Specific gFET‐Based Aptasensors for Monitoring of Microbiome Quality: Quantification of the Enteric Health‐Relevant Bacterium Roseburia Intestinalis

Aptamer-modified rGO-FET biosensing demonstrated universality in detecting Roseburia intestinalis. The aptamers allowed specific quantification and discrimination of the desired target cells from other bacterial control cells with a lower detection limit of 10 cells mL⁻¹. Even in in the background of human stool samples, alterations of in the abundance of R. intestinalis in the range of 1% could easily be retraced.

Abstract

Roseburia intestinalis, enriched in the gut, is closely associated with obesity, intestinal inflammation, and other diseases. A novel detection method for R. intestinalis to replace the commonly used 16S rRNA sequencing technique is aim to developed, thus enabling real-time and low-cost monitoring of gut microbiota. The optimal solution is to utilize rGO-FET (reduced graphene oxide field-effect transistor) functionalized with aptamers. Due to the high sensitivity of graphene sensors to electronic changes in the system, it is anticipated to achieve detection sensitivity that traditional fluorescence detection techniques cannot attain. The previous work reported a nucleic acid aptamer library, Ri 7_2, capable of quantitatively tracking R. intestinalis in complex systems. However, due to the complexity of the aptamer library itself, large-scale industrial synthesis is challenging, significantly limiting its further commercial application potential. Therefore, in this study, through Next-Generation Sequencing analysis, four representative single aptamers from the aptamer library is strategically selected, named A-Rose 1, A-Rose 2, A-Rose 3, and A-Rose 4, and confirmed their excellent performance similar to the aptamer library Ri 7_2. Furthermore, aptamer-modified rGO-FET demonstrated universality in detecting R. intestinalis in a series of biochemical analyses, providing a novel and powerful diagnostic tool for the clinical diagnosis of R. intestinalis.