title: GSM5111144: L97940; Homo sapiens; ncRNA-Seq
library_construction_protocol: miRNeasy Serum/Plasma Advanced Kit 1)Filter small RNA: separate18-30nt RNA segment by PAGEgel.  2) 3' adaptor ligation: link 5-adenylated, 3-blocked single-stranded DNA adapter to 3'  end of selectedsmall RNAs from step1.  3) Reverse primer annealing: the RT primer is added to the solution from step 2, and is  cross-linked to the 3'adapter of RNAs and excessive free 3'adapter.  4) 5' adaptor ligation: the 5' adaptor is linked to the 5' end of the product from step 3. The  connection (5' adaptor) will be attached to the 5' end only, but it is not c onnected to  the 3'adaptor or RT primer hybrid chain.This greatly reduces self-ligation.  5) Strand cDNA synthesis: reverse extend the RT primer in step 3 to synthetize strand  cDNA.  6) PCR amplification: use high-ping polymerase to amplify cDNA, enrich cDNA with  both3'and5'adaptor. 7) Library fragment selection: separate the PCR product of 100~120bp by PAGE gel to  eliminate primer-dimer and other by products.  8)Library quantitative and pooling cyclization.