Dye liquid crystals (DLCs) have been extensively investigated in the field of liquid crystal display, but their potential in biosensing has not been explored. To provide insights into the potential of DLCs as a means of biosensing material, a DLC-based biosensor was developed for protein detection and quantitation. Unlike dye-doped LCs, the DLC used in this study contains an azobenzene LC molecule chemically modified with two azo groups as chromophores, enabling the DLC to exhibit unique optical anisotropy and dichroic absorption at 470 nm, which were exploited in the quantitation of bovine serum albumin (BSA). The change in orientation of DLC molecules from the homeotropic to a disrupted state by BSA immobilized on the aligning-layer surface was evaluated in terms of the relative loss in transmittance, expressed by the standard parameter S%, due to the absorption as well as scattering of light. The DLC-based protein assay was capable of determining the BSA concentration, with which S% varied linearly between 1 μg/ml and 7.5 μg/ml. When the DLC molecules were reoriented from a BSA-disrupted state to the homeotropic alignment by an externally applied electric field, a linear correlation between S% and BSA concentration could be also derived from the voltage–transmittance plots. The unique electro-optical properties of the intrinsically dichroic DLC are promising toward the development of a simple and reliable sensing platform for the quantitative analysis of biomolecules.

在液晶显示器领域，已经对染料液晶（DLC）进行了广泛的研究，但尚未探索其在生物传感领域的潜力。为了深入了解DLC作为一种生物传感材料的潜力，开发了一种基于DLC的生物传感器用于蛋白质检测和定量。与染料掺杂的液相色谱不同，本研究中使用的DLC包含经过化学修饰的两个偶氮基团作为生色团的偶氮苯LC分子，使DLC在470 nm处表现出独特的光学各向异性和二向色性吸收，可用于牛血清的定量分析白蛋白（BSA）。通过以标准参数表示的相对透射率损失，评估了固定在取向层表面上的BSA导致DLC分子从垂直取向到破坏状态的取向变化。S％，归因于光的吸收和散射。基于DLC-蛋白测定是能够确定BSA浓度的，与小号1之间变化％线性 μ微克/毫升和7.5  μ微克/毫升。当通过外部施加的电场将DLC分子从BSA破坏状态重新定向为垂直排列时，S％和BSA浓度之间的线性相关性也可以从电压-透射率图得出。本征二向色性DLC的独特电​​光特性有望为开发简单可靠的传感平台进行生物分子定量分析提供希望。