Determination of copper and manganese in vitamin-mineral tablets by atomic absorption spectrophotometry

✍ Scribed by Young Soon Chae; James P. Vacik; William H. Shelver

• Publisher: John Wiley and Sons
• Year: 1973
• Tongue: English
• Weight: 409 KB
• Volume: 62
• Category: Article
• ISSN: 0022-3549
• DOI: 10.1002/jps.2600621123

✦ Synopsis

I 10 20 30 , , . I 10 20 30 Figure 2-Chromutogrcim of fritn~~thylsilyl dericutice o f neonrycitr wirh: ( n ) proper unroiirr/ of trimi~fliylsilylrlielietlrglritnirrc~. urrd ( h ) e.xcess /rimetliyl.~ilpldi~~tlrylunririe.

DlSCIJSSlON k a u s c of the many potential sources of difliculties, strict adherence to the reported procedure (2. ?) is recommended to obtain reliable results. These problems are enumerated in Tahle I 1 for convenience; and although each one is of material significance, the following are emphasized:

1. The column must be properly sample conditioned immediately before actual analysis.

2. Thc amount of trimethylsilyldiethylamine reagent added is critical in the formation of the derivative. a$ are the temperature and duration of the reaction (3). When the derivative is properly prepared, the neomycin B peak is symmetrical (Fig. ).

3. Samples should he chromatographed as soon as possible after derivatization or kcpt refrigerated minimally until time of analysis so as to retain optimal stability. T h e x neomycin dcrivativcs degrade readily (3).

In summary, with proper techniques and caution, the GLC method for analysis of the neomycins can be successfully employed. This mcthod has already been shown to be more specific and reliable than the microbiological method (4, 5). Even with GLC instruments offering poor linearity in recovery, satisfactory results can be obtained when they are correlated with authentic cr reference standard calibration mixtures approximating the Concentration level to he determined. This type 01 discussion might prove beneficial in similar analyses of high niolccular wcight oligosaccharides.