金黄色葡萄球菌(SA)对人类和动物健康构成严重威胁,需要低成本和高性能的分析平台来进行即时诊断。纤维素纸基场效应晶体管(FET)与RNA裂解DNAzymes(RCD)可以满足低成本的要求,然而,其高亲水性和亲脂性阻碍了生化修饰,导致灵敏度低,机械稳定性差,污垢性能差。在这里,我们提出了一种可控的自清洁FET,以简化生化改性,提高机械稳定性和防污性能。然后,我们构建了基于RCD的DNA纳米树以显著提高SA检测的灵敏度.对于可控自清洁FET,1H,1H,2H,合成了基于2H-全氟癸基三甲氧基硅烷的聚合物纳米颗粒,用于装饰纤维素纸和全碳纳米薄膜线。O2等离子体用于调节以降低氟碳链密度,然后控制敏感区域的疏水-疏油性能。因为带负电荷的DNA会影响半导体FET的灵敏度,设计了三个低成本的Y形分支,并应用于基于相似的DNA折纸技术合成了基于RCD的DNA纳米树,进一步提高了灵敏度。DNA-纳米树干由RCD组成,顶篷是使用多个Y形分支自组装的。可控自清洁FET生物传感器用于SA检测,无需培养,线性范围为1~105CFU/mL,可检出低值1CFU/mL。
Staphylococcus aureus (SA) poses a serious risk to human and animal health, necessitating a low-cost and high-performance analytical platform for point-of-care diagnostics. Cellulose paper-based field-effect transistors (FETs) with RNA-cleaving DNAzymes (RCDs) can fulfill the low-cost requirements, however, its high hydrophilicity and lipophilicity hinder biochemical modification and result in low sensitivity, poor mechanical stability and poor fouling performance. Herein, we proposed a controllable self-cleaning FET to simplify biochemical modification and improve mechanical stability and antifouling performance. Then, we constructed an RCD-based DNA nanotree to significantly enhance the sensitivity for SA detection. For controllable self-cleaning FET, 1 H,1 H,2 H,2 H-perfluorodecyltrimethoxysilane based-polymeric nanoparticles were synthesized to decorate cellulose paper and whole carbon nanofilm wires. O2 plasma was applied to regulate to reduce fluorocarbon chain density, and then control the hydrophobic-oleophobic property in sensitive areas. Because negatively charged DNA affected the sensitivity of semiconducting FETs, three Y-shaped branches with low-cost were designed and applied to synthesize an RCD-based DNA-Nanotree based on similar DNA-origami technology, which further improved the sensitivity. The trunk of DNA-Nanotree was composed of RCD, and the canopy was self-assembled using multiple Y-shaped branches. The controllable self-cleaning FET biosensor was applied for SA detection without cultivation, which had a wide linear range from 1 to 105 CFU/mL and could detect a low value of 1 CFU/mL.