Sensors help determine the amount of medicine deep in the water

A Brazilian multidisciplinary research group has recently developed a biological sensor that helps measure pesticide content in food, water and soil. Technology is still in the development phase but if it becomes a commercial product, technology can bring an affordable, mobile solution to monitor this toxic chemical.

The biosensor is the result of the research of graduate student Izabela Gutierrez de Arruda at the São Carlos Physics Institute (IFSC), São Paulo state under the help of Dr. Romildo Jerônimo Ramos from the university. the federation of Mato Grosso (UFMT), Dr. Nirton Vristi Silva Viera (IFSC) and professor Franciso Eduardo Gontijo Guimarães (IFSC). Mechanism of action of the sensor is based on enzyme inhibitory method to detect the presence of a chemical group of organic phosphorus called methamidophos .

The team used acteylcholinesterase enzyme (AChE) - a highly active enzyme found in the cholinergic neuromuscular junction and nerve synapses of many insects and animals such as eel, fish, mammals and including human brain. The AChE enzyme works with the acetylcholine (ACh) nerve impulse transmitter involved in cognitive functions such as thinking and memory. When exposed to the molecule methamidophos, the enzyme activity of AChe is inhibited, making it produce less protons than normal. The difference in the amount of protons will be displayed on a small device that incorporates an ultra-thin film with a function to magnify the signal, thereby indicating the content of pesticides.

Gutierrez said: "The device looks like a device used to measure blood sugar levels. Because of its small size, farmers can perform measurements and get results immediately. Currently, people We often use chromatographic measurements or spectrometry to check pesticide content but these techniques require expensive expertise and equipment, in addition to being unable to immediately take the measurement results ".

The idea of ​​developing biosensors measures the amount of pesticides that arise from health problems caused by methamidophos to humans, particularly in the state of Mato Grosso, the largest rice producer in Brazil and also home town. Gutierrez's. Although methamidophos have been banned in many countries including EU countries, they are still widely used in Mato Grosso, directly threatening groundwater with chemical contamination risks.

Poisoning methamidophos can cause memory loss, anxiety, psychosis and according to scientists, it may increase the risk of Alzheimer's disease.

The team said that although biosensors are still in the research phase, it can be modified to measure a wide range of other pesticides and carbamates. Gutierrez's project was launched in 2011 and a patent on biosensors was also submitted. The next step is to find a company that is interested in technology and is ready to make this biological sensor a commercial product. The team estimates the cost of producing sensors will be between 46 and 92 USD.