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1.
陈会明  王超 《分析化学》2004,32(2):271-271
为了保证化妆品质量,要添加一定量的抗氧化剂。但抗氧化剂过量,会损害人体健康。合格食品的抗氧化剂的添加量必须符合国家卫生标准。卫生部对化妆品中丁基羟基茴香醚(BHA)和二丁基羟基甲苯(BHT)的最大限量要求均为0.15%,但化妆品中BHA和BHT尚无行业及国家卫生检验标准。食品中抗氧化剂的测定一直沿用薄层法、比色法和气相  相似文献   

2.
建立了改变检测波长测定喜树种子中喜树碱和 10 羟基喜树碱的高效液相色谱法。使用TechspheseODSC18(4.6mm× 2 5cm ,5 μm)色谱柱 ,以水∶乙腈 =3∶7(V/V)为流动相 ,流速为 1.0mL/min ,2 5℃下检测。检测波长 :0~ 8min时为 2 6 6nm ,8~ 2 0min时为 2 5 4nm。结果表明 :喜树碱的平均回收率为 10 0 .92 % ,RSD值 1.4 0 % ;羟基喜树碱的平均回收率为 10 0 .0 9% ,RSD值 1.34%。此方法简单、可靠。  相似文献   

3.
2-羟基-3-甲氧基苯基荧光酮光度法测定合金钢中的微量钼   总被引:1,自引:0,他引:1  
研究钼 (Ⅵ )与 2 羟基 3 甲氧基苯基荧光酮 (HMPF)的显色反应。在磷酸介质中 ,在阳离子表面活性剂CTMAB作用下 ,钼 (Ⅵ )与HMPF形成红色配合物 ,其最大吸收波长为 5 2 5nm ,表观摩尔吸光系数为 1.34× 10 5L/ (mol·cm) ,钼的浓度在 0~ 15 μg/(2 5mL)范围内服从比耳定律。可不经分离测定合金钢中的钼。用该法测定合金钢标准样品中的钼 ,测定结果与标准值相吻合 ,RSD为 0 .85 %~ 1.5 2 %。  相似文献   

4.
研究了铅与二溴羟基苯基荧光酮在阳离子表面活性剂十六烷基三甲基溴化铵存在下的显色反应。在硼酸盐缓冲介质中铅与二溴羟基苯基荧光酮在十六烷基三甲基溴化铵 ( CTMAB)存在下形成红色络合物 ,最大吸收波长为 5 4 0 nm,表观摩尔吸光系数为 6.1× 1 0 4 L· mol- 1· cm- 1。铅含量在 0~ 30μg/2 5 m L符合比耳定律。本法应用于测定市售化妆品、人工湖水中的铅 ,结果准确可靠  相似文献   

5.
建立了向量–子空间夹角判据结合紫外分光光度法测定植物油中3种抗氧化剂的方法,可用于植物油中特丁基对苯二酚(TBHQ)、丁基羟基茴香醚(BHA)、二丁基羟基甲苯(BHT)3种抗氧化剂的同时快速分析。采用紫外光谱–高效液相色谱(UV-HPLC)联用方法对植物油样品进行分离,构建不含待测组分的本底光谱数据库,基于向量-子空间夹角判据算法的步骤分析植物油中3种抗氧化剂的含量。实际样品加标回收率在95.2%~103.3%之间,RSD小于3%(n=6)。对市售15种植物油样品进行分析,其中12种植物油样品检出TBHQ,含量为21.34~30.12μg/m L,15种植物油样品均未检出BHA和BHT。方法适用于植物油中TBHQ,BHA和BHT 3种抗氧化剂的同时快速分析。  相似文献   

6.
合成了 2 羟基 4 磺酰氨基苯重氮氨基偶氮苯 (HSDAA) ,并研究了在TritonX 1 0 0表面活性剂存在下HSDAA与镉的显色反应。在pH 8 5~ 1 0 5的Na2 B4 O7 NaOH缓冲溶液中 ,该试剂与镉生成 2∶1型深红色配合物。配合物的最大吸收峰位于 5 2 5nm处 ,表观摩尔吸光系数达 1 84× 1 0 5L·mol- 1·cm- 1。ρ(Cd2 + )在 0~ 480 μg/L范围内符合比耳定律。用拟定方法测定样品中的微量镉 ,结果满意。  相似文献   

7.
建立高效液相色谱法测定芝麻油中叔丁基羟基茴香醚(BHA)、2,6-二叔丁基对甲酚(BHT)、特丁基对苯二酚(TBHQ)的含量。用25 mL甲醇分5次涡旋超声提取芝麻油中的BHA,BHT,TBHQ,以La Chrom C18(250mm×4.6 mm,5μm)为色谱柱,以甲醇–0.5%甲酸水溶液为流动相进行梯度洗脱,流量为1.0 mL/min,进样体积为5μL,柱温为35℃,检测波长为280 nm。BHA,BHT,TBHQ的质量浓度在20~300 mg/L范围内与其色谱峰面积呈良好的线性关系,相关系数大于0.999,方法检出限为0.5~1.0 mg/kg。样品加标回收率为95.1%~99.8%,测定结果的相对标准偏差为2.1%~4.7%(n=6)。该方法操作简单,试剂用量少,准确度高,精密度好,适用于芝麻油中BHA,BHT,TBHQ含量的日常检测。  相似文献   

8.
基于金属有机骨架的拓扑三维结构的高比表面积以及金纳米颗粒(Au NPS)的优异电催化活性,金纳米颗粒与金属有机框架的复合材料在电化学传感领域拥有应用潜力。该文成功合成了Au NPs@NU-901复合材料,并采用透射电镜、X射线衍射、红外光谱以及X射线光电子能谱对其进行表征。采用线性扫描伏安法和差分脉冲伏安法研究了复合材料对丁基羟基茴香醚(BHA)电化学氧化反应的催化能力。结果表明,Au NPs@NU-901对BHA的电化学氧化具有较好的催化能力。基于Au NPs@NU-901制备电化学传感器用于BHA的定量检测,BHA的氧化峰电流与其浓度在0.10~50 μmol/L范围内呈现良好线性关系,相关系数(r2)为0.994 8,检出限(S/N=3)为0.049 μmol/L,相对标准偏差(RSD)为3.6%。将该传感器应用于饼干样品中BHA的检测,加标回收率为95.6%~104%,样品检测结果与高效液相色谱法的测定结果吻合。方法的选择性好、灵敏准确,适合于饼干中BHA的检测。  相似文献   

9.
合成了新的三氮烯试剂2 羟基4 磺酰氨基苯3 (4 硝基苯) 三氮烯(HSNPT) ,并研究了在TritonX 1 0 0表面活性剂存在下与镍的显色反应。在pH 1 0~1 2. 0的Na2 B4 O7 NaOH缓冲溶液中,试剂与镍形成配合比为3∶1型淡黄色配合物。配合物最大负吸收峰位于λ=5 40nm处,表观摩尔吸光系数1 .1 8×1 0 5L·mol- 1·cm- 1。Ni2 +的质量浓度在0~480 μg/L范围内符合比尔定律。用拟定方法测定合金钢样品中的微量镍,结果满意。  相似文献   

10.
本文研究了新试剂7-(2,4,6-三羟基苯偶氮)-8-羟基喹啉-5-磺酸(THBAQS)与锆、铪的显色反应.酸性条件下锆、铪均可形成 M-THBAQS-CTMAB三元络合物,ε_(315nm)~(Zr)=3. 27×10~4,ε_(515nm)~(HI)=3.8×10~4,适量H_2O_2使锆络合物吸光度显著降低,据此实现了锆铪的同时测定.本法简便快速、适用范围为0~30μgZr/25 mL,0~25μg Hf/25 mL,且X_(Zr)+X_(Hf)<35μg/25 mL.  相似文献   

11.
气相色谱法测定高分子食品包装材料中抗氧化剂的残留量   总被引:5,自引:0,他引:5  
Xiong Z  Wang L  Li N  Yu Y  Jia X 《色谱》2011,29(3):273-276
建立了气相色谱测定高分子食品包装材料中抗氧化剂丁基羟基茴香醚(BHA)、二丁基羟基甲苯(BHT)和特丁基对苯二酚(TBHQ)残留量的分析方法。用环己烷超声萃取高分子食品包装材料样品,考察了萃取时间、温度对抗氧化剂萃取量的影响。萃取液经气相色谱柱HP-50+毛细管柱(30 m×0.53 mm×1 μm)分离,电子捕获检测器(ECD)检测,外标法定量。结果表明: 在抗氧化剂添加量为3.00~10.0 mg/kg范围内,BHT、BHA、TBHQ在高分子食品包装材料中的平均添加回收率分别为88%~93%、92%~101%和83%~97%,相对标准偏差(RSD, n=5)分别为2.01%~2.89%、2.11%~3.19%和2.99%~4.02%;检出限(信噪比为3)分别为0.5、0.5和0.8 mg/kg。对实际高分子食品包装材料样品的检测结果表明3种抗氧化剂在不同材质中均有检出: 塑料材料中抗氧化剂的含量较少,仅有BHT、BHA被检出,含量为6.3~7.8 mg/kg;橡胶材料中3种抗氧化剂均被检出,含量为9.3~28.4 mg/kg。该方法准确、灵敏、重现性好,适用于高分子食品包装材料中抗氧化剂残留量的检测。  相似文献   

12.
A simple electrochemical method was developed for the single and simultaneous determination of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in food samples using square-wave voltammetry (SWV). A carbon composite electrode modified (MCCE) with copper (II) phosphate immobilized in a polyester resin was proposed. The modified electrode allowed the detection of BHA and BHT at potentials lower than those observed at unmodified electrodes. A separation of about 430 mV between the peak oxidation potentials of BHA and BHT in binary mixtures was obtained. The calibration curves for the simultaneous determination of BHA and BHT demonstrated an excellent linear response in the range from 3.4 × 10−7 to 4.1 × 10−5 mol L−1 for both compounds. The detection limits for the simultaneous determination of BHA and BHT were 7.2 × 10−8 and 9.3 × 10−8 mol L−1, respectively. In addition, the stability and repeatability of the electrode were determined. The proposed method was successfully applied in the simultaneous determination of BHA and BHT in several food samples, and the results obtained were found to be similar to those obtained using the high performance liquid chromatography method with agreement at 95% confidence level.  相似文献   

13.
Electrochemical behavior of three antioxidants: butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and butylated hydroquinone (TBHQ), was investigated at a glassy carbon electrode modified with gold nanoparticles (AuNPs/GCE). This electrode was characterized by scanning electron microscopy (SEM). The experimental results indicated that the modified electrode was strongly electroactive during the redox reactions of BHA, BHT and TBHQ, and this was confirmed by the observed increased redox peak currents and shifted potentials; in addition, the oxidation products of BHA and TBHQ were found to be the same. The experimental conditions were optimized and the oxidation peaks of BHA and BHT were clearly separated. Based on this, an electrochemical method was researched and developed for the simultaneous determination of BHA, BHT and TBHQ in mixtures with the use of first derivative voltammetry; the linear concentration ranges were 0.10–1.50 μg mL−1, 0.20–2.20 μg mL−1 and 0.20–2.80 μg mL−1, and detection limits were 0.039, 0.080 and 0.079 μg mL−1, for BHA, BHT and TBHQ, respectively. The proposed method was successfully applied for the analysis of the three analytes in edible oil samples.  相似文献   

14.
建立了同时测定植物油中BHA、BHT、TBHQ等3种酚类抗氧化剂的测定方法。样品中的抗氧化剂经石油醚提取、乙腈萃取后采用HP-5毛细管柱分离。样品加标回收率为82.8?.6%,相对标准偏差为1.06%~3.11%,BHA、BHT、TBHQ的最低检出量分别为5、10、5ng。该方法具有快速、灵敏度高、重现性好、前处理简单等优点。  相似文献   

15.
高效液相色谱法测定食品中抗氧化剂BHA,BHT,PG   总被引:3,自引:0,他引:3  
李桂凤  郝征红  董淑敏 《色谱》1998,16(3):276-277
 用反相高效液相色谱法同时测定了食品中抗氧化剂丁基羟基茴香醚(BHA)、二丁基羟基甲苯(BHT)和焦性没食子酸丙酯(PG)。样品用正己烷提取,氮气吹干,水-乙醇(14,V/V)溶解残留物,经0.5μm滤膜过滤,直接进样。方法简便、快速、回收率高、重现性好。  相似文献   

16.
《Analytical letters》2012,45(6):1123-1137
Abstract

The UV-derivative spectrophotometric method was used for assaying butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and propyl gallate (PG) in pure state and in laboratory mixtures. Ir; this paper the results are presented using zero-crdssing technique. In this way, thc interference of two components mixed together has been eliminated. That is the greatest advantage of derivative spectroscopy compared with the classical UV-spectrophotometric method. After analysing the criteria f o r the application of this method, the amounts of these substances were determined. Simul taneously, a highperformance liquid chromatography was used.  相似文献   

17.
The ethanol extracts of Morchella vulgaris (EEMV) and Morchella esculanta (EEME) were analysed for their antioxidant activities in different systems including reducing power, free radical scavenging, superoxide anion radical scavenging, total antioxidant activity, and metal chelating activity. EEMV and EEME had similar reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activity at concentrations of 50, 100, and 150 microg/mL. These various antioxidant activities were compared to standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and alpha-tocopherol. The percent inhibition of different concentrations of EEMV on peroxidation in the linoleic acid system was 85 and 87 % respectively, which was greater than that of 100 and 250 microg/mL of alpha-tocopherol (50 and 77%, respectively) and similar to 250 microg/mL of BHA (85, 87%, respectively). The percent inhibition of different concentrations of EEME on peroxidation in the linoleic acid system was 80 and 87 % respectively, which was greater than that of 100 and 250 microg/mL of alpha-tocopherol (50, 77%) and similar to 250 microg/mL BHA (87%). On the other hand, the percent inhibition of 100 and 250 microg/mL of BHT was 97 and 99%, respectively. In addition, the total phenolic compounds in EEMV and EEME were determined as gallic acid equivalents.  相似文献   

18.
Summary A method for the qualitative detection of antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), the gallates and nordihydroguajaretic acid (NDGA) in bakery products and fat has been tested in a collaborative study. The method is similar to a IUPAC-method, an EEC-proposed method, and an official French method. After extraction, the compounds are detected by TLC. Being a qualitative method the probability of obtaining correct results is a measure of the goodness of the method, and the study examines the influence on the probability of the following 3 factors: type of antioxidant, type of food, and concentration of antioxidant. From the study is was concluded that the method worked quite well for BHA, with a detection limit about 15 mg/kg, whereas it worked badly for BHT, the detection limit being higher than 30 mg/kg. For the gallates and NDGA the detection limit was 30 mg/kg. Maize oil disturbed the readings on the TLC-plate, and cakes give more correct results than oil/fat.
Gemeinschaftsuntersuchung einer qualitativen DC-Methode zum Nachweis von Antioxidantien (BHA, BHT, Gallate, NDGA) in Lebensmitteln
Zusammenfassung Ein Nachweisverfahren für Antioxidantien (butyliertes Hydroxyanisol BHA, butyliertes Hydroxytoluol BHT, Gallate, Nordihydroguajaretsäure NDGA) in Backwaren und Fett wurde im Rahmen einer Gemeinschaftsuntersuchung getestet. Die Methode ist ähnlich einer IUPAC-Methode, einem EEC-Vorschlag sowie einer amtlichen französischen Methode. Die DC-Trennung erfolgt nach Extraktion. Der Einfluß folgender 3 Faktoren auf die Güte der Ergebnisse wurde geprüft. Art des Antioxidans, Art des Lebensmittels, Konzentration des Antioxidans. Es ergab sich, daß die Methode für BHA gut brauchbar ist (Nachweisgrenze 15 mg/kg), während sie für BHT Nachweisgrenzen von über 30 mg/kg aufweist. Für Gallate und NDGA liegt die Nachweisgrenze bei 30 mg/kg. Maisöl stört die Ablesungen auf der DC-Platte. Bei Backwaren werden bessere Ergebnisse erhalten als bei Ölen und Fetten.
  相似文献   

19.
Guan Y  Chu Q  Fu L  Ye J 《Journal of chromatography. A》2005,1074(1-2):201-204
A new and efficient method for the determination of antioxidants [Propyl gallate (PG), tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT)] in cosmetics has been established by using micellar electrokinetic capillary chromatography with electrochemical detection (MECC-ED). Under the optimum conditions of the method, all analytes were successfully separated within 13 min at the separation voltage of 18 kV in a 20 mmol/L borate running buffer (pH 7.4) containing 25 mmol/L sodium dodecyl sulfate. The excellent linearity was obtained in the concentration range from 5.0 x 10(-4) to 2.0 x 10(-6) mol/L and the detection limits (S/N = 3) of PG, TBHQ, BHA, and BHT range from 3 x 10(-7) to 3 x 10(-6) mol/L.  相似文献   

20.
NaBHT (sodium butylated hydroxytoluene), a hindered and soluble base for the efficient arylation of various base-sensitive amines and (hetero)aryl halides has been found to have an unanticipated role as a hydride donor to reduce (hetero)aryl halides and allylic acetates. Mechanistic studies have uncovered that NaBHT, but not BHT, can deliver multiple hydrides through oxidation of the benzylic methyl group in NaBHT to the aldehyde. Further, performing the reduction with NaBHT-d20 has revealed that the redox-active benzylic position is not the only hydride donor site from NaBHT with one hydride in three coming, presumably, from the tert-butyl groups. The reduction works well under mild conditions and, incredibly, only consumes 20 percent of the NaBHT in the process; the remaining 80 percent can be readily recovered in pure form and reused. This, combined with the low cost of the material in ton-scale quantity, makes it practical and attractive for wider use in industry at scale.  相似文献   

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