Stable DNA Aptamer–Metal–Organic Framework as Horseradish Peroxidase Mimic for Ultra-Sensitive Detection of Carcinoembryonic Antigen in Serum

Abstract

Carcinoembryonic antigen (CEA) is an important broad-spectrum tumor marker. For CEA detection, a novel type of metal–organic framework (MOF) was prepared by grafting CEA aptamer-incorporated DNA tetrahedral (TDN) nanostructures into PCN-222 (Fe)-based MOF (referred as CEAapt-TDN-MOF colloid nanorods). The synthesized CEAapt-TDN-MOF is a very stable detection system due to the vertex phosphorylated TDN structure at the interface, possessing a one-year shelf-life. Moreover, it exhibits a significant horseradish peroxidase mimicking activity due to the iron porphyrin ring, which leads to a colorimetric reaction upon binding toward antibody-captured CEA. Using this method, we successfully achieved the highly specific and ultra-sensitive detection of CEA with a limit of detection as low as 3.3 pg/mL. In addition, this method can detect and analyze the target proteins in clinical serum samples, effectively identify the difference between normal individuals and patients with colon cancer, and provide a new method for the clinical diagnosis of tumors, demonstrating a great application potential.

A molecularly imprinted antibiotic receptor on magnetic nanotubes for the detection and removal of environmental oxytetracycline

“…[14][15][16] Halloysite nanotubes (HNTs), a clay aluminosilicate mineral, exhibiting several elegant properties such as strong interactions, good dispersibility, and large surface area, have gained enormous interest in recent years. 17 In contrast with other nanosized materials, like carbon nanoparticles, 18,19 metal-organic frameworks, 14,20 and quantum dots, 15,16,21,22 HNTs are available in thousands of tons at a low price, making them a promising candidate for nanoarchitecture composites. A classic example is the magnetic HNTs (MHNTs), onto which Fe 3 O 4 can be adsorbed due to the abundant hydroxyl groups on the surface of the HNTs.…”

Recent advancements in the specific determination of carcinoembryonic antigens using MOF-based immunosensors

“…Remarkably, the superior advantages of MOFs such as low cost, stability, mass production, and ease of transport along with visual detection ability can make this immunosensor suitable for point-of-care testing in resource-poor or remote areas. In another work, Sha and coworkers 59 developed a stable MOF-based colorimetric immunosensor as a horseradish peroxidase mimic for the determination of CEAs in serum samples. To achieve an interface assembly process and good molecular recognition, zirconium (Zr) metal ions were used as ligands.…”

MOF-Based Biosensors for the Detection of Carcinoembryonic Antigen: A Concise Review

“…The change in absorbance can be measured as a function of the different concentrations of clinical biomarkers [ 64 ]. For CEA colorimetric detection, a group of researchers synthetized a novel biosensor based on a PCN-222 MOF, which was prepared by grafting CEA aptamer-incorporated DNA tetrahedral (TDN) nanostructures [ 65 ]. The synthesized CEA aptamer-TDN-MOF showed a high detection stability due to the iron porphyrin ring in the PCN-222 MOF, which possesses significant horseradish peroxidase-mimicking activity, which leads to a colorimetric reaction upon binding toward antibody-captured CEA.…”