Table 1.
Binding efficiencies of single-stranded DNA (ssDNA) oligonucleotides to SPRI beads at varying isopropanol concentrations
| Oligo size (nt) | Isopropanol concentration (%) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 30 | 32 | 35 | 38 | 41 | 44 | 48 | 51 | 54.5 | |
| 66 | 21 | 56 | 74 | 87 | 97 | 100 | ND | ND | ND |
| 58 | ND | 4 | 8 | 42 | 80 | 89 | ND | ND | ND |
| 44 | ND | 2 | 3 | 13 | 40 | 59 | 75 | ND | ND |
| 37 | ND | ND | 1.5 | 4 | 11 | 19 | 45 | 80 | ND |
| 30 | ND | ND | ND | ND | 4 | 5 | 20 | 40 | 61 |
| 21 | ND | ND | ND | ND | ND | 2 | 4 | 7 | 15 |
| 19 | ND | ND | ND | ND | ND | 1 | 3 | 3 | 5 |
100 ng ssDNA oligonucleotides were brought to a total volume of 50 μl with H2O, and appropriate amounts of SPRI beads (in 20% PEG, 2.5 M NaCl) and 100% isopropanol were added to obtain the desired concentrations (for added quantities see Methods). Oligonucleotides bound to beads were next separated, washed, and eluted. Oligonucleotide quantities in the eluate and in the input solution were determined by fluorometer. Binding efficiency was calculated as the percentage of eluted ssDNA from the input quantity. Each data point represents an average of at least three separate experiments.
ND not determined