Biomedical soft contact-lens sensor for in situ ocular biomonitoring of tear contents

• DOI: 10.1007/s10544-011-9530-x
• Publication Date: 2011-04-07T21:21:34Z
• Authors: MingXing Chu; Takayuki Shirai; Daishi Takahashi; Takahiro Arakawa; Hiroyuki Kudo; Kenji Sano; Shin-ichi Sawada; Kazuyoshi Yano; Yasuhiko Iwasaki; Kazunari Akiyoshi; Manabu Mochizuki; Kohji Mitsubayashi
• Keywords: Phosphorylcholine; Biomedical Technology; Biosensing Techniques; Contact Lenses, Hydrophilic; Eye; 03 medical and health sciences; Glucose; 0302 clinical medicine; Tears; Calibration; Animals; Methacrylates; Microtechnology; Dimethylpolysiloxanes; Rabbits; Vision, Ocular

A soft contact-lens biosensor (SCL-biosensor) for novel non-invasive biomonitoring of tear fluids was fabricated and tested. Wearing a biosensor on eye enabled the in situ monitoring of tear contents. The biosensor has an enzyme immobilized electrode on the surface of a polydimethyl siloxane (PDMS) contact lens. The SCL-biosensor was fabricated using microfabrication techniques for functional polymers (PDMS and 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer). In investigation of in vitro characterization, the SCL-biosensor showed excellent relationship between the output current and glucose concentration from 0.03 to 5.0 mmol·L(-1), with a correlation coefficient of 0.994. The calibration range covered the reported tear glucose concentrations (0.14 mmol·L(-1)). Based on the result, ocular biomonitoring with the SCL-biosensor was carried out. The SCL-biosensor well worked both in the static state and the dynamic state. The tear glucose level of rabbit was estimated to 0.12 mmol·L(-1) at first and then the tear turnover was successfully calculated to be 29.6 ± 8.42% min(-1). The result indicated that SCL-biosensor is useful for advanced biomonitoring on eye.