ABSTRACT
The post-column chemiluminescent reaction of six anticholinergic alkaloid compounds with tris(2,2'-bipyridine)ruthenium(III) (Ru(bpy)3(3+)) is applied to microbore high-performance liquid chromatography (HPLC). At flow rates less than 200 microL/min, the capillary mixing cell in which Ru(bpy)3(3+) and the analyte are mixed directly allows for good light detection. In contrast, a diminished signal occurs at these low flow rates with conventional post-column mixing in a tee. Optimal chemiluminescent pH conditions for atropine, scopolamine, dicyclomine, cyclopentolate, cyclobenzaprine, and procyclidine are determined at moderately basic conditions (pH 7 to 9). 2-Butanone is found to be compatible with the chemiluminescent reaction, whereas tetrahydrofuran and propionitrile cause an increase in background noise and a chemiluminescent signal loss. As 2-butanone is more nonpolar than acetonitrile, it assists in the elution of these hydrophobic anticholinergic compounds. Five anticholinergic compounds are resolved successfully with a PRP-1 polymeric column and a slightly basic mobile phase, but a C8 silica column is better suited for the more hydrophobic compounds (cyclobenzaprine, procyclidine, and dicyclomine).
Subject(s)
2,2'-Dipyridyl/analogs & derivatives , Amines/isolation & purification , Cholinergic Antagonists/isolation & purification , Chromatography, High Pressure Liquid/methods , Luminescent Measurements , Organometallic Compounds , Amitriptyline/analogs & derivatives , Amitriptyline/isolation & purification , Atropine/isolation & purification , Butanones , Cyclopentolate/isolation & purification , Dicyclomine/isolation & purification , Hydrogen-Ion Concentration , Indicators and Reagents , Procyclidine/isolation & purification , Scopolamine/isolation & purificationABSTRACT
The separation and detection of five antihistamine drugs commonly found within over-the-counter allergy and cold pharmaceutical products was performed by HPLC with chemiluminescence (CL) detection. Comparable detection limits at 5-10 pmol were found for the antihistamines by both UV at 214 nm and tris(2,2'-bipyridine) ruthenium(III) CL. However, urine samples were found not to generate as large an unretained peak by CL detection as compared to those peaks by UV detection at 214 and 254 nm. For example, the pheniramine peak representing 0.15 microgram/ml was almost totally obscured at 214 nm. Quantitative results received for three antihistamine commercial samples ranged from 4 to 8% error in accuracy when an internal standard was used to compensate for short term detector drift.
Subject(s)
2,2'-Dipyridyl/analogs & derivatives , Chromatography, High Pressure Liquid/methods , Histamine H1 Antagonists/isolation & purification , Organometallic Compounds/chemistry , Ruthenium/chemistry , 2,2'-Dipyridyl/chemistry , Brompheniramine/analysis , Brompheniramine/isolation & purification , Chlorpheniramine/analysis , Chlorpheniramine/isolation & purification , Diphenhydramine/analysis , Diphenhydramine/isolation & purification , Histamine H1 Antagonists/analysis , Luminescent Measurements , Pheniramine/analysis , Pheniramine/isolation & purification , Pyrilamine/analysis , Pyrilamine/isolation & purification , Spectrophotometry, UltravioletABSTRACT
Pyrolysis-gas chromatography is shown to be a rapid straightforward method for the qualitative differentiation of the macrolide antibiotics erythromycin, oleandomycin, troleandomycin, spiramycin and tylosin. Organic salts do not interfere and identification of erythromycin and troleandomycin in commercial products is viable. Spectrophotometric quantitation of these same five antibiotics after reaction with concentrated sulphuric acid is studied at about 470 nm. Reaction conditions such as acid concentration, time and temperature are provided. The sugar moieties of the antibiotics are proposed as the reactive sites. Detection limits are about 0.2-1.0 microg ml-1 [corrected] and analysis of pharmaceutical products should be possible.
