Development of an on-column affinity smart polymer gel glucose sensor

An on-column affinity smart polymer gel glucose sensor was developed as a non-enzymatic glucose sensor. A copolymer of 3-acrylamidophenylboronic acid and acrylamide, the so called “smart polymer”, was synthesized in situ in a 5 cm long capillary tube with a detection window to provide the on-column detection. The optical density of this semitransparent affinity smart polymer gel, coated inside the tube, decreased with increasing glucose concentration and was detected using a UV–vis detector at 500 nm. The capillary tube was incorporated into a flow injection system. Under optimum conditions, a linear dynamic range of 0.5–16.0 mM with a limit of detection of 0.5 mM (S/N ≥ 3) was obtained. A single coated affinity smart polymer gel had good stability for up to 250 consecutive injections with relative standard deviation of less than 5%. The analysis time for each injection was 6 min. Ten glucose samples prepared in distilled water were analyzed by the developed method and the results compared well with those obtained from the conventional dinitrosalicylic acid (DNS) method (P > 0.05). Real urine samples with known glucose levels were analyzed and the developed sensor provided comparable results to those from the normal strip test technique. Acceptable percentage recoveries, ranging from 88 ± 2% to 103 ± 4% from the spiked urine sample, were obtained.

► Phenylboronic acid as a chemoselective ligand in an affinity smart polymer gel. ► Affinity smart polymer gel coated inside a short capillary tube. ► Optical density change of the gel depends on the concentration of glucose. ► On-column detection coupled with a flow injection system. ► Possibly automated glucose detection.