The invention discloses a quantitative
analysis method of gamma-
cyclodextrin (gamma-CD) based on a
bromocresol green (BCG) developing method. The measurement method comprises the following experimental steps: (1) a measurement solution is prepared; (2) the light absorption value difference of samples is measured, specifically, a 3 mL of BCG solution with the concentration being 0.35 mmol / L is taken to be added into a 50 mL of brown colorimetric tube, then a 2 mL of gamma-CD solution is added, the constant volume process is conducted to 25 mL through an
acetic acid-
sodium acetate
buffer solution with the pH being being 4.4, after even vibrating, still standing is conducted for 25 min in constant-temperature water
bathing at 30 DEG C, then the absorbancy of the gamma-CD solution is measuredwith the
buffer solution as the reference at 625 nm, in a blank experiment, 2 mL of
distilled water replaces the gamma-CD solution, other experimental operation is the same, and the absorbancy difference (
delta A) is equal to the difference between the sample absorbancy (A) and the absorbancy (A') of the blank solution; and (3) a
standard curve is drawn, specifically, a 1 mmoL / L gamma-CD solution,a 2 mmoL / L gamma-CD solution, a 3 mmoL / L gamma-CD solution, a 4 mmoL / L gamma-CD solution and a 5 mmoL / L gamma-CD solution are added into tubes correspondingly, the absorption value differences of the1 mmoL / L gamma-CD solution, the 2 mmoL / L gamma-CD solution, the 3 mmoL / L gamma-CD solution, the 4 mmoL / L gamma-CD solution and the 5 mmoL / L gamma-CD solution are measured according to the method, andthen a drawing is made with the concentration of CD as the abscissa and the absorbancy differences (
delta A) between the solution of test samples and the blank solution as ordinates to obtain a
positive correlation curve as a gamma-CD
standard curve.