High-performance olfactory receptor-derived peptide sensor for trimethylamine detection based on Steglich esterification reaction and native chemical ligation connection

• Published in: Biosensors & bioelectronics Vol. 195; p. 113673
• Main Authors: Wang, Zhi, Ma, Weichao, Wei, Junqing, Lan, Kuibo, Yan, Shanchun, Chen, Ruibing, Qin, Guoxuan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2022
• Subjects: Gas sensor; Native chemical ligation; Olfactory receptor-derived peptide; Single-walled carbon nanotube; Steglich esterification reaction; Trimethylamine; Native chemical ligation; Olfactory receptor-derived peptide; Gas sensor; Trimethylamine; Single-walled carbon nanotube; Steglich esterification reaction
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2021.113673

Trimethylamine (TMA) commonly exists in daily life and is harmful to human health, therefore the convenient and sensitive monitoring of TMA is highly desired. In this study, we developed a method to fabricate a high-performance TMA sensor by chemically conjugating olfactory receptor-derived peptides (ORPs) to single-walled carbon nanotubes (SWCNTs) on interdigital electrodes. First, the SWCNTs were modified with thioester by Steglich esterification reaction. Next, the ORPs with a cysteine residue at the N-terminus were connected to the thioester by native chemical ligation and modified to the surface of the SWCNTs. The chemical connection method enabled more effective loading of ORPs to the SWCNTs compared to the previously reported physical connection method. Using this approach, the ORPs-SWCNTs sensor for gaseous TMA was fabricated and enabled detection of TMA with a concentration as low as 0.01 parts per trillion, which was three orders of magnitude lower than the reported lowest detection limit up to date. Furthermore, we tested the performance of the ORP-sensor with vaporized TMA and TMA generated from various spoiled food, and the sensor exhibited excellent sensitivity, selectivity, and stability for TMA detection. The results demonstrated the effectiveness of the proposed chemical connection method for the fabrication of ORP-sensor and the great potential of using these sensors for applications in environmental safety, food quality evaluation, and healthcare. •The performance of ORP-sensor for TMA detection was significantly improved by chemical connection.•The proposed method provided high efficiency for connecting ORPs to the SWCNTs.•The fabricated ORPs-SWCNTs sensor enabled detection of gaseous TMA at concentration of 0.01 ppt.•The ORP-sensor showed excellent sensitivity, selectivity and stability for TMA generated from various spoiled food.