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1.
盐酸美西律对映体的毛细管电泳分离   总被引:4,自引:0,他引:4  
康经武  孙增培 《分析化学》1997,25(3):290-293
以β-环糊精的两种生物做为毛细管电泳手性分离添加剂,对盐酸美西律的对映体进行了拆分研究。其中,2,6-O-二甲基β-环糊精可将对映体部分拆分,而2,3,6-O-三甲基β-环糊精时,可基线分离对映体。研究了两种甲基化β-环糊精的浓度及工作电压对分离的影响。  相似文献   

2.
水果中三唑酮残留量的气相色谱和气相色谱—质谱分析   总被引:10,自引:0,他引:10  
周昱  林立毅 《分析化学》1997,25(5):510-514
水果中三唑酮残留用丙酮提取,经液-液分配净化,用气相色谱-电子捕获检测器测定,并用相色谱-质谱进行确证以HP-5大口径毛细管柱和HP-5MS毛细管柱为分离柱,选择出合适的色谱条件。三唑酮的分离效果良好。  相似文献   

3.
李永田  杨志勇 《分析化学》1995,23(3):297-298
本文用反相液相色谱法对同分异构体多环芳烃Qu和1,2-苯并蒽进行分离,固定其它全部色谱条件观察了30--7℃条件下的分离情况,结果发现,30-0℃左右,该两种物质始终不能分离,-4℃时见分离趋势,-7℃时分离较为满意,认为低温液相色谱可用于某些同分异构体等难分离物质的分离。  相似文献   

4.
刘爱华  周良模 《分析化学》1997,25(11):1282-1284
在七(2,6-二-O-正戊基-3-O-三氟乙酰基)-β-环糊精手性固定相上分离除虫 药菊酸乙酯,顺式菊酸乙酯可达基线分离,反式可达到半高峰宽以下分离,证明为一种较好的固定相,并从热力学角度探讨了其分离机理。  相似文献   

5.
本文报道一种以β-环糊精为手性分离试剂,毛细管电泳分离二氧异丙嗪对映体的新方法,详细研究了溶液pH值,β-环糊精浓度和电解质浓度等对二氧异丙嗪对异体分离的影响。  相似文献   

6.
首次用高效离心分配色谱仪(HPCPC)研究用异丙基膦酸单(1-己基-4-已基)辛酯(PT-2)分离三价重稀土元素,以分离 Yb(Ⅲ), Er(Ⅲ)及 Lu(Ⅲ)为例,考察了流动相酸度、流速、固定相浓度、HPCPC的转速等因素对HPCPC分离稀土效果的影响,并用HPCPC法和液-液萃取法研究了PT-2萃取重稀土的机理。  相似文献   

7.
以葡萄糖和哌啶为原料,合成、分离并鉴定了2,3-二氢-3,5-二羟基-6-甲基-4-(H)吡喃-4-酮(1),以空气氛下直接热裂解,SPME吸附热裂解挥发生产物的方式,分析鉴定了20个裂解的挥发性化合物,讨论了热裂解的可能过程。  相似文献   

8.
本文应用高效液相色谱法.在C18反相柱上,以0.25mol/L乳酸作流动相,采取pH梯度.对16个稀土元素进行分离。除Dy-Y和Gd-Eu两对未完全分离外.其余稀土在55min全部洗脱达到分离、对完全分开的稀土元素,采用内标法同时定量测定.而两对元素Dy-Y和Gd-Eu采用铁消因子分析方法,进行了定量计算,取得了满意的结果。  相似文献   

9.
壳聚糖交联膜电渗析法分离氟、氯、砷的研究   总被引:1,自引:0,他引:1  
用壳聚糖交联膜电渗析方法,分离去除Cl-、F-以及AsO-2,并考查了其分离的最佳条件,如槽电压、酸度、浓度等,并通过其对Cl-、F-的分离与目前极具权威的AEM对F-、Cl-分离进行比较看出:两者的分离效果极为相近.所以把壳聚糖交联膜用于工业生产中前景可观.  相似文献   

10.
渗透汽化分离苯—乙醇混合物   总被引:2,自引:0,他引:2  
以甲基硅橡胶及甲基丙烯酸十二酯-甲基丙烯酸异丁酯的共聚物共为膜材料,以聚丙烯睛多孔膜为底膜制成复合膜,对苯-乙醇混合物进行渗透汽化分离。考察了膜材料的组成、分离温度、原料液组分等因素对膜性能的影响。  相似文献   

11.
建立了以离子液体和β-环糊精为添加剂的反向微乳毛细管电泳(MEEKC)法分离测定化妆品中丙酸氟替卡松、曲安奈德、醋酸可的松、地塞米松、氢化可的松和泼尼松6种激素的方法.在优化的实验条件下,6种物质于12min内达到基线分离,丙酸氟替卡松在2.0~200mg/L范围内线性关系良好,其它组分在2.0 ~ 500mg/L范围内线性关系良好,检出限(S/N =3)分别为0.75、0.81、0.66、0.68、0.74、0.86 mg/L.方法用于化妆品样品测定,加标回收率在93.5%~105%之间,RSD均小于4.3%(n=3).  相似文献   

12.
A multiresidue method for the determination of 12 glucocorticoids (clobetasol propionate, budesonide, triamcinolone, triamcinolone acetonide, fludrocortisone acetate, flumethasone, beclomethasone, prednisone acetate, 6‐α‐methylprednisolone, hydrocortisone, cortisone, and prednisone) in bovine milk was developed using liquid chromatography with tandem mass spectrometry. Isoflupredone was used as an internal standard. Milk samples were treated with ethyl acetate to extract glucocorticoids and were frozen at −20°C for 6 h to precipitate fat. The extract was dried under nitrogen, and residues were dissolved in an acetonitrile/water solution. A further clean‐up step was used by dispersive solid‐phase extraction, with octadecyl silica and primary secondary amine as the absorbents. The recoveries of glucocorticoids spiked at 0.5, 1.0, 10.0 μg/kg ranged from 75.7 to 117.3%, except for clobetasol propionate and budesonide (16.1–49.5%). The limits of quantification were 0.01–0.5 μg/kg in milk. This method has been successfully applied in real samples. The results demonstrated that this method is simple, robust, and suitable for identification of glucocorticoid residues in milk.  相似文献   

13.
建立了鸡肉和鸡蛋中合成类固醇类激素(睾酮、甲基睾酮、群勃龙、勃地龙、诺龙、美雄酮、司坦唑醇、丙酸诺龙、丙酸睾酮及苯丙酸诺龙)和糖皮质类激素(泼尼松、泼尼松龙、地塞米松、氟氢可的松、甲基泼尼松、倍氯米松及氢化可的松)多残留的液相色谱-串联质谱(LC-MS/MS)检测方法.样品经乙腈超声提取,正己烷脱脂净化,以甲醇-甲酸水溶液为流动相,经C18柱分离后进行LC-MS/MS选择反应监测模式下的定性及定量分析.合成类固醇类激素采用正离子模式检测,糖皮质激素则采用负离子模式检测,正、负离子化模式一次进样同时检测.类固醇类和糖皮质类激素的定量检出限为0.5 μg/kg.在0.5、 1.0和5.0 μg/kg 3种浓度添加水平,上述激素的平均回收率为73.4%~108.9%;相对标准偏差为3.4%~13.4%.可实现样本灵敏、准确地定性定量分析.  相似文献   

14.
Summary The previously described analytical method for carbohydrates, catecholamines, uric acid, creatine and creatinine using thin-layer chromatography on aminomodified HPTLC plates and subsequent thermal activation of the chromatogram zones is expanded to include several steroid hormones. Specifically, they are the pharmacologically relevant compounds cortisone and hydrocortisone, estradiol and estradiol benzoate, estriol, estrone, methyltestosterone, testosterone and testosterone propionate, prednisolone, pregnandiol and triol, progesterone and Reichstein's S.  相似文献   

15.
Two simple and rapid LC/MS methods with direct injection analysis were developed and validated for the quantification and identification of hydrocortisone in equine urine using the same sample preparation but different mass spectrometric systems: ion trap mass spectrometry (IT-MS) and time-of-flight mass spectrometry (TOF-MS). The main advantage of the proposed methodology is the minimal sample preparation procedure, as particle-free diluted urine samples were directly injected into both LC/MS systems. Desonide was used as internal standard (IS). The linear range was 0.25-2.5 microg ml(-1) for both methods. Matrix effects were evaluated by preparing and analyzing calibration curves in water solutions and different horse urine samples. A great variation of the signal both for hydrocortisone and the internal standard was observed in different matrices. To overcome matrix effects, the unavailability of blank matrix and the excessive cost of the isotopically labeled internal standard, standard additions calibration method was applied. This work is an exploration of the performance of the standard additions approach in a method where neither nonisotopic internal standards nor extensive sample preparation is utilized and no blank matrix is available. The relative standard deviations of intra and interday analysis of hydrocortisone in horse urine were lower than 10.2 and 5.4%, respectively, for the LC/IT-MS method and lower than 8.4 and 4.4%, respectively, for the LC/TOF-MS method. Accuracy (bias percentage) was less than 9.7% for both methods. Copyright (c) 2008 John Wiley & Sons, Ltd.  相似文献   

16.
HPLC法测定氯霉素氢化可的松滴耳液中两组分的含量   总被引:1,自引:0,他引:1  
李小燕 《色谱》1998,16(1):71-73
采用反相高效液相色谱法,以醋酸泼尼松为内标,UV检测波长为244nm,以YWG-C18为固定相,以甲醇-水(60∶40)为流动相,同时测定了氯霉素氢化可的松滴耳液中氯霉素和氢化可的松的含量,并进行了线性范围和回收率测定,平均回收率(n=6)和相对标准偏差分别为:99.91%和0.86%(氯霉素),99.58%和1.34%(氢化可的松)。  相似文献   

17.
A high-performance liquid chromatographic method is described for the simultaneous determination of methylprednisolone (MP) and methylprednisolone hemisuccinate (MPHS), or hydrocortisone (HC) and hydrocortisone hemisuccinate (HCHS) in human serum. Reversed-phase liquid chromatography was performed on a microparticulate C18 column (Spherisorb, 5 micron) using a mobile phase of 2% glacial acetic acid, 30--35% acetonitrile, 70--65% water with ultraviolet detection (254 nm). The method uses 17 alpha-hydroxyprogesterone as the internal standard for the determination of methylprednisolone and its hemisuccinate ester, or 11-deoxy-17-hydroxycorticosterone as the internal standard for the determination of hydrocortisone and its hemisuccinate ester. The sensitivity is 0.03 microgram/ml for HC, 0.07 microgram/ml for MP, 0.04 microgram/ml for MPHS, and 0.10 microgram/ml for HCHS, with a detection limit of 0.02 microgram/ml for all four steroids. Calibration curves are linear up to 3 micrograms/ml for MP or MPHS (as equivalent MP) and up to 4 micrograms/ml for HC and 7 micrograms/ml (as equivalent HC) for HCHS. The pooled relative standard deviation for replicate for each steroid is less than 7%. Plasma concentration--time curves are reported for MP and MPHS or HC and HCHS of two human subjects following intramuscular administration of 125 mg of methylprednisolone sodium succinate for injection, U.S.P., or 250 mg of hydrocortisone sodium succinate for injection, U.S.P.  相似文献   

18.
直接浸提-气相色谱法测定食品中的丙酸钙   总被引:2,自引:0,他引:2  
依据丙酸钙溶于水的特性,使样品中的丙酸钙在酸性条件下转化成丙酸,经超声波水浴提取,收集后调节pH值,经气相色谱(GC)测定,外标法定量.方法的检出限为0.01 g/kg,加标回收率为87.4%-94.4%,测定结果的相对标准偏差为1.72%(n=6).该方法在国家标准检测方法的基础上进行了改进,使其在满足食品中丙酸钙检...  相似文献   

19.
以碲化镉量子点为荧光背景物质,建立了毛细管电泳-间接激光诱导荧光检测食品中对羟基苯甲酸丙酯、脱氢乙酸钠、山梨酸、苯甲酸和丙酸钠含量的方法,紫外吸收很弱的丙酸钠在本方法中显示为正峰,可被有效检出.研究了碲化镉量子点浓度、背景电解质浓度、pH值、分离电压对分析物峰高和迁移时间的影响.在最佳条件下,对羟基苯甲酸丙酯、脱氢乙酸钠、山梨酸、苯甲酸和丙酸钠在8.5 min内得到分离,检出限分别为0.21,0.32,0.50,0.30和0.36 mg/L,相对标准偏差分别为3.9%,2.1%,2.5%,1.9%和2.3%,平均加标回收率分别为96.8%,93.4%,96.3%,98.1%和99.1%.本方法的检出限及线性范围均优于文献报道结果,对食品中这5种防腐剂检测的结果与高效液相色谱法结果一致.  相似文献   

20.
An LC/MS/MS method was developed and validated for the simultaneous identification, confirmation, and quantification of 12 glucocorticoids in bovine milk. The method was validated in accordance with the criteria defined in Commission Decision 2002/657/EC. The developed method can detect and confirm the presence of dexamethasone, betamethasone, prednisolone, flumethasone, 6alpha-methylprednisolone, fluorometholone, triamcinolone acetonide, prednisone, cortisone, hydrocortisone, clobetasol propionate, and clobetasol butyrate in bovine milk. Milk samples are extracted with acetonitrile; sodium chloride is subsequently added to aid partition of the milk and acetonitrile mixture. The acetonitrile extract is then subjected to liquid-liquid purification by the addition of hexane. The purified extract is evaporated to dryness and reconstituted in a water-acetonitrile mixture, and determination is carried out by LC/MS/MS. The method permits analysis of up to 30 samples in 1 day.  相似文献   

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