Table 1. RNA purity (NanoDrop) and RNA integrity (2100 Bioanalyzer) for three different RNA extraction kits after storage of PBMCs in three different storage mediaa.
| PBMC storage medium | RNA extraction kit | NanoDrop A260/A280b | 2100 Bioanalyzer RINc | ||
|---|---|---|---|---|---|
| Run 1 (day 1) | Run 2 (day 83) | Run 1 (day 1) | Run 2 (day 83) | ||
| QIAzol | NucliSENS easyMAG | 2.0 ± 0.2 | 2.0 ± 0.1 | 1.0 ± 0.0 | 1.0 ± 0.0 |
| RNAlater | 2.0 ± 0.2 | 2.3 ± 0.2 | 1.0 ± 0.0 | 1.0 ± 0.0 | |
| easyMAG lysis buffer (EML) | 2.1 ± 0.3 | 2.1 ± 0.2 | 1.0 ± 0.0 | 1.0 ± 0.0 | |
| QIAzol | RNeasy Mini Kit | 1.9 ± 0.1 | 1.9 ± 0.1 | 9.4 ± 0.8 | 9.2 ± 0.3 |
| RNAlater | 1.6 ± 0.2 | 2.2 ± 0.3 | 8.2 ± 0.6 | 7.9 ± 0.6 | |
| RNeasy Mini Kit lysis buffer (RLT) | 1.9 ± 0.2 | 2.1 ± 0.1 | 8.7 ± 0.5 | 8.8 ± 0.5 | |
| QIAzol | RiboPure Kit—Blood | 2.0 ± 0.1 | 2.1 ± 0.2 | 1.0 ± 0.0 | 7.9 ± 0.5 |
| RNAlater | 2.1 ± 0.1 | 2.1 ± 0.0 | 8.1 ± 0.5 | 8.4 ± 0.6 | |
| RiboPure Kit–Blood lysis buffer (RPL) | 2.0 ± 0.0 | 2.0 ± 0.1 | 8.9 ± 0.6 | 8.6 ± 0.3 | |
a: Results are means and standard deviations of three independent extractions.
b: A value of ~2.0 is generally accepted as indicating that RNA is free of proteins.
c: The RIN value is reported on a scale of 1 to 10, whereby values above 7 are considered to represent high quality and non-degraded RNA.