MIT researchers develop a simple new chip that simplifies sample preparation and reduces sample volume for micro-RNA analysis
近年来，微RNA（micrornas）已成为一系列疾病的潜在生物标志物。These short (~22 nucleotide) sequences of non-coding RNA function by silencing messenger RNA and thus,provide a form of post-transcriptional regulation in the cell.Consequently,their regulation can have a significant impact on cell function.While they are implicated in many diseases,their role in cancer is of particular interest.众所周知，与健康组织相比，肿瘤中的多个小RNA表达失调，可作为肿瘤诊断的生物标志物。Testing for multiple miRNAs provides a better diagnosis,因此，能够将它们作为一个面板进行测试是很重要的。There are many techniques available to test for miRNAs such as gene chips,quantitative RT-PCR,和RNA SEQ，but these technologies all have their own shortcomings.他们的共同点是需要制备样品，主要从被测组织或细胞中提取RNA。In their recent HOT article,Tentori and researchers from theDoyle Group at MIT describe a chip that could overcome this problem and perform multiplexed testing of miRNA all within a minimum volume of just a few nanoliters.
The new chip comprises two glass slides which can be sandwiched together.The bottom slide has an array of 300 µm diameter wells which contain the miRNA sensors and serve to isolate samples into a small reaction volume.The top slide is then used to deliver lysis reagents to the sample.作者尝试了各种各样的顶板设计，but ultimately settled on an array of 30 µm diameter wells.这有两个优点；1）试剂精确计量；2）上下板夹心牢固，无需精确搬运或对准。最后一点对奥古斯托·滕托里来说非常重要，a postdoc in the Doyle Group and the lead author of the paper.Tentori wants "to make devices that are simple and robust,so translation is easier." The miRNA sensors are polyethylene glycol diacrylate (PEGDA) hydrogels that contain complementary DNA probes.The posts are photopolymerized in the wells and various sizes,shapes,并且可以制作柱子的图案。Further,a single well can contain a variety of posts,each functionalized with a different DNA probe targeting a different miRNA.这样，multiplexed assays can be performed with spatial separation.芯片的检测方式比以前的检测方式更灵敏，可以检测20个细胞中的小RNA。
Tentori is really excited about the prospects of this new chip.His co-authors include pathologists who have been guiding the project to make sure it is clinically useful,and he really wants to see this technology get into the hands of pathologists and diagnostic technicians.
Read the full article by Tentori et al.这里Quantitative and multiplex microRNA assays from unprocessed cells in isolated nanoliter well arrays" that features inLab on a Chip'S热门文章集.
关于网络作家
Darius Rackus (right) is a postdoctoral researcher in theDittrich生物分析组at ETH Zürich.His research interests are in developing integrated microfluidic tools for healthcare and bioanalysis
