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乙酸落叶松脂酯对照品

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  • 基于液质联用仪(LC-MS/MS)测定农作物中松柏醇、松脂醇、落叶松脂素

    基于液质联用仪(LC-MS/MS)测定农作物中松柏醇、松脂醇、落叶松脂素

    [align=center][font='times new roman'][size=20px]基于[url=https://insevent.instrument.com.cn/t/Yp][color=#3333ff]液质[/color][/url]联[/size][/font][font='times new roman'][size=20px]用仪[/size][/font][font='times new roman'][size=20px]([url=https://insevent.instrument.com.cn/t/Yp][color=#3333ff]LC-MS[/color][/url]/MS)[/size][/font][font='times new roman'][size=20px]测定农作物中[/size][/font][font='times new roman'][size=20px]松柏醇、松脂醇、落叶松脂素[/size][/font][/align][align=center][font='times new roman']仪莹[/font][font='times new roman'][sup][size=13px]12[/size][/sup][/font][font='times new roman'],[/font][font='times new roman']孙莹璐[/font][font='times new roman'][sup][size=13px]12[/size][/sup][/font][font='times new roman'],[/font][font='times new roman']张丽娜[/font][font='times new roman'][sup][size=13px]12[/size][/sup][/font][/align][align=center][font='times new roman'](1.[/font][font='times new roman']中国农业科学院[/font][font='times new roman'] [/font][font='times new roman']作物科学研究所[/font][font='times new roman'] [/font][font='times new roman']重大平台中心,北京[/font][font='times new roman'] 100089[/font][font='times new roman'];[/font][font='times new roman']2.[/font][font='times new roman']中国仪器仪表学会科学仪器设备验证评价中心(生命科学站),北京[/font][font='times new roman'] 100089)[/font][/align][font='times new roman']摘要[/font][font='times new roman']: [/font][font='times new roman']用超高效[url=https://insevent.instrument.com.cn/t/5p][color=#3333ff]液相色谱[/color][/url][/font][font='times new roman']-[/font][font='times new roman']串联三重四[/font][font='times new roman']极[/font][font='times new roman']杆质谱法[/font][font='times new roman'](UP[url=https://insevent.instrument.com.cn/t/Yp][color=#3333ff]LC-MS[/color][/url]/MS)[/font][font='times new roman']检测农作物中的[/font][font='times new roman']松柏醇([/font][font='times new roman']CA[/font][font='times new roman'])[/font][font='times new roman']、[/font][font='times new roman']松脂醇([/font][font='times new roman']Pin[/font][font='times new roman'])、落叶松脂素([/font][font='times new roman']Lar[/font][font='times new roman'])[/font][font='times new roman'],色谱柱为[/font][font='times new roman']Agilent SB C18 RRHD[/font][font='times new roman'],[/font][font='times new roman']检测柱温为[/font][font='times new roman']40[/font][font='times new roman']℃[/font][font='times new roman'],[/font][font='times new roman']初始[/font][font='times new roman']流动相为乙腈[/font][font='times new roman']∶[/font][font='times new roman']水[/font][font='times new roman']=4[/font][font='times new roman']∶[/font][font='times new roman']1[/font][font='times new roman'],按[/font][font='times new roman']5mM[/font][font='times new roman']的量加乙酸铵,检测流速为[/font][font='times new roman']0.3mL/min[/font][font='times new roman'],其检出限分别为[/font][font='times new roman']1.25~ 5. 10 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman'],定量[/font][font='times new roman']限分别[/font][font='times new roman']为[/font][font='times new roman']3. 75~ 15. 60 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman'],满足农作物中[/font][font='times new roman']CA[/font][font='times new roman']、[/font][font='times new roman']Pin[/font][font='times new roman']和[/font][font='times new roman']Lar[/font][font='times new roman']同时检测的要求。[/font][align=left][font='times new roman']关键词:[/font][font='times new roman']超高效[url=https://insevent.instrument.com.cn/t/5p][color=#3333ff]液相色谱[/color][/url][/font][font='times new roman']-[/font][font='times new roman']串联质谱;[/font][font='times new roman']松柏醇[/font][font='times new roman'];[/font][font='times new roman']松脂醇[/font][font='times new roman'];[/font][font='times new roman']落叶松脂素;[/font][font='times new roman']农作物[/font][/align][align=center][font='times new roman'][size=18px][color=#666666]Determination of [/color][/size][/font][font='times new roman'][size=18px][color=#666666]CA[/color][/size][/font][font='times new roman'][size=18px][color=#666666], [/color][/size][/font][font='times new roman'][size=18px][color=#666666]Pin [/color][/size][/font][font='times new roman'][size=18px][color=#666666]and[/color][/size][/font][font='times new roman'][size=18px][color=#666666] Lar[/color][/size][/font][font='times new roman'][size=18px][color=#666666] in crops based on [url=https://insevent.instrument.com.cn/t/Yp][color=#3333ff]LC-MS[/color][/url]/MS[/color][/size][/font][/align][align=center][font='times new roman']Y[/font][font='times new roman']i[/font][font='times new roman'] Ying[/font][font='times new roman'][sup][size=13px]12[/size][/sup][/font][font='times new roman'] ,[/font][font='times new roman'][sup][size=13px] [/size][/sup][/font][font='times new roman']S[/font][font='times new roman']un[/font][font='times new roman'] Yinglu[/font][font='times new roman'][sup][size=13px]12[/size][/sup][/font][font='times new roman'],[/font][font='times new roman']Z[/font][font='times new roman']hang[/font][font='times new roman'] Lina[/font][font='times new roman'][sup][size=13px]12[/size][/sup][/font][/align][align=center][font='times new roman'][size=12px]([/size][/font][font='times new roman'][size=12px]1.Major[/size][/font][font='times new roman'][size=12px] Platform Center, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100089, China 2. Scientific Instruments and Equipment Verification and Evaluation Center of China Instruments and Apparatus Society (Bioscience Station))[/size][/font][/align][font='times new roman']Abstract[/font][font='times new roman']:[/font][font='times new roman']Ultra-performance liquid chromatography-tandem triple quadrupole mass spectrometry (UP[url=https://insevent.instrument.com.cn/t/Yp][color=#3333ff]LC-MS[/color][/url]/MS) was used to detect [/font][font='times new roman']CA, Pin[/font][font='times new roman'] and [/font][font='times new roman']Lar[/font][font='times new roman'] in crops. The chromatographic column was Waters [/font][font='times new roman']Acquity[/font][font='times new roman'] [/font][font='times new roman']Agilent SB C18 RRHD[/font][font='times new roman'], the temperature of the detection column was [/font][font='times new roman']40[/font][font='times new roman']℃, the mobile phase consisted of [/font][font='times new roman']acetonitrile[/font][font='times new roman']:[/font][font='times new roman']water[/font][font='times new roman'] =4[/font][font='times new roman']:[/font][font='times new roman']1, and [/font][font='times new roman']5mM[/font][font='times new roman'] ammonium acetate was added. The detection [/font][font='times new roman']flow [/font][font='times new roman']rate was 0.3[/font][font='times new roman'] [/font][font='times new roman']mL/min, the detection limit[/font][font='times new roman']s[/font][font='times new roman'] w[/font][font='times new roman']ere[/font][font='times new roman'] 1.25-5.10 [/font][font='times new roman']μg[/font][font='times new roman']/L, [/font][font='times new roman']and [/font][font='times new roman']the quantification limit[/font][font='times new roman']s[/font][font='times new roman'] w[/font][font='times new roman']ere[/font][font='times new roman'] 3.75-15.60 [/font][font='times new roman']μg[/font][font='times new roman']/L, respectively[/font][font='times new roman'],[/font][font='times new roman'] [/font][font='times new roman']which satisfied t[/font][font='times new roman']he requirements [/font][font='times new roman']of[/font][font='times new roman'] simultaneous detection of T6P and Tre in crops.[/font][align=left][font='times new roman']Keywords:[/font][font='times new roman'] U[/font][font='times new roman']PLC[/font][font='times new roman']-MS/MS [/font][font='times new roman']CA[/font][font='times new roman'] [/font][font='times new roman']Pin[/font][font='times new roman'] [/font][font='times new roman']Lar [/font][font='times new roman']crops [/font][/align][font='times new roman'][size=18px]1 [/size][/font][font='times new roman'][size=18px]引言[/size][/font][font='times new roman']自[/font][font='times new roman']1997[/font][font='times new roman']年[/font][font='times new roman']Lewis[/font][font='times new roman']等首次提出[/font][font='times new roman']DIR[/font][font='times new roman']蛋白广泛存在于植物体内,参与并[/font][font='times new roman']指导木脂素[/font][font='times new roman']生物合成过程中位置的选择和立体选择,这类具有[/font][font='times new roman']dirigent[/font][font='times new roman']结构域的蛋白就引起了科学家的广泛关[/font][font='times new roman']注。为了[/font][font='times new roman']了解木脂素[/font][font='times new roman']在不同农作物组织中含量的差异,我们通过[/font][font='times new roman']HP[url=https://insevent.instrument.com.cn/t/Yp][color=#3333ff]LC-MS[/color][/url]/MS[/font][font='times new roman']平台[/font][font='times new roman']对木脂素[/font][font='times new roman']代谢途径中的母核化合物[/font][font='times new roman']CA[/font][font='times new roman'],[/font][font='times new roman']Pin[/font][font='times new roman']和[/font][font='times new roman']Lar[/font][font='times new roman']进行含量测定[/font][font='times new roman'][sup][size=13px][1,2][/size][/sup][/font][font='times new roman']。[/font][font='times new roman'][size=18px]2 [/size][/font][font='times new roman'][size=18px]材料和方法[/size][/font][font='times new roman']仪器与试剂:[/font][font='times new roman']谱育[/font][font='times new roman']EXPEC5210[/font][font='times new roman']三[/font][font='times new roman']重四[/font][font='times new roman']极[/font][font='times new roman']杆[url=https://insevent.instrument.com.cn/t/5p][color=#3333ff]液相色谱[/color][/url]联用仪([/font][font='times new roman']UPLC5210[/font][font='times new roman']二[/font][font='times new roman']元高压输液泵、自动进样器、[/font][font='times new roman']柱温箱[/font][font='times new roman']、质谱仪)、电子天平[/font][font='times new roman'](BSA224S[/font][font='times new roman']型,赛多利斯科学仪器有限公司产品[/font][font='times new roman']),KQ-250E[/font][font='times new roman']型超声波清洗器[/font][font='times new roman'] ([/font][font='times new roman']昆山禾创超声[/font][font='times new roman']仪器有限公司产品[/font][font='times new roman'])[/font][font='times new roman'],[/font][font='times new roman']PICO17[/font][font='times new roman']型离心机[/font][font='times new roman']([/font][font='times new roman']美国赛默飞公司产品[/font][font='times new roman'])[/font][font='times new roman']。[/font][align=center][img]https://ng1.17img.cn/bbsfiles/images/2023/10/202310301455540531_1340_5708872_3.jpeg[/img][/align][font='times new roman']乙腈[/font][font='times new roman']([/font][font='times new roman']色谱纯[/font][font='times new roman'],[/font][font='times new roman']美国赛默飞公司产品[/font][font='times new roman'])[/font][font='times new roman'],乙酸铵[/font][font='times new roman']([/font][font='times new roman']纯度[/font][font='times new roman']≥98[/font][font='times new roman']%,德国[/font][font='times new roman']CNW [/font][font='times new roman']公司产品[/font][font='times new roman'])[/font][font='times new roman']。[/font][font='times new roman'] T6P[/font][font='times new roman']和[/font][font='times new roman']Tre[/font][font='times new roman']购[/font][font='times new roman']sigma-[/font][font='times new roman']aldrich[/font][font='times new roman']贸易有限公司,质谱用水为屈臣氏蒸馏水。[/font][font='times new roman']分析条件:色谱柱[/font][font='times new roman']:Agilent SB C18 RRHD Column (100 mm×2.1 mm,1.8 [/font][font='times new roman']μm[/font][font='times new roman'])[/font][font='times new roman'],[/font][font='times new roman']柱温[/font][font='times new roman']40 ℃[/font][font='times new roman'],进样体积[/font][font='times new roman']5 [/font][font='times new roman']μl[/font][font='times new roman'],流动相[/font][font='times new roman']:A:[/font][font='times new roman']乙腈[/font][font='times new roman'] B:5 mM[/font][font='times new roman']乙酸铵[/font][font='times new roman']-[/font][font='times new roman']水,流速[/font][font='times new roman']0.3ml/min[/font][align=center][font='times new roman'][color=#666666]0min [/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666] 20A%[/color][/font][/align][align=center][font='times new roman'][color=#666666]1 [/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666] 20A%[/color][/font][/align][align=center][font='times new roman'][color=#666666]5 [/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666] 80A%[/color][/font][/align][align=center][font='times new roman'][color=#666666]5.1 [/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666]20A%[/color][/font][/align][align=center][font='times new roman'][color=#666666]7 [/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666] 20A%[/color][/font][/align][font='times new roman']离子源[/font][font='times new roman']:[/font][font='times new roman']电喷雾离子源;扫描方式[/font][font='times new roman']:[/font][font='times new roman']负离子切换扫描;检测方式:质谱多反应监测[/font][font='times new roman'](MRM)[/font][font='times new roman'][sup][size=13px] [3][/size][/sup][/font][font='times new roman'];优化的质谱条件见表[/font][font='times new roman']1[/font][font='times new roman']。[/font][align=center][font='times new roman'][size=12px][color=#666666]表[/color][/size][/font][font='times new roman'][size=12px][color=#666666]1[/color][/size][/font][font='times new roman'][size=12px][color=#666666] [/color][/size][/font][font='times new roman'][size=12px][color=#666666] Lar[/color][/size][/font][font='times new roman'][size=12px][color=#666666]和[/color][/size][/font][font='times new roman'][size=12px][color=#666666]CA[/color][/size][/font][font='times new roman'][size=12px][color=#666666]、[/color][/size][/font][font='times new roman'][size=12px][color=#666666]Pin[/color][/size][/font][font='times new roman'][size=12px][color=#666666]的质谱多反应检测质谱参数[/color][/size][/font][/align][table][tr][td][font='times new roman'][color=#666666]化合物[/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666]母离子([/color][/font][font='times new roman'][color=#666666]m/z) [/color][/font][font='times new roman'][color=#666666]子离子([/color][/font][font='times new roman'][color=#666666]m/z) [/color][/font][font='times new roman'][color=#666666]锥孔电压[/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666]碰撞能[/color][/font][font='times new roman'][color=#666666] [/color][/font][/td][/tr][tr][td][font='times new roman'][color=#666666]Lar [/color][/font][font='times new roman'] 359 329.1 50 [/font][font='times new roman'] [/font][font='times new roman'] 10[/font][/td][/tr][tr][td][font='times new roman'][color=#666666]CA [/color][/font][font='times new roman'][sub][size=13px] [/size][/sub][/font][font='times new roman'] 179.2 146[/font][font='times new roman']、[/font][font='times new roman']164 [/font][font='times new roman'] [/font][font='times new roman'] 50 [/font][font='times new roman'] [/font][font='times new roman'] 15[/font][/td][/tr][tr][td][font='times new roman'][color=#666666]Pin 357 151[/color][/font][font='times new roman'][color=#666666]、[/color][/font][font='times new roman'][color=#666666]136.1 50 [/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666] 20[/color][/font][/td][/tr][/table][font='times new roman'][size=18px]3 [/size][/font][font='times new roman'][size=18px]结果与分析[/size][/font][font='times new roman'][size=16px]3.1[/size][/font][font='times new roman'][size=16px]线性范围与检出限[/size][/font][font='times new roman']Agilent SB C18 RRHD[/font][font='times new roman']色谱柱检测时,[/font][font='times new roman']Lar[/font][font='times new roman']的质量浓度为[/font][font='times new roman']7.25 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']14.5 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']72.5 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']145 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']290 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']725 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']1450 [/font][font='times new roman']μg[/font][font='times new roman']/L, CA[/font][font='times new roman']的质量浓度为[/font][font='times new roman']8.65 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']17.3 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']43.25 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']86.5 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']173 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman'] 346 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']865 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']1730 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman'],[/font][font='times new roman']Pin[/font][font='times new roman']的质量浓度为[/font][font='times new roman']8.23 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']16.46 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']82.3 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']164.6 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']329.2 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']823 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman']、[/font][font='times new roman']1646 [/font][font='times new roman']μg[/font][font='times new roman']/L[/font][font='times new roman'];按照优化后的色谱条件对每个点重复测定[/font][font='times new roman']3[/font][font='times new roman']次。以质量浓度为横坐标,以峰面积为纵坐标,绘制标准曲线,以标准曲线的第一个和最后一个点的质量浓度作为线性范围。[/font][font='times new roman']不同浓度梯度的[/font][font='times new roman']Lar[/font][font='times new roman']、[/font][font='times new roman']CA[/font][font='times new roman']和[/font][font='times new roman']Pin[/font][font='times new roman']通过[/font][font='times new roman']C18[/font][font='times new roman']柱时在线性范围内呈现良好的线性关系;系数均在[/font][font='times new roman']0. 99 [/font][font='times new roman']以上,均符合实际分析的要求[/font][font='times new roman'][sup][size=13px][[/size][/sup][/font][font='times new roman'][sup][size=13px]4[/size][/sup][/font][font='times new roman'][sup][size=13px]][/size][/sup][/font][font='times new roman']。[/font][align=center][img]https://ng1.17img.cn/bbsfiles/images/2023/10/202310301455542574_4489_5708872_3.jpg[/img][/align][align=center][font='times new roman'][size=12px][color=#000000]图[/color][/size][/font][font='times new roman'][size=12px][color=#000000]1 [/color][/size][/font][font='times new roman'][size=12px][color=#000000]Lar[/color][/size][/font][font='times new roman'][size=12px][color=#000000]标准曲线[/color][/size][/font][/align][align=center][img]https://ng1.17img.cn/bbsfiles/images/2023/10/202310301455544692_9457_5708872_3.jpg[/img][/align][align=center][font='times new roman'][size=12px][color=#000000]图[/color][/size][/font][font='times new roman'][size=12px][color=#000000]2 [/color][/size][/font][font='times new roman'][size=12px][color=#000000]CA[/color][/size][/font][font='times new roman'][size=12px][color=#000000]标准曲线[/color][/size][/font][/align][align=center][img]https://ng1.17img.cn/bbsfiles/images/2023/10/202310301455545568_5903_5708872_3.jpg[/img][/align][align=center][font='times new roman'][size=12px][color=#000000]图[/color][/size][/font][font='times new roman'][size=12px][color=#000000]3 Pin[/color][/size][/font][font='times new roman'][size=12px][color=#000000]标准曲线[/color][/size][/font][/align][align=center][font='times new roman'][size=12px][color=#000000]表[/color][/size][/font][font='times new roman'][size=12px][color=#000000]2 [/color][/size][/font][font='times new roman'][size=12px][color=#000000] [/color][/size][/font][font='times new roman'][size=12px][color=#000000]Lar[/color][/size][/font][font='times new roman'][size=12px][color=#000000]、[/color][/size][/font][font='times new roman'][size=12px][color=#000000]CA[/color][/size][/font][font='times new roman'][size=12px][color=#000000]和[/color][/size][/font][font='times new roman'][size=12px][color=#000000]Pin[/color][/size][/font][font='times new roman'][size=12px][color=#000000]标准曲线、线性范围、决定系数、检出限和定量限[/color][/size][/font][/align][table][tr][td][font='times new roman'][color=#666666]化合物[/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666]标准曲线方程[/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666]线性范围[/color][/font][font='times new roman'][color=#666666]([/color][/font][font='times new roman'][color=#666666]μg[/color][/font][font='times new roman'][color=#666666]/L) [/color][/font][font='times new roman'][color=#666666]相关系数[/color][/font][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][color=#666666]检出限[/color][/font][font='times new roman'][color=#666666]([/color][/font][font='times new roman'][color=#666666]μg[/color][/font][font='times new roman'][color=#666666]/L) [/color][/font][font='times new roman'][color=#666666]定量限[/color][/font][font='times new roman'][color=#666666]([/color][/font][font='times new roman'][color=#666666]μg[/color][/font][font='times new roman'][color=#666666]/L) [/color][/font][/td][/tr][tr][td][font='times new roman'][color=#666666]Lar y[/color][/font][font='times new roman'][color=#666666]=[/color][/font][font='times new roman'][color=#666666]422.9818x 7.25-1450 0.9996 1.25 3.75[/color][/font][/td][/tr][tr][td][font='times new roman'][color=#666666]CA y[/color][/font][font='times new roman'][color=#666666]=[/color][/font][font='times new roman'][color=#666666]33.6037x 8.65- 1730 0.9996 5.10 15.60[/color][/font][/td][/tr][tr][td][font='times new roman'][color=#666666]Pin y[/color][/font][font='times new roman'][color=#666666]=[/color][/font][font='times new roman'][color=#666666]9433.8945x 8.23- 1646 0.9998 3.59 10.77[/color][/font][/td][/tr][/table][font='times new roman'][size=16px]3.[/size][/font][font='times new roman'][size=16px]2[/size][/font][font='times new roman'][size=16px]实际样品的测定[/size][/font][font='times new roman']用建立的方法测定[/font][font='times new roman']40[/font][font='times new roman']份小麦类样品,部分样品的色谱图如图[/font][font='times new roman']4[/font][font='times new roman']所示。[/font][align=center][img]https://ng1.17img.cn/bbsfiles/images/2023/10/202310301455547572_5306_5708872_3.jpeg[/img][/align][align=center][img]https://ng1.17img.cn/bbsfiles/images/2023/10/202310301455549420_9726_5708872_3.jpeg[/img][font='times new roman'][color=#666666] [/color][/font][font='times new roman'][size=12px][color=#000000]图[/color][/size][/font][font='times new roman'][size=12px][color=#000000]4[/color][/size][/font][font='times new roman'][size=12px][color=#000000] [/color][/size][/font][font='times new roman'][size=12px][color=#000000]小麦叶片中[/color][/size][/font][font='times new roman'][size=12px][color=#000000]Lar[/color][/size][/font][font='times new roman'][size=12px][color=#000000]、[/color][/size][/font][font='times new roman'][size=12px][color=#000000]CA[/color][/size][/font][font='times new roman'][size=12px][color=#000000]和[/color][/size][/font][font='times new roman'][size=12px][color=#000000]Pin[/color][/size][/font][font='times new roman'][size=12px][color=#000000]的色谱图[/color][/size][/font][/align][font='times new roman']且同一批次样品[/font][font='times new roman']3[/font][font='times new roman']次平行[/font][font='times new roman']样得到[/font][font='times new roman']T6P[/font][font='times new roman']和[/font][font='times new roman']Tre[/font][font='times new roman']的[/font][font='times new roman']RSD [/font][font='times new roman']值小于[/font][font='times new roman']3%[/font][font='times new roman'],如表[/font][font='times new roman']3[/font][font='times new roman']所示,说明前处理方法可行,仪器的稳定性良好[/font][font='times new roman'][sup][size=13px][[/size][/sup][/font][font='times new roman'][sup][size=13px]5][/size][/sup][/font][font='times new roman']。[/font][align=center][img]https://ng1.17img.cn/bbsfiles/images/2023/10/202310301455551095_7818_5708872_3.png[/img][/align][align=center][font='times new roman'][size=12px][color=#000000]表[/color][/size][/font][font='times new roman'][size=12px][color=#000000]3[/color][/size][/font][font='times new roman'][size=12px][color=#000000] [/color][/size][/font][font='times new roman'][size=12px][color=#000000]小麦叶片中[/color][/size][/font][font='times new roman'][size=12px][color=#000000]Lar[/color][/size][/font][font='times new roman'][size=12px][color=#000000]、[/color][/size][/font][font='times new roman'][size=12px][color=#000000]CA[/color][/size][/font][font='times new roman'][size=12px][color=#000000]和[/color][/size][/font][font='times new roman'][size=12px][color=#000000]Pin[/color][/size][/font][font='times new roman'][size=12px][color=#000000]的测定值[/color][/size][/font][/align][font='times new roman']分别对小麦[/font][font='times new roman']不同组织的样本[/font][font='times new roman']进行前处理提取实验,前处理方法简便可行,仪器性能可靠,满足对样品中[/font][font='times new roman']松柏醇、松脂醇、落叶松脂素[/font][font='times new roman']的检测。[/font][font='times new roman']参考文献[/font][font='times new roman'][1] [/font][font='times new roman']周海旭[/font][font='times new roman']. [/font][font='times new roman']樟树[/font][font='times new roman']叶中木脂素[/font][font='times new roman']提取分离及其生物活性研究[/font][font='times new roman'][D]. 2017.[/font][font='times new roman'][2] [/font][font='times new roman']戴清源[/font][font='times new roman'],[/font][font='times new roman']朱秀灵[/font][font='times new roman'],[/font][font='times new roman']刘皓[/font][font='times new roman']. [/font][font='times new roman']芝麻木脂素[/font][font='times new roman']及其生物活性研究进展[/font][font='times new roman'][J]. [/font][font='times new roman']农产品加工[/font][font='times new roman'].[/font][font='times new roman']学刊[/font][font='times new roman'], 2012, (1[/font][font='times new roman']期[/font][font='times new roman']):16-21. [/font][font='times new roman'][3] Du, [/font][font='times new roman']Bingyuan[/font][font='times new roman'], et al. [/font][font='times new roman']Phillygenin[/font][font='times new roman'] exhibits anti-inflammatory activity through modulating multiple cellular behaviors of mouse lymphocytes[J]. Immunopharmacology and immunotoxicology, 2019, 41(1): 76-85.[/font][font='times new roman'][4] Murata, Jun, et al. Oxidative rearrangement of (+)-[/font][font='times new roman']sesamin[/font][font='times new roman'] by CYP92B14 co-generates twin dietary lignans in sesame[J]. Nature communications, 2017, 8(1): 1-10.[/font][font='times new roman'][5] Hano, C, et al. [/font][font='times new roman']Pinoresinol-lariciresinol[/font][font='times new roman'] reductase gene expression and [/font][font='times new roman']secoisolariciresinol[/font][font='times new roman'] [/font][font='times new roman']diglucoside[/font][font='times new roman'] accumulation in developing flax (Linum [/font][font='times new roman']usitatissimum[/font][font='times new roman']) seeds[J]. Planta, 2016, 224(6): 1291-1301.[/font]

  • 松脂酸(松香酸)测定方法

    松脂酸(松香酸)测定方法

    [align=center][size=24px][b]松脂酸(松香酸)测定方法[/b][/size][/align] 松香酸用于发酵工业,并且可用作肥皂和造纸工业的填料。松香酸为三环二萜类化合物。在含水乙醇中得单斜片状结晶。熔点172~175℃,旋光度-102°(无水乙醇)。不溶于水,溶于乙醇、苯、氯仿、乙醚、丙酮、二硫化碳以及稀氢氧化钠水溶液。为天然松香树脂的主要成分。本测定方法是建立松香中松脂酸测定,液体原药松脂酸铜中松脂酸测定;文献报道,[url=https://insevent.instrument.com.cn/t/5p][color=#3333ff]液相色谱[/color][/url]法测定松脂酸铜需要加入盐酸,[font=宋体]将松脂酸铜衍生转化为松脂酸,图[/font][font='Times New Roman','serif']1[/font][font=宋体]列出了其可能的转化途径,确定松脂酸铜实际测定对象为松脂酸。厂家送过来的原药是盐酸处理过的所以我们直接检测就行。[/font][align=center][img=,589,168]https://ng1.17img.cn/bbsfiles/images/2023/08/202308150859397658_4592_3963412_3.jpg!w589x168.jpg[/img][/align][align=center][b][font=宋体]图[/font][font='Times New Roman','serif']1 [/font][/b][font=宋体][b]松脂酸铜转化为松脂酸[/b][/font][/align][align=left][b]实验方法[/b][/align][align=left][/align][align=left][font='Times New Roman','serif']1[/font][font=宋体]试剂:乙腈(色谱级),磷酸(分析纯);盐酸分析纯[/font][font=&] [font='Times New Roman','serif']2[/font][font=宋体][url=https://insevent.instrument.com.cn/t/5p][color=#3333ff]液相[/color][/url]条件:[/font][font='Times New Roman','serif']LC-20AT [/font][font=宋体]波长:[/font][font='Times New Roman','serif']245nm [/font][font=宋体];进样量:[/font][font='Times New Roman','serif']5μL[/font][font=宋体]色谱柱型号:[/font][font='Times New Roman','serif']Agilent Eclipse XDB-C18(2.1 mm×100mm, 2.7 μm), [/font][font=宋体]柱温:[/font][font='Times New Roman','serif']30.5 [/font][font=宋体]℃,流动相条件如表[/font][font='Times New Roman','serif']1[/font][font=宋体]:[/font][/font][/align][align=center][font=&][font=宋体]表1 流动相洗脱程序[/font][/font][/align][align=center][font=&][font=宋体][img=,559,298]https://ng1.17img.cn/bbsfiles/images/2023/08/202308151105132742_2164_3963412_3.jpg!w559x298.jpg[/img][/font][/font][/align][align=left][font='Times New Roman','serif']3 [/font][font=宋体]标准品配制:称取一定量的松脂酸,用乙腈[/font][font='Times New Roman','serif']:0.1%[/font][font=宋体]磷酸([/font][font='Times New Roman','serif']V/V=70:30[/font][font=宋体])溶解,定容,得到浓度为[/font][font='Times New Roman','serif']200 μg/mL[/font][font=宋体],待测。[/font][/align][font=宋体][/font][align=center][img=,534,242]https://ng1.17img.cn/bbsfiles/images/2023/08/202308150902130177_1955_3963412_3.jpg!w534x242.jpg[/img]图2 标准品色谱图[/align][align=left][font='Times New Roman','serif']4[/font][font=宋体]样品制备:[/font][/align][align=left][font='Times New Roman','serif']4.1[/font][font=宋体]松香用研钵研碎,称取一定量的样品,用乙腈[/font][font='Times New Roman','serif']:0.1%[/font][font=宋体]磷酸([/font][font='Times New Roman','serif']V/V=70:30[/font][font=宋体])超声溶解,定容至[/font][font='Times New Roman','serif']50 mL[/font][font=宋体],然后过滤待测。[/font][/align][align=center][img=,532,236]https://ng1.17img.cn/bbsfiles/images/2023/08/202308150904090783_7851_3963412_3.jpg!w532x236.jpg[/img][/align][align=center]图3 松香样1色谱图[/align][align=center][/align][align=center][img=,498,227]https://ng1.17img.cn/bbsfiles/images/2023/08/202308150904412965_7172_3963412_3.jpg!w498x227.jpg[/img][/align][align=center]图4 松香样2色谱图[/align][align=left]4.2 称取一定量的液体原药,用乙腈:0.1%磷酸(V/V=70:30)溶解,定容至50mL, 过0.45μm滤膜,待测。[/align][align=center][img=,560,254]https://ng1.17img.cn/bbsfiles/images/2023/08/202308150908303829_927_3963412_3.jpg!w560x254.jpg[/img]图5 原药1色谱图[/align][align=center][img=,513,235]https://ng1.17img.cn/bbsfiles/images/2023/08/202308150908401428_7495_3963412_3.jpg!w513x235.jpg[/img]图6 原药2色谱图[img=,690,516]https://ng1.17img.cn/bbsfiles/images/2023/08/202308150914267479_9450_3963412_3.jpg!w690x516.jpg[/img]图7 松香(1和2)样品图[/align][align=left]结论:从松香质地能看出来松香2 质地要优于松香1,松香1中松香酸含量44.3%,松香2中松香酸含量88.5%,原药1含量12.5%,原药2中含量42.1%。后来联系客户说松香1是湿地松得到的,松香2是马尾松得到的。不同植物得到的松香差异比较明显。[/align][font='Times New Roman','serif'][/font][align=left][font=宋体][/font][/align][align=center][/align][align=left][/align][align=left][/align]

  • 高效液相色谱法测定果蔬中松脂酸铜

    分享一个不常见的农药松脂酸铜的高效[url=https://insevent.instrument.com.cn/t/5p][color=#3333ff]液相色谱[/color][/url]法-紫外检测器检测方法。样品利用盐酸衍生生成松脂酸,通过HPLC-UVD对松脂酸进行定量,间接定量松脂酸铜。结果表明,松脂酸铜的相关系数R2为0.999 6,平均回收率在77% ~ 108%,相对标准偏差均小于5%,线性关系良好,方法的检出限(limit of detection,LOD)为0.03 mg/kg,定量限(limit of quantitation,LOQ )为0.1 mg/kg。该方法简便、准确、快速,可满足果蔬中松脂酸铜残留检测灵敏度和准确度的要求,其他果蔬样品中的松脂酸铜残留也可参照该方法进行分析。 详见王美然等,食品与发酵工业,2022.

  • 果蔬中松脂酸铜残留的液相色谱方法

    基于高效[url=https://insevent.instrument.com.cn/t/5p][color=#3333ff]液相色谱[/color][/url]法-紫外检测器(high-performance liquid chromatography -ultraviolet detector,HPLC-UVD )检测松脂酸铜在火龙果、豇豆和杧果3种果蔬中的农药残留的分析方法。原理为盐酸将松脂酸铜转化为松脂酸,用石油醚超声提取,提取液蒸干后使用乙腈定容,通过HPLC-UVD对样品进行定量测定。结果表明,松脂酸铜的相关系数R2为0.999 6,平均回收率在77% ~ 108%,相对标准偏差均小于5%,线性关系良好,方法的检出限(limit of detection,LOD)为0.03 mg/kg,定量限(limit of quantitation,LOQ )为0.1 mg/kg。该方法简便、准确、快速,可满足果蔬中松脂酸铜残留检测灵敏度和准确度的要求,其他果蔬样品中的松脂酸铜残留也可参照该方法进行分析。详见[font=&][color=#666666]10.13995/j.cnki.11-1802/ts.030912[/color][/font]

  • 砂仁含量乙酸龙脑脂对照品的峰是这样的,什么原因?

    砂仁含量乙酸龙脑脂对照品的峰是这样的,什么原因?

    砂仁含量测定,乙酸龙脑脂对照品的峰是这样的,什么原因?[img=,690,920]https://ng1.17img.cn/bbsfiles/images/2019/09/201909291048233492_354_4008962_3.png[/img][img=,690,920]https://ng1.17img.cn/bbsfiles/images/2019/09/201909291048362627_1375_4008962_3.png[/img][img=,690,920]https://ng1.17img.cn/bbsfiles/images/2019/09/201909291048546892_2814_4008962_3.png[/img]

  • 求助,乙酸乙酯对照问题

    今天做乙酸乙酯残留,对照面积分别是702.2,722.5,738.6,790.4,821.2,rsd为6.5%,第一针和最后一针面积相差120左右,但rsd在10%内,这5个对照能采用吗?

  • 【求助】松脂气相色谱分析求助!

    想对松脂中的树脂酸进行甲酯化,据文献,试剂一般为四甲基氢氧化铵甲醇溶液或三甲基氢氧化硫甲醇溶液,哪位知道哪里有卖这些试剂的么?问了几个代理,都说只卖四甲基氢氧化铵水溶液,要自己除水实在太麻烦了。。。谢谢!

  • 松脂化学组成分析

    松脂化学组成分析

    松脂化学组成分析,用气质做的,峰的分离效果已经优化好,现在定性出现新的问题,45min之后的出峰谱库搜索很多重复,保留时间53.6393、53.7428、53.9045、53.9951、54.0857、54.228、55.4117、55.7093、55.9098、55.9616、56.1944、56.4726、56.589、57.1001、57.9669出来的15个峰谱库搜索均为1-Phenanthrenecarboxylic acid, 1,2,3,4,4a,9,10,10a-octahydro-1,4a-dimethyl-7-(1-methylethyl)-, methyl ester, -。按照理论,应该是各种不同的松香酸(同分异构体)。我们谱库是NIST05,是否需要再安装什么专业库才能解决问题?http://ng1.17img.cn/bbsfiles/images/2011/08/201108290930_312669_1912751_3.jpg

  • 【讨论】关于对照品溶液的制备

    大家经常做气相需要测对照品溶液,有时对照品溶液的出峰面积在不同时期可能差异较大,大家遇到过这样的问题吗?问题:取甲醇、乙酸乙酯、甲苯适量,精密称定,用DMF溶解稀释定容制成每1ml中约含甲醇60ug、乙酸乙酯100ug、甲苯20ug的混合溶液。那么我们实际称取的对照质量应该在什么范围内是可以接受的?因为称量的差异会导致对照品出峰面积的差异。问题:如何能用天平称准对照试剂的量?(有机溶剂甲醇、乙腈、二氯甲烷等)换算成体积量取还是直接称取?

  • 每天三个小分享:阿里红主要化学成分

    阿里红【别名】落叶松茸【化学成份】含多种三萜和甾体化合物,其中主要是齿孔酸和去氢齿孔酸。其他尚分得齿孔醇、齿孔二醇、齿孔醛、硫色多孔菌酸、麦角甾四烯-4,6,8(14),22-酮-3、麦角甾醇、角鲨烯、乙酸齿孔醇酯、3α-羟基-4,4,14α-三甲基-Δ2-5α-娠烯-20-酮、去氢齿孔酮酸等。

  • 砂仁中乙酸龙脑酯含量测定

    [align=right][b]SGLC-GC-039[/b][/align][b]摘要:[/b]本文建立了砂仁中乙酸龙脑酯含量测定的GC 方法。结果表明,参照2020版《中国药典》中色谱条件并对升温程序进行优化,采用色谱柱SH-1 分析砂仁中乙酸龙脑酯,乙酸龙脑酯峰形对称,理论塔板数按乙酸龙脑酯峰计算远高于10000,满足《中国药典》要求。此方法可为砂仁中乙酸龙脑酯含量测定提供参考。。[b]关键词:[/b]砂仁 乙酸龙脑酯 SH-1 GC[b]1. 实验部分1.1 实验仪器及耗材[/b]Shimadzu GC-2030[url=https://insevent.instrument.com.cn/t/Mp][color=#3333ff]气相色谱仪[/color][/url];色谱柱:SH-50(30 m,0.25 mm × 0.25 μm;P/N:227-36162-01;S/N:1553669);SHIMSEN Arc Disc HPTFE针式过滤器(P/N:380-00341-05);[url=https://insevent.instrument.com.cn/t/bp][color=#3333ff]GC-MS[/color][/url]认证样品瓶LabTotal Vial(P/N:227-34002-01);SHIMSEN Pipet[url=https://insevent.instrument.com.cn/t/9p][color=#3333ff]移液枪[/color][/url]:SHIMSEN Pipet PMII-10(P/N:380-00751-02);SHIMSEN Pipet PMII-100(P/N:380-00751-04);SHIMSEN Pipet PMII-1000(P/N:380-00751-06)。[b]1.2 对照品溶液的制备[/b]取芳樟醇对照品适量,精密称定,加乙酸乙酯制成每1 mL含0.1 mg的溶液,即得。[b]1.3 供试品溶液的制备[/b]取本品粉末(过三号筛)约1 g,精密称定,置具塞锥形瓶中,精密加入无水乙醇25 mL,密塞,称定重量,超声处理(功率300W,频率40 kHz)30 分钟,放冷,用无水乙醇补足减失的重量,摇匀,滤过,取续滤液,即得。。[b]1.4 分析条件[/b]色谱柱:SH-1 (30 m, 0.25 mm × 0.25 μm P/N:221-75719-30;S/N:1541069 )升温程序:初始温度80 ℃,保持1分钟,以每分钟2 ℃的速率升温至100 ℃,保持5分钟载气:N2进样口温度:230 ℃分流模式:分流(10:1)控制模式:恒线速度(30 cm/s)初始流速:1.09 mL/min检测器:FID,温度:250 ℃进样量:1 μL[b]2. 实验结果[/b]按照上述色谱条件(1.4)进行采集,对照品溶液和供试品溶液色谱图如下:[b]对照品溶液[/b][img=砂仁中乙酸龙脑酯含量测定]https://img.shimadzumall.com/Storage//userfiles/images/Img_articles/SGLC-GC-039_1.png[/img][font=arial, &][size=12px][/size][/font][b]供试品溶液[/b][img=砂仁中乙酸龙脑酯含量测定]https://img.shimadzumall.com/Storage//userfiles/images/Img_articles/SGLC-GC-039_2.png[/img][font=arial, &][size=12px][/size][/font][b]重现性[/b][img=砂仁中乙酸龙脑酯含量测定]https://img.shimadzumall.com/Storage//userfiles/images/Img_articles/SGLC-GC-039_3.png[/img][font=arial, &][size=12px][/size][/font][b]3. 结论[/b]本文建立了砂仁中乙酸龙脑酯含量测定的GC 方法。结果表明,参照2020版《中国药典》中色谱条件,采用色谱柱SH-1 分析砂仁中乙酸龙脑酯,乙酸龙脑酯峰形对称,理论塔板数按乙酸龙脑酯峰计算远高于10000,满足《中国药典》要求。此方法可为砂仁中乙酸龙脑酯含量测定提供参考。

  • 落羽松(落叶乔木)8

    [b][color=#cc0000]落羽松(落叶乔木)8[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081644580836_4737_1841897_3.png[/img]

  • 关于醋酸羟丙甲纤维素琥珀酸酯的游离乙酸和游离琥珀酸的含量分析

    [color=#444444]本人最近按2015版药典做了一个药用辅料-醋酸羟丙甲纤维素琥珀酸酯的的游离乙酸的含量测定实验。实验过程如下:[/color][color=#444444] 游离乙酸、琥珀酸 取本品0.102g,精密称定,置锥形瓶中,精密加入磷酸盐溶液(取0.02mol/L磷酸二氢钾溶液,用1mol/L氢氧化钠溶液调pH值至7.5)4.0ml,搅拌2小时,加磷酸溶液(取1.25mol/L磷酸1ml,置50ml量瓶中,加水稀释至刻度,摇匀)4.0ml,强力振摇,离心,上清液作为供试品溶液;精密称取琥珀酸0.13g,置100ml量瓶中,加水适量,振摇使完全溶解,加水至刻度,摇匀,作为琥珀酸贮备液;取加有水20ml的100ml量瓶,称重,精密加入冰乙酸2ml,再称重,用水稀释至刻度,摇匀,精密量取6ml,置100ml量瓶中,用水稀释至刻度,摇匀,作为乙酸贮备溶液;精密量取乙酸贮备液和琥珀酸贮备液各4.0ml,置同一25ml量瓶中,用流动相稀释至刻度,摇匀,作为对照溶液。照高效液相色谱法(中国药典2015年版四部通则0512)试验。以十八烷基硅烷键合硅胶为填充剂,以0.02moI/L磷酸二氢钾溶液(用6mol/L磷酸溶液调pH值至2.8)为流动相,流速每分钟1ml,检测波长为215nm。取对照溶液10μl, 注入液相色谱仪,按琥珀酸峰计算,理论板数不得少于8000。取供试品溶液与对照溶液各10μl,注入液相色谱仪,按干燥品计算,游离乙酸和琥珀酸总量不得过1.0%。[/color][color=#444444]计算公式: 游离乙酸含量=0.0768(WA/(W(1-干燥失重)))(γUA/γSA)[/color][color=#444444] 式中 WA为乙酸贮备溶液中冰乙酸量,mg;[/color][color=#444444] W为供试品的取样量,mg;[/color][color=#444444] γUA、γSA为供试品溶液、对照溶液中乙酸的峰面积。[/color][color=#444444] 游离琥珀酸含量=1.28(WS/(WUS(1-干燥失重)))(γUS/γSS)[/color][color=#444444] 式中 WS为琥珀酸贮备液中琥珀酸量,mg;[/color][color=#444444] WUS为供试品取样量,mg;[/color][color=#444444] γUS、γSS为供试品溶液、对照溶液琥珀酸的峰面积。[/color][color=#444444]我的问题是,根据“干燥品计算,游离乙酸和琥珀酸总量不得过1.0%”这句话,游离乙酸含量的最后计算的结果要不要乘以100%,比如我最后计算结果是0.0139,如果这个结果再乘以100%,就变为1.39%,从而超过限度,那么就需要重新做实验复核一遍。[/color]

  • 落羽松(落叶乔木)4

    [b][color=#cc0000]落羽松(落叶乔木)4[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081639385847_3470_1841897_3.png[/img]

  • 落羽松(落叶乔木)3

    [b][color=#cc0000]落羽松(落叶乔木)3[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081635397764_8362_1841897_3.png[/img]

  • 落羽松(落叶乔木)7

    [b][color=#cc0000]落羽松(落叶乔木)7[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081643229195_4269_1841897_3.png[/img]

  • 落羽松(落叶乔木)1

    [b][color=#cc0000]落羽松(落叶乔木)1[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081632070977_1357_1841897_3.png[/img]

  • 落羽松(落叶乔木)9

    [b][color=#cc0000]落羽松(落叶乔木)9[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081645539553_4552_1841897_3.png[/img]

  • 落羽松(落叶乔木)6

    [b][color=#cc0000]落羽松(落叶乔木)6[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081641422491_876_1841897_3.png[/img]

  • 落羽松(落叶乔木)2

    [b][color=#cc0000]落羽松(落叶乔木)2[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081633220208_3906_1841897_3.png[/img]

  • 落羽松(落叶乔木)5

    [b][color=#cc0000]落羽松(落叶乔木)5[/color][/b][img]https://ng1.17img.cn/bbsfiles/images/2023/09/202309081640506239_1377_1841897_3.png[/img]

  • 用水做溶剂测定乙酸乙酯残留。如何调整方法?

    [color=#444444]正在做一个物质的溶剂残留,测定目标为乙酸乙酯,样品已知易溶于碱性水溶液,微溶于常用有机溶剂(已经做过甲醇、DMF、DMSO的溶解度试验)。但是问题是乙酸乙酯不溶于水,在配置对照溶液的过程中乙酸乙酯会挥发,重复性惨不忍睹。并且碱用的是氨,挥发时也会带走乙酸乙酯,溶液稳定性相当差。[/color][color=#444444]尝试过向碱溶液加过甲醇等未果,依然难以使溶液稳定。[/color][color=#444444]求教:如何选择溶剂或者改善溶剂来使乙酸乙酯稳定于溶液中?是否可以通过萃取来得到乙酸乙酯?具体如何操作[/color]

  • 气相色谱做肉制品中的脱氢乙酸

    按GB5009。121-2016气相色谱法分析肉制品中的脱氢乙酸,可是我的回收率很低,只有40%左右,我加标后的浓度分别是1ug/mL与10ug/mL,另外还有我的脱氢乙酸的响应信号很低,1ug/mL脱氢乙酸的峰面积只有4,而10ug/mL脱氢乙酸响应信号也只有10左右,按5。1。3的前处理而样液转移到容量瓶时,再转移至分液漏斗中萃取分层时,不好分层,且样品的残渣会堵塞分液漏斗的流出口啊,请教下各位你们是如何处理的

  • 乙酸乙酯标品在气质中不出峰是啥情况

    各位老师,小弟最近在实验室中用气质(瓦里安3800)测香精样品,但是在分析乙酸乙酯时发现找不到对应峰。于是跑了一针乙酸乙酯标样(浓度30ppm,溶剂甲基叔丁基醚),但是还是找不到对应峰,请各个专家指点一二,看看问题究竟出在哪儿。谱库中乙酸乙酯的图谱及标品分析后的谱图如下,请参考。乙酸乙酯的标准质谱图:http://ng1.17img.cn/bbsfiles/images/2017/01/201701231132_01_2297325_3.bmphttp://ng1.17img.cn/bbsfiles/images/2017/01/201701231132_01_2297325_3.bmp乙酸乙酯标样图谱http://ng1.17img.cn/bbsfiles/images/2017/01/201701231134_01_2297325_3.bmp

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