Erythrosin B CAS 16423-68-0

Accurately draw an appropriate amount of solution containing meclofenoxate hydrochloride and place it in a 10 mL colorimetric tube, add 3.00 mL0.5 mmol/L erythrosine B solution and 2.0 mL pH2.6 Clark-Lubs buffer solution accurately in turn, add distilled water Make up to volume and shake well. Prepare reagent blank solution at the same time, and measure the absorbance A of the solution at 554 nm with the reagent blank solution as a reference.

The maximum absorption wavelength of erythrosine B is 520nm, and the maximum absorption wavelength of the ionic association formed between erythrosine B and meclofenoxate hydrochloride is at 554 nm. Select 554m as the measurement wavelength.

The influence of pH value on the system was investigated, and it was found that when the pH was between 2.2 and 3.0, the absorbance at 554nm was the largest and stable, and when the pH was greater than 3.0 or less than 2.2, the absorbance decreased. Therefore, the pH26 Clark-Lubs buffer solution was selected in the subsequent tests, and it was determined through experiments that the most suitable solution was 2.0 mL. For 50ug meclofenoxate hydrochloride, the absorbance of the erythrosine B solution in the range of 2.50-4.00mL is the largest: the amount is too small to react completely, and the amount is too large to be unfavorable for the reaction and the absorbance is weakened. Therefore, 3.0 mL of 0.5 mmol/L erythrosin B solution was used. The absorbance of the system is stable at room temperature of 20-30°C.

For 50ug meclofenoxate hydrochloride under the experimental conditions, the allowable addition amount (in mg, relative deviation less than 5%) of co-existing components is respectively glucose (4), D fruit field, maltose (5), sucrose (7), Lactose (10), Starch (20). This shows that these components that may exist in the meclofenoxate preparation have no influence on the determination of meclofenoxate. Take 10 bottles of Su Rui Suo (Meclofenoxate Hydrochloride for Injection) in the market or take 10 capsules of Jiannaosu (Meclofenoxate Hydrochloride) in the market, and drain the contents. Mix well, and after accurate weighing, accurately weigh one-tenth of the total mass, add a small amount of water to dissolve, and dilute to 1 L (concentration: 100 mg/L) with water to obtain a sample treatment solution. The test results were consistent with those obtained by the Chinese Pharmacopoeia method.