Table 2:
Summary of the total protein assay results for the three different extraction methods and alterations
| Extraction Methods 1 and 2 | Extraction Method 3 | ||||
|---|---|---|---|---|---|
| Methanol–chloroform protein precipitation | TCA–acetone protein precipitation | RIPA cell lysis and extraction buffer | |||
| Original: acetone wash | Alteration 1: butanol de-lipidation | Alteration 2: water wash | |||
| Total protein assay | Pierce BCA | Pierce BCA | Pierce BCA | Pierce BCA | Pierce 660 nm |
| Minimum protein yield | 14.4 µg/g | 3.8 µg/g | 7.3 µg/g | 7.7 µg/g | 3101.8 µg/g |
| Maximum protein yield | 361.6 µg/g | 918.0 µg/g | 158.8 µg/g | 89.3 µg/g | 5512.7 µg/g |
| Extraction CVs (SD/mean) × 100 duplicate protein extracts | 28.4% (2.3–78.7%) | 42.0% (6.7–90.0%) | 50.6% (12.5–151.0%) | 31.8% (2.1–68.8%) | 21.9% (2.8–39.8%) |
| Inter-assay CVs (SD/mean) × 100 different total protein plates | 86.5% (47.8–133.1%) | 42.5% (0.5–141.4%) | 31.6% (4.1–103.9%) | 23.4% (3.31–69.5%) | 15.8% (1.5–64.9%) |
| Intra-assay CVs (SD/mean) × 100 same total protein plate | 0.7% (0.1–1.3%) | 2.0% (1.2–3.3%) | 28.7% (4.7–100.0%) | 19.3% (2.5–105.6%) | 4.5% (3.6–5.5%) |
CV, coefficient of variation; SD, standard deviation.