PMID- 17723654
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20070830
LR  - 20070828
IS  - 1873-4324 (Electronic)
IS  - 0003-2670 (Linking)
VI  - 577
IP  - 1
DP  - 2006 Sep 1
TI  - Simultaneous determination of preservatives in soft drinks, yogurts and sauces by 
      a novel solid-phase extraction element and thermal desorption-gas chromatography.
PG  - 62-7
AB  - A novel solid-phase extraction element combined with thermal desorption-gas 
      chromatography (TD-GC) using a pyrolysis-GC system was applied for the 
      determination of the five preservatives - benzoic acid, sorbic acid, and methyl, 
      ethyl and propyl esters of p-hydroxybenzoic acid - in soft drinks, yogurts and 
      sauces. The extraction element is made of a titanium (Ti) tubing (30 mm x 1.2 mm 
      i.d.x1.6 mm o.d.) coated with a chemically bonded layer of polydimethylsiloxane 
      (PDMS) to a thickness of 500 microm. A sample pH of 2.0, sample volume of 5 ml, 
      extraction time of 45 min with addition of salt (15% m/v NaCl) and TD temperature 
      from 40 to 280 degrees C at a heating rate of 40 degrees Cmin(-1) and maintained 
      at 280 degrees C for 9 min, were selected as optimum extraction and desorption 
      conditions. The linearity of the method was satisfactory over a concentration 
      range of 2-1000 mg L(-1) for benzoic acid and sorbic acid, 0.2-300 mg L(-1) for 
      methyl ester of p-hydroxybenzoic acid, and 0.02-300 mg L(-1) for ethyl and propyl 
      esters of p-hydroxybenzoic acid, and the correlation coefficients were higher 
      than 0.997. The limit of detection ranged from 0.002 to 0.2 mg L(-1). The 
      potential of the proposed method was assessed by applying it to the determination 
      of preservatives in real samples. The recoveries (92-106%) and precisions 
      (R.S.D.s of 0.9-4.6% (n=5)) of the method were examined by analyzing soft drink, 
      yogurt and sauce samples spiked at levels of between 20 and 100 mg L(-1). This 
      simple, accurate and highly sensitive method may be used in the determination of 
      the preservatives in various water-based food samples.
FAU - Wang, Lili
AU  - Wang L
AD  - College of Chemical Engineering and Materials Science, Zhejiang University of 
      Technology, Hangzhou, Zhejiang 310014, PR China. lili_wang89@hotmail.com
FAU - Zhang, Xiao
AU  - Zhang X
FAU - Wang, Yiping
AU  - Wang Y
FAU - Wang, Wei
AU  - Wang W
LA  - eng
PT  - Journal Article
DEP - 20060618
PL  - Netherlands
TA  - Anal Chim Acta
JT  - Analytica chimica acta
JID - 0370534
EDAT- 2007/08/29 09:00
MHDA- 2007/08/29 09:01
CRDT- 2007/08/29 09:00
PHST- 2006/04/08 00:00 [received]
PHST- 2006/06/13 00:00 [revised]
PHST- 2006/06/14 00:00 [accepted]
PHST- 2007/08/29 09:00 [pubmed]
PHST- 2007/08/29 09:01 [medline]
PHST- 2007/08/29 09:00 [entrez]
AID - S0003-2670(06)01306-7 [pii]
AID - 10.1016/j.aca.2006.06.030 [doi]
PST - ppublish
SO  - Anal Chim Acta. 2006 Sep 1;577(1):62-7. doi: 10.1016/j.aca.2006.06.030. Epub 2006 
      Jun 18.