Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, Nathan, 4111, Queensland, Australia.
Chemphyschem. 2021 Jan 7;22(1):99-105. doi: 10.1002/cphc.202000760. Epub 2020 Nov 26.
Liquid marbles are a promising microreactor platform that recently attracts significant research interest owing to their ability to accommodate a wide range of micro reactions. However, the use of destructive and ex-situ methods to monitor reactions impairs the potential of liquid-marble-based microreactors. This paper proposes a non-destructive, in situ, and cost-effective digital-imaging-based colourimetric monitoring method for transparent liquid marbles, using the enzymatic hydrolysis of starch as an illustrative example. The colourimetric reaction between starch and iodine produces a complex that exhibits a dark blue colour. We found that the absorbance of red channel of digital images showed a linear relationship with starch concentration with high sensitivity and repeatability. This digital-imaging-based colourimetric method was used to study the hydrolysis of starch by α-amylase. The results show high accuracy and applicability of first-order kinetics for this reaction. The demonstration of digital-imaging-based colourimetry indicates the potential of liquid marble-based microreactors.
液滴包埋球是一种很有前途的微反应器平台，由于其能够容纳广泛的微反应，最近引起了人们的极大研究兴趣。然而，使用破坏性和非原位方法来监测反应会损害基于液滴包埋球的微反应器的潜力。本文提出了一种非破坏性、原位和具有成本效益的基于数字成像的比色监测方法，用于透明液滴包埋球，以淀粉的酶解为例。淀粉和碘之间的比色反应生成一种呈现深蓝色的复合物。我们发现，数字图像红色通道的吸光度与淀粉浓度呈线性关系，具有高灵敏度和可重复性。该基于数字成像的比色法用于研究α-淀粉酶对淀粉的水解。结果表明，该反应的一级动力学具有很高的准确性和适用性。基于数字成像的比色法的演示表明了基于液滴包埋球的微反应器的潜力。
