教学工作的资源分享

改进的QuEChERS方法用于鱼肉中孔雀石绿、隐晶绿、结晶紫和隐色结晶紫的快速检测(英文)

学校教务系统

学校教务系统

2014年4月Vol.32 No.4

April 2014 chinesejournalofchromatography 419~425

specialissueforthe 30 thanniversaryofchinesejournalofchromatographyandcelebrationofthe 90 thbirthdayofacademicianlupeichang:arti sp.j.1123.2014.01016 corresponding author.tel:8641184379519, 传真: 8641184379539.email:Liang XM liumy @ mail.Tsinghua.edu.cn (Liu mingyang ).foundation item:nationalnaturalscies

Fast analysis of malachite green,leucomalachite green,crystalvioletandleucocrystalvioletinfissuebasedonamodifiedquecherspron

,圩街2

、东学坊二、郭志牟二、

刘明阳1、2、两良新庙2

(1. collegeofenvironmentandchemistryengineering,Dalian Jiaotong University,Dalian 116028,China; 2.keylaboratoryofseparationscienceforanalyticalchemistry,dalianinstituteofchemicalphysics,Chinese Academy of Sciences,dalynces

abstract:triphenylmethanedyesmalachitegreen (mg ) andcrystalviolet ) cv ) have been used as antimicrobial, antiparasiticandantisepticagentsinaquaculture.however,MG and CV, aswellastheirmetabolitesleucomalachitegreen (lmgandleucocrystalviolet ) lcv ) arepotentialmutagensandcarcinogens.thus, theefficientdeterminationofdyeresiduesisofgreatconcern.consideringthecomplexityoftheaquaticproducts, thesamplepretreatmentissignificantfordecreasingmatrixinterferenceandimprovingdetectionsensitivity.in this study, asimpleandrapidquechersprocedurewasdevelopedandcombinedwithplcanalysisforthesimultaneousdeterminationofthefourdyesinfishtistisussussssse sappliedinhplcanalysistoachievegoodpeakshapeandselectivity.thepretreatmethodinvolvedtheeextractionofdd sfromfishtissueandfd esolidphaseextraction(DSPE ) material. The extraction volume, extractiontimeaswellasdspematerialsweresystematicallyoptimized.theresultsindicatedthatreversedphase/stronganionexchange (sorbentinthedspeprocedurecouldeffectivelyimprovetherecoverycomparedwithconventionalc 18 orc 18 incorporporatedwedtimized conditions, good linearity was achieved in the concentration range of 0􀆰 5-100 mg / L with R2greater

than 0􀆰 998. The recoveries were 73%-91% and the precisions were 0􀆰 66%-5􀆰 41%. The results demonstrated thefeasibility and efficiency of QuEChERS procedure incorporated with HPLC for dye monitoring.Key words: QuEChERS; high performance liquid chromatography (HPLC); malachite green; leucomalachitegreen; crystal violet; leucocrystal violet; fish tissueCLC number: O658 Document code: A Article IC:1000⁃8713(2014)04⁃0419⁃07改进的 QuEChERS 方法用于鱼肉中孔雀石绿、隐色孔雀石绿、

结晶紫和隐色结晶紫的快速检测

朱程云1,2, 魏 杰2, 董雪芳2, 郭志谋2, 刘名扬1,2∗, 梁鑫淼2∗(1. 大连交通大学环境与化学工程学院, 辽宁 大连 116028;2. 中国科学院大连化学物理研究所 分离分析化学重点实验室, 辽宁 大连 116023)摘要:孔雀石绿(MG)和结晶紫(CV)具有抗菌等活性,常被违法用于水产养殖业。 但 MG、CV 及其代谢产物隐色孔雀石绿(LMG)、隐色结晶紫(LCV)具有致癌性。 所以水产品中染料的残留检测是食品安全分析的重要问题。 由于水产品基质复杂,样品前处理尤为重要。 本文发展了一种基于 QuEChERS 技术与高效液相色谱联用的方法,用于鱼肉中 4 种染料的同时检测。 对 QuEChERS 方法中提取剂体积、提取次数以及分散固相萃取材料进行了优化。结果表明反相/ 强阴离子交换材料(C18SAX)能有效提高回收率。 在最优条件下,4 种染料在 0􀆰 5 ~ 100 mg / L 范围色 谱 第 32 卷内线性良好,相关系数均大于 0􀆰 998。

职教二十条

职教二十条

结果表明该方法简单、高效,适合于鱼肉中染料的快速检测。

关键词:QuEChERS;高效液相色谱;孔雀石绿;隐色孔雀石绿;结晶紫;隐色结晶紫;鱼肉组织Malachite green (MG) and crystal violet (CV),which are triphenylmethane dyes, have beenwidely used in aquaculture as antimicrobial, an⁃tiparasitic and antiseptic agents in the past dec⁃ades [ 1, 2]. The major metabolites of MG andCV, leucomalachite green (LMG) and leucocrys⁃tal violet (LCV) possess similar biological charac⁃teristics [3]. Owing to their potential carcinoge⁃nicity, the addition of MG and CV in aquacultureis nowadays absolutely forbidden [1,4]. Howev⁃er, illegal utilization of dyes still exists becausethey are cheap and efficient [5]. Thus, multi⁃res⁃idues determination of dyes in aquatic products isof great significance.Considering the complexity of the matrix inaquatic products, sample pretreatment for decrea⁃sing or eliminating matrix interference and impro⁃ving the detection sensitivity is of great concern.Numerous sample pretreatment methods havebeen established in previous reports [6-11]. Tra⁃ditional liquid⁃liquid extraction method can beeasily realized although it consumes large volumeof solvents [ 6]. Enzyme⁃linked immune sorbentassay (ELISA) [12-14] exhibits good selectivity,but it suffers from false positive results. Solidphase extraction ( SPE ) is a time⁃consumingmethod although the matrix interference can beefficiently removed [15,16]. Molecularly imprin⁃ted solid phase extraction ( MISPE) for samplepreparation reveals good specificity. However,the preparation of MISPE materials is difficult[17,18].QuEChERS, representing the abbreviation of“ quick, easy, cheap, effective, rugged andsafe”, has been acknowledged as a rapid and effi⁃cient pretreatment method for the determinationof hydrophobic pesticides [19-23] as well as vet⁃erinary drug residues [ 24, 25]. The QuEChERSprocedure involves two steps: (i) extraction / par⁃titioning based on the use of NaCl and MgSO4forsalting out, and ( ii) dispersive solid phase ex⁃traction (d⁃SPE) for clean⁃up.

In consideration of the hydrophobicity of MG,LMG, CV and LCV, the introduction of QuECh⁃ERS for sample preparation is advantageous viaextracting dye into the organic layer and cleaning⁃up by d⁃SPE procedure. By optimizing the extrac⁃tion volume, extraction time and d⁃SPE materi⁃als, a specific pretreatment method was devel⁃oped which greatly simplified the sample prepara⁃tion and increased the throughput. With the com⁃bination of the proposed QuEChERS procedureand HPLC method based on XCharge C18 col⁃umn, the simultaneous determination of MG,LMG, CV and LCV in fish tissues was successfullyrealized.1 Experimental

1.1 Chemicals and materials

Malachite green (MG), crystal violet (CV) andleucocrystal violet ( LCV) were purchased fromSigma⁃Aldrich (St. Louis, MO, USA); leucomala⁃chite green (LMG) was obtained from Dr Ehren⁃storfer GmbH (Augsburg, Germany). Acetonitrile(ACN) of HPLC grade was purchased from Merck( Darmstadt, Germany ). Ammonium formate(NH4FA) and formic acid (FA) were purchasedfrom J&K Scientific ( Beijing, China). Water forHPLC mobile phase was purified with a Milli⁃Qsystem (Millipore, Billerica, MA, USA). All oth⁃er reagents were of analytical grade and usedwithout further purification. Reversed⁃phase /strong anion⁃exchange mixed⁃mode material(C18SAX) (40 - 75 μm, particle size) describedin our previous report [26] was selected as d⁃SPEadsorption material. C18, primary secondary a⁃mine ( PSA) materials and XCharge C18 column(3􀆰 0 mm × 100 mm i. d., 5 μm particles) werefrom Acchrom Corp. (Beijing, China).1.2 HPLC conditionsA Hitachi Chromaster HPLC system ( Tokyo,Japan) consisting of 5110 quaternary pump, 5210·420·

第 4 期

ZHU Chengyun, et al: Fast analysis of malachite green, leucomalachite green, crystalviolet and leucocrystal violet in fish tissue based on a modified QuEChERS procedureauto sampler, 5310 column oven and 5430 diode

array detector ( DAD) was employed for HPLCanalysis. The separation was performed on anXCharge C18 column. The column temperaturewas set at 40 ℃ and flow rate was 1 mL / min. Theinjection volume was 20 μL. The mobile phasecomposed of ACN ( A), water ( B ) and 100mmol / L ammonium formate ( pH 3􀆰 0, C). Theelution condition was 0-3 min, 40% A-65% A; 3-8 min, 65% A-75% A, while mobile phase C waskept constant at 20% to obtain a buffer concentra⁃tion of 20 mmol / L. Each dye was determined atthe maximum absorption wavelength: 620 nm forMG, 590 nm for CV, 263 nm for LCV and LMG.1.3 Sample preparation

Cod fish was from local supermarket ( Dalian,China). The skin and bone were removed. Thenthe fish was cut into strips and homogenized. Thehomogenized sample was stored at -20 ℃ in therefrigerator until sample pretreatment.The homogenized cod sample ( 2 g ) wasweighed into a 15 mL polypropylene tube. Then, 2mL of ammonium formate (100 mmol / L, pH 3􀆰 0)and 3 mL of ACN were added. The sample wasshook vigorously to extract the analytes from thematrix. Then 2 g of sodium chloride was added in⁃to the solution for partitioning. The sample wasmixed for about 2 min and centrifuged at 6 000r/ min for 5 min. After that, 1 mL of supernatantand 50 mg of C18SAX material were transferredinto a 2􀆰 5 mL polypropylene tube. The polypropyl⁃ene tube was shook and kept in ultrasonic bathfor 1 min. The mixture was filtered through 0􀆰 22μm membrane. The resulting filtrate was mixedwith ammonium formate (100 mmol / L, pH 3􀆰 0)in the ratio of 4 ∶ 1 ( sample solution ∶ ammoniumformate, v / v). The prepared solution was injec⁃ted into the HPLC system for analysis.1.4 Standard and reagent solutionsThe mixed stock solution with mass concentra⁃tion of 100 mg / L was dissolved by ACN. It wasstored at 4 ℃ and protected against light for lessthan two weeks. The working solution was pre⁃pared through diluting the stock solution with theinitial mobile phase ( ACN ∶ water ∶ 100 mmol / Lammonium formate = 40 ∶40 ∶20, v / v / v). The con⁃centrations of working solution were diluted at0􀆰 5, 1, 5, 10, 25, 50 μg / mL.

2 Results and discussion

2.1 Establishment of chromatographic methodsFig. 1 Structures of malachite green (MG), crystalviolet ( CV), leucomalachite green ( LMG)and leucocrystal violet (LCV)

The resolution of MG, CV, LCV and LMG dyes( structures shown in Fig. 1 ) which are basiccompounds with good selectivity and peak shapeis difficult on traditional C18 columns, especiallyfor LCV and LMG [6,27]. According to the previ⁃ous studies of our group [28,29], XCharge C18column displayed great superiority in the separa⁃tion of basic compounds. Therefore, XCharge C18column was selected for the development of theanalytical method and the mobile phase condi⁃tions was optimized. As shown in Fig. 2a, thecompounds could not be well resolved with 0􀆰 1%(v / v) FA/ H2O in the mobile phase and LMG wasnot eluted within 10 min. Since the utilization ofbuffer solution is advantageous for improvingpeak shape and selectivity, 100 mmol / L ammoni⁃um formate with pH 5􀆰 1 was employed as the mo⁃bile phase additive. The peak shapes were im⁃proved, but LCV and LMG were not well separa⁃ted (Fig. 2b). When the pH value of ammoniumformate was changed to 3􀆰 0, the resolution of thefour dyes was successfully achieved in 8 min withgood peak shapes (Fig. 2c).·421·

色 谱 第 32 卷

Fig. 2 Dyes separated on XCharge C18 columnwith different mobile phases

Mobile phase conditions: a. ACN/ ( 0􀆰 1% FA/ water ); b.ACN/ water/ 100 mmol / L NH4FA, pH 5􀆰 1; c. ACN/ water/ 100mmol / L NH4FA, pH 3􀆰 0.

2.2 Establishment of pretreatment methodThe QuEChERS procedure is flexible as it pro⁃vides a template for sample preparation. The sol⁃vent and sorbent can be optimized according tothe property of the target analytes. Mostly, the or⁃ganic solvent used for extraction and partitioningis acetonitrile, which can easily generate phaseseparation with the addition of sodium chloride.In this work, the volume of extraction solvent andthe kind of adsorption sorbent were systematicallyoptimized to obtain best recovery and sensitivity.2.2.1 Optimization of extraction and partitioningThe volume of extraction solvent in QuEChERSprocedure directly affects the sensitivity and re⁃covery. The insufficient solvent would cause in⁃complete extraction, resulting in poor recovery,while excessive extraction solvent severely dilutesthe analytes, leading to low detection sensitivity.To balance the recovery and sensitivity, thevolume of acetonitrile for extraction was opti⁃mized from 2 mL to 7 mL. As shown in Fig. 3, thepeak areas of four dyes increased from 2 mL to 3mL, and then slightly decreased from 3 mL to 7mL. The results indicated that 3 mL of acetonitrilewas optimal for the extraction of dyes in 2 g ofhomogenized fish tissue. More acetonitrile couldnot improve the extraction efficiency but reducethe detection sensitivity due to the dilution of ana⁃lytes. Thus the volume of extraction solvent wasdetermined to be 3 mL. Then the extraction timewas verified. The homogenized fish tissue ( 2 g)was first extracted by 2 mL of acetonitrile, andthen 1 mL of acetonitrile for re⁃extraction. The su⁃pernatants were merged and detected. The resultsshowed no obvious differences ( results notshown). So the fish tissue was extracted oncewith 3 mL of acetonitrile.Fig. 3 Influence of extraction volume on the peakareas of dyes

中等职业学校是中专吗

中等职业学校是中专吗

2.2.2 Selectivity of adsorption sorbentAfter the extraction/ partitioning, dyes and somenon⁃polar interferences were partitioned into theacetonitrile layer. In order to remove the interfer⁃ences and clean⁃up the sample, d⁃SPE with aproper adsorptive material was performed. C18 andPSA ( structures shown in Fig. 4) are commonlyused materials for adsorption [30,31]. C18 mainlyadsorbs fat, lipid and some other non⁃polar inter⁃ferences, while PSA adsorbs fatty acids and organ⁃ic acids, etc. In this experiment, C18 and PSAwere first employed as adsorbents. As shown inTable 1, the recoveries of dyes were about 70% -90% with C18 as d⁃SPE material. If PSA was usedtogether with C18, the recoveries reduced to about40%- 80%. The color of the sorbents after d⁃SPE·422·第 4 期

ZHU Chengyun, et al: Fast analysis of malachite green, leucomalachite green, crystalviolet and leucocrystal violet in fish tissue based on a modified QuEChERS procedurewas shown in Fig. 5. In Fig. 5a (C18 material) and

Fig. 5b ( C18 and PSA materials ), the sorbentswere obviously changed to blue or violet, furtherdemonstrating the adsorption of MG and CV. Asthe four dyes were all hydrophobic and basic com⁃pounds, the electrostatic attraction between dyesand silanol groups on C18 material together withthe original hydrophobic interaction led to low re⁃coveries. When PSA was added, the alkaline PSAenhanced the ionization of silanols both on C18and PSA, resulting in poor recoveries.Fig. 4 Structures of C18, PSA and C18SAX materialsFig. 5 Color of adsorbents in lower layers afterd⁃SPE procedure

a. C18; b. C18 and PSA; c. C18SAX.

Table 1 Recoveries of the four dyes after d⁃SPE withdifferent adsorbentsAdsorbent

Recoveries / %MG CV LCV LMGC18 (50.0 mg) 86.8 84.8 73.6 87.7

C18 (50.0 mg) and PSA (50.0 mg) 46.0 40.6 78.0 83.7C18SAX (50.0 mg) 101.4 102.2 83.5 87.6In a previous work [ 26], we developed a reversed phase/stronganionexchangemixedmodestationaryphase (name dc18 sax, Fig. 4 ) basedonpolarcopolymerizedapproach.the c 18 saxmaterialpossessesc 18 andquaternaryammoniumgroups, whichcanprovidehydrophobicandelectrostaticinteractionsimultaneously.withc 18 saxasdspematerial、 thenonpolarandacidicinterferencesintheacetonitrilelayereadsorbedbythesorbent.meanwhile, thequaternaryammoniumgroupprovidedelectrostaticrepulsioninteractionagainstthebasicdyes.asshownintable1and fig.5c、 therecoverieswereintherangeof 8351 %-10219 % forthefourdyes, andthec 18 saxmaterialwasstillwhiteaftertheadsorption.con sequention c 18 saxmixedmodematerialsuperiortothemechanicalllymixedc 18 ad thesampleandavoidingadsorptionofdyes.ba ample on the above discussions、 thismethodwaseasilystreamlinedinthedeterminationofdyeresiduesinaquaticproducts.asshowninfig.6,particoncernstheextraction while partinvolvesthecleanupofthesamplewithdspematerial,andpartisforHPLCanalysiiiial

theperformanceoftheoptimizedapproachforthedeterminationofmg,CV,lcvandlmgdyeswasvalidatedwithrespecttothelinearity, 恢复交互复制辅助功能(LOD )和限制功能(loq )。

thecalibrationwasperformedwiththeuseofmatrixmatchedstandards.asshownintable 2,thefourdyesexpressedgooodlinearitiesintherangestheranged withcorrelationcoefficientsallabove 0998.inthespikedrangefrom 5to 25 mg/L,therecoverieswerebetween 8863 % and 11062 %,within

sionsof07%-35%and16%-54%,respectively.the lods (calculatedbysignaltonoiseratiof3 ) were3(2g/kgformg,1-9g 34g/kgforlcvand 241g/kgforlmg.andtheloqs (calculatedbysignaltonoiseratiof 10 ) were10(g/kgformg,6 3 g/kg for CV 70g/kgforlcvand803g/kgforlmg.theresultsindicatedthecapabilityandapplicabilityoftheoptimizedquechersmethodforthepretreeeter mentanddetectionofdyesiofdyesion ofdyedetermination:extraction/partitioning (cleanupbydispersivesolidphaseextractionmaterial (partii ) andHPLCanalysis )

table2matrixmatchedcalibrationsandvalidationdataforfishtissueanalytelinearrange/(mg/l )

correlationcoefficientspiked/(mg/l ) Recovery /%RSD/%

intraday(n=5) inter day (n=15 )敏感性LOD /

(g/kg ) loq/(g/kg ) )。

mg 0.5-100.0.999588.61.72.33.29.61097.91.72.8251031.51.6

cv 0.5-100.0.9995960.72.1.1.95.710105.41.2.325110.60.81.8

lcv 0.5-100.0.998595.81.4.223.470.21096.31.61.925101.234.2

lmg 0.5-100.0.999594.13.53.124.172.31092.80.73.125110.73.5.42.4 sample analysis

theoptimizedmethodwasappliedtodetectmg,CV,lcvandlmginfishsampleswhichwereboughtfromlocalsupermarket.theresultsoftwobatchobatchobatchobatched

thepresentstudydemonstratedthesimplicityandhighefficiencyofquecherspretreatmenthodcombinedwithplcforthefastanalysisoftriphip xchargec 18 wasappliedintheseparationofmg,LMG, cvandlcvwithgoodselectivityandpeakshape.the extraction/partitioninganddspeprocedureinquechersweresystematicallyinvestigated mixedmodeadsorbentwasemployedinthedspeprocedure, exhibitingbetterrecoverythanconventionaladsorbents.methodvalidationdatashowedsatisfactoryrecoveriesandprecisions.ontheontheontheontheotheotheontheothed

ZHU Chengyun,et al:fastanalysisofmalachitegreen,leucomalachite green, crystalvioletandleucocrystalvioletinfishtissuebasedonamodifiedquechersprocedurepresentmethodalsoexists.thedectionsensitivition inimumrequiredperformancelimit (mrpl ) for the dyes. Infuture work,msdetectorwillbeappliedfortheimprovement

[1] Arroyo D,Ortiz M C,Sarabia L A,et al. J Chromatogr A,2009,1216 (29 ) 5472[2] Zhang Z,Zhou K,Bu Y Q,et al.anaaal.j chromanall et al. Food Addit Contam,2012,29 )4) 602[4] Andersen W C,Turnipseeed et al. AnalChim Acta,2009,637 (1/2) 279 [5]

[6] Chen G Y,Miao S. J Agric Food Chem,2010,58 (12 ) 7109[7] Tarbin J A,Chan D,Stubbings G,et al. Anal Chim Acta,2009

[12] Shen Y D,Deng X F,Xu Z L,et al. Anal Chim Acta,2011,707 (1/2) 148 ) Xingw,He L,Yang H,etal.jscifood 89(13 ) et al. Malar J,2011,10:195 [ 15 ] Deng JC,Li L H,Yang X Q,etal.Fal 33(14 ) 150[16] Stubbings G,Tarbin J,Cooper A

[17] Lian Z R,Wang J T. Mar Pollut Bull,2012,64 (12 ) 2656[18] Li Y H,Yang T,Qi X L,et al. Anal Chim Acta,2008,624 lid et al.journalofhenanagriculturalsciences,2011,40 (2) 111[20] Paya P,Anastassiades M,Mack D,et al.analbies 389 (可选) et al.chinesejournalofchromatography,2012,30 (1) 91 )黄YC et al.chinesejournalofchromatography,2013,31 (7) 616 et al.chinesejournalofchromatoor 31 (11 ) 1116 ) 24 ) AguileraLuizm,Vidal J L M,RomeroGonzalez R,et al.J Chromatogr A,2008

[26] Wei J,Guo Z M,Zhang P J,et al. J Chromatogr A,2012,1246:129 [ 27 ] stellac,Rudaz S,Veuthey J L,et al.j chromatom

[ 29 ]张j c,Wei J,zhm,et al.chinesejournalofchromatography,2013,31 (1):79(30 ) Lehotaysj,Son K A,kwon

随机看看

NEW ARTICLE

标签

Tag