Development of graphite carbon nitride based fluorescent immune sensor for detection of alpha fetoprotein

作者：Li, Yike; Dong, Lingyu; Wang, Xiangfeng; Liu, Yuan; Liu, Hailing; Xie, Mengxia^*

来源：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , 2018, 196: 103-109.

DOI：10.1016/j.saa.2018.02.012

• Graphite carbon nitride
• Alpha fetoprotein
• Immunomagnetic separation
• Fluorescent immunosensor

A novel fluorescent immunosensor for determination of alpha fetoprotein (AFP) in serum samples has been developed based on the nano graphite carbon nitride (g-C3N4) as fluorophore and immunomagnetic beads (MBs) as separation material. The bulk g-C3N4 was obtained by thermal polymerization of melamine, and then carboxylated and exfoliated to acquire the carboxylated nano g-C3N4 (c-n-g-C3N4), which has been characterized and the results showed that it had excellent fluorescent properties. The antibodies of AFP (Ab(1), Ab(2)) were conjugated to the MBs and the c-n-g-C3N4, respectively. In assay of AFP detection, the magnetic part of the immunosensor, MBs-Ab(1), would form the sandwich type complex with the signal part of the sensor, c-n-g-C3N4-Ab(2). The developed immunosensor could simplify the process of separation due to the MBs. The results illustrated that proposed approach held a good linearity between the fluorescence intensity of the sensor and the AFP concentration ranging from 5-600 ng/mL with the limit of detection as low as 0.43 ng/mL, and its spiking recoveries ranged from 98.2% to 105.9% with RSD from 2.1% to 3.5%. The fabricated fluorescent immunosensor possesses the merits of good sensitivity, excellent selectivity, high biocompatibility and low cost, and the results provide a novel clue to develop immunosensor for determination of the biomarkers in complex matrices.

• 出版日期2018-5-5
• 单位北京师范大学