A disposable lab-on-a-chip platform for highly efficient RNA isolation

Despite recent advances in lab-on-a-chip (LOC) technology, RNA-based miniaturized diagnostic platforms have been falling behind due to a lack of on-chip RNA isolation techniques. However, RNA analysis plays an important role in gene expression determination and pathogen detection. To meet the increasing need for the analysis of RNA with point-of-care (POC) testing, a reliable LOC platform for RNA isolation needs to be developed. Here, we present a method of RNA isolation using a LOC platform that provides high-quality RNA from a variety of biological samples. By taking advantage of pH-dependent reversible dimethyl adipimidate (DMA) binding to RNA, we were able to perform RNA isolation on a disposable LOC platform within 30 min without the need for chaotropic salts or solvent. Using this LOC platform, gene expression analyses were successfully carried out with RNA isolated from different cell lines (HEK293, Caco-2, MCF-7, and T24) by subsequent real-time reverse transcription PCR. In addition, we validated the utility of this LOC platform with viral RNA isolated from Dengue viruses (DENV-1, −2, −4). We demonstrated a high recovery rate and rapid processing with minimal contamination. Therefore, this novel method could be an ideal RNA isolation technique in gene expression research and for the diagnosis of infectious diseases caused by RNA viruses in POC testing.