Carcinoembryonic antigen (CEA), as one of the common tumor markers, is a human glycoprotein involved in cell adhesion and is expressed during human fetal development. Since the birth of human, CEA expression is largely inhibited, with only low levels in the plasma of healthy adults. Generally, CEA will overexpressed in many cancers, including gastric, breast, ovarian, lung, and pancreatic cancers, especially colorectal cancer. As one of the important tumor markers, the detection of CEA has great significance in differential diagnosis, condition monitoring and therapeutic evaluation of diseases. Conventional CEA testing typically uses immunoassay methods. However, immunoassay methods require complex and expensive instruments and professional personnel to operate. Moreover, radioactive element may cause certain damage to the human body, which limits their wide application. In the past few years, biosensors, especially aptamer-based biosensors, have attracted extensive attention due to their high sensitivity, good selectivity, high accuracy, fast response and low cost. This review briefly classifies and describes the advance in optical and electrochemical aptamer biosensors for CEA detection, also explains and compares their advantages and disadvantages.

癌胚抗原（CEA）是一种常见的肿瘤标志物，是一种参与细胞黏附的人类糖蛋白，在人类胎儿发育过程中表达。自人类出生以来，CEA的表达受到很大的抑制，而健康成年人的血浆中CEA的表达水平却很低。通常，CEA在许多癌症中过表达，包括胃癌，乳腺癌，卵巢癌，肺癌和胰腺癌，尤其是结直肠癌。CEA的检测作为重要的肿瘤标志物之一，在鉴别诊断，病情监测和疾病治疗评价中具有重要意义。常规的CEA测试通常使用免疫分析方法。然而，免疫测定方法需要复杂且昂贵的仪器和专业人员。而且，放射性元素可能会对人体造成一定的损害，这限制了它们的广泛应用。在过去的几年中，生物传感器，尤其是基于适体的生物传感器，由于其高灵敏度，良好的选择性，高精度，快速响应和低成本而受到了广泛的关注。这篇综述简要地分类和描述了用于CEA检测的光学和电化学适体生物传感器的进展，并解释和比较了它们的优缺点。