The NucleoSpin miRNA Plasma procedure is a simple and fast method to isolate small RNA >15 nt, such as micro RNA (miRNA), from serum or plasma. The DNA can be isolated as well or digested on-column to eliminate interference of miRNA-encoding DNA with downstream applications.

Higher yield, higher quality, quicker procedure

The performance of NucleoSpin miRNA Plasma was compared with competitor kits (below). MN (NucleoSpin miRNA Plasma): miRNA was isolated from 300 μl of human blood plasma. Competitor Q: sample volumes of 1,000 μl and 200 μl were used with kits for circulating nucleic acids (Q-CNA) and miRNA (Q-miRNA), respectively, according to Q´s supplementary protocols. Competitor A: 300 μl of plasma was processed according to the tissue protocol (6 volumes of lysis buffer) of a miRNA kit (A-miRNA).

Higher miRNA yields

Purified miRNA (2 μl of each eluate) was used as template in quantitative realtime RT-PCR targeting miR-16 miRNA (Applied Biosystems, TaqMan MicroRNA RT Kit, hsa-miR-16 MicroRNA Assay). The results below show that CT values are lowest for NucleoSpin miRNA Plasma, indicating highest miRNA yields. As a result, NucleoSpin miRNA Plasma shows superior performance with or without optional DNase digestion.

Higher miRNA quality

Residual genomic DNA was estimated by qPCR of a 102-bp fragment of the elongation factor 1 gene using the 2x DyNAmo Capillary Master Mix (Finnzymes). There was no genomic DNA background detectable when performing the optional DNase digestion of the NucleoSpin miRNA Plasma kit. The results show that CT values are very high for NucleoSpin miRNA Plasma, indicating very low gDNA background.

Quicker procedure

By performing 10 preparations each, the quickest results were obtained by NucleoSpin miRNA Plasma both with and without rDNase digestion.

Consistent scaleup of sample volume

The standard sample volume of 300 μl can be scaled up to 900 μl by multiple loading. Purified miRNA was used as template in quantitative real-time RT-PCR for miR-16 miRNA (Applied Biosystems, TaqMan MicroRNA RT Kit, hsa-miR-16 MicroRNA Assay). The results show that CT values decrease with increasing sample volume, indicating a consistent rise in miRNA yields.