Phenylboronic acid functionalized helical long period grating for glucose sensing

A glucose sensor based on a helical long-period grating (HLPG) coupling to a high-order cladding mode is demonstrated, which is composed of an optical fiber with the fiber surface modified by poly (4-vinylphenylboronic acid). The sensor has a linear response to glucose (0.18 ~ 3 mg/mL) with a sensitivity of 1.115 nm·(mg/mL) −1 at pH 7.4 and 3.259 nm·(mg/mL) −1 at pH 9, respectively.