第36卷第12期日用化學(xué)品科學(xué)Vol 36 No 122013年12月deterGent cosmeticsDec.2013自而頂空氣相色譜法測(cè)定液體餐具洗滌劑中的甲醇王祿,孫海新,吳海霞(大連市產(chǎn)品質(zhì)量監(jiān)督檢驗(yàn)所,國(guó)家日化產(chǎn)品質(zhì)量監(jiān)督檢驗(yàn)中心,遼寧大連116021摘要:建立了液體餐具洗滌劑中甲醇含量的自動(dòng)頂空氣相色譜測(cè)定方法。采用頂空自動(dòng)進(jìn)樣,DB-FFAP色譜柱分離,火焰離子化檢測(cè)器(FID)檢測(cè),外標(biāo)法定量。結(jié)果表明,甲醇與乙醇等雜質(zhì)有效分離,在10mg/L~1000mg/L濃度范圍內(nèi),所得回歸方程呈良好的線性關(guān)系,r=0.9998,方法檢出限為0.5mg/L,對(duì)黏度較大的樣品,降低稱樣量可使回收率控制在100%-101%,相對(duì)標(biāo)準(zhǔn)偏差(RSD)為0.8%-1.7%。該方法樣品前處理簡(jiǎn)單,分離效果好,基本適用于所有的液體餐具洗滌劑樣品,包括含異丙醇樣品的檢測(cè)。關(guān)鍵詞:餐具洗滌劑;甲醇;頂空;氣相色譜中圖分類號(hào):mQ6496文獻(xiàn)標(biāo)識(shí)碼:A章編號(hào):1006-7264(2013)12-0021-04甲醇是一種有毒易揮發(fā)的工業(yè)原料,可由胃腸毛細(xì)柱法測(cè)定餐具洗滌劑中甲醇含量,但由于液體餐道、呼吸道和皮膚吸收進(jìn)入人體,且在人體內(nèi)有明具洗滌劑通常黏度較大,存在回收率偏高的問(wèn)題。探顯的蓄積作用,過(guò)量的甲醇會(huì)導(dǎo)致失明,或者在體討采用自動(dòng)頂空氣相色譜法測(cè)定液體餐具洗滌劑中的內(nèi)氧化生成甲醛和甲酸而產(chǎn)生致癌作用。國(guó)家標(biāo)準(zhǔn)甲醇含量,并根據(jù)頂空進(jìn)樣理論對(duì)樣品處理方式和頂GB9985-2000規(guī)定手洗餐具用洗滌劑中甲醇含量不空條件以及色譜條件等進(jìn)行分析、優(yōu)化。得超過(guò)1mg/g,甲醇的超標(biāo)通常是由于洗滌劑中使用了含甲醇的工業(yè)乙醇引入的。乙醇具有一定的殺1實(shí)驗(yàn)部分菌、消毒作用,但是工業(yè)乙醇中通常含有一定量的1.1主要儀器與試劑甲醇,因此,手洗餐具洗滌劑生產(chǎn)企業(yè)生產(chǎn)含乙醇Agilent-7890A氣相色譜儀(美國(guó) Agilent公司,的產(chǎn)品時(shí),應(yīng)注意原料乙醇中的甲醇含量,適當(dāng)調(diào)FD檢測(cè)器及化學(xué)工作站)、DB-FFAP色譜柱(60m配乙醇的加入量,否則很容易引起甲醇的超標(biāo)。0.32mm×1.0μm,美國(guó)]&W公司)、 Turbo Matrix HS40GB9985-2000采用直接進(jìn)樣氣相色譜法測(cè)定甲自動(dòng)頂空進(jìn)樣器(美國(guó) Perkin Elmer公司)、22mL頂醇的殘留量,但是液體餐具洗滌劑的黏度大,易于空瓶及配套鋁蓋和橡膠密封墊(美國(guó) Perkin elmer公產(chǎn)生氣泡,對(duì)檢測(cè)結(jié)果產(chǎn)生影響,并且會(huì)降低色譜司)、XS204型電子天平(瑞士 METTLER TOLEDO公儀的進(jìn)樣系統(tǒng)和色譜柱的壽命;另外,GB9985-司)。2000中使用異丙醇作內(nèi)標(biāo),操作繁瑣,也不能用于甲醇(色譜純,天津市科密歐化學(xué)試劑有限公含異丙醇樣品中的甲醇檢測(cè)。自動(dòng)頂空氣相色譜法司)、乙醇(色譜純,天津市科密歐化學(xué)試劑有限公操作簡(jiǎn)單,氣體進(jìn)樣不易引起污染,延長(zhǎng)了色譜柱司)。的使用壽命,并且自動(dòng)進(jìn)樣重復(fù)性好,外標(biāo)法即可1.2色譜條件滿足精度要求,不存在含異丙醇樣品不能檢測(cè)的問(wèn)載氣為高純氮?dú)?流量為1.0 m/min;分流進(jìn)樣,題。張沛玲采用手動(dòng)頂空進(jìn)樣配合玻璃填充色譜柱分流比為10:l;柱溫:初始溫度50℃,保持lmin,測(cè)定餐具洗滌劑中甲醇含量,但存在操作繁瑣,檢以4℃/min升溫至90℃,保持1min,再以20℃/min出限偏高的問(wèn)題;霍任鋒等采用自動(dòng)頂空進(jìn)樣配合升溫至220℃,保持6min;進(jìn)樣口溫度:220℃;中國(guó)煤化工收稿日期:2013-11-04作者簡(jiǎn)介:王祿(1979-),男,河北人,博士CNMHG科技廣塌日用化學(xué)品科學(xué)第36卷FD檢測(cè)器溫度230℃;空氣流量:300 mL/min;氮?dú)饬髁縇.0mL/min的條件下,甲醇和乙醇可以有效氣流量:30ml/min;氫氣流量30mL/min。分離,且峰形較好,見(jiàn)圖1。其余高沸點(diǎn)雜質(zhì)則通過(guò)13頂空進(jìn)樣器條件20℃/min升溫至220℃,保持6min脫除。爐溫:70℃,保溫30min;取樣針:105℃;傳輸線:120℃;載氣壓力:206.85kPa;加壓時(shí)間:3min;進(jìn)樣時(shí)間:0.15min;拔針時(shí)間0.5min;氣相色譜分析循環(huán)時(shí)間:28min甲醇14工作曲線精確稱取色譜純甲醇1g(精確至001mg)于100mL容量瓶中,用二次去離子水稀釋至刻度配置成儲(chǔ)備液,濃度10mg/mL分別移取10μL、100μL、200μL02.557.51012.51517.52022.5300μL、400μL、500μL和1000μL儲(chǔ)備液于10mL容量瓶中,用二次去離子水定容至刻度,得到濃度分別圖1餐具洗滌劑樣品中甲醇頂空氣相色譜圖為10mgL、100mg/L、200mg/L、300mg/L、400mg/Fig 1 Headspace gas chromatogram spectrum of500mg/L和1000mg的甲醇標(biāo)準(zhǔn)使用液。將上述methanol in dishwashing detergents sampl10mL甲醇標(biāo)準(zhǔn)使用液分別置于頂空瓶中,密封22頂空條件優(yōu)化通過(guò)自動(dòng)頂空進(jìn)樣器保溫、進(jìn)樣,得到色譜峰面積頂空平衡溫度的選擇主要根據(jù)溶劑和檢出物的與對(duì)應(yīng)濃度繪制標(biāo)準(zhǔn)曲線沸點(diǎn)來(lái)選擇,既要保證頂空氣體中檢出物有足夠的15樣品處理與測(cè)定精密稱取4g-58(精確至01mg)樣品于頂空濃度,還要低于溶劑的沸點(diǎn),防止頂空瓶漏氣,以中,用二次去離子水稀釋到10mL,密封,旋渦lmin水做溶劑時(shí)通常選擇40℃~80℃為平衡溫度。分別通過(guò)自動(dòng)頂空進(jìn)樣器保溫、進(jìn)樣,根據(jù)標(biāo)準(zhǔn)曲線用試驗(yàn)了60℃、70℃和80℃3個(gè)平衡溫度對(duì)甲醇檢測(cè)得到的色譜峰面積計(jì)算得到相應(yīng)的溶液濃度。實(shí)驗(yàn)的影響,結(jié)果見(jiàn)表1。在其他條件相同的情況下,提高平衡溫度,峰面積分別提高了19.7%和2結(jié)果與討論315%,根據(jù)甲醇的沸點(diǎn)為645℃、溶劑水的沸點(diǎn)為21色譜條件優(yōu)化100℃,綜合考慮上述影響,本文選擇70℃為頂空平甲醇的極性較強(qiáng),根據(jù)“相似相容”原理,通衡溫度。常選擇涂有聚乙二醇或相似固定相的極性毛細(xì)管柱表1頂空平衡溫度對(duì)峰面積的影響如HP- INNOWAX和DB-FFAP毛細(xì)管柱等,DB- FFAP Tab. I Effect of head space equilibration temperature on屬于改性聚乙二醇毛細(xì)管柱,具有更好的耐水性the peak area因此選擇DB-FFAP毛細(xì)管柱。甲醇通常與乙醇在餐平衡溫度/℃具洗滌劑中共存,因甲醇與乙醇的性質(zhì)相近,在色峰面積/pAs63.8譜上的出峰順序也很近,為使甲醇和乙醇及其他雜質(zhì)有效分離,選擇60m長(zhǎng)柱,提高甲醇分離度并改注:甲醇質(zhì)量濃度為300mg/L善峰形。以水做溶劑時(shí),文獻(xiàn)推薦平衡時(shí)間為20min頂空進(jìn)樣相對(duì)于直接進(jìn)樣,進(jìn)樣時(shí)間一般較長(zhǎng),30min,采用200mg/L的甲醇溶液,分別于頂空為降低峰拖尾,通常采用分流進(jìn)樣,在保證檢出限70℃平衡5min~40min,探討頂空平衡時(shí)間對(duì)色譜峰的前提下,為較好的改善峰形,通過(guò)實(shí)驗(yàn)確定分流面積的影響,結(jié)果見(jiàn)圖2。由圖2可見(jiàn),保溫20mn比為10:1。時(shí),氣液兩相基本達(dá)到了平衡。自動(dòng)頂空進(jìn)樣器具甲醇的沸點(diǎn)為645℃,氣相色譜柱溫的選擇通有重疊進(jìn)樣功能,因此選擇較長(zhǎng)的平衡時(shí)間僅對(duì)首常要比檢出物的沸點(diǎn)低10℃左右,因此,通過(guò)實(shí)驗(yàn)次進(jìn)樣的分析時(shí)間影響較大,所以選擇30min的平確定初始柱溫為50℃,保持1min,采用4℃/min升衡時(shí)間,以使氣液兩相更好的達(dá)到平衡溫至90℃,在保證甲醇與乙醇等其他雜質(zhì)有效分離進(jìn)樣時(shí)中國(guó)煤化工及檢出限影響,的前提下,使甲醇快速流出,提高分析效率。在載選擇9s,判CNMH③要求進(jìn)行選擇。第12期王孫質(zhì)自動(dòng)氣相色請(qǐng)法測(cè)定體餐具冼落中的甲技廣于頂空進(jìn)樣是以氣體直接進(jìn)樣,受其他因素影響小,503進(jìn)樣體積準(zhǔn)確,且自動(dòng)頂空進(jìn)樣器進(jìn)樣重復(fù)性好,所以可以不用內(nèi)標(biāo)校正,直接用外標(biāo)法即可得到良好的線性關(guān)系,既節(jié)省了樣品前處理時(shí)間,也節(jié)約了內(nèi)標(biāo)的費(fèi)用24檢出限在優(yōu)化的色譜條件下,根據(jù)線性回歸方程,以3倍的基線噪聲估算,方法的最低檢出濃度為05mg按5g樣品的取樣量稀釋定容至10mL計(jì)算,定性檢平衡時(shí)間7/min出限為1μgg;方法的定量檢出濃度以10倍的基線圖2色譜峰面積與頂空平衡時(shí)間的關(guān)系曲線噪聲估算為17mg,定量檢出限同樣按5g樣品的Fig2 Relationship between peak area and headspace取樣量稀釋定容至10mL,計(jì)算為4μg/g2.5方法精密度與回收率equilibration time本文分別取4g、5g和10g經(jīng)檢測(cè)不含甲醇的液23工作曲線與線性范圍體餐具洗滌劑樣品,加入200μL甲醇儲(chǔ)備液,用二甲醇質(zhì)量濃度在10mg/L~1000mg/L的范圍次去離子水稀釋定容至10mL,密封,旋渦lmin,內(nèi)與色譜峰面積呈良好的線性關(guān)系,線性回歸方程每個(gè)質(zhì)量的樣品制備6個(gè)平行樣,檢測(cè)稱樣量對(duì)回收為y=0.209545x+0.818898,相關(guān)系數(shù)r=0998由率的影響,結(jié)果見(jiàn)表2。表2不同稱樣量與不同加標(biāo)量條件下方法精密度和加標(biāo)回收率結(jié)果Tab 2 Results of method precision and recovery in different weights of sample and amounts of standard addition稱樣量/g加標(biāo)量/μL質(zhì)量分?jǐn)?shù)/%測(cè)定值(x±s)RSD/%回收率/%0.0200.2360±0.0040l182000.0400.4215±0.00461.10.0500.5008±000410.80.0250.2523±000281.l0.1251.2489±0.01120.9表2結(jié)果表明,樣品稱樣量越大,稀釋倍數(shù)越表明回收率在100%~101%,RSD值在0.8~1.1。小,回收率越偏高。這是由于液體餐具洗滌劑通常具與GB9985-2000標(biāo)準(zhǔn)方法比較,實(shí)驗(yàn)結(jié)果無(wú)明顯有較高的黏度,因此使溶質(zhì)甲醇的氣液平衡常數(shù)K差異,驗(yàn)證了方法的適用性較好值偏低,根據(jù)頂空氣液平衡方程3結(jié)論A∝cc=K+B采用自動(dòng)頂空氣相色譜法測(cè)定了液體餐具洗滌劑K值越低,得到的樣品峰面積和質(zhì)量濃度會(huì)越中的甲醇含量,并對(duì)頂空條件和色譜條件等方法參數(shù)高,影響了檢測(cè)結(jié)果的準(zhǔn)確性。當(dāng)取樣量為4g時(shí),進(jìn)行了討論和優(yōu)化,采用4g~5g的稱樣量稀釋的方回收率基本為100%,所以需要綜合考慮樣品的黏度法解決回收率偏高問(wèn)題。與國(guó)家標(biāo)準(zhǔn)方法相比,本方和樣品中甲醇質(zhì)量濃度的影響,當(dāng)樣品黏度較大時(shí)選法樣品前處理簡(jiǎn)單,分離效果好,基本適用于所有的擇4g的稱樣量或者更少,反之,樣品的黏度較小時(shí)液體餐具洗滌劑樣品,包含異內(nèi)醇樣品的檢測(cè)。選擇5g的稱樣量或者更大,普適的稱樣量應(yīng)該是48-參考文獻(xiàn)5g,稀釋測(cè)定,以更好的得到準(zhǔn)確結(jié)果。]張沛玲.頂空氣相色譜法測(cè)定餐具洗滌劑中甲醇!江蘇預(yù)防醫(yī)學(xué),1996(2):34-35另外,稱取4g樣品,分別加入100μL和500μL2霍任鋒韓仰堂盧曉蕊等餐具洗滌劑中甲醇的自動(dòng)頂空甲醇儲(chǔ)備液,按照上述方法分別制備6個(gè)平行樣,測(cè)氣相色譜測(cè)中國(guó)煤化工.27(8:720-721定方法精密度和回收率,結(jié)果同樣列于表2中。結(jié)果CNMHG(下轉(zhuǎn)第42頁(yè))日用化學(xué)品科學(xué)第36卷Multiple viewpoints on improvement of product quality andsupervision level of cosmetic categoryLI Xiao-minDept. of Linjiang, Hangzhou Vocational and Technical College, Hangzhou, Zhejiang 310018, ChinaAbstract: On one hand, it analyzed current status of China cosmetic industry and some posing problems such as too many managementdepartments, low level of access threshold, lack of detection method and so on. On the other hand, actions have been taken to improve the overalllevel of cosmetic industry through different aspects such as the whole supervision throughout the production process, improvement of detectioncapability by multi cooperation, setting up the safety assessment methods and risk evaluation system as well as the enterprise self-disciplineKey words: cosmetic; supervision; self-discipline; sensitivity(上接第23頁(yè))[3]B Kolb, C Welter, C Bichler. Determination of partition coefficients [4] Bruno K, Leslie S E. Static headspace gas chromatography: theoryby automatic equilibrium headspace gas chromatography by vaporand practice[M]. Second Edition. New Jersy: John Wily Sons,hase calibration[]. Chromatographia, 1992, 34 (5-8): 235-240Inc,2006:23,6970.Determination of methanol in liquid dishwashing detergentsby headspace gas chromatographyWANG Lu, SUN Hai-xin, wU HaiDalian Institute of Product Quality Supervision and Inspection, National Supervision andInspection Center for Daily Chemical Product Quality, Dalian, Liaoning 116021, ChinaAbstract: The method for determination of methanol in liquid dishwashing detergents by headspace gas chromatography was establishedThe methanol from dishwashing detergents was separated through an DB-FFAP capillary column and detected by FID after injection byheadspace equipment, and quantification was done by external standard method. Results showed that methanol was well separated fromethanol and other impurities, the linear relation between methanol concentration and the peak area was excellent (=0.999 8)within therange of 10 mg/L -1 000 mg/L, the limit of detection was 0.5 mg/L, the rates of recovery were controlled between 100% to 101%by reducingthe sample size for samples with high viscosity, and the relative standard deviations were 0.8%-1.7%. The method has characteristic of simplepre-treatment and good separation. The method can be applied to almost all of the liquid dishwashing detergents, ineluding the samplecontaining isopropaneKey words: dishwashing detergents; methanol; headspace; gas chromatograph(上接第35頁(yè))劑的刺激性門日用化學(xué)工業(yè),2002,32(5):59-61[9]M. J. Schwinger, Kolloid-Z. Z. Poly[M). USA: US&TO, 1969, 233, [1 1]Namita Deo, Steffen Jockusch, Nicholas J. Turro, et al. SurfactantInteractions with Zein Protein J]. Langmuir, 2003, 19: 5083-0]董銀卯,斯曉帆,彭金亂.用玉米醇溶蛋白測(cè)試表面活性5088Study on the irritation of shampoo by zein testOU Ze-liang, WANG Tan, JIA Ze-bao, WANG Fan, HOU Rui-ruiBeiersdorf Hair Care R& D, Wuhan, Hubei 430056, ChinaAbstract: To investigate the irritation of shampoo caused by surfactants, zein test method was used to test the irritations of both shampoo andshampoo surfactant system separately. The results of imitation generated by surfactant were the same as that in literature. The irritations of marketavailable shampoo and shower 2 in 1 product for children were significantly lower thaneyH中國(guó)煤化工indicated that zein testmethod can be used as a convenient non-animal test method in the surfactant screeningCNMHGtion of irritationKey words: shampoo; imitation; zein; surfactant