Derivatization following hollow-fiber microextraction with tetramethylammonium acetate as a dual-function reagent for the determination of benzoic acid and sorbic acid by GC

Abstract

Derivatization at the injection port following hollow-fiber-based liquid-liquid-liquid microextraction with tetramethylammonium acetate as a dual-function reagent, i.e. an acceptor and derivatization reagent, for the determination of benzoic acid (BA) and sorbic acid (SA) in real samples by GC was developed. BA and SA were extracted from aqueous samples to an organic phase impregnated into the pores of the hollow fiber wall, and then back-extracted to the acceptor solution located inside the lumen of the hollow fiber. Upon injection, the extracted analytes were quantitatively derivatized to their methyl esters with tetramethylammonium acetate in the GC injection port. Several parameters related to the derivatization and extraction efficiency were optimized. The linearity was satisfactory over a concentration range of 0.1-50 mg/L with r > 0.993 for both analytes. The LODs were 2.0 μg/L for SA and 20 μg/L for BA. The recoveries (83-116%) and precisions (RSDs of 1.2-11.4% (n = 3)) were examined by analyzing real spiked samples. The enrichment factors of BA and SA were 300 and 425. The results demonstrated that this is a simple, rapid, accurate, and sensitive method for the determination of BA and SA in various samples.

Evaluation of microextraction by packed sorbent, liquid–liquid microextraction and derivatization pretreatment of diet‐derived phenolic acids in plasma by gas chromatography with triple quadrupole mass spectrometry

“…TBAH produces higher normalized areas for the four studied analytes than TBACl, which is also true for the net areas, given by better reaction yield. The formation of an ion pair between TBA salt and the acid conjugate base is decomposed inside the heated GC injection port to produce the tributylammonium and a butyl ester derivative , which is aided by the use of packed liners to increase the contact surface. It is more difficult to establish the TBA‐conjugate base ion pair using TBACl than TBAH, requiring higher salt concentrations and temperatures, which lead to a secondary pyrolysis reducing dramatically the liner lifespan.…”

Solid-phase extraction using bis(indolyl)methane-modified silica reinforced with multiwalled carbon nanotubes for the simultaneous determination of flavonoids and aromatic organic acid preservatives

“…Flavonoids have gained great interest in the last decade because of their significant antioxidant activities, their radical scavenging properties and their ability to restrain platelet aggregation and low‐density lipoprotein oxidation and widely existed in some drinks such as grape drinking and red wine. Moreover, aromatic organic acids have increased significantly in production of processed and convenient foods because they exhibit inhibitory activity against a wide range of fungi, yeasts, molds, and bacteria . However, excessive addition of these preservatives may be harmful to consumers and cause some adverse effects such as allergic contact dermatitis, convulsion, and hives in humans .…”

“…Moreover, aromatic organic acids have increased significantly in production of processed and convenient foods because they exhibit inhibitory activity against a wide range of fungi, yeasts, molds, and bacteria [28,29]. However, excessive addition of these preservatives may be harmful to consumers and cause some adverse effects such as allergic contact dermatitis, convulsion, and hives in humans [30].…”

Assessment of Sorbate and Benzoate Content in Mustard, Ketchup and Tomato Sauce by Sub-Minute Capillary Electrophoresis

“…Despite the high sensitivity, the liquid chromatography methods present some drawbacks, especially in regard to the acquisition and operational costs, and in general, they are not in agreement with the concept of green analytical chemistry. Also, other methods are reported in the literature, including gas chromatography (3,(13)(14)(15) and capillary electrophoresis (CE) (16)(17)(18)(19). Therefore, it is important and essential to developing methods that are simple, quick, and economical to determine sorbate and benzoate in food products.…”