Test of an Improved DNA and RNA Purification Protocol—Importance of Proteinase K and Co-Purified Small RNAs

Optimized and reliable DNA/RNA extraction protocols are a vital tool in clinical practice the context of molecular testing. Here, we present our successful attempt to enhance quantity RNA isolated from specimens, which originally found challenging (breast testis). We compared several purification methods with special focus on two AllPrep system-based (QIAGEN). Our data suggest that addition proteinase K may markedly increase and, some cases, also DNA yield. The kit used, DNA/RNA/miRNA universal kit, provides amounts comparable phenol-chloroform method; however, part final yield consisted small RNAs, visible as thick band bioanalyzer gel-like image (5S peak). 5S peak, albeit cases dominating image, plays only role RT-qPCR analysis, Qubit or NanoDrop measurements can still be used estimate starting mRNA for downstream analyses. In conclusion, showed implementing protocol containing step digestion increases Universal Kit successfully simultaneous total RNA, irrespective tissue origin, does not inconveniences related extraction.