Comparative Study on the Analysis of Lactic Acid in Feminine Wash Using High Performance Liquid Chromatography (HPLC) and Gas Chromatography -Mass Spectroscopy (GC-MS) with Solid Phase Microextraction (SPME)

2008 ◽  
Vol 4 (2) ◽  
Author(s):  
Lourdes P Guidote ◽  
Christa I Dela Cruz ◽  
Kosta Fremielle C Lim
Keyword(s):  
Gas Chromatography ◽  
High Performance Liquid Chromatography ◽  
Lactic Acid ◽  
Liquid Chromatography ◽  
Comparative Study ◽  
Mass Spectroscopy ◽  
Solid Phase Microextraction ◽  
High Performance ◽  
Solid Phase ◽  
Gas Chromatography Mass Spectroscopy

ANTIOXIDANTS FOR EPDM SEALS EXPOSED TO CHLORINATED TAP WATER

2014 ◽  
Vol 87 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Mio Gonokami ◽  
Yoshimasa Yamamoto ◽  
Oraphin Chaikumpollert ◽  
Yoshito Ohtake ◽  
Seiichi Kawahara
Keyword(s):  
Gas Chromatography ◽  
Weight Loss ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Mass Spectroscopy ◽  
High Performance ◽  
Tap Water ◽  
Accelerated Degradation ◽  
Poly Ethylene ◽  
Gas Chromatography Mass Spectroscopy

ABSTRACT A suitable antioxidant for a poly(ethylene-co-propylene-co-5-ethylidene-2-norbornene) (EPDM) seal in tap water applications was determined with respect to volatilization and decomposition of the antioxidants. Seals were prepared by mixing EPDM with 1 phr antioxidant and other ingredients followed by vulcanizing the mixture at 433 K for 20 min. The resulting EPDM seals were immersed into chlorinated water to investigate accelerated degradation. The change in antioxidant content was measured by gas chromatography/mass spectroscopy (GC/MS) and high-performance liquid chromatography (HPLC). The weight loss of amine antioxidants during vulcanization was quite low due to their low volatility and decomposition. Antioxidant weight loss during accelerated degradation depended on both the antioxidant's ability to trap radicals and solubility in chlorinated water.

scholarly journals Analysis of Caffeine, Chlorogenic Acid, Trigonelline, and Volatile Compounds in Cold Brew Coffee Using High-Performance Liquid Chromatography and Solid-Phase Microextraction—Gas Chromatography-Mass Spectrometry

Foods ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1746
Author(s):  
JeongAe Heo ◽  
Koushik Adhikari ◽  
Kap Seong Choi ◽  
Jeehyun Lee
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Chlorogenic Acid ◽  
Volatile Compounds ◽  
Solid Phase Microextraction ◽  
High Performance ◽  
Solid Phase ◽  
Gas Chromatography Mass Spectrometry

This study investigated the non-volatile and volatile compounds in samples of cold brew (CB) coffee, coffee from a coffee shop (CS), ready-to-drink (RTD) coffee, and brewed coffee from a coffee maker (CM). The volatile compounds were identified using headspace solid-phase microextraction with gas chromatography-mass spectrometry, and the samples were treated with high-performance liquid chromatography for the quantification of caffeine, chlorogenic acid, and trigonelline. The results indicate that RTD coffee had the lowest amounts of non-volatile compounds. A total of 36 volatile compounds were semi-quantified; the contents of most volatile compounds in CS and Folgers samples were higher than those in CB and CM samples. The contents of 25 volatile compounds in the CM sample were higher than those in the CB sample. The consumer and instrumental data show that the bitterness intensity was correlated with pyrazines, pyrroles, and guaiacols, whereas the coffeeID intensity was correlated with phenols. Semi-quantification and principal component analysis results show that the extraction method and temperature could influence the volatile compound profiles.

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