Keywords: ephedrine; Visible and ultraviolet spectrophotometry
Objective: To explore a new method for the determination of ephedrine hydrochloride injection in order to meet the needs of clinical medication more quickly and accurately. Methods: Ephedrine hydrochloride injection from different manufacturers and batches was used as the test sample, and standard ephedrine was used as the control. The maximum absorbance of reference material was measured by ultraviolet spectrophotometer, and the relationship between concentration and absorbance was obtained, and its regression equation was obtained, and its recovery rate was determined. The content obtained was compared with the method of Pharmacopoeia. Results: The maximum absorption wavelength was 256 1 nm, the concentration and absorption of ephedrine hydrochloride were linear in the range of 0.2 ~ 1.2 mg/ml (r = 0.999 9), and the average recovery rate was (100.3 1.6544). Conclusion: UV spectrophotometry can be used as a new method to determine the content of ephedrine hydrochloride injection.
China Library Classification. ]r 974.3； O 657.32[ Document ID] a
[ArticleNo.]1000-2200 (2000) 05-0380-02
Ephedrine hydrochloride is an adrenergic drug. At present, there are three methods to determine the content of ephedrine hydrochloride and its preparations: nonaqueous titration [1], silver titration [1] and neutralization method [2]. In this paper, the content of ephedrine hydrochloride injection [3] was determined by ultraviolet spectrophotometry [1], and compared with the reported nonaqueous titration method in Pharmacopoeia 1995.
1 materials and methods
1. 1 instrument Du-640 ultraviolet spectrophotometer (Beckman company, USA).
1.2 ephedrine hydrochloride reference substance, ephedrine hydrochloride injection (Shanghai Xinyi Pharmaceutical Factory, batch number 95 120 1- 1, 951201-2; Wuxi seventh pharmaceutical factory, batch number 960 1 17- 1, 960112, 960610; The specification is 1 ml: 50mg).
1.3 ultraviolet absorption spectrum determination method of ephedrine hydrochloride (1): take a proper amount of ephedrine hydrochloride reference substance and dissolve it in distilled water to make a solution of 0.6 mg/ml. Using distilled water as blank, scanning at the wavelength of 230~300 nm, the maximum absorption is at the wavelength of 256 1 nm, so 256 nm is used as the measurement wavelength. (2) Drawing of standard curve: accurately weigh 50mg 105℃ and dry ephedrine hydrochloride reference substance to constant weight, put it in a 25 ml volumetric flask, add water to dissolve and dilute to scale, and shake well. Accurately measure 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 ml of liquid medicine, put them in 10 ml volumetric flask, dilute them with water to scale, shake them evenly, take water as blank, and measure the absorbance at 256 nm respectively. The results show that there is a good linear relationship between concentration and absorbance in the concentration range of 0.2 ~ 1.2 mg/ml. The regression equation is: a = 0.8256c+0.01.20 (r = 0.9999, n = 6). (3) Stability test: Determine the absorbance of each solution under item (2) at 0, 1, 2, 3, 4, 8, 16 and 24 h after preparation, and the results are almost unchanged. (4) Recovery rate test: Accurately weigh about 25 mg of ephedrine hydrochloride reference substance dried to constant weight at 105℃, put it in a 50 ml volumetric flask, dissolve it in water and dilute it to scale, take water as a blank, measure the absorbance according to law at the wavelength of 256 nm, and find out the recovery rate. (5) Sample determination: take different batches of ephedrine hydrochloride injection, accurately measure 1 ml, put them in 100 ml volumetric flasks respectively, add water to dilute to scale, shake well, take water as a blank, measure the absorbance at 256 nm, calculate its content, and compare the results with those recorded in the non-aqueous version of China Pharmacopoeia 65,438+0995.
The statistical method of 1.4 adopts paired t test.
Two results
See table1for the test results of ultraviolet spectrophotometry recovery rate; See Table 2 for the comparison with the results of determination of ephedrine hydrochloride injection in samples by Pharmacopoeia method.
Table 1 Recovery Test Results (n=5)
Added quantity (mg) Measured quantity (mg) Recovery rate (%) s (%)
1 26.40 26.42 100.08
2 24.80 25.20 10 1.6 1
3 25.20 25.08 99.52 100.3 1 1.02
4 24.30 24.57 10 1. 1 1
5 25.00 24.8 1 99.24
Table 2 Comparison of two methods (ni =15; s)
Determination method marked quantity (%) SD TD P
Ultraviolet spectrophotometry
Pharmacopoeia method100.171.07
100. 18 0.48 0.0 1 0.80 0.02 >0.05
3 discussion
Ephedrine hydrochloride injection is a controlled drug stipulated by the Ministry of Health. In order to ensure the accuracy and effectiveness of patients' medication and prevent the loss of ephedrine hydrochloride raw materials in the production of this kind of drugs, it is particularly important to determine the content of ephedrine hydrochloride drugs quickly, simply and accurately. The traditional determination method of this product is not only complicated in operation, but also consumes a lot of reagents. Mercury acetate reagent in non-aqueous titration is harmful to human body and pollutes the environment.
Ephedrine belongs to β -adrenoceptor agonist, which can directly or indirectly excite adrenoceptor. It has a strong effect on cardiovascular system, bronchial smooth muscle and central nervous system. It is widely used in clinic and the dosage requirement is very accurate, so it is more important to determine its content accurately and quickly. In particular, "Ephedrine Hydrochloride Nasal Drops", commonly used in clinic, is a self-made drug in hospital, with short validity period and frequent preparation. On the basis of its accuracy, it is of certain significance to quickly determine and ensure the supply of clinical drugs in time and guide clinical medication.
There was no significant difference between the two methods (P > 0.05), which indicated that ultraviolet spectrophotometry could be used as a new method for the determination of ephedrine hydrochloride injection. This method is simple, rapid, accurate and reproducible.
About the author: Mars (1967-), female, from Lingbi County, Anhui Province, is a pharmacist.
[References]
[1] People's Republic of China (PRC) * * * and Pharmacopoeia Committee of Ministry of Health of China. China Pharmacopoeia II [M]. Guangzhou: Guangdong Science and Technology Press,1995+08,693 ~ 694.
[2] People's Republic of China (PRC) * * * and the Ministry of Health Bureau of Pharmacy. China pharmaceutical preparation standard * western medicine preparation [M]. Beijing: China Medical Science and Technology Press, 1996.438+066 ~ 167.
Bear, Jianjie, Zhou. Determination of plasma concentration of mifepristone by ultraviolet spectrophotometry [J]. Journal of Pharmacy of China Hospital, 1998, 18 (6): 262.
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