Analysis ephedrine

This experiment describes the quantitative analysis of the asthma medication Quadrinal for the active ingredients theophylline, salicylic acid, phenobarbital, ephedrine HGl, and potassium iodide. Separations are carried out using a Gi8 column with a mobile phase of 19% v/v acetonitrile, 80% v/v water, and 1% acetic acid. A small amount of triethylamine (0.03% v/v) is included to ensure the elution of ephedrine HGl. A UV detector set to 254 nm is used to record the chromatogram. 

Fan et al. [106] developed a high performance capillary electrophoresis method for the analysis of primaquine and its trifluoroacetyl derivative. The method is based on the mode of capillary-zone electrophoresis in the Bio-Rad HPE-100 capillary electrophoresis system effects of some factors in the electrophoretic conditions on the separation of primaquine and trifluoroacetyl primaquine were studied. Methyl ephedrine was used as the internal standard and the detection was carried out at 210 nm. A linear relationship was obtained between the ratio of peak area of sample and internal standard and corresponding concentration of sample. The relative standard deviations of migration time and the ratio of peak area of within-day and between-day for replicate injections were <0.6% and 5.0%, respectively. 

Ephedrine (17) was known to give coloured products on exposure to sunlight. When a 1 % solution was irradiated with UV light from a 30 W tube the solution became coloured and colourless needle-shaped crystals separated. With prolonged exposure, the crystals redissolved as the solution darkened to an intense brown. On analysis, the crystalline compound was identified as the oxazolidine (18). This compound was known to be formed by reaction between ephedrine and benzaldehyde, so it was assumed that the primary photodegradation product of the drug was benzaldehyde [27]. 

Despite the high sensitivity of the methods for chiral resolution described in Section IV.D.4, more direct methods are afforded by NMR spectroscopy, especially for the products of synthesis. Ephedrine (179), pseudoephedrine (180a) and its Me ether (180b) yield stable epimeric N — BH3 adducts on treatment with borane. The configuration of the nitrogen moiety was established by NMR, taking into account the conformational analysis of the molecule392. 

As shown in Fig. 1.21, a series of di- and tri-thiols were mixed under conditions suitahle for disulfide formation and exchange, and allowed to evolve in the presence of an ephedrine template. HPLC-MS analysis of the library mixture after equilihrium had been reached allowed the identification of two heterotetrameric receptors with high (K = ICfi) affinity for ephedrine in borate buffer, although it is not clear whether these were in fact the best binders in the library. 

Johnson, Elliot and Penning introduced this reagent, easily made from /-ephedrine, for 31P-NMR analysis of alcohols and amines40. The method for amines is simpler as the reaction with alcohols requires butyllithium. 

Substituted chiral aldehydes can be derivatized with naturally occurring (1/ ,2S)-ephedrine to give oxazolidines, UC- and H-NMR analysis allows determination of the enantiomeric excess and in simple cases the absolute configuration of the analyzed aldehyde6. Very mild reaction conditions are required. 

Acids and bases. These can be converted to various salts. For example, the absolute configuration of dimethyl (M)-5,6,8,10-tetramethyl-l,2-heptalenedicarboxylate (p 404) was determined by X-ray analysis of its (+)-ephedrine salt84, and the absolute configuration of Troger s base (p 404) by X-ray analysis of a salt with an acid of known configuration87. 

Pumera and coworkers [17] exploited (3-cylodextrin as chiral selector for the enantiomeric resolution of ephedrine, pseudoephedrine, and ibuprofen in NCEC. Male and Luong [23] described chiral analysis of three neurotransmitters (norepinephrine, epinephrine, and isoproterenol) by NCE using 25 mM... 

Letter to the Editor, A procedure for eliminating interferences from ephedrine and related compounds in the GC/MS analysis of amphetamine and methamphetamine, J. Anal. Toxicol., 76 109... 

H. W. Schultz and C. Paveenbampen, Quantitative GLC analysis of theophylline, ephedrine hydrochloride and phenobarbital suspension, J. Pharm. Sci., 62 1995 (1973). 

G. V. Failonde and S. N. Joshi, Analysis of a drug preparation containing nosapine, ephedrine hydrochloride and chlorpheniramine maleate by thin layer chromatography, Indian Drugs, 23 515 (1986). 

However signs do change with the "handedness" of the natural isomer so a higher level of distinction is achieved using CD or polarimetric detection. An enormous advantage is derived from the fact that achiral excipients, such as lidocaine, procaine, and benzocaine, often deliberately added to illicit drug preparations to complicate the chromatographic identifications of amphetamine and methamphetamine, present no interference problem whatsoever to CD detection. ORD detection was developed for the analysis of mixtures of pseudoephedrine and ephedrine [47], which because of the connection between anomalous ORD and CD, should be applicable to CD detection in the UV. 

There are two chirality centers, so the formula predicts a total of four stereoisomers. However, each of the chirality centers has identical groups attached to the carbon, so fewer than four stereoisomers actually exist. The analysis can be conducted in the same manner as was done previously for ephedrine. We start by drawing one of the stereoisomers, the (2/ ,37 )-isomer for example. Then the mirror image of this, the (25,35 )-stereoisomer is drawn. These two compounds are nonsuperimposable mirror images—enantiomers. 

In New Zealand, herbal ecstasy is a term used for many different herbal formulations, none of which contains ecstasy. Some of the names for these herbs (which can be sold in stores) include The Bomb , Reds , and Sublime . Analysis of The Bomb showed substantial amounts of ephedrine the Ministry of Health in New Zealand removed it from the market. Some symptoms associated with herbal ecstasy include headache, dizziness, palpitation, tachycardia, and raised blood pressure. Thus, in countries where the term herbal ecstasy is commonly used, it is important that those who see patients who have taken herbal ecstasy should not confuse it with ecstasy, as toxicity and medical management may be quite different (133). 

F. J. J. Leusen, H. J. Bruins Slot, J. H. Noordik, A. D. van der Haest, H. Wynberg, and A. Bruggink, Reel. Trap. Chim. Pays-Bas, 111, 111 (1991). Towards a Rational Design of Resolving Agents. Part IV. Crystal Packing Analysis and Molecular Mechanics Calculations for Five Pairs of Diastereomeric Salts of Ephedrine and a Cyclic Phosphoric Acid. 

Potapov, V.M. Demianovich, V.M. Terentiev, A.P. Spectropolarimetric analysis. IV. Polarimetric analysis of ephedrines and pseudoephedrines in their mixtures. Zh. Anal. Khim. 1964, 19, 254-257. 

Ephedra was also sold in combination with many other herbs in obscure combinations. Labels frequently listed 10 or 15 different herbs, but, analysis usually disclosed only the ephedra alkaloids and caffeine as present in sufficient quantities to be physiologically active. After several well-publicized accidental deaths, products clearly intended for abuse, such as herbal ecstasy, and other look-alike drugs (products usually containing ephedrine or phenylpropanolamine designed to look like illicit methamphetamine, but in concentrations higher than recommended by industry or the FDA) were withdrawn from the market. Labels on these products were frequently misleading. For example, one might suppose that a product called Ephedrine 60 contained 60 mg of ephedrine when, in fact, the actual ephedrine content was 25 mg. 

Shekelle PG, Hardy ML, Morton SC, et al. Efficacy and safety of ephedra and ephedrine for weight loss and athletic performance a meta-analysis. JAMA 2003 289 1537-1545. 

Gas Chromatography-Mass Spectrometry. A positive screening result for amphetamine or methamphetamine (or MDA, MDEA, and MDMA) obtained by immunoassay is confirmed by GC-MS analysis of the urine specimen. A GC-MS method for amphetamine and methamphetamine that can be adapted to include MDA, MDMA, and MDEA is included in the Chapter 34 Appendix that is found on this book s accompanying Evolve site (http //evolve.elsevier.com/ Tietz/textbook/). With this method, it should be noted that specimens containing ephedrine or pseudoephedrine occasionally have been reported to test positive for methamphetamine when 4-carbethoxyhexafluorobutyryl chloride (4-CB) is used as a derivatizing reagent. ... 

Shekelle, P., Hardy, M., Morton, S., Maglione, M., Mojica, W., Suttorp, M., Rhodes, S., Jungvig, L., and Gagne, J. 2003a. Efficacy and safety of ephedra and ephedrine for weight loss and athletic performance A meta-analysis. JAMA 289, 1537-1545. 

Yamasaki et al. applied gas chromatography to the separation and quantitative analysis of the alkaloids in some Ephedra species collected around the Himalayas. A satisfactory separation of the alkaloids and quantitative determination of L-ephedrine and D-pseudoephedrine was achieved using oxazolidine formation with acetone. ... 

In order to determine ephedrine in aerosols, Lawless et al. expired the aerosol through a piece of stainless-steel tubing into a 10 ml volumetric flask containing acetone. The volumetric flask was brought to volume and an aliquot injected for the gas chromatographic analysis on a 1.15 % SE-30 packed column at 171°C. Over 99.5 % of the amount of ephedrine present in the aerosol could be determined by this method. 

Beckett and Wilkinson developed a method for the identification and estimation of ephedrine and its congeners in urine. Urine samples of 1-5 ml were acidified and extracted with diethyl ether to remove neutral and acidic compounds. The urine was then made alkaline and the amines were extracted with diethyl ether. This extract was used after concentration for gas chromatographic analysis. Because ephedrine and pseudoephedrlne could not be separated as such, their acetone derivatives were prepared1. The retention times of some ephedrines... 

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