Table 4.
Assessment of limit of detection and the concentration of pooled plasma sample.
| Vitamin | Normal Range (ng/mL) * | Limit of Detection (ng/mL) | Limit of Detection Fold Decrease from Lower Cutoff | Sample Concentration (ng/mL) |
|---|---|---|---|---|
| B2 (Riboflavin) | 1–19 | 0.2 | 5 | 19.9 |
| B3 (Nicotinamide) | 5–75 | 0.05 | 104 | 38.8 |
| B5 (Pantothenic acid) | 37–147 | 0.2 | 185 | 122.7 |
| B6 (Pyridoxine) | 5–50 | 0.05 | 100 | 18.7 |
| B7 (Biotin) | 0.2–3.0 | 0.5 | 0.4 | 7.4 |
The limit of detection was determined as the lowest detectable concentration from the standard curve. To obtain the fold decrease from the lower limit, we divided the lower cutoff from the reference range by the limit of detection value. The analyte concentrations determined from the pooled sample are provided. * Reference ranges are values published by established organizations (United States National Academy of Medicine) and national reference clinical laboratories (Mayo Clinical Medical Laboratory, ARUP Laboratories, Salt Lake City, UT, USA; Quest Diagnostics, Seacaucus, NJ, USA.