Paper modification strategies for bacterial sensing: Progress and prospects in pathogen detection

Pathogenic bacteria are a leading cause of infections and are transmitted to humans through the ingestion of contaminated water, food, and other biological samples. Rapid and reliable detection of bacterial pathogens is critical for effective disease management. Paper-based sensors have emerged as highly attractive tools for bacterial detection due to their low cost, portability, ease of fabrication, and disposability. These sensors are often being produced using standard office equipment, making them a cost-effective and scalable technology for point-of-care diagnostics. The inherent properties of paper like lightweight, easy to handle, and capable of supporting chemical modifications make it an excellent platform for developing robust, rapid, and affordable diagnostic devices. This review focuses on the use of paper-based sensors for the detection of pathogenic bacteria and bacterial infections, particularly those associated with infectious diseases. The main focus is on the surface modification of paper through hydrophobic and hydrophilic treatments to enhance detection efficiency. Additionally, the integration of nanoparticles, polymer coatings, and various fabrication and signal amplification strategies are discussed. The review also highlights the advantages and limitations of different paper types and provides a critical analysis of previously reported paper-based sensing systems. This comprehensive overview aims to guide future research and the development of more advanced paper-based diagnostic platforms.