5. AOACSPDSMethods-2018AwardsV3

129

where A is the absorbance of the test solution at 540 nm; b is the y-intercept of the calibration curve; m is the slope of the calibration curve; V is the total mL of sample solution; W is the weight of sample in mg.

References:

J. AOAC Int . (future issue) AOAC SMPR 2015.015 (Aloe vera) J. AOAC Int . 99 , 318(2016) http://dx.doi.org/10.5740/jaoacint.SMPR2015.015 Posted: February 2019

Table 2018.14A. Preparation of calibration standards

Stock standard solution, mL

Calibration solutions

Water, mL

Concn, mg/mL

Blank

0.0 0.2 0.4 0.6 0.8 1.0

1.0 0.8 0.6 0.4 0.2 0.0

0.0 0.2 0.4 0.6 0.8 1.0

1 2 3 4 5

Table 2018.14B. Peparation of liquid samples mg mL Assay range, % 6000 10 0.03–0.17 1175 10 0.17–0.85 235 10 0.85–4.25 Table 2018.14C. Preparation of powdered samples Sample type mg mL

Assay range, %

Dried juice powders

200

50

5-25

Purified aloe vera (>20%)

50

50

20-100