50 per cent after 10 washes.

The lactose nano-probe is useful in estimating lactose in food samples with concentration less than 2 per cent.

"The sensor is a simple device and requires no expertise to handle," says lead researcher Arvind M. Kayastha from the School of Biotechnology, Faculty of Science, Banaras Hindu University, Varanasi. It is also cost-effective and user friendly, he adds.


  1. Dwevedi, A. et al. Lactose nano-probe optimized using response surface methodology. Biosens. Bioelectron. 25, 784-790 (2009) | Article | PubMed |