乳腺癌（BC）是全球女性最常见的癌症之一，也是女性癌症死亡的第二大原因。本研究的目的是介绍一种基于向列型液晶（LC）固有特征的非标记 LC 生物传感器，用于评估使用人表皮生长因子受体-2（HER-2）生物标志物的 BC。这种传感的机制通过与二甲基十八烷基[3-（三甲氧基硅基）丙基]氯化铵（DMOAP）进行表面修饰支持，鼓励长烷基链在界面处引起LC分子的同向取向。为了增强更多的HER-2抗体（Ab）与LC定向剂的结合效力，还使用了简单的紫外辐射辅助方法来增加DMOAP涂层玻片上的功能基团，从而提高结合亲和力和效率。设计的生物传感器利用HER-2蛋白质特异性结合HER-2 Ab和LC取向的破坏。这种取向改变导致光学外观从暗到双折射的转变，使HER-2检测成为可能。这种新型生物传感器在10-6-102 ng/mL的宽动态范围内对HER-2浓度呈线性光学响应，具有超低的检测限制（1 fg/mL）。作为概念验证，在BC患者中成功地研究了设计的LC生物传感器用于HER-2蛋白的定量。由于其灵敏度、选择性和非标记检测，此生物传感器可能扩大基于LC的生物传感器在检测多种癌症方面的应用。©2023作者（们）。

Breast cancer (BC) is one of the most commonly diagnosed cancers and the second leading cause of cancer mortality among women around the world. The purpose of this study is to present a non-labeled liquid crystal (LC) biosensor, based on the inherent feature of nematic LCs, for the evaluation of BC using the human epidermal growth factor receptor-2 (HER-2) biomarker. The mechanism of this sensing is supported by surface modification with dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride (DMOAP) encouraging the long alkyl chains that induce a homeotropic orientation of the LC molecules at the interface. To enhance the binding efficacy of more HER-2 antibody (Ab) on LC aligning agents, a simple ultraviolet radiation-assisted method was also used to increase functional groups on the DMOAP coated slides, thereby improving binding affinity and efficiency onto HER-2 Abs. The designed biosensor makes use of the specific binding of HER-2 protein to HER-2 Ab and disruption of the orientation of LCs. This orientation change leads to a transition of the optical appearance from dark to birefringent, enabling the detection of HER-2. This novel biosensor exhibits a linear optical response to HER-2 concentration in the wide dynamic range of 10-6-102 ng/mL, with an ultra-low detection limit of 1 fg/mL. As a proof of concept, the designed LC biosensor was successfully investigated for the quantification of HER-2 protein in patients suffering from BC. Owing to the sensitivity, selectivity, and label-free detection, this biosensor may amplify the application of LC-based biosensors for the detection of most types of cancers.© 2023. The Author(s).