People with diabetes mellitus rely predominantly on finger pricking to measure blood levels of glucose, which can be onerous. A popular alternative is electrochemical microneedles used in continuous glucose monitors; however, these systems measure glucose levels in the interstitial fluid rather than in the blood directly, which potentially results in inaccurate measurements. A study in Nature Metabolism describes a new system for non-invasive measurement of blood levels of glucose using optoacoustic imaging.

The researchers tested the DIROS system in mice by measuring blood levels of glucose before and after a glucose tolerance test. Measurements were taken from the ear skin of the mice as well as the interstitial fluid, and validated with regular blood sampling. “Signals collected from within volumes rich in microvasculature related better to glucose concentrations than measurements from the interstitial fluid,” explain Ntziachristos, Pleitez and Uluç. Furthermore, Fourier-transform infrared spectroscopy measurements confirmed that there was a low chance of interference from other blood-based proteins and metabolites (such as lactate and albumin) when measured at physiological concentrations.

糖尿病患者主要依靠刺破手指来测量血糖水平，这可能是一项繁重的工作。一种流行的替代方案是用于连续血糖监测仪的电化学微针；然而，这些系统测量间质液中的葡萄糖水平，而不是直接测量血液中的葡萄糖水平，这可能导致测量不准确。《自然代谢》中的一项研究描述了一种使用光声成像无创测量血糖水平的新系统。

研究人员通过测量葡萄糖耐量测试前后的血糖水平来测试小鼠的 DIROS 系统。从小鼠的耳部皮肤以及间质液中进行测量，并通过定期采血进行验证。 Ntziachristos、Pleitez 和 Uluç 解释说：“与从间质液中测量的信号相比，从富含微脉管系统的体积内收集的信号与葡萄糖浓度的相关性更好。”此外，傅里叶变换红外光谱测量证实，在生理浓度下测量时，其他血液蛋白和代谢物（例如乳酸和白蛋白）干扰的可能性很小。