DNA sensor paper-based analytical devices for pathogen detection

Food poisoning caused by contaminated pathogen in the food and water is a global health issue. According to the World Health Organization (WHO), there are over 300 million cases of the food poisoning related to bacteria. Early monitoring pathogens in the food is therefore significant to medical diagnosis to reduce the modality. Traditional assays, including plate culture and polymerase chain reaction (PCR) have been extensively utilized in clinical laboratories since they provide remarkable selectivity and sensitivity. These methods are time-consuming, expensive, and require trained users. To overcome these challenges, in this work, we present a straightforward paper-based analytical device (PAD) for pathogen quantification using a laser printing. The detection method is based on the change in the fluorescent intensity on the PAD due to the binding between the target pathogen and a captured DNA probe and reported fluorescein isothiocyanate (FITC) labelled DNA probe. With this measurement, the target pathogen levels can be quantified. Consequently, the developed fluorescent PAD offers various advantages of cost-effectiveness, simplicity, and user-friendliness. The concept also holds significant potential as an effective alternative tool for pathogen analysis and expanded to advanced applications in monitoring other analytes.