Portable paper device rapidly detects scopolamine in beverages

Isabel Poves, researcher at the University of the Basque Country-EHU, has developed a microfluidic paper-based device that provides a rapid, reliable and easy way to detect scopolamine and related compounds. This low cost, portable system gives a visual readout in around 10 minutes and opens the way for conducting preliminary analyses on site, without the need for laboratory equipment. The platform is a significant advancement towards the practical detection of drug-facilitated assault agents.

Assault facilitated by drugs such as scopolamine (popularly known as Devil’s Breath) is a serious public health and forensic concern. This drug is especially hazardous due to its strong amnesic, sedative and hallucinogenic effects, combined with its lack of colour, odour and taste, that prevents it from being detected when ingested. Despite its toxicological importance, there are still few methods available for the rapid on-site detection of scopolamine. The detection of these types of drugs relies on the use of instrumental analytical techniques, and while these provide high sensitivity and specificity, they require laboratory conditions and extensive sample preparation, making them impractical for rapid, on-site analysis.

To address the lack of portable, low-cost analytical tools for detecting scopolamine in a variety of matrices without the need for a laboratory, the Microfluidics Cluster EHU research group led by Ikerbasque Research Professor Lourdes Basabe-Desmonts, has developed a self-powered, microfluidic paper-based device for the rapid detection of scopolamine in pharmaceuticals, plant extracts and beverages. It is a discreet, portable and easy to use tool.

It consists of a self-powered microfluidic device with a paper support on which a reaction occurs, which results in a colour change according to whether the result is positive or negative. “The device is immersed in the sample for a few seconds, and after around 10 minutes the result can be seen with the naked eye, without the need for any other type of detector”, explains Isabel Poves, lead author of the study. She believes that “this device will help prevent drug-facilitated assault, because more important than detecting it after the fact, is trying to prevent it from happening in the first place. We need to be able to quickly detect whether a drink contains an adulterating substance.”

Detection of different types of drugs using a single device

“Microfluidic technology opens the door to a type of analysis that was impossible before”, explains Poves, predoctoral researcher with the group. In the past, to find out whether something had been added to your drink, you would have had to take a sample to a specialised laboratory for analysis. This technology enables a preliminary analysis to be conducted on site. Microfluidic technology consists of miniaturising or simplifying processes that are carried out on a larger scale in a laboratory, so that the sample does not need to be handled in any way.

The paper published in the scientific journal Talanta helps bring us closer to the objective of developing a microfluidic platform capable of detecting multiple drugs through a single colorimetric reaction. In fact, the study forms part of a larger project led by the Microfluidics Cluster UPV/EHU group, which seeks to detect as many drugs as possible using a single device. This would involve integrating various known chemical reactions used for drug detection into microfluidic technology and improving the designs, thus taking advantage of the ability to achieve rapid results. “We are trying to adapt the colorimetric chemical reactions to microfluidic technology in order to simplify this type of detection, to lower costs, automate the process and, in particular, to be able to see with the naked eye a colour change indicating that a beverage has been adulterated”, explains Lourdes Basabe, lead researcher of the group.

In this respect, the University of the Basque Country-EHU research group has recently developed another device aimed at detecting benzodiazepines (e.g. Diazepam, medically used for treating anxiety, insomnia, etc.) in beverages, with the same characteristics as the device in this study.

The researchers emphasize that there is still a lot of laboratory work to be done: “This is a laboratory level prototype that can be refined according to user needs. We need to continue to improve these devices to optimise the detection ranges, colour changes, etc.” In the future, this analysis could potentially be conducted using existing smartphone applications that accurately analyse the colour displayed on the device.