Simultaneous Determination of Carcinoembryonic Antigen (CEA), Carbohydrate Antigen 19-9 (CA19-9), and Serum Protein p53 in Biological Samples with Protoporphyrin IX (PIX) Used for Recognition by Stochastic Microsensors

Abstract

Three of the most assessed biomarkers in the screening of biological samples for gastric cancer are carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and serum protein p53 (p53). Protoporphyrin IX immobilized in different nitrogen-doped graphene materials was used as the recognition molecule for the simultaneous determination of CEA, CA19-9, and p53 in various biological samples: whole blood, saliva, urine, and tissue samples. The proposed stochastic microsensors used as the recognition molecule protoporphyrin IX were reliable for the simultaneous determination of CEA, CA19-9, and p53 due to their high sensitivities and low limits of determination. The wide linear concentration ranges made possible the determination of the biomarkers in different stages of gastric cancer, from the earliest to the latest stages.