TABLE 1.
HPLC solubility determination resultsa
| Buffer | MgCl2 (mM) | DMSO | Solubility (μM) |
||
|---|---|---|---|---|---|
| RNPA2000 | NL20 | NL48 | |||
| KIN | 2% | ∼200 | ∼75 | ∼35 | |
| KIN | 5 | 2% | ∼25 | ||
| KIN | 10 | 2% | ∼30 | ||
| KIN | 10 | 10% | ∼60 | ∼210 | ∼13 |
| Tris | 2% | ∼200 | |||
| Tris | 5 | 2% | ∼25 | ||
| Tris | 5 | 10% | ∼40 | ||
| PBS | 2% | ∼200 | |||
RNPA2000 solubility was determined for different buffers with various amounts of MgCl2 and dimethyl sulfoxide (DMSO). For NL20 and NL48, solubility was only analyzed in kinetic (KIN) buffer at 2% DMSO and without Mg2+, and under the conditions used for enzyme kinetic assays. PBS, phosphate-buffered saline. For each measurement, at least six solutions with increasing concentration were subjected to HPLC. After plotting area under the curve (AUC) values for the corresponding compound concentrations, a linear correlation was obtained. The solubility was determined as the highest concentration at which there was still a linear correlation to be detected. Solubility limits are approximate, as the concentration variation was performed with a resolution of 5 or 10 μM steps. Evaluation for RNPA2000 is exemplarily shown in Fig. S4. Each measurement is based on at least 3 replicates.