Continuous glucose monitor is very important for diabetes management, but its wide use is limited by invasive sampling, signal drift and frequent calibration. Micro needle sensor is a minimally invasive platform used for real-time monitoring of clinical parameters of interstitial fluid. In this paper, a painless flexible microneedle sensing patch is constructed with a strong mechanical strength microneedle base and a thin layer fluorescent hydrogel sensor to achieve on-site, accurate and continuous blood glucose monitoring.

Forster resonance energy transfer (FRET) - based hydrogel sensor is prepared by photopolymerization of acrylate acylated FRET pair and glucose specific phenylboronic acid. The optimized hydrogel sensor makes glucose quantification reversible, highly selective and stable against photobleaching signals. Poly (ethylene glycol diacrylate) - copolymer acrylamide hydrogel is used as the basis of microneedles to promote effective skin puncture and biofluid extraction. The sensitivity of the integrated microneedle sensor patch within the (pathological) physiological range is 0.029 mM − 1, with a low detection limit of 0.193 mM, and a response time of 7.7 min in human serum. Continuous monitoring of hypoglycemia, normal blood glucose, and hyperglycemia during simulated eating and resting activities for 6 hours in a pig skin model. This microneedle sensor with high transdermal analysis performance provides a powerful tool for continuous monitoring of diabetes in nursing point settings.

Source: Sensor Expert Network