Opium alkaloids derivatization

Bechtel utilized a strong polar stationary phase (HI-EFF 8B) 0.75 % on Chromosorb G HP for the same purpose and succeeded in determining the main opium alkaloids in opium extracts without any derivatization. The relative standard deviation for the individual alkaloids lay between 0.6 t and 8.8 %, and for morphine at 2.3 %. An internal standard was used for the evaluation. On a packed column with a 1 1 mixture of OV-17 and SE-30 (3 % on Varaport 30... 

GC is the method of choice for bioanalysis of opium alkaloids [9, 10], but for the analysis of plant extracts it may be less cOTivenient due to the many less volatile substances co-extracted [11]. The major crmstrain of the GC methods is the conunonly used prior derivatization of the analytes in order to volatilize them, avoid broadening of the peaks in order to achieve easier quantificatirHi. This makes the sample preparatirm complex and increases the costs for the GC method. The coupling GC-MS is often used because of its sensitivity, but the necessity of sample derivatization and the cost of the technique itself are restricting its applicability. 

Although UV is the most widely used detection technique found for the analysis of the major opium alkaloids in different matrices, another optical detection techniques have been found. Luminescence is also a very attractive detection system, due to its low sensitivity but it has been scarcely employed in the analysis of the major opium alkaloids of samples of forensic interest. FLD have been employed for the analysis of a binary mixture of MO and 6-AM based on the derivatization with diazomium salt of aniline at 0°C [121]. It was necessary to optimize all the conditions that affect derivatization (diazonium concentration and reaction time) and those related with the separation (electrolyte concentration, pH, p-CD concentration, organic additives, and separation potential) but good linearity was obtained in the range of 50-2000 ng/mL. 

A number of various derivatization reactions have been used, as shown in Table 14.25. The derivatization has been carried out as off-column or on-column derivatization, mostly in order to give morphine and related alkaloids with phenolic or alcoholic hydroxyl groups better gas chromatographic properties. Especially for quantitative determination of morphine in opium or biological material such derivatization was necessary. Street et al. found, however, that the problem of adsorption of a phenolic alkaloid, such as morphine, because of "active sites" on the solid support could be solved by deactivation of the solid support by treatment of it (diatomaceous earth) with benzoyl chloride in pyridine before coating it with the stationary phase. 

CONTENT OF ALKALOIDS IN OPIUM, OPIUM EXTRACT AND OPIUM TINCTURE34 determined without derivatization on a 3.5 % SE-30 column... 

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