王曉青等

摘 要 建立了以乙酸己酯為萃取相、四甲基氫氧化銨（TMAH）為接收相的中空纖維三相液相微萃取結(jié)合進(jìn)樣口衍生化氣相色譜法，同時(shí)測定啤酒中水楊酸、對(duì)羥基苯甲酸、肉桂酸、香草酸、對(duì)香豆酸、阿魏酸等酚酸類物質(zhì)。啤酒中的酚酸被中空纖維膜壁中的乙酸己酯萃取，接著溶于纖維膜內(nèi)堿性的TMAH接收相。取1 μL接收相進(jìn)樣，在進(jìn)樣口酚酸被TMAH衍生化成相應(yīng)的甲酯。對(duì)影響萃取與衍生化效率的主要因素進(jìn)行了優(yōu)化，得到最佳條件：萃取劑為乙酸己酯，衍生化試劑和接受相為5% TMAH溶液，供給相pH=2，NaCl濃度為25%，攪拌速度為References

1 DONG Xia， LI Qi， GU GuoXian. Liquor Making， 2003， 30（6）： 63-65

董 霞， 李 崎， 顧國賢. 釀酒， 2003， 30（6）： 63-65

2 Vanbeneden N， Delvaux F， Delvaux F R. J. Chromatogr. A， 2006， 1136（2）： 237-242

3 Floridi S， Montanari L， Marconi O， Fantozzi P. J. Agr. Food Chem.， 2003， 51（6）： 1548-1554

4 Alonso García A， Cancho Grande B， Simal Gándara J. J. Chromatogr. A， 2004， 1054（12）： 175-180

5 Citová I， Sladkovsky R， Solich P. Anal. Chem. Acta， 2006， 573-574： 231-241

6 Proestos C， Sereli D， Komaitis M. Food Chem.， 2006， 95（1）： 44-52

7 Nur B A B， Ahmad M， Bahruddin S. Anal. Chem. Acta， 2012， 724： 59-66

8 TAN XiaoWang， WEI RuiPing， SONG YanXi， YI GuYang. Chinese J. Anal. Chem.， 2012， 40（9）： 1409-1414

譚小旺， 魏瑞萍， 宋燕西， 易谷洋. 分析化學(xué)， 2012， 40（9）： 1409-1414

9 Peng J F， Liu J F， Hu X L， JiangG B. J. Chromatogr. A， 2007， 1139（2）： 165-170

10 SHAO Yan， ZHANG LiJun， ZHANG ZhanEn. Chinese J. Anal. Chem.， 2011， 39（11）： 1753-1757

邵 焰， 張麗君， 張占恩. 分析化學(xué)， 2011， 39（11）： 1753-1757

11 Sun Y， Wang X Q， Huang Y L， Pan Z F， Wang L L. J. Sep. Sci.， 2013， 36（14）： 2268-2276

12 Wu J M， Lee H K. J. Anal. Chem.， 2006， 78（20）： 7292-7301

13 Sanagi M M， Miskam M， Ibrahim W A W， Hermawan D， AboulEnein H Y. J. Sep. Sci.， 2010， 33（14）： 2131-2139

Derivatization at Injection Port Following Hollow Fiber Microextraction

with Tetramethylammonium Hydroxide for Determination of

Six Phenolic Acids in Beers by Gas Chromatography

WANG XiaoQing1， HUANG YiLei1， SUN Yang2， PAN ZaiFa1， WANG LiLi*1

1（College of Chemical Engineering， Zhejiang University of Technology， Hangzhou 310014， China）

2（Zhejiang Province Institute of Metrology， Hangzhou 310013， China）

Abstract A method of derivatization at injection port following three phase hollow fiber microextraction with tetramethylammonium hydroxide （TMAH） as a dualfunction reagent， for the simultaneous determination of salicylic acid， phydroxybenzoic acid， cinnamic acid， vanillic acid， pcoumaric acid and ferulic acid in beers by gas chromatography was developed. Phenolic acids were extracted from aqueous samples to a thin layer of organic solvent （hexyl acetate） phase impregnated into the pores of the hollow fiber wall， and then back extracted to an acceptor solution （TMAH） located inside the lumen of the hollow fiber. Upon injection， the phenolic acids were derivatized to their methyl esters in the GC injection port. Several parameters related to the derivatization and extraction efficiency were optimized. The optimized conditions were as follows： hexyl acetate was used as the extraction solvent， an aqueous solution of TMAH （5% W/V） was used as the derivatization reagent and acceptor phase， the pH value of donor phase was 2.0， the concentrations of NaCl was 25% W/V， the stirring rate was 500 r/min， the extraction time was 40 min. Under the optimal conditions， the linear range of phenolic acids was 0.50-15.00 mg/L， the limits of detection were 0.05-0.18 mg/L. The proposed method was applied to the determination of the phenolic acids in beers. Vanillic acid， pcoumaric acid and ferulic acid were found in the beer samples， others were not detected. The spiked average recoveries were 90.1%-106.8% and RSD% was less than 5.9%（n=3）. The method is suitable for the determination of phenolic acids in beers.

Keywords Three phase hollow fiber microextraction； Gas chromatography； Injection port derivatization； Tetramethylammonium hydroxide； Phenolic acids

（Received 20 January 2014； accepted 7 March 2014）

This work was supported by the Analysis and Measurement Foundation of Zhejiang Province （No.2013C37067）

摘 要 建立了以乙酸己酯為萃取相、四甲基氫氧化銨（TMAH）為接收相的中空纖維三相液相微萃取結(jié)合進(jìn)樣口衍生化氣相色譜法，同時(shí)測定啤酒中水楊酸、對(duì)羥基苯甲酸、肉桂酸、香草酸、對(duì)香豆酸、阿魏酸等酚酸類物質(zhì)。啤酒中的酚酸被中空纖維膜壁中的乙酸己酯萃取，接著溶于纖維膜內(nèi)堿性的TMAH接收相。取1 μL接收相進(jìn)樣，在進(jìn)樣口酚酸被TMAH衍生化成相應(yīng)的甲酯。對(duì)影響萃取與衍生化效率的主要因素進(jìn)行了優(yōu)化，得到最佳條件：萃取劑為乙酸己酯，衍生化試劑和接受相為5% TMAH溶液，供給相pH=2，NaCl濃度為25%，攪拌速度為References

1 DONG Xia， LI Qi， GU GuoXian. Liquor Making， 2003， 30（6）： 63-65

董 霞， 李 崎， 顧國賢. 釀酒， 2003， 30（6）： 63-65

2 Vanbeneden N， Delvaux F， Delvaux F R. J. Chromatogr. A， 2006， 1136（2）： 237-242

3 Floridi S， Montanari L， Marconi O， Fantozzi P. J. Agr. Food Chem.， 2003， 51（6）： 1548-1554

4 Alonso García A， Cancho Grande B， Simal Gándara J. J. Chromatogr. A， 2004， 1054（12）： 175-180

5 Citová I， Sladkovsky R， Solich P. Anal. Chem. Acta， 2006， 573-574： 231-241

6 Proestos C， Sereli D， Komaitis M. Food Chem.， 2006， 95（1）： 44-52

7 Nur B A B， Ahmad M， Bahruddin S. Anal. Chem. Acta， 2012， 724： 59-66

8 TAN XiaoWang， WEI RuiPing， SONG YanXi， YI GuYang. Chinese J. Anal. Chem.， 2012， 40（9）： 1409-1414

譚小旺， 魏瑞萍， 宋燕西， 易谷洋. 分析化學(xué)， 2012， 40（9）： 1409-1414

9 Peng J F， Liu J F， Hu X L， JiangG B. J. Chromatogr. A， 2007， 1139（2）： 165-170

10 SHAO Yan， ZHANG LiJun， ZHANG ZhanEn. Chinese J. Anal. Chem.， 2011， 39（11）： 1753-1757

邵 焰， 張麗君， 張占恩. 分析化學(xué)， 2011， 39（11）： 1753-1757

11 Sun Y， Wang X Q， Huang Y L， Pan Z F， Wang L L. J. Sep. Sci.， 2013， 36（14）： 2268-2276

12 Wu J M， Lee H K. J. Anal. Chem.， 2006， 78（20）： 7292-7301

13 Sanagi M M， Miskam M， Ibrahim W A W， Hermawan D， AboulEnein H Y. J. Sep. Sci.， 2010， 33（14）： 2131-2139

Derivatization at Injection Port Following Hollow Fiber Microextraction

with Tetramethylammonium Hydroxide for Determination of

Six Phenolic Acids in Beers by Gas Chromatography

WANG XiaoQing1， HUANG YiLei1， SUN Yang2， PAN ZaiFa1， WANG LiLi*1

1（College of Chemical Engineering， Zhejiang University of Technology， Hangzhou 310014， China）

2（Zhejiang Province Institute of Metrology， Hangzhou 310013， China）

Abstract A method of derivatization at injection port following three phase hollow fiber microextraction with tetramethylammonium hydroxide （TMAH） as a dualfunction reagent， for the simultaneous determination of salicylic acid， phydroxybenzoic acid， cinnamic acid， vanillic acid， pcoumaric acid and ferulic acid in beers by gas chromatography was developed. Phenolic acids were extracted from aqueous samples to a thin layer of organic solvent （hexyl acetate） phase impregnated into the pores of the hollow fiber wall， and then back extracted to an acceptor solution （TMAH） located inside the lumen of the hollow fiber. Upon injection， the phenolic acids were derivatized to their methyl esters in the GC injection port. Several parameters related to the derivatization and extraction efficiency were optimized. The optimized conditions were as follows： hexyl acetate was used as the extraction solvent， an aqueous solution of TMAH （5% W/V） was used as the derivatization reagent and acceptor phase， the pH value of donor phase was 2.0， the concentrations of NaCl was 25% W/V， the stirring rate was 500 r/min， the extraction time was 40 min. Under the optimal conditions， the linear range of phenolic acids was 0.50-15.00 mg/L， the limits of detection were 0.05-0.18 mg/L. The proposed method was applied to the determination of the phenolic acids in beers. Vanillic acid， pcoumaric acid and ferulic acid were found in the beer samples， others were not detected. The spiked average recoveries were 90.1%-106.8% and RSD% was less than 5.9%（n=3）. The method is suitable for the determination of phenolic acids in beers.

Keywords Three phase hollow fiber microextraction； Gas chromatography； Injection port derivatization； Tetramethylammonium hydroxide； Phenolic acids

（Received 20 January 2014； accepted 7 March 2014）

This work was supported by the Analysis and Measurement Foundation of Zhejiang Province （No.2013C37067）

摘 要 建立了以乙酸己酯為萃取相、四甲基氫氧化銨（TMAH）為接收相的中空纖維三相液相微萃取結(jié)合進(jìn)樣口衍生化氣相色譜法，同時(shí)測定啤酒中水楊酸、對(duì)羥基苯甲酸、肉桂酸、香草酸、對(duì)香豆酸、阿魏酸等酚酸類物質(zhì)。啤酒中的酚酸被中空纖維膜壁中的乙酸己酯萃取，接著溶于纖維膜內(nèi)堿性的TMAH接收相。取1 μL接收相進(jìn)樣，在進(jìn)樣口酚酸被TMAH衍生化成相應(yīng)的甲酯。對(duì)影響萃取與衍生化效率的主要因素進(jìn)行了優(yōu)化，得到最佳條件：萃取劑為乙酸己酯，衍生化試劑和接受相為5% TMAH溶液，供給相pH=2，NaCl濃度為25%，攪拌速度為References

1 DONG Xia， LI Qi， GU GuoXian. Liquor Making， 2003， 30（6）： 63-65

董 霞， 李 崎， 顧國賢. 釀酒， 2003， 30（6）： 63-65

2 Vanbeneden N， Delvaux F， Delvaux F R. J. Chromatogr. A， 2006， 1136（2）： 237-242

3 Floridi S， Montanari L， Marconi O， Fantozzi P. J. Agr. Food Chem.， 2003， 51（6）： 1548-1554

4 Alonso García A， Cancho Grande B， Simal Gándara J. J. Chromatogr. A， 2004， 1054（12）： 175-180

5 Citová I， Sladkovsky R， Solich P. Anal. Chem. Acta， 2006， 573-574： 231-241

6 Proestos C， Sereli D， Komaitis M. Food Chem.， 2006， 95（1）： 44-52

7 Nur B A B， Ahmad M， Bahruddin S. Anal. Chem. Acta， 2012， 724： 59-66

8 TAN XiaoWang， WEI RuiPing， SONG YanXi， YI GuYang. Chinese J. Anal. Chem.， 2012， 40（9）： 1409-1414

譚小旺， 魏瑞萍， 宋燕西， 易谷洋. 分析化學(xué)， 2012， 40（9）： 1409-1414

9 Peng J F， Liu J F， Hu X L， JiangG B. J. Chromatogr. A， 2007， 1139（2）： 165-170

10 SHAO Yan， ZHANG LiJun， ZHANG ZhanEn. Chinese J. Anal. Chem.， 2011， 39（11）： 1753-1757

邵 焰， 張麗君， 張占恩. 分析化學(xué)， 2011， 39（11）： 1753-1757

11 Sun Y， Wang X Q， Huang Y L， Pan Z F， Wang L L. J. Sep. Sci.， 2013， 36（14）： 2268-2276

12 Wu J M， Lee H K. J. Anal. Chem.， 2006， 78（20）： 7292-7301

13 Sanagi M M， Miskam M， Ibrahim W A W， Hermawan D， AboulEnein H Y. J. Sep. Sci.， 2010， 33（14）： 2131-2139

Derivatization at Injection Port Following Hollow Fiber Microextraction

with Tetramethylammonium Hydroxide for Determination of

Six Phenolic Acids in Beers by Gas Chromatography

WANG XiaoQing1， HUANG YiLei1， SUN Yang2， PAN ZaiFa1， WANG LiLi*1

1（College of Chemical Engineering， Zhejiang University of Technology， Hangzhou 310014， China）

2（Zhejiang Province Institute of Metrology， Hangzhou 310013， China）

Abstract A method of derivatization at injection port following three phase hollow fiber microextraction with tetramethylammonium hydroxide （TMAH） as a dualfunction reagent， for the simultaneous determination of salicylic acid， phydroxybenzoic acid， cinnamic acid， vanillic acid， pcoumaric acid and ferulic acid in beers by gas chromatography was developed. Phenolic acids were extracted from aqueous samples to a thin layer of organic solvent （hexyl acetate） phase impregnated into the pores of the hollow fiber wall， and then back extracted to an acceptor solution （TMAH） located inside the lumen of the hollow fiber. Upon injection， the phenolic acids were derivatized to their methyl esters in the GC injection port. Several parameters related to the derivatization and extraction efficiency were optimized. The optimized conditions were as follows： hexyl acetate was used as the extraction solvent， an aqueous solution of TMAH （5% W/V） was used as the derivatization reagent and acceptor phase， the pH value of donor phase was 2.0， the concentrations of NaCl was 25% W/V， the stirring rate was 500 r/min， the extraction time was 40 min. Under the optimal conditions， the linear range of phenolic acids was 0.50-15.00 mg/L， the limits of detection were 0.05-0.18 mg/L. The proposed method was applied to the determination of the phenolic acids in beers. Vanillic acid， pcoumaric acid and ferulic acid were found in the beer samples， others were not detected. The spiked average recoveries were 90.1%-106.8% and RSD% was less than 5.9%（n=3）. The method is suitable for the determination of phenolic acids in beers.

Keywords Three phase hollow fiber microextraction； Gas chromatography； Injection port derivatization； Tetramethylammonium hydroxide； Phenolic acids

（Received 20 January 2014； accepted 7 March 2014）

This work was supported by the Analysis and Measurement Foundation of Zhejiang Province （No.2013C37067）