MicroRNAs (miRNAs) are endogenous molecules with regulatory functions. The purification and enrichment of miRNA are essential for its precise and sensitive detection. miRNA isolated using commercial kits contains abundant interfering RNAs, and the concentration of miRNA may not be adequate for detection. Herein, we prepared a reduced graphene oxide (rGO)-based magnetic solid-phase extraction material for the enrichment and ultrasensitive detection of miRNA from intricate nucleic acid solutions. In situ reverse transcription (RT) was developed as the most efficient approach to desorb miRNA from rGO among the methods that are compatible for the subsequent amplification reported thus far. Additionally, rolling circle amplification and qPCR were used to detect let-7a with a decrease of the limit of detection by 24.7- and 31.3-fold, respectively. This material was also successfully used to extract and detect miRNA from total RNA isolated from human plasma. Our results show that the material prepared in this study has the potential for cancer biopsy in clinics and the discovery of new miRNAs in scientific research.

中文翻译：

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减少的基于氧化石墨烯的固相萃取，用于microRNA的富集和检测

微小RNA（miRNA）是具有调节功能的内源性分子。miRNA的纯化和富集对其精确和灵敏的检测至关重要。使用市售试剂盒分离的miRNA包含大量干扰RNA，miRNA的浓度可能不足以进行检测。在这里，我们准备了一种基于还原性氧化石墨烯（rGO）的磁性固相提取材料，用于从复杂的核酸溶液中富集和超灵敏地检测miRNA。原位逆转录（RT）被开发为从rGO解吸miRNA的最有效方法，与迄今为止报道的后续扩增方法兼容。另外，使用滚环扩增和qPCR检测let-7a，检测限分别降低24.7和31.3倍。该材料还成功地用于从人血浆分离的总RNA中提取和检测miRNA。我们的结果表明，本研究中制备的材料具有用于临床癌症活检和科学研究中发现新miRNA的潜力。