Detection of Bacteria in Water with β-Galactosidase-Coated Magnetic Nanoparticles

Pathogenic contamination and resistant bacterial infections remain critical concerns in both developed and developing countries. Rapid and sensitive detection of pathogens is still a key requirement for both environmental and clinical settings. This article introduces a simple, colorimetric, cost-effective, and high-throughput system based on a positively charged iron oxide/enzyme complex for the detection of both gram-positive and gram-negative bacteria in water between 103 and 108 cfu/mL. This study provides an effective strategy for the identification and purification of pathogen contamination in drinking water.