防老剂RD中有效成分含量的测定

分别采用薄层色谱法和高效液相色谱法进行防老剂RD的质量检测。结果表明，薄层色谱半定量法和高效液相色谱法可较准确地进行防老剂RD中多聚体有效成分含量测定，国家标准规定检测项目无法体现防老剂RD的有效成分含量及样品质量。     

胶料混炼过程中防老剂TMQ的有效成分含量变化

利用热重分析和高效液相色谱法,研究防老剂TMQ在不同温度下的热稳定性及其有效成分的含量变化。结果表明：防老剂TMQ在高温下有一定程度的质量损失,其有效成分的含量发生了变化;防老剂TMQ受胶料混炼温度及其添加顺序的影响较大,防老剂TMQ在二段混炼时加入,其有效成分的含量损失率小于防老剂TMQ在一段混炼时加入;当混炼温度为110 ℃时,硫化胶的物理性能较好。     

高效液相色谱法测定防老剂TMQ有效成分含量的不确定度评定

对高效液相色谱法测定防老剂TMQ的主要有效成分2,2,4-三甲基-1,2-二氢化喹啉的二、三、四聚体(简称二、三、四聚体)总含量的不确定度进行评定。建立测定防老剂TMQ的二、三、四聚体总含量的数学模型,分析测量过程中各不确定度来源,包括称取样品质量、容量瓶定容、测量重复性和仪器测量引入的不确定度,并对各个不确定度分量进行量化,得到测量结果的合成标准不确定度与扩展不确定度。     

防老剂RD有效含量的半定量测定

防老剂RD有效含量的测定对于RD生产企业和应用企业都非常重要,它不仅反映产品质量的优劣,还可以促进合成工艺的改进,以及作为产品质量控制手段。根据薄层色谱原理,建立了RD有效含量的半定量测定方法,采用RD有效含量半定量检测箱对某RD助剂厂生产的防老剂RD进行有效含量测定,并用高效液相色谱仪进行定量分析,实验证明两种方法的测定结果趋势一致。     

3种胺类防老剂的检测与分析

采用气相色谱(GC)或高效液相色谱(HPLC)对防老剂4020,3100和RD进行检测和分析。防老剂4020的鉴别可按国家标准指标和GC谱进行;防老剂3100的鉴别除检测国家标准指标外,还应检测3种对苯二胺质量分数和铁质量分数;防老剂RD的鉴别除检测国家标准指标外,还应检测二聚体质量分数和二、三、四聚体总质量分数。建议下游企业用GC或HPLC对防老剂有效成分进行检测。     

防老剂TMQ的总氮含量测定

介绍防老剂TMQ总氮含量的测试步骤和数据处理方法。结果表明:本总氮含量测试方法有效;普通防老剂TMQ的总氮含量控制在7.2%～7.6%之间比较合适,高有效成分含量防老剂TMQ的最佳总氮含量范围需结合胶料性能确定。     

高效液相色谱测定甲胺磷

甲胺磷的分析,国内广泛采用化学法,该法杂质干扰大,薄层色谱法操作麻烦,气相色谱法不稳定。高效液相色谱法手续简便,分析时间短,易掌握,我们对甲胺磷的分析经过半年的探索,证明高效液相色谱法分析甲胺磷准确度高,重现性好,与目前生产厂广泛采用的薄层色谱基本一致。     

高效液相色谱法测定稻棉磷原油和乳油

稻棉磷(mephosfolan)的分析通常采用化学法、气液色谱法和薄层色谱法等,有关稻棉磷的高效液相色谱分析国外文献已有报道。本文就稻棉磷原油及乳剂采用高效液相色谱法定量分析进行了研究,找到了适合稻棉磷原油及乳剂定量分析的色谱条件,其标准偏差在0.8以内,变异系数不大于1.0％,平均回收率为99.95％。     

防老剂TMQ在全钢载重子午线轮胎胎体胶中的应用

考察高二聚体含量防老剂TMQ部分替代防老剂4020在全钢载重子午线轮胎胎体胶中的应用。结果表明:与防老剂4020胶料相比,防老剂4020/TMQ并用的胶料加工安全性能稍好,物理性能变化不大;减小防老剂TMQ用量对胶料耐热氧老化性能影响不大;防老剂TMQ在一定程度上影响钢丝-橡胶的粘合性能,防老剂S-TMQ用量1.05份和防老剂4020用量1份的胶料粘合性能较好,性价比较高。     

硫化胶中防老剂的定性和定量分析

采用气相色谱-质谱（GC-MS）联用仪和提取特征离子的方法对硫化胶中的防老剂进行定性和定量分析。使用高效液相色谱仪对防老剂RD中二聚体和三聚体含量进行测定;采用手动剪样的制样方法,通过超声提取硫化胶中的防老剂,防老剂RD和防老剂4020的提取率分别为73.3%和76.1%,防老剂定量标准曲线的线性关系良好,线性相关因数均大于0.999,防老剂RD和防老剂4020的定量测定相对标准偏差分别为0.58%和1.70%,方法重复性良好;使用已知样品对防老剂定性和定量方法进行验证,结果表明该方法可以进行硫化胶中防老剂的定性和定量分析。     

对二甲苯氧化产物的色谱分析

提出用气相色谱快速定量溶剂醋酸,用液相色谱法快速分析对二甲苯氧化反应体系的所有含苯环的组分的方法。应用Agilent1100高效液相色谱仪,采用D iamonsilC18(D5μm×4.6 mm×150 mm)色谱柱,用甲醇-乙腈-水为流动相,用外标法采用三元梯度洗脱程序分析固相产物中的对羧基苯甲醛和对苯二甲酸含量。以异丙苯为内标物,应用Agilent1100高效液相色谱仪,用甲醇-乙腈-水为流动相,采用三元梯度洗脱程序分析液相产物中的含苯环组分对甲基苯甲醛、对甲基苯甲酸、对羧基苯甲醛、对苯二甲酸、苯甲酸、对二甲苯和内标物异丙苯,应用Sh imazu6A气相色谱仪分析液相中的溶剂醋酸和内标物异丙苯,气相和液相结果通过内标物异丙苯关联。该法准确简捷、且分析周期短。     

表面活性剂配方产品的分析方法及其进展(Ⅱ)——分离技术

介绍了配方产品中表面活性剂的分离技术。一般采用两种路线分离和分析配方产品中的表面活性剂:一是通过离子交换、薄层色谱或柱层析等手段直接得到被分离的组分,以便进一步检测;二是通过气相色谱、高效液相色谱等手段,从仪器的检测和记录系统得到分析结果,但此过程不能直接得到被分离的组分,而高效液相色谱更适用于表面活性剂的分析工作,但往往由于找不到合适的检测系统,应用受到限制。     

TLC Separation of Glucopyranosyl Sinapate and Other Phenolic Compounds from Rapeseed

Glucopyranosyl sinapate was obtained from rapeseeds using column chromatography on Sephadex LH-20 and RP-18 semipreparative HPLC. TLC analysis of this compound, sinapic acid and phenolic compounds fractions from column chromatography were conducted on plates coated with silica gel (standard and HPTLC), with cellulose and on RP-TLC plates. Eleven various solvent systems were applied to develop chromatograms. HPTL plates were found more efficient than those coated with standard silica gel. Compared to the latter cellulose ensured worse results of TLC analysis. The best developing system for plates coated with silica gel was benzene-methanol-acetic acid (90:16:8). Separation of the compounds analysed using RP-TLC depended on octadodecylsilanization degree of silica gel on TLC plate.     

高效液相色谱法测定环境样品中的酞酸酯

研究了高效液相色谱法测定环境样品中酞酸酯含量的色谱分离条件,采用薄层色谱预分离的方法减少杂质峰对样品的干扰,对部分月份环境样品中的酞酸酯富集程度进行了检测。     

粉状化妆品中9种有机着色剂的高效液相法测定

建立了用高效液相色谱（HPLC）/二极管阵列检测器（DAD）同时检测粉状化妆品中多种有机着色剂的检测方法。样品采用甲醇＋水（1：1）提取溶剂超声提取15min后,以乙腈-磷酸二氢钾缓冲溶液（pH=6）为流动相梯度洗脱,在240nm的波长下用DAD对9种目标物同时进行检测。用保留时间结合目标化合物的紫外吸收光谱定性,外标法定量。方法的平均回收率（n=9）在90.31％-99.10％的范围内,精密度RSD在1.95％-4.61％之间。方法简单、快速,能有效提取和分离测定粉状化妆品中多种有机着色剂。将该方法用于实际样品的检测,结果令人满意。     

Triacylglycerol composition of Pinus koraiensis seed oil

The triacylglycerol (TG) composition of Pinus koraiensis seed oil, which contains Δ5 nonmethylene-interrupted (NMI) fatty acids (FA) (the main acid is pinolenic, 18:3 Δ5, 9, 12), was determined. TG were preliminarily separated by argentation thin-layer chromatography (TLC), and the obtained fractions were analyzed by high-temperature gas chromatography (GC) on a capillary column with methyl phenyl silicone phase. Additionally, high-performance liquid chromatography (HPLC) of TG was applied. The FA composition of all TG fractions was identified. The identification of TG was carried out by combining TLC, GC, HPLC, and calculated equivalent carbon numbers of TG standards. The TG species identification was confirmed by comparison of the theoretical recalculated and directly analyzed FA compositions of all TLC fractions of TG. Species of TG with unsaturation degrees of 1 to 7 and trace amounts of saturated and octaenoic TG species were found. Except for minor compounds, 26 TG molecular species of 32 main components were quantitatively determined. The main species were oleoyl dilinoleoylglycerol (14.7%), dilinoleoyl pinolenoylglycerol (10.7%), palmitoyl oleoyl linoleoylglycerol (8.3%), triolein (7.6%), and dioleoyl, linoleoylglycerol (7.4%). Seven TG species contained Δ5 NMI acyl groups. Of these, the major were dilinoleoyl pinolenoyglycerol (10.7%), stearoyl linoleoyl pinolenoylglycerol (6.5%) dioleoyl, pinolenoylglycerol (5.4%), and palmitoyl linoleoyl pinolenoyl-glycerol (5.5%). TG species with two or three NMI acyl groups were not detected.     

Rapid Detection and Quantification of Triacylglycerol by HPLC–ELSD in Chlamydomonas reinhardtii and Chlorella Strains

Triacylglycerol (TAG) analysis and quantification are commonly performed by first obtaining a purified TAG fraction from a total neutral lipid extract using thin-layer chromatography (TLC), and then analyzing the fatty acid composition of the purified TAG fraction by gas chromatography (GC). This process is time-consuming, labor intensive and is not suitable for analysis of small sample sizes or large numbers. A rapid and efficient method for monitoring oil accumulation in algae using high performance liquid chromatography for separation of all lipid classes combined with detection by evaporative light scattering (HPLC–ELSD) was developed and compared to the conventional TLC/GC method. TAG accumulation in two Chlamydomonas reinhardtii (21 gr and CC503) and three Chlorella strains (UTEX 1230, CS01 and UTEX 2229) grown under conditions of nitrogen depletion was measured. The TAG levels were found to be 3–6 % DW (Chlamydomonas strains) and 7–12 % DW (Chlorella strains) respectively by both HPLC–ELSD and TLC/GC methods. HPLC–ELSD resolved the major lipid classes such as carotenoids, TAG, diacylglycerol (DAG), free fatty acids, phospholipids, and galactolipids in a 15-min run. Quantitation of TAG content was based on comparison to calibration curves of trihexadecanoin (16:0 TAG) and trioctadecadienoin (18:2 TAG) and showed linearity from 0.2 to 10 μg. Algal TAG levels >0.5 μg/g DW were detectable by this method. Furthermore TAG content in Chlorella kessleri UTEX 2229 could be detected. TAG as well as DAG and TAG content were estimated at 1.6 % DW by HPLC–ELSD, while it was undetectable by TLC/GC method.     

Analysis of aldehydic lipid peroxidation products by TLC/densitometry

We have explored the use of thin-layer chromatography (TLC)/densitometry in both the reflectance and fluorescence mode for quantitation of specific products of lipid peroxidation. Aldehydic peroxidation products were generated by exposure of arachidonic acid to iron and ascorbic acid for 24 hr. Several methods for the quantitative analysis of peroxidation products by TLC/densitometry were compared using two different aldehydespecific derivatizing reagents, namely dinitrophenylhydrazine (DNPH) and cyclohexanedione (CHD). DNPH hydrazones of the arachidonic acid-peroxidation products, upon TLC separation on silica gel, revealed prominent alkanal and hydroxyalkenal bands. Reverse phase high performance liquid chromatography confirmed that the primary alkanal component was hexanal, while the primary hydroxyalkenal was 4-hydroxynonenal. Semiquantitative methods for the direct analysis of these products by TLC/densitometry were worked out based on the use of external hydrazone standards. TLC/densitometry (fluorescence mode) was used to measure CHD adducts of aldehydes by forming the derivatives in the presence of decanal (used as an internal standard) and separating the derivatives by reverse phase TLC. Hexanal-CHD was detectable upon application of 0.5 nanomoles while 4-hydroxynomenal showed a lower response and was detectable with 10 nanomoles. Using appropriate response factors, hexanal and 4-hydroxynonenal were measured in the aldehyde sample from arachidonic acid and results were similar to those obtained by the DNPH method. Similar approaches were used to analyze the peroxidation products of docosahexaenoic acid (24-hr exposure) The DHA peroxidation products contained extremely low levels of alkanals, while polar aldehydes and hydroxyalkenals were prominent. Formation of alkanals, osazones, hydroxyalkenals and phospholipid aldehydes from iron-exposed microsomes was also demonstrated. Uses and limitations of these methods of aldehyde measurement are discussed.     

亚硝基草甘膦高效液相色谱法定量分析研究

通过试验优化了亚硝基草甘膦的外标法定量分析。建立了亚硝基草甘膦的快速定量测定方法,样品经硫酸水溶液来处理,高效液相色谱外标法定量。结果表明方法的标准偏差为0.04;变异系数为2.98%;平均回收率为97.31%~99.42%,线性范围为25~200μg/mL,最低检测限为5μg/mL,该方法简便快速而易于操作。适用于草甘膦原药生产对亚硝基草甘膦的质量控制。     

Regioselective analysis of the fatty acid composition of triacylglycerols with conventional high-performance liquid chromatography

A new method for regioselective analysis of triacyglycerols via conventional high-performance liquid chromatography (HPLC) has been developed. The method is simple and avoids the time-consuming purification processes normally characteristics of regioselective analyses. The procedure utilizes an sn-1,3-specific lipase from Rhizopus arrhizus to deacylate the fatty acid residues located at the sn-1 and sn-3 positions of triacylglycerols. The fatty acid residues esterified at the sn-2 position are determined by subtraction of the results of the sn-1,3 analysis from an overall composition analysis based on complete saponification of the original sample. The fatty acid mixtures are converted to p-bromophenacyl esters and analyzed using conventional HPLC techniques. The analytical procedure has been verified using a standard structured triacylglycerol. The analytical results for three edible vegetable oils are compared with those obtained via the method proposed by P.J. Williams and co-workers.