Skip to main content

Table 5 Solid spectrophotometric determination of ascorbic acid in various samples (n = 3, P = 0.95)

From: Silica-titania xerogel doped with Mo,P-heteropoly compounds for solid phase spectrophotometric determination of ascorbic acid in fruit juices, pharmaceuticals, and synthetic urine

Sample

(AA declared content)

Found with solid phase spectrophotometry

(RSD,  %)

Found with titrimetric method (RSD,  %)

Synthetic urine spiked with 20 mg L−1 of ascorbic acid

20.46 ± 2.34 mg L−1 (6.7)

19.58 ± 0.81 mg L−1 (2.4)

Naturetto vitamin tablets

(7 mg/tablet)

7.29 ± 0.81 mg/tablet (6.5)

7.00 ± 0.20 mg/tablet (1.7)

Naturino vitamin tablets

(11.25 mg/tablet)

10.43 ± 0.95 mg/tablet (5.3)

10.73 ± 0.55 mg/tablet (3.0)

Orange juice

(200 mg L−1)

179.30 ± 21.50 mg L−1 (7.0)

175.00 ± 10.66 mg L−1 (3.6)

Blood orange juice

(90 mg L−1)

101.67 ± 12.73 mg L−1 (7.3)

NDa

  1. aNot determined, due to red color of the sample interfering with establishing titration endpoint