Vitamin D tablet assay (Naturemade 2000 IU) on a Kinetex 2.6 µm Biphenyl, 150 x 4.6

LC Conditions

Column

Kinetex 2.6 µm Biphenyl 100 Å, LC Column 150 x 4.6 mm, Ea

Brand

Kinetex

Part No

00F-4622-E0

Phase Name

Biphenyl

Elution Type

Isocratic

Mobile Phase

A: 0.1% TFA

B: Acetonitrile

Gradient Profile

Step No.

Time(min)

%A

%B

1

0

35

65

Flow Rate

1.75 mL/min

Temperature

40°C

Detection

UV-Vis Abs.-Diode Array (PDA) @ (22°C)

Detection Info

Sample Notes

Sample preparation: small tablets (<400 mg) 1. Grind tablet into powder and transfer to a 2 mL dSPE tube (KS0-8916) 2. Spike in 20 µL of triphenylene internal standard (1 mg/mL) and standard additions (if applicable) 3. Add 800 µL of water 4. Sonicate until dissolved (approx. 5 min) 5. Add 800 µL of acetonitrile 6. Shake for 10 min using mechanical shaker 7. Centrifuge at 15000 rpm for 3 min 8. Aspirate 100 µL of supernatant and transfer to an autosampler vial for analysis Sample preparation: large tablets (>400 mg) 1. Grind tablet into powder and transfer to a 5 mL centrifuge tube 2. Spike in 20 µL of triphenylene internal standard (1 mg/mL) and standard additions (if applicable) 3. Add 2 mL of water 4. Sonicate until dissolved (approx. 5 min) 5. Add 400 mg of Quechers salt (AH0-9044) 6. Add 2 mL of acetonitrile 7. Shake for 10 min using mechanical shaker 8. Centrifuge at 6000 rpm for 3 min 9. Aspirate 100 µL of supernatant and transfer to an autosampler vial for analysis