Bioinspired Carbohydrate-Decorated Long-Period Fiber Grating for Label-Free Bacteria Detection

Pathogenic bacteria cause thousands of human infections every year. Their effective detection can prevent diseases, decrease the cost of patient hospitalizations, and thus enhance the standard of people's life. Here, we present a bioinspired sensor for bacteria detection in water, which is based on long-period fiber grating (LPFG) and α-mannoside receptor. Embedding of p-aminophenyl-α-D-mannopyranoside, sensitive to E. coli strain, into the biosensor, allows mimicking natural bacteria adhesion to the host cell. The receptor has been covalently immobilized by a thiourea bond to the LPFG platform to ensure stable and reproducible work. The lowest detectable concentration of bacteria was equal to 103 colony forming unit ml
^-1
.