(321e) A New Surface Functionalized Biosensor for Long-Term In Vivo Glucose Monitoring

Diabetes mellitus is a metabolic disorder in which body is unable to control blood glucose level. This disease is a significant and expanding public health problem in USA. According to national diabetes statistics report, diabetes was the seventh leading cause of death in the United in 2015, and 30.3 million people (9.4% of the U.S population) have diabetes until 2017. Diabetes patients need regular and daily blood glucose monitoring to control their blood glucose level. The commonly commercial glucose meters are based on electrochemical sensors. They require fresh blood sample in each test, which can be painful and inconvenient for patients. Considering these drawbacks, developing new fully noninvasive or minimally invasive glucose monitoring devices became the primary need for frequently glucose detection. In this regard, optical techniques including fluorescent spectroscopy, surface enhanced Raman spectroscopy (SERS) are widely used in a number of studies. SERS is a powerful analytical method which can even detect signal molecule. However, this technique is hard to be used for glucose detection since the glucose molecule has low Raman active and affinity with metal surfaces. Herein, we developed a new glucose sensor that addresses the problems in SERS glucose detection. A probe molecule was chosen as an indirect reporter because the SERS signal of the reporter exhibits a glucose concentration dependent behavior on SERS substrate. After the validation of the concept using in vitro test, the as-prepared SERS glucose probe was injected in mice skin for in vivo continuous glucose monitoring. A commercial glucose meter, OneTouch®, was employed to track the blood glucose variation at the same time. Results of in vivo SERS detection shown extremely strong signal and similar trend compared with glucose meter, which proved that this new glucose sensor has great potential for minimally invasive glucose monitoring.