The
first presentation is entitled “Advantages of Reduced Surface Activity (RSA)
Glass Autosampler Vials for Basic Solutes.” In this study, our acclaimed RSA™
autosampler vials were compared with those of a market leading manufacturer
based on conventional borosilicate glass. A variety of test solutes were
assayed at different time intervals and concentrations using both vial types.
The results of the study led to a number of interesting conclusions. First,
only solutes containing basic functional groups showed any loss in peak area
after a given time interval had elapsed, suggesting that interaction with silanols
on the glass surface was responsible for the change. Second, the peak area loss
was found to be drastically lower when using the RSA vials vs. the ordinary
vials (see Fig. 1), which is believed to be due to the mostly silanol-free
surface of the former. Third, the effect was more significant at early time
intervals and leveled off after about 4 hours. This effect could lead to
problems with precision as well as accuracy if different peak areas were
obtained for consecutive injections in an analysis.
In the
second presentation “Separation of 1,3-Dimethylamylamine and Other Polar
Compounds in Dietary Supplement Formulation Using Aqueous Normal Phase
Chromatography with Mass Spectrometry,”
we use the Diamond Hydride™ HPLC column to separate hard to retain analytes. In
a workout supplement called Jack3d®, each polar compound is retained and
separated without the use of ion pair agents, making the method suitable for
LC-MS. One ingredient (1,3-Dimethylamylamine) is controversial in
terms of safety for consumption and has already been banned in a number of
countries. As more data is accumulated for demonstrating the potential hazard
of this compound, a need will arise for accurate and reliable quantitation in a
variety of matrices. Therefore the Diamond Hydride™ column can play a
significant role in these analyses.
A
technical program of the poster sessions is available here. We
look forward to seeing you at the symposium this year!
Figure 1. Percent recovery of 5.00 ppm cetylpyridinium
chloride solution at time intervals of 1 hour each for 4 hours. Both vial types
are compared.
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