Cloud point extraction coupled with HPLC-UV for the determination of phthalate esters in environmental water samples

A method based on cloud point extraction was developed to determine phthalate esters including di-ethyl-phthalate （DEP）, di- （2-ethylhexyl）-phthalate （DEHP） and di-cyclohexyl-phthalate （DCP） in environmental water samples using high-performance liquid chromatography separation and ultraviolet detection （HPLC-UV）. The non-ionic surfactant Triton X-114 was chosen as extraction solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na2SO4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, the method can achieve preconcentration factors of 35, 88, 111 and detection of limits of 2.0, 3.8, 1.0 ng/ml for DEP, DEHP and DCP in 10-ml water sample, respectively. The proposed method was successfully applied to the determination of trace amount of phathalate esters in effluent water of the wastewater treatment plant and the lixivium of plastic fragments.

Analysis of in vivo absorption of didanosine tablets in male adult dogs by HPLC

Didanosine is an effective antiviral drug in untreated and antiretroviral therapy-experienced patients with Human Immunodeficiency Virus (HIV). An automated system using on-line solid extraction and High Performance Liquid Chromatography (HPLC) with ultraviolet (UV) detection was developed and validated for pharmacokinetic analysis of didanosine in dog plasma. Modifications were introduced on a previous methodology for simultaneous analysis of antiretroviral drugs in human plasma. Extraction was carried out on C18 cartridges, with high extraction yield as stationary phase, whereas mobile phase consisted of a mixture of 0.02 M potassium phosphate buffer, acetonitrile (KH2PO4: acetonitrile: 96:4, v/v) and 0.5% (w/v) of heptane sulphonic acid. The pH was adjusted to 6.5 with triethylamine. All samples and standard solutions were chromatographed at 28 1C. For an isocratic run, the fiux was 1.0 mL/min, detection was at 250 nm and injected volume was 20 mL. The method was selective and linear for concentrations between 50 and 5000 ng/mL. Drug stability data ranged from 96% to 98%, and limit of quantification was 25 ng/mL. Extraction yield was up to 95%. Drug stability in dog plasma was kept frozen at 20 1C for one month after three freeze–thaw cycles, and for 24 h after processing in the auto sampler. Assay was successfully applied to measure didanosine concentrations in plasma dogs.

Rapid Analysis of Morusin from <i>Ramulus mori</i>by HPLC-DAD, Its Distribution <i>in Vivo</i>and Differentiation in the Cultivated Mulberry Species

The distribution and content differentiation of morusin in the cultivated species of mulberry by HPLC-DAD are described in this paper. The experimental results showed that morusin is present in all parts of the mulberry bush. The content of morusin was highest in root bark and second highest in branch bark. The difference in morusin content of 20 different species of cultivated mulberry branch bark was significant. The level of morusin was highest in the branch bark of cultivated mulberry No. 404, a tetraploid cultivar, and third in the Husang 32 cultivar of Morus multicaulis. The method used in this study for determining morusin content exhibited good repeatability (RSD 6.02%) and recovery (100.62%). Therefore, the results from this study provide reliable data, for research and development in the future, on the level and distribution of morusin in mulberry in general and the differences found between various cultivated mulberries in particular. Furthermore, the HPLC-DAD method to determine morusin content is fast and reliable and is applicable not only to mulberry bushes but also to other plants.

Response surface optimization of microwave-assisted extraction for HPLC-fluorescence determination of puerarin and daidzein in Radix Puerariae thomsonii

Microwave-assisted extraction was optimized with response surface methodology for HPLC-fluorescence determination of puerarin and daidzein in Radix Puerariae thomsonii.The optimized extraction procedure was achieved by soaking the sample with 70% methanol（1∶15,v/v）for 30 min,and then microwave irradiation for 11 min at a power of 600 W.Coupling the extraction process with HPLC-fluorescence presented good recovery,satisfactory precision,and good linear relation.Compared with a method from the Chinese Pharmacopoeia,the proposed method enables higher extraction efficiency and more accurate analytical results.It can be of potential value in quality assessment of Radix Puerariae thomsonii medicinal materials.

Solid phase extraction of methomyl and thiodicarb from environmental water with an activated carbon cartridge and their determination by HPLC

A solid phase extraction procedure of methomyl and thiodicarb from environmental water was presented. This method utilizes a 40—60 mesh activated carbon cartridge and high performance liquid chromatography (HPLC). The 40—60 mesh activated carbon works faster and yield higher adsorption efficiency. Detection limits of methomyl and thiodicarb in environmental water are 0 1 μg/L and 0 2 μg/L, respectively. Average recoveries of fortified methomyl and thiodicarb in water are in the range of 90 7%—98 8% and 88 9%—103 6%, respectively. The relative standard deviations are lower than 7%. This method is simple, rapid, accurate and precise.

Determination of Triclocarban, Triclosan and Methyl-Triclosan in Environmental Water by Silicon Dioxide/Polystyrene Composite Microspheres Solid-Phase Extraction Combined with HPLC-ESI-MS

This paper developed a sensitive and efficient analytical method for triclocarban (TCC), triclosan (TCS) and Methyl-triclosan (MTCS) determination in environmental water, which involves enrichment by using silicon dioxide/polystyrene composite microspheres solid-phase extraction and detection with HPLC-ESI-MS. The influence of several operational parameters, including the eluant and its volume, the flow rate and acidity of water sample were investigated and optimized. Under the optimum conditions, the limits of detection were 1.0 ng/L, 2.5 and 4.5 ng/L for TCC, TCS, and MTCS, respectively. The linearity of the method was observed in the range of 5-2000 ng/L, with correlation coefficients (r2) >.99. The spiked recoveries of TCC, TCS and MTCS in water sampleswereachieved in the range of 89.5% -96.8% with RSD below 5.7%. The proposed method has been successfully applied to analyze real water samples and satisfactory results were achieved.

尿液中硝基安定、氯硝基安定和氟硝基安定的SepPak HPLC分析

本文介绍了一种用SepPak固相萃取技术和HPLC同时检验尿液中的苯并二氮草类药物硝基安定、氯硝基安定和氟硝基安定的方法。使用的反相色谱柱为YMC A—303C_(18)柱,以乙腈—0.01M醋酸铵(45:55,V/V)为流动相,紫外检测波长为254nm。各药物的回收率均大于80％;日内和日间测定的变异系数为1—5％。

Effect of Ultrasonic Treatment on the Extracting Activity of Kid Rennet

Using 2-3 weeks kid abomasums as materials, the ultrasound intensity, extracting time, NaCl concentration and pH valuein extracting solution and ratio of abomasums to extracting solution were studied by ultrasonic method. The resultsshowed that the main factor affecting kid rennet activity during extraction was ultrasound intensity, and then NaClconcentration, extracting time and ratio of abomasums to extracting solution in order. Kid rennet activity reached peakwith ultrasound intensity 30 W cm-2, extraction time 40 min, NaCl concentration 8%, pH value 3.0, ratio of abomasums toextracting solution 1:15.

Simultaneous Determination of Four Estrogens in Compost Based on Ultrasonic Solvent Extraction, Solid-Phase Extraction Clean-Up and Analysis by UHPLC-MS/MS

A rapid, cost effective and reliable analytical method was developed and validated for the simultaneous determination of four estrogens (17 β-estradiol, 17 α-ethinylestradiol, estrone, and estriol) in compost samples from the biodegradation of biological infectious hazardous wastes. Ultrasonic solvent extraction, using methanol as extraction solvent, coupled with SPE clean-up, using cartridges HLB 60 mg - 6 ml Supelco® and acetonitrile for reconstitution of eluents, was used for the simultaneous extraction of the four estrogens. Mean recoveries in the range of 98% - 107% were obtained. All compounds were separated in a single gradient run by UHPLC KinetexTM 2.6 μm XB-C18 100 ÅLC (50 × 4.6 mm) column. Analytes were detected via multiple reaction monitoring (MRM) using an AB SCIEX API-5000TM triple quadrupole (Applied Biosystems/MDS SCIEX) with electrospray ionization in negative mode. Isocratic mobile phase of Water:ACN (50:50) resulted to be the optimum. Limits of detection and quantification were on the order of 0.66 ng·g-1 and 2 ng·g-1 for all the estrogens. These limits were lower than most of the values reported in the literature for similar matrices. Suitable level of linearity, good repeatability and reproducibility with coefficients of variation is lower than 11.7%, 6.8% and 8.3%, respectively.

基于MSEP@CTAB的磁固相萃取结合HPLC-UV法测定环境水和饮品中的苏丹红

目的制备一种有机/无机双功能化磁性纳米复合材料MSEP@CTAB,将其作为磁固相萃取的吸附剂并结合HPLC-UV法检测环境水和饮品中的苏丹红残留。方法以Fe_(3)O_(4)作为磁性纳米粒子,选择海泡石(Sepiolite,SEP)为无机材料对其进行修饰,再采用十六烷基三甲基溴化铵(cetyltrimethylammonium bromide,CTAB)进行有机改性,得到有机/无机双功能化磁性纳米复合材料MSEP@CTAB;利用傅里叶变换红外光谱仪、透射电子显微镜、X射线衍射仪、振动样品磁力针和全自动比表面及孔隙度分析仪等对复合材料进行表征;考察并优化磁固相萃取条件。结果在最佳实验条件下,3种苏丹红染料在质量浓度0.5~50 ng·mL^(-1)内线性关系良好(R^(2)≥0.9962),检测限为0.05~0.07 ng·mL^(-1),定量限为0.17~0.23 ng·mL^(-1),日内和日间精密度分别为1.8%~8.8%和2.8%~9.0%。该方法被成功应用于环境水和饮品中3种苏丹红染料的检测,加标回收率为82.5%~108.2%。结论所建立的方法简便、快速、灵敏,为环境水和饮品中痕量苏丹红染料的检测提供了一种可行的策略。

饲料添加剂杜仲叶提取物HPLC特征图谱研究

研究旨在运用高效液相色谱法(HPLC)建立饲料添加剂杜仲叶提取物的特征图谱,为其质量控制提供参考。HPLC法采用Sunfire C18(4.6 mm×250 mm,5μm)色谱柱,以乙腈-0.1%甲酸水为流动相,流速为1.2 mL/min,进样量10μL,柱温35℃,检测波长254 nm,测定36批杜仲叶提取物的化学成分。选取36批杜仲叶提取物色图谱中分离度、峰型较好的8个峰为特征峰,得到杜仲叶提取物的HPLC特征图谱,根据对照品、精确相对分子质量、碎片离子等信息,鉴定出杜仲叶提取物中8个特征峰成分。结果表明,试验建立的杜仲叶提取物HPLC特征图谱共确定了8个特征峰,指认了桃叶珊瑚苷、京尼平苷酸、新绿原酸、绿原酸、隐绿原酸、芦丁、异槲皮苷7个色谱峰。研究表明,试验建立的杜仲叶提取物特征图谱实现了对其质量的稳定控制,可为杜仲叶提取物作为饲料添加剂的质量评价提供参考。

迷迭香提取物HPLC特征图谱研究

研究旨在运用高效液相色谱法(HPLC)建立饲用植物迷迭香提取物的特征图谱,为迷迭香提取物的辨别和质量控制提供新的方法。采用Sunfire C18色谱柱,以乙腈-0.1%甲酸水为流动相,以1.0 mL/min的流速、10µL的样品进样量、25℃的柱温、280 nm的紫外吸收波长作为液相色谱条件进行检测。结果显示:试验选取的15批迷迭香提取物色图谱中分离度、峰型较好的8个峰为特征峰,指认了迷迭香酸、鼠尾草酸、鼠尾草酚3个色谱峰,建立了迷迭香提取物的HPLC特征图谱。试验所建立的迷迭香提取物特征图谱实现了对其质量的稳定控制,可为迷迭香提取物质量评价提供参考。

Study on Extraction of Oolong Tea Assisted by Ultrasonic Wave and 4C Technique and Its Application

[Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea extract in cigarettes was studied.[Results]①In the experimental range,the best sensory evaluation effect of formula oolong tea extract was obtained with extraction conditions of 70%ethanol as extraction solvent,extraction time h,extraction temperature 25℃,and ultrasonic frequency 80 kHz,and follow-up low-temperature concentration,low-temperature sedimentation and low-temperature centrifugation.②The effects of different centrifugal speeds on the quality of formula oolong tea extract were explored.The formula oolong tea extract obtained under the conditions of 3000 r/min and centrifugal time of 10 min showed the best evaluation effect with soft and delicate smoke,rich smoke fragrance,good comfort and refreshing mouthfeel.③The effective aroma components in the formula oolong tea extract were qualitatively analyzed by GC-MS.[Conclusions]This study provides high-quality raw materials and a theoretical basis for the research of independent flavor blending in cigarette industry enterprises.

Ultrasonic-Assisted Extraction of Fucoxanthin from Marine Macroalga Padina australis:Optimization,Bioactivity,and Structural Characterization

Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the carotenoid family,fucoxanthin plays a crucial role in both the food and pharmaceutical industries.This research explores the effects of ultrasonics on the extraction of fucoxanthin from the marine macroalga Padina australis.In addition,various extraction techniques and the influence of solvents on the efficient separation of fucoxanthin from algae have been studied and compared.Using methanol,chloroform,and a combination of methanol and chloroform(1:1,v/v),conventional fucoxanthin extraction from Padina australis yielded 8.12 mg of fucoxanthin per gram of biomass.However,the ultrasonic-assisted extraction resulted in a significantly higher yield of 16.9 mg of fucoxanthin per gram of biomass,demonstrating that the use of ultrasonics enhances the extraction rate compared to conventional methods.Therefore,the efficient separation of fucoxanthin from Padina australis is highly dependent on ultrasonic-assisted extraction.The process conditions for the extraction were optimized to maximize the yield of fucoxanthin from seaweeds.The following parameters were selected for optimization studies:moisture content,particle size,mixing speed,extraction temperature,extraction duration,and solid-to-solvent ratio.The extracted fucoxanthin exhibited various biological activities,including antimicrobial and antioxidant properties,and its structure was elucidated through FTIR and NMR spectroscopy.Additionally,thin-layer chromatography of the crude algae extracts confirmed the presence of fucoxanthin in the marine algae.Given these findings,the optimized extraction process holds the potential for scaling up to large-scale fucoxanthin production.Fucoxanthin,as a potent pharmacological agent,offers promising applications in the treatment of various ailments.

HPLC-HRMS结合多元统计分析不同提取方法槐米提取物中黄酮类差异性成分

考察加热回流和超声辅助提取的槐米中黄酮类化合物的成分和含量差异。利用高效液相色谱-高分辨质谱(high performance liquid chromatography-high resolution mass spectrometry,HPLC-HRMS)技术建立芦丁、烟花苷、水仙苷和槲皮素等4种黄酮类化合物的定性与定量分析方法。以4种化合物的绝对含量为指标优化提取条件,建立优化的加热回流和超声辅助提取方法。采用主成分分析和偏最小二乘-判别分析比较两种方法提取物之间的成分差异。结果显示,4种化合物具有不同的最优提取条件,加热回流和超声辅助提取的4种化合物总含量分别为245.82 mg/g和303.34 mg/g,其中加热回流适合提取槐米中烟花苷和水仙苷,超声辅助适合提取芦丁和槲皮素。两种方法的提取物中23种成分存在显著性差异,鉴定了其中9个差异化合物。研究结果明确了槐米提取物在两种常用提取方法下的差异性,为槐米中黄酮类成分的高效提取提供了有益参考。

Analysis of Ultrasonic Emulsification Surgery and Small Incision Cataract Extracapsular Extraction Surgery for Cataract Clinical Treatment Level Improvement

Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected and randomly grouped into group A(ultrasonic emulsification)and group B(small-incision extracapsular cataract extraction),with 48 cases each.Results:At 1 week,1-month,and 3 months post-operation,the visual acuity of group A was higher and the astigmatism value was lower than that of group B(P<0.05);at 12h,24h,and 48h post-operation,the intraocular pressure of group A was higher than that of group B(P<0.05);the thickness of macular area of group A was lower than that of group B at 1 week and 1-month post-operation(P<0.05).Conclusion:Ultrasonic emulsification in cataract patients was slightly better than small incision cataract extracapsular extraction in correcting astigmatism,improving visual acuity,and regulating macular thickness.However,due to the high energy of ultrasonic emulsification,the risk of complications such as high postoperative intraocular pressure was higher.Small-incision extracapsular cataract extraction has better application value in economically disadvantaged areas.

固相萃取-HPLC-ESI-MS/MS法测定水中全氟化合物

搭建了固相萃取-超高效液相色谱-电喷雾-串联质谱仪,发现测定水中17种全氟化合物(PFCs)的检测方法。采用玻璃纤维滤膜过滤样品,WAX萃取柱(固相萃取小柱)对样品进行前处理后,柱温和流速分别设定为40℃和0.3 mL/min,使用乙酸铵和乙腈作为流动相,利用梯度洗脱程序进行分离,超高效液相色谱-串联质谱多反应监测(MRM)负离子模式测定,内标法定量。通过优化实验的样品前处理条件和测试参数,标准曲线绘制结果显示,在0~100μg/L范围内,17种全氟化合物线性良好(R大于0.999)。低、中、高3种质量浓度的实际加标样品的相对标准偏差在0.53%~12.00%,回收率在70.7%~114.0%。测试结果表明该方法可以应用于实际检测工作。

HPLC法同时测定健腰密骨片浸膏粉中5种指标成分

目的:建立健腰密骨片浸膏粉的多成分定量分析方法,为评价浸膏粉中间体的质量提供依据。方法:采用HPLC法,以乙腈-磷酸盐缓冲液为流动相,梯度洗脱,测定健腰密骨片浸膏粉中5种成分的含量。结果:木兰花碱、丹酚酸B、朝藿定C、淫羊藿苷和宝藿苷Ⅰ5种成分在各自质量浓度范围内呈良好线性关系,r≥0.9997;5种化合物的平均回收率分别为100.47%、104.37%、95.38%、95.93%、96.66%。该方法的专属性、重复性均良好。结论:该分析方法准确、重复性好,可作为健腰密骨片浸膏粉的质量控制方法。

HPLC法测定杜仲叶提取物中京尼平苷酸、绿原酸、京尼平苷、芦丁含量

研究旨在建立高效液相色谱法同时测定杜仲叶提取物中尼平苷酸、绿原酸、京尼平苷、芦丁含量的方法。试验选择Agilent ZORBAX SB-C18色谱柱,以乙腈-0.4%磷酸溶液为流动相,流速1.0 mL/min,柱温30℃,进样量10μL,波长235 nm。结果显示:4种成分在检测范围中所呈现出的线性关系良好,平均加样回收率为100.8%~103.0%,相对标准偏差(RSD)为0.90%~2.37%。不同生产厂家的杜仲叶提取物中4种成分含量存在一定差异。研究表明,试验建立的方法操作简单、稳定可靠、重复性好,可以用于杜仲叶提取物的质量控制。

土家药刺老苞不同极性提取物的HPLC指纹图谱方法验证研究

目的建立一种可用于不同极性刺老苞提取物的高效液相色谱(HPLC)指纹图谱方法。方法采用HPLC法对色谱条件进行优化,并进行方法学验证。结果色谱条件为Agilent C_(18)(250 mm×4.6 mm,5μm)色谱柱,乙腈(A)-0.1%磷酸(B)流动相梯度洗脱,检测波长280 nm,柱温30℃,进样量10μL。方法学验证显示,该HPLC指纹图谱法精密度、稳定性、重复性的相对标准偏差(RSD)符合要求。结论该HPLC指纹图谱法可同时应用于刺老苞不同极性提取物的检验,可初步比较各提取物之间的差异。