Selective Determination of Diphenhydramine in Compound Pharmaceutical Containing Ephedrine by Flow-Injection Electrochemiluminescence

Abstract

The development of compounding drugs by mixed Chinese traditional and western medicine for treating disease has became important in China. Chinese tradition medicine was crude drugs with low side-effect and long-effect, but western medicine as chemical medicine usually effect in a short time and the aftereffect can be reversed of using Chinese traditional medicine. Many clinical and pharmacological experiments have proved that compounding drugs has the advantages of improving curative effects, reducing deleterious side-effects and shortening the period of treatment in relation to using Chinese traditional or western medicine separately.Diphenhydramine, 2-(diphenylmethoxy)-N,N-dimethylethanamine hydrochloride (DPH), a histamine H 1 -receptor antagonist is widely used as antiallergic, antiemetic and antitussive drug in many pharmaceutical preparations. 1 DPH is usually given in a preparation of tablet or drops or as an injection, either alone or in combination with other drugs (i.e. ephedrine, EPH). EPH is generally prepared from Ma huang, which is a traditional Chinese medicine derived from Ephedrae plant. It is used as a pharmaceutical for exciting the central nervous system, the systole of blood vessels, and the lysis of spasm of bronchial smooth muscles. Excessive DPH use could bring about symptoms of phrenitis, tic, tremor, low blood pressure and decompensation. As for babies and young children, it also could result in exciting them easily and causing hallucinations. Mixing DPH with EPH to create a compound drug can exert the good qualities of two drugs and reduce the side-effects of using DPH alone. In the pharmaceutical compound of DPH and EPH, the amount of DPH must be accurately monitored to avoid possible damage to human health due to an unreasonable mixture. Many analytical methods have been proposed for determining DPH in pharmaceutical samples including titrimetry, 2 fluorophotometry, 3 electrochemical analysis 4 and spectrophotometry, 5,6 gas chromatography, 7 HPLC 8,9 and capillary electrophoresis. 10,11 Indeed, the spectrophotometry and HPLC are used as a pharmacopoeial method. 8,12 Nevertheless, the spectrophotometric methods are time consuming, especially for compounding a sample without prior separation; and those instruments are relatively high in cost. Additionally, these methods usually require extraction and complicated pretreatment procedures prior to analysis, resulting in use of some toxic reagents and excessive operation. Accordingly, to develop a rapidly and conveniently quantificational method of DPH in a pharmaceutical compound containing EPH has become a significant work.Flow injection analysis (FIA) is well established as an excellent technique for rapid automated quantitative analysis that combines on-line chemical and physical sample treatments with a range of flow-through detection systems in an enclosed, continuous flow environment.13 FIA does not require high cost equipment to overcome shortages of instruments in places where HPLC instruments are not available. On the other han...

Continuous Flow Injection Analysis Method for the Determination of a Drug Diphenhydramine Hydrochloride by Using Phosphomolybdic Acid

“…It's one of the antihistamines and falls into the category of the first generation of antihistamines 2,3 .It's used alone Published Online First: January, 2024 https://doi.org /10.21123/bsj.2024.8926 P-ISSN: 2078-8665 -E-ISSN: 2411 Baghdad Science Journal or in combination with other medicine 4 .Diphenhydramine hydrochloride is prescribed to relieve allergy symptoms , to treat motion sickness, as an anti-emetic and anti-couch ,in cases of bee stings and skin itching and to treat some cases of runny nose and eyes 5 . There are several methods for estimating diphenhydramine hydrochloride in literature; we mention some of them: spectrophotometric methods 6,7 , chromatographic methods [8][9][10][11] , flow injection 12,13 and potentiometric methods 14 . In this study, a new method was introduced within the continuous flow injection analysis technique [15][16][17][18] ,using homemade cells [19][20][21][22] , which depends on fluorescence or turbidity [23][24][25][26] as it is an easy, simple, sensitive, safe and inexpensive method to control the quality of DPH-containing drug tablets using homemade Ayah 6S×1-ST-2D solar cell CFI analyzer 27 , which has been successfully used in the determination of some drugs and some elements 28 .…”