Lab on Paper: Adapting Quantitative Chemical Techniques for Use in Low Resource Areas

People need high quality fortified foods and medicines to protect their health. However, bad quality products are on the market. Regulatory agencies can remove bad products from the market but only after the quality is confirmed with expensive testing techniques. As a result, bad products persist in the marketplaces of low- and middle-income countries (LMICs). Analytical chemistry can solve this problem, but monetary and infrastructure problems prevent it from doing so. Labs are expensive to build, maintain, and employ with trained personnel. Labs are also reliant on a constant supply of electricity. The goal of my project was to design chemical analyses to work within the financial and infrastructure constraints of LMICs, thereby increasing testing capacity. I addressed this need for analysis outside the lab by adapting quantitative chemical tests to paper platforms, resulting in inexpensive technologies that require no technological infrastructure.

During the course of my thesis research, I engineered three test cards. Two test cards support universal salt iodization programs by quantifying the amount of iodate in fortified salt or by measuring urinary iodide levels. The cards can be used during surveillance studies to see if iodized salt is in the marketplace and whether the iodine is making its way into people’s diets. I made another card to quantify beta-lactam antibiotics in finished pharmaceutical pills, so the user can determine if the medicine contains the dosage stated on its label. I have taken these new technologies through validation studies to establish how well they work. All of them have about 90% accuracy or greater, and in some cases rival the performance of traditional analysis techniques.

These paper test cards could have real impact in LMICs. They are inexpensive, field- and user-friendly, not dependent on power or specialized instrumentation, and enable critical analyses to be performed in LMICs. Breaches in compliance systems could be detected immediately with paper analytical devices and texting the results to a database would isolate the geographic location. After confirming the bad results, public health agencies and law enforcement can be dispatched to remedy the situation, thereby protecting public health from low quality products.