Phenylboronic acids have emerged as synthetic receptors that can reversibly bind to cis-diols of glucose molecules. The incorporation of phenylboronic acids in hydrogels offers exclusive attributes; for example, the binding process with glucose induces Donnan osmotic pressure resulting in volumetric changes in the matrix. However, their practical applications are hindered because of complex readout approaches and their time-consuming fabrication processes. Here, we demonstrate a microimprinting method to fabricate densely packed concavities in phenylboronic acid functionalized hydrogel films. A microengineered optical diffuser structure was imprinted on a phenylboronic acid based cis-diol recognizing motif prepositioned in a hydrogel film. The diffuser structure engineered on the hydrogel was based on laser-inscribed arrays of imperfect microlenses that focused the incoming light at different focal lengths and direction resulting in a diffused profile of light in transmission and reflection readout modes. The signature of the dimensional modulation was detected in terms of changing focal lengths of the microlenses due to the volumetric expansion of the hydrogel that altered the diffusion spectra and transmitted beam profile. The transmitted optical light spread and intensity through the sensor was measured to determine variation in glucose concentrations at physiological conditions. The sensor was integrated in a contact lens and placed over an artificial eye. Artificial stimulation of variation in glucose concentration allowed quantitative measurements using a smartphone's photodiode. A smartphone app was utilized to convert the received light intensity to quantitative glucose concentration values. The developed sensing platform offers low cost, rapid fabrication, and easy detection scheme as compared to other optical sensing counterparts. The presented detection scheme may have applications in wearable real-time biomarker monitoring devices at point-of-care settings.

中文翻译：

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苯硼酸官能化的基于水凝胶的光学扩散器的葡萄糖感测。

苯硼酸已经成为合成的受体，可以可逆地结合到葡萄糖分子的顺式二醇上。苯硼酸在水凝胶中的结合具有独特的特性。例如，与葡萄糖的结合过程会诱导Donnan渗透压，从而导致基质中的体积变化。然而，由于复杂的读出方法及其耗时的制造过程，它们的实际应用受到了阻碍。在这里，我们展示了一种微压印方法，可在苯硼酸官能化的水凝胶膜中制造密集堆积的凹面。将微工程化的光学漫射体结构印在预先置于水凝胶膜中的苯基硼酸基顺式二醇识别基序上。在水凝胶上设计的扩散器结构基于不完整的微透镜的激光刻划阵列，该阵列将入射光聚焦在不同的焦距和方向上，从而在透射和反射读出模式下产生光的散射轮廓。由于水凝胶的体积膨胀改变了扩散光谱和透射光束轮廓，因此通过改变微透镜的焦距来检测尺寸调制的特征。测量通过传感器的透射光的传播和强度，以确定在生理条件下葡萄糖浓度的变化。该传感器集成在隐形眼镜中，并置于假眼上。通过人工刺激葡萄糖浓度的变化，可以使用智能手机进行定量测量 的光电二极管。利用智能手机应用程序将接收到的光强度转换为定量的葡萄糖浓度值。与其他光学传感同类产品相比，已开发的传感平台提供了低成本，快速制造和简便的检测方案。提出的检测方案可能在即时医疗点设置下可穿戴实时生物标记监测设备中得到应用。