Electrochemical microfluidic paper-based analytical devices for tumor marker detection

Cancer has become one of the crucial factors that endanger human beings. In order to effectively improve the treatment effect of cancer and improve the quality of life of patients, early screening of tumor markers is particularly critical. Compared with conventional detection methods, microfluidic paper-based analytical devices (μPADs) integrated with electrochemical detection methods have apparent advantages, such as being small, portable, and biodegradable, as well as fast analysis, high sensitivity, and low cost. As a result, electrochemical μPADs have become alternatives to conventional analytical instruments, and the related research has significantly increased. In this review, the fabrication process of μPADs was discussed first, mainly emphasizing the fabrication methods of paper-based hydrophobic barriers, including chemical and physical methods. Then, recent reports on μPADs using electrochemical detection methods for the detection of common tumor markers were discussed. Finally, the limitations of current electrochemical μPADs are also addressed.