A UHPLC/MS/MS Assay Based on an Isotope-Labeled Peptide for Sensitive miR-21 Detection in HCC Serum

Background: MicroRNAs (miRNAs) have been identified as promising novel biomarkers for cancer diagnosis and prognosis, especially hepatocellular carcinoma (HCC). Nowadays, the expression level of miR-21 in serum samples is a diagnostic indicator HCC diagnosis. Thus, quantitative determination miRNA concentration significance clinical practice. It particularly important to establish an analytical detection method patient serum. Methods: The signal readout was based on mass response reporter peptide using isotope dilution spectrometry (MS) this work. To be more specific, biotinylated before being coupled with streptavidin (SA) agarose then hybridized newly synthesized DNA-peptide probe. release purification sample including trypsin digestion, solid-phase extraction, drying, carried out by UHPLC/MS/MS. corresponding quantified ratio chromatographic peak area redissolved polypeptide that isotope-labeled polypeptide. Additionally, within calibration range, performance (including precision, accuracy, linearity, recovery) evaluated. Results: determined relative stable internal standard peptide, yielding linear range 0.1∼30.0 nM (y = 0.0818x + 0.7554, R2 0.9586, P < 0.01). limit (LOD) 10 pM. For y5 , recoveries (n 3) were 91.36 ± 2.19%, 93.64 3.55%, 96.04 2.02% levels three RL, RM, RH, respectively. Conclusions: Overall, research provides approach miRNAs samples.