Paper-Based Assays for Infectious Diseases, Health Screening, Genotyping, Environmental and Water Monitoring, and Cell-Based Assays

Jun Hui Soh, Jerry Toh, Kian Ping Chan, Daniel Lee, Siswand Mohd Ali, Xiaojun Chen and Jackie Y. Ying

To be effective in containing and fighting pandemics, it is important for healthcare providers and administrators to detect infectious diseases on-site rapidly and with great accuracy. To this end, we are developing a range of novel and practical diagnostic platforms that can be easily translated into point-of-care rapid test kits. Our new paper-based platforms can be used as in vitro diagnostic (IVD) kits to detect vector-borne diseases (17% of all infectious diseases), sexually transmitted infections (> 1 million new infections daily worldwide), and acute myocardial infarction (30% global mortality rate), etc. Using a small volume of blood or non-invasive saliva and urine samples, our rapid test kits are designed to be fast, accurate and user-friendly for self-testing, so as to facilitate health monitoring. We are also incorporating new capture agents, such as aptamers, short peptides, and new antibodies to improve our assay's performance. In addition to infectious disease diagnosis, our platform technology is versatile, and can also be used for health screening, genotyping, environmental and water monitoring, as well as cell-based assays.

Food Safety Test Kits

Siswand Mohd Ali, Jerry Toh, Jun Hui Soh and Jackie Y. Ying

Food-borne diseases have become a major global public health concern. Caused by bacteria, viruses, parasites, chemicals or toxins, they can be transmitted rapidly along the food chain and across borders to cause pandemics. Every year, almost 1 in 10 people around the world fall ill from food-borne diseases, and 420,000 of them die from it. Half of all food-borne illnesses are diarrheic diseases that are caused by eating contaminated food (WHO,2015). Bacteria like listeria, E. coli and Salmonella, and viruses like norovirus are among the most common causes of these diseases. Another area of public health concern is food fraud. Food scandals like the tainted milk powders found in China are a safety concern for consumers and also damaged their trust in the food industry. Therefore, consumers, companies and regulatory agencies are finding it increasingly important to be able to detect viruses in food and discern food ingredients accurately. Conventional methods of detecting pathogens in food rely on lab-intensive and time-consuming culture methods, which take days to deliver the final result. Our lab is addressing this important healthcare challenge by developing reliable and rapid food testing platforms.

Using our paper-based technology, we are developing test kits that can detect major bacterial and viral pathogens in food samples sensitively and rapidly. Our paper-based assays can also be employed for meat speciation.

In addition, we are developing an automated sample preparation system that would enable rapid sample processing, as well as bacteria enrichment and isolation. This will be integrated with our unique lab-on-a-chip system, called the OmegaPlex Chip, which is designed to provide multiplexing or simultaneous detection of bacteria and/or viruses from a single sample. The microfluidic system will enable us to achieve rapid detection of a whole range of common food-borne pathogens, as well as drug-resistant bacteria, including Carbapenem-resistant enterobacteriaceae (CRE) and Vancomycin-resistant enterococci (VRE).

Smart Diaper Monitoring System

Jun Hui Soh, Xiaojun Chen and Jackie Y. Ying

By 2030, more than 20% of the world's population will be at least 65 years old, and 35% of those over 60 years old are expected have problems with incontinence. Currently, incontinence management in nursing homes and hospitals relies on the use of diapers and their routine check. However, ensuring the timely change of soiled diapers is a big challenge. Consequently, patients would lie in soiled diapers for prolonged periods, increasing the risks of contracting diaper dermatitis, skin ulceration and infection.

We are developing a smart diaper monitoring system to address this problem. Multiple compact sensors for detecting urine and feces, and analyzing concentrations of sodium ions, urea and creatinine, are embedded in the diapers worn by the elderly and immobile patients. When the wearer passes urine or feces, the sensors are triggered to generate electrical signals, which are transmitted wirelessly to a central monitoring system to alert the caregiver via SMS to change the patient's soiled diaper. The analysis of urinary components is also reported for monitoring of kidney function. Our event-driven incontinence management approach can help to raise productivity in the labor-intensive healthcare industry and significantly improve the quality of patientcare.