Reusable Bacteriophage Adhesin-Coated Long-Period Grating Sensor for Bacterial Lipopolysaccharide Recognition

In this study, we report an application of the reusable optical fiber long-period grating (LPG) biosensor working near the dispersion turning point of higher order cladding modes. The presented device is capable of bacterial lipopolysaccharide (LPS) recognition. We show that the LPG sensor biofunctionalized with bacteriophage adhesin can be regenerated and successfully reused for very specific LPS detection. Thus, we show three series of label-free binding effect for specific to the adhesin E. coli B LPS and nonspecific H. alvei 1189 LPS (as a reference test) on a single LPG-based sensor. The resonance wavelength shift induced by the specific tests is significantly higher than that induced by the reference test. The LPG-based sensing structure allows for monitoring of the binding phenomenon in real time and with good accuracy.