ISSN:
1040-7685
Keywords:
Azo-t-butane
;
cross-linking
;
immobilization
;
capillary columns
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The ability of commercially available azo-t-butun (ATB) to facilitate immobilization of polysiloxane stationary phases in capillary columns deteriorates upon storage. Aged ATB produces columns with high bleed, solute retention shifts, erratic immobilization efficiency, and high activity. This deterioration is accelerated in the presence of light, suggesting free radical processes are involved. The loss of certain lowlevel impurities, which act as free radical transfer agents or radical sinks, may be responsible for the performance change. Regeneration can often temporarily be accomplished using platinum catalyzed reduction with trichlorosilane. The addition of small amounts of toluene or other radical transfer agents to aged ATB moderates the cross-linking process, allowing the reproducible production of columns with good immobilization efficiency, excellent intertness, low thermal bleed, and proper polarity.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mcs.1220040307
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