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 sample...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®<sup></sup> 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 Kinetex<sup>TM</sup> 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<sup>-1</sup> and 2 ng·g<sup>-1</sup> 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.展开更多
A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitami...A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitamin functional drink. The analysis used a reversed-phase C18 column, with a photo-diode array detector at 220 nm. The samples were preconcentrated with packed-fiber solid-phase extraction columns. Good linearity was observed in vitamin functional drink. The repeatability of extraction performance, expressed as relative standard deviations, was from 3.5% to 4.3%. The limit of detection （LOD） is 5 ng mL^-1 （S/N = 3）. Finally, the method had been applied for the determination of vitamin B12 in vitamin functional drink.展开更多
A new method for simultaneous determination of four phthalate esters （ PAEs） in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas...A new method for simultaneous determination of four phthalate esters （ PAEs） in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas chromatography-flame ionization detector （ GC-FID ）. Conditions for obtaining optimum extraction efficiency such as extraction solvents, morphologies of adsorbent, ion strength and pH were investigated and optimized in detail. Under the optimized conditions, the limits of detection （LODs） found for dibutyl phthalate （DBP） , butyl benzyl phthalate （BBP）, diethyl hexyl phthalate （DEHP） and di-n-octyl phthalate （DNOP） were 50, 25, 50 and 25 ng/g, respectively. Good linearity of four PAEs was achieved in the range of 50 to 4 000 ng/g. The proposed method was applied for analyzing different kinds of fat-containing samples. PAEs in commercial fat-containing samples can be highly extracted by a packed solid-phase extraction column of 5 mg polystyrene （ PS） nanofibers. The satisfactory average recoveries were obtained in the range of 96. 7% to 102. 3% , and the relative standard deviations （RSDs） below 5% were achieved. The proposed method reduces the organic solvent consumption, the complex and tedious procedures for sample pretreatment, and achieves high sensitivity and reproducibility for the investigated PAEs.展开更多
Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitativ...Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance （HLB） cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 （pH 5.7） and methanol （98：2, v/v） at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses （150, 300 and 600 mg） of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use.展开更多
A new pre-column derivation HPLC method with solid-phase extraction to determine captopril in human plasma was established. Derivation products were extracted by a solid-phase extraction method after the reagent, p-a-...A new pre-column derivation HPLC method with solid-phase extraction to determine captopril in human plasma was established. Derivation products were extracted by a solid-phase extraction method after the reagent, p-a-dibromoacetophenone(p-BPB), was added in the plasma samples. The samples were analyzed in a VP-ODS column with UV-detector. The calibration curve of captopril was linear within the range of 5~1000 ngmL-1 with r=0.9987, the recovery of this method was 98.652.04%, within day and between day RSD were no more than 3.4% and 8.4% respectively. To study the pharmacokinetics and the relative bioavailability of captopril tablets, two formulations of captopril tablets were given to 18 healthy male volunteers according to a randomized 2-way cross-over design with a 1-week washout period. The respective AUC0~6 , Cmax and Tmax values of the two formulations were 424.5125.7 and 439.4113.3 mghL-1; 505.9244.6 and 504.8172.2 mgL-1; 0.6620.181 and 0.5280.176 h. Results from statistics analysis showed that there were no significant difference between the AUC0~6 , Cmax and Tmax values of the two formulations, The relative bioavailability of tablets I with respect to II was 96.114.6% from AUC0~6 measurement. Bioequivalance was observed between the two tablets.展开更多
This work describes a systematic approach to the development of a method for simultaneous determination of three classes of veterinary antibiotics in the suspended solids （SS） of swine wastewater, including five sul...This work describes a systematic approach to the development of a method for simultaneous determination of three classes of veterinary antibiotics in the suspended solids （SS） of swine wastewater, including five sulfonamides, three tetracyclines and one macrolide （tiamulin）. The entire procedures for sample pretreatment, ultrasonic extraction （USE）, solid-phase extraction （SPE）, and liquid chromatography-mass spectrometry （LC-MS） quantification were examined and optimized. The recovery efficiencies were found to be 76%-104% for sulfonamides, 81%-112% for tetracyclines, and 51%--64% for tiamulin at three spiking levels. The intra-day and inter-day precisions, as expressed by the relative standard deviation （RSD）, were below 17%. The method detection limits （MDLs） were between 0.14 and 7.14 μg/kg, depending on a specific antibiotic studied. The developed method was applied to field samples collected from three concentrated swine feeding plants located in Beijing, Shanghai and Shandong province of China. All the investigated antibiotics were detected in both SS and liquid phase of swine wastewater, with partition coefficients （logKd） ranging from 0.49 to 2.30. This study demonstrates that the SS can not be ignored when determining the concentrations of antibiotics in swine wastewater.展开更多
The volatile and semi-volatile components in tobacco flavor additives were extracted by both simultaneous distillation extraction and solid-phase micro-extraction. Extraction conditions for solid-phase micro-extractio...The volatile and semi-volatile components in tobacco flavor additives were extracted by both simultaneous distillation extraction and solid-phase micro-extraction. Extraction conditions for solid-phase micro-extraction were optimized with information theory. Then, detection were accomplished by gas chromatography-mass spectrometry. Characteristic of each method was compared. Qualitative analysis and quantitative analysis of 6# tobacco flavor sample were accomplished through both simultaneous distillation extraction and solid-phase micro-extraction. The experimental results show that solid-phase micro-extraction method is the first choice for qualitative analysis and simultaneous distillation extraction is another good selection for quantitative analysis. By means of simultaneous distillation extraction, 20 components are identified, accounting for 92.77% of the total peak areas. Through solid-phase micro-extraction, there are 17 components identified accounting for 91.49% of the total peak areas. The main aromatic components in 6# tobacco flavor sample are propanoic acid, 2-hydroxy-, ethyl ester, menthol and menthyl acetate. The presented method has been successfully used for quality control of tobacco flavor.展开更多
A fast analytical method for the simultaneous determination of 9 mycotoxins, including alfatoxins （B1, B2, G1, and G2）, fumonisins （B1, B2 and B3）, zearalenone, and deoxynivalenol in corn using dispersive solid-ph...A fast analytical method for the simultaneous determination of 9 mycotoxins, including alfatoxins （B1, B2, G1, and G2）, fumonisins （B1, B2 and B3）, zearalenone, and deoxynivalenol in corn using dispersive solid-phase extraction method and ultra-performance liquid chromatography coupled to tandem quadrupole time-of-lfight mass spectrometry （UPLC-Q-TOF-MS） was developed and validated. Samples were extracted with acetonitrile-water （84：16, v：v, containing 1% acetic acid） using ultrasonic extraction. The extracts were puriifed with a dispersive SPE method using C18 as a cleaning agent. The ifnal clear extracts were dried by nitrogen blowing and subsequently redissolved in methanol-water （5：5, v：v）. The samples were then analyzed by UPLC-Q-TOF-MS with 0.1% formic acid in ammonium acetate-methanol as mobile phase. The mean recoveries were ranged from 68.0 to 120.0%, and the relative standard deviation （RSD） ranged from 0.18 to 6.29%. Limits of detections ranged from 0.05 to 50 μg kg？1, and limits of quantiifcation ranged from 0.1 to 200 μg kg？1, which were below the legal limits set by the European Union for the legislated mycotoxins. The developed method was applied to 130 corn samples. Among the mycotoxins studied, alfatoxins B1 and fumonisins B1, B2 and B3 were the most predominant mycotoxins, and their concentrations were 0–593.12, 0–2.01×104, 0–6.94×103 and 0–3.05×103 μg kg–1, respectively.展开更多
A simple and efficient dithizone-functionalized solid-phase extraction(SPE)procedure,online coupled with high-performance liquid chromatography(HPLC)-inductively coupled plasma mass spectrometry,was developed for the ...A simple and efficient dithizone-functionalized solid-phase extraction(SPE)procedure,online coupled with high-performance liquid chromatography(HPLC)-inductively coupled plasma mass spectrometry,was developed for the first time for enrichment and determination of ultra-trace mercury(Hg)species(inorganic divalent Hg(Hg(Ⅱ)),methylmercury(CH_(3)Hg(Ⅱ))and ethylmercury(C_(2)H_(5)Hg(Ⅱ))in cereals and environmental samples.In the proposed method,functionalization of the commercial C_(18) column with dithizone,enrichment,and elution of the above Hg species can be completed online with the developed SPE device.A simple solution of 2-mercaptoethanol(1%(V/V))could be used as an eluent for both the SPE and HPLC separation of Hg species,significantly simplifying the method and instrumen-tation.The online SPE method was optimized by varying dithizone dose,2-mercaptoethanol concentration,and sample volume.In addition,the effect of pH,coexisting interfering ions,and salt effect on the enrichment was also discussed.Under the optimized conditions,the detection limits of Hg species for 5 mL water sample were 0.15 ng/L for Hg(Ⅱ),0.07 ng/L for CH_(3)Hg(Ⅱ),and 0.04 ng/L for C_(2)H_(5)Hg(Ⅱ)with recoveries in the range of 85%-100%.The developed dithizone-functionalized C_(18) SPE column can be reused after a single function-alization,which significantly simplifies the enrichment step.Moreover,the stability of Hg species enriched on the SPE column demonstrated its suitability for field sampling of Hg species for later laboratory analysis.This environment-friendly method offers a robust tool to detect ultra-trace Hg species in cereals and environmental samples.展开更多
A solid-phase extraction resin SIRs-P227/XAD-7 HP was prepared by impregnating extractant P227 onto macroporous resin XAD-7 HP beads. SIRs-P227/XAD-7 HP beads were characterized by Fourier transform infrared spectrosc...A solid-phase extraction resin SIRs-P227/XAD-7 HP was prepared by impregnating extractant P227 onto macroporous resin XAD-7 HP beads. SIRs-P227/XAD-7 HP beads were characterized by Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM) equipped with energy-dispersive spectroscopy(EDS). The adsorption kinetics, particle size effect,adsorption isotherm, pH_(equilibrium)–lg D relationship(where D is distribution coefficient), desorption, adsorption selectivity for heavy rare earths, and impurity ions were studied. The results showed that the adsorption kinetics of Lu(III) on the SIRs-P227/XAD-7 HP beads fitted the Morris–Weber model best. The adsorbance decreased as the particle size increased. The pH_(equilibrium)–lg D relationship fitted well with a straight line, and the slope was 1.56. The experimental data fitted well with Langmuir adsorption.The calculated maximum adsorption capacity was23.8 mg·g^(-1), while the experimental datum was22.7 mg·g^(-1) at the given conditions. The adsorbed Lu(III)can be easily stripped by 0.1 mol·L^(-1) HCl. The adsorption selectivity of SIRs-P227/XAD-7 HP for heavy REs exhibited the following order: Lu>Yb>Tm>Er>Ho. The adjacent heavy rare earth(RE) separation factors β_(Lu/Yb),β_(Yb/Tm), β_(Tm/Er), and β_(Er/Ho)were 1.57, 3.00, 3.03, and 2.23,respectively, at liquid/solid ratio(L/S) equal to 3:20. The adsorption selectivity for impurity ions exhibited the followingorder:Fe >Lu>Tm>Zn>Mg>Ca>Ho>Co>Ni>Cu>Al.展开更多
A method for the simultaneous separation and determination of organic acids and inorganic anions in Bayer liquors was developed by gradient ion chromatography with suppressed conductivity detection. Formate, acetate, ...A method for the simultaneous separation and determination of organic acids and inorganic anions in Bayer liquors was developed by gradient ion chromatography with suppressed conductivity detection. Formate, acetate, propionate, oxalate, succinate, glutarate, fluoride, chloride and sulfate were separated and determined in 33 min. The samples were pretreated with solid-phase extraction, which has high selectivity for removing a large number of metallic ions in the Bayer liquors, and filtered with a 0.45 μm filter membrane before being injected into the ion chromatographic system. The separation of six organic acids and three inorganic anions was achieved on an IonPac AS11-HC column with KOH as the eluent, and the detection was performed by a conductivity detection mode. No interference is found in the presence of fluorate, chlorate and sulphate when organic acids are determined. The calibration graphs of peak area for all the analytes are linear over a wide range. The relative standard derivation of the peak area of analytes is less than 2.14%. Under optimum conditions the detection ranges from 0.2 to 100.0 mg/L. The average recoveries of the added standards are between 94.3% and 102.8%.展开更多
The new catalytic kinetic spectrophotometric method for Au（III） determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate ...The new catalytic kinetic spectrophotometric method for Au（III） determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate （（NH4）2S2O8） with nitrilo triacetic acid as an activator in microemulsion and H2SO4 medium. Under optimum conditions, there was the linearity of the calibration curve in the concentration range from 0 to 20 μg/L Au（Ⅲ） at 520 nm. The relative standard deviation was 3.0% with a correlation coefficient of 0.9986. The detection limit achieved was 9.75 × 10^-5 μg/mL. A new method using a column packed with sulfhydryl dextrose gel （SDG） as a solid-phase extractant has been developed for the preconcentration and separation of Au（Ⅲ） ions. The method has been applied to the determination of trace gold with satisfactory results.展开更多
A new analytical procedure based on solid-phase extraction method coupled to GC-FID has been developed and validated for the determination of five phthalate esters （PAEs） （dimethyl-（DMP）, diethyl-（DEP）, di-n-bu...A new analytical procedure based on solid-phase extraction method coupled to GC-FID has been developed and validated for the determination of five phthalate esters （PAEs） （dimethyl-（DMP）, diethyl-（DEP）, di-n-butyl-（DBP）, di-2-ethylhexyl- （DEHP）, di-n-octyl-（DOP）） in fish samples. There was a good linear relationship in the range of 0.05-10μg with the detection limits of 0.09-0.16ng .The recoveries obtained for PAEs ranged from 88.6% to 96.4%with RSD of 4.2%-10.2%.The applicability of the developed method was demonstrated for real fish samples.展开更多
A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 a...A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 and Oasis HLB. Parameters that influence the extraction efficiency such as the eluent volume, the sample loading volume, the addition of organic solvent to water sample, sorbent drying and elute concentration were optimized. The innovation of this work was the examination of the use of a centrifugation technique in both the drying and elution steps. When combined with centrifugation, the volume of the elution solvent was reduced to 2 mL and the time for sorbent drying decreased also to 10 min under vacuum. Under the optimized conditions, this method showed good recoveries higher than 65% - 68% for the 67 analyzed pesticides using the C18 and HLB cartridges with relative standard deviations lower than 9.7% - 12.3%. Limits of quantification were between 2 and 20 ng.L–1. The simplicity of the described method, use of less of organic solvent, short procedure time, and good recoveries demonstrate the advantages of this environmentally friendly approach for routine analysis of numerous samples.展开更多
Enrichment of trace bioactive constituents and metabolites from complex biological samples is challenging.This study presented a one-pot synthesis of magnetic polydopamine nanoparticles(Fe3O4@-SiO2@PDA NPs)with multip...Enrichment of trace bioactive constituents and metabolites from complex biological samples is challenging.This study presented a one-pot synthesis of magnetic polydopamine nanoparticles(Fe3O4@-SiO2@PDA NPs)with multiple recognition sites for the magnetic dispersive solid-phase extraction(MDSPE)of ginsenosides from rat plasma treated with white ginseng.The extracted ginsenosides were characterized by combining an ultra-high-performance liquid chromatography coupled to a highresolution mass spectrometry with supplemental UNIFI libraries.Response surface methodology was statistically used to optimize the extraction procedure of the ginsenosides.The reusability of Fe3O4@-SiO2@PDA NPs was also examined and the results showed that the recovery rate exceeded 80%after recycling 6 times.Furthermore,the proposed method showed greater enrichment efficiency and could rapidly determine and characterize 23 ginsenoside prototypes and metabolites from plasma.In comparison,conventional methanol method can only detect 8 ginsenosides from the same plasma samples.The proposed approach can provide methodological reference for the trace determination and characterization of different bioactive ingredients and metabolites of traditional Chinese medicines and food.展开更多
Liquid-liquid extraction-thin layer chromatography （LLE-TLC） has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction （SPE） is gradually replacing the tr...Liquid-liquid extraction-thin layer chromatography （LLE-TLC） has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction （SPE） is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography （HPTLC） has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, ＇were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories.展开更多
Improved analytical methods for the metabolomic profiling of tissue samples are constantly needed.Currently,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the ...Improved analytical methods for the metabolomic profiling of tissue samples are constantly needed.Currently,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the endogenous metabolome.In this study,solid-phase microextraction(SPME)fibers were used to monitor changes in endogenous compounds in homogenized and intact ovine lung tissue.Following SPME,a Biocrates AbsoluteIDQ assay was applied to make a downstream targeted metabolomics analysis and confirm the advantages of in vivo SPME metabolomics.The AbsoluteIDQ kit enabled the targeted analysis of over 100 metabolites via solid-liquid extraction and SPME.Statistical analysis revealed significant differences between conventional liquid extractions from homogenized tissue and SPME results for both homogenized and intact tissue samples.In addition,principal component analysis revealed separated clustering among all the three sample groups,indicating changes in the metabolome due to tissue homogenization and the chosen sample preparation method.Furthermore,clear differences in free metabolites were observed when extractions were performed on the intact and homogenized tissue using identical SPME procedures.Specifically,a direct comparison showed that 47 statistically distinct metabolites were detected between the homogenized and intact lung tissue samples(P<0.05)using mixed-mode SPME fibers.These changes were probably due to the disruptive homogenization of the tissue.This study's findings highlight both the importance of sample preparation in tissue-based metabolomics studies and SPME's unique ability to perform minimally invasive extractions without tissue biopsy or homogenization while providing broad metabolite coverage.展开更多
The solid-phase extraction（SPE） technique applied to the extraction of organic compound was creatively used as the extraction of inorganic gold in the paper.Two types of techniques were proposed and explored,namely ...The solid-phase extraction（SPE） technique applied to the extraction of organic compound was creatively used as the extraction of inorganic gold in the paper.Two types of techniques were proposed and explored,namely the SPE and the liquid–liquid extraction（LLE） of the quaternary ammonium surfactant [cetytrimethyl ammonium bromide（CTMAB）,cetyl pyridine bromide（CPB）,benzyl dimethyl dodecyl ammonium chloride（BDMDAC）,and dodecyl trimethyl ammonium chloride（DTMAC）].The surfactant could react with Au（CN）2^- to form the ionic complex,and the compound could be extracted by SPE column of reversed-phase bonded silica gel.Hence,a new method of SPE was proposed to extract gold with these features of the high selectivity,the reliability,and the simplicity.The experimental result shows that the recovery rate of gold is more than 98 %,and the solid-phase extraction column is not easily damaged and it can be repeatedly used.The new method can be used as the extraction process of gold from alkaline cyanide solution as well.Besides,the paper also puts forward a new process of gold extraction.展开更多
In this work, a metal-organic framework derived nanoporous carbon （MOF-5-C） was fabricated and modified with Fe3O4 magnetic nanoparticles. The resulting magnetic MOF-5-derived porous carbon （Fe304@MOF-5-C） was the...In this work, a metal-organic framework derived nanoporous carbon （MOF-5-C） was fabricated and modified with Fe3O4 magnetic nanoparticles. The resulting magnetic MOF-5-derived porous carbon （Fe304@MOF-5-C） was then used for the magnetic solid-phase extraction of chlorophenols （CPs） from mushroom samples prior to high performance liquid chromatography-ultraviolet detection. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and N2 adsorption were used to characterize the adsorbent. After experimental optimization, the amount of the adsorbent was chosen as 8.0 mg, extraction time as 10 min, sample volume as 50 mL, desorption solvent as 0.4 mL （0.2 mL × 2） of alkaline methanol, and sample pH as 6. Under the above optimized conditions, good linearity for the analytes was obtained in the range of 0.8-100.0 ng g 1 with the correlation coefficients between 0.9923 and 0.9963. The limits of detection （SIN= 3） were in the range of 0.25-0.30 ng g-1, and the relative standard deviations were below 6.8%. The result showed that the Fe304@MOF-5-C has an excellent adsorption capacity for the analytes.展开更多
In this paper, a method was established to determine the boiling point distribution of hydrocarbon types in diesel. The diesel sample was separated into the saturate and aromatic fractions by means of solid-phase extr...In this paper, a method was established to determine the boiling point distribution of hydrocarbon types in diesel. The diesel sample was separated into the saturate and aromatic fractions by means of solid-phase extraction （SPE）, and each fraction was analyzed by GC/FID-EIMS. According to the relationship between boiling point and retention time of n-paraffins in the chromatogram, the percentages of saturates and aromatics at each temperature interval were calculated. According to the average mass spectra of the saturate and aromatic fractions at each temperature interval, the hydrocarbon types of the sample were identified through summation of characteristic mass fragments. Using this method, the changes in composition of diesel during hydrotreating process were studied. The results showed that hydrogenation of aromatics is the main reaction during the hydrotreating process. The more rings the aromatics have, the easier the hydrogenation reactions would take place. The aromatics were converted into cycloparaffins via the hydrogenation and saturation process, leading to an increase in low boiling point fractions in the hydrotreated oil.展开更多
文摘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®<sup></sup> 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 Kinetex<sup>TM</sup> 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<sup>-1</sup> and 2 ng·g<sup>-1</sup> 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.
基金supported by Jiangsu Science and Technology Department(No.BG2007044)Jiangsu Preventive Medicine Foundation(No.Y2006025).
文摘A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitamin functional drink. The analysis used a reversed-phase C18 column, with a photo-diode array detector at 220 nm. The samples were preconcentrated with packed-fiber solid-phase extraction columns. Good linearity was observed in vitamin functional drink. The repeatability of extraction performance, expressed as relative standard deviations, was from 3.5% to 4.3%. The limit of detection （LOD） is 5 ng mL^-1 （S/N = 3）. Finally, the method had been applied for the determination of vitamin B12 in vitamin functional drink.
基金The National Basic Research Program of China(973Program)(No.2012CB933302)the National Instrumental Research Program(No.2014YQ06077303)+1 种基金the National Natural Science Foundation of China(No.81172720,21307086)Suzhou Science and Technology Department Foundation(No.ZXG201441)
文摘A new method for simultaneous determination of four phthalate esters （ PAEs） in commercial fat-containing foods was developed by the combination of a packed nanofibers column based on solid-phase extraction with gas chromatography-flame ionization detector （ GC-FID ）. Conditions for obtaining optimum extraction efficiency such as extraction solvents, morphologies of adsorbent, ion strength and pH were investigated and optimized in detail. Under the optimized conditions, the limits of detection （LODs） found for dibutyl phthalate （DBP） , butyl benzyl phthalate （BBP）, diethyl hexyl phthalate （DEHP） and di-n-octyl phthalate （DNOP） were 50, 25, 50 and 25 ng/g, respectively. Good linearity of four PAEs was achieved in the range of 50 to 4 000 ng/g. The proposed method was applied for analyzing different kinds of fat-containing samples. PAEs in commercial fat-containing samples can be highly extracted by a packed solid-phase extraction column of 5 mg polystyrene （ PS） nanofibers. The satisfactory average recoveries were obtained in the range of 96. 7% to 102. 3% , and the relative standard deviations （RSDs） below 5% were achieved. The proposed method reduces the organic solvent consumption, the complex and tedious procedures for sample pretreatment, and achieves high sensitivity and reproducibility for the investigated PAEs.
基金National Natural Science Foundation of China (Grant No.30973597)
文摘Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance （HLB） cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 （pH 5.7） and methanol （98：2, v/v） at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses （150, 300 and 600 mg） of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use.
文摘A new pre-column derivation HPLC method with solid-phase extraction to determine captopril in human plasma was established. Derivation products were extracted by a solid-phase extraction method after the reagent, p-a-dibromoacetophenone(p-BPB), was added in the plasma samples. The samples were analyzed in a VP-ODS column with UV-detector. The calibration curve of captopril was linear within the range of 5~1000 ngmL-1 with r=0.9987, the recovery of this method was 98.652.04%, within day and between day RSD were no more than 3.4% and 8.4% respectively. To study the pharmacokinetics and the relative bioavailability of captopril tablets, two formulations of captopril tablets were given to 18 healthy male volunteers according to a randomized 2-way cross-over design with a 1-week washout period. The respective AUC0~6 , Cmax and Tmax values of the two formulations were 424.5125.7 and 439.4113.3 mghL-1; 505.9244.6 and 504.8172.2 mgL-1; 0.6620.181 and 0.5280.176 h. Results from statistics analysis showed that there were no significant difference between the AUC0~6 , Cmax and Tmax values of the two formulations, The relative bioavailability of tablets I with respect to II was 96.114.6% from AUC0~6 measurement. Bioequivalance was observed between the two tablets.
基金supported by the National Natural Science Foundation of China (No. 50878206, 50921064)the Ministry of Science and Technology of China (No. 2007AA06Z344,2009BAC57B02, 2009AA063901)
文摘This work describes a systematic approach to the development of a method for simultaneous determination of three classes of veterinary antibiotics in the suspended solids （SS） of swine wastewater, including five sulfonamides, three tetracyclines and one macrolide （tiamulin）. The entire procedures for sample pretreatment, ultrasonic extraction （USE）, solid-phase extraction （SPE）, and liquid chromatography-mass spectrometry （LC-MS） quantification were examined and optimized. The recovery efficiencies were found to be 76%-104% for sulfonamides, 81%-112% for tetracyclines, and 51%--64% for tiamulin at three spiking levels. The intra-day and inter-day precisions, as expressed by the relative standard deviation （RSD）, were below 17%. The method detection limits （MDLs） were between 0.14 and 7.14 μg/kg, depending on a specific antibiotic studied. The developed method was applied to field samples collected from three concentrated swine feeding plants located in Beijing, Shanghai and Shandong province of China. All the investigated antibiotics were detected in both SS and liquid phase of swine wastewater, with partition coefficients （logKd） ranging from 0.49 to 2.30. This study demonstrates that the SS can not be ignored when determining the concentrations of antibiotics in swine wastewater.
文摘The volatile and semi-volatile components in tobacco flavor additives were extracted by both simultaneous distillation extraction and solid-phase micro-extraction. Extraction conditions for solid-phase micro-extraction were optimized with information theory. Then, detection were accomplished by gas chromatography-mass spectrometry. Characteristic of each method was compared. Qualitative analysis and quantitative analysis of 6# tobacco flavor sample were accomplished through both simultaneous distillation extraction and solid-phase micro-extraction. The experimental results show that solid-phase micro-extraction method is the first choice for qualitative analysis and simultaneous distillation extraction is another good selection for quantitative analysis. By means of simultaneous distillation extraction, 20 components are identified, accounting for 92.77% of the total peak areas. Through solid-phase micro-extraction, there are 17 components identified accounting for 91.49% of the total peak areas. The main aromatic components in 6# tobacco flavor sample are propanoic acid, 2-hydroxy-, ethyl ester, menthol and menthyl acetate. The presented method has been successfully used for quality control of tobacco flavor.
基金supported by the Key Project of Science and Technology Development Program of Shandong Province,China(2013KF03)
文摘A fast analytical method for the simultaneous determination of 9 mycotoxins, including alfatoxins （B1, B2, G1, and G2）, fumonisins （B1, B2 and B3）, zearalenone, and deoxynivalenol in corn using dispersive solid-phase extraction method and ultra-performance liquid chromatography coupled to tandem quadrupole time-of-lfight mass spectrometry （UPLC-Q-TOF-MS） was developed and validated. Samples were extracted with acetonitrile-water （84：16, v：v, containing 1% acetic acid） using ultrasonic extraction. The extracts were puriifed with a dispersive SPE method using C18 as a cleaning agent. The ifnal clear extracts were dried by nitrogen blowing and subsequently redissolved in methanol-water （5：5, v：v）. The samples were then analyzed by UPLC-Q-TOF-MS with 0.1% formic acid in ammonium acetate-methanol as mobile phase. The mean recoveries were ranged from 68.0 to 120.0%, and the relative standard deviation （RSD） ranged from 0.18 to 6.29%. Limits of detections ranged from 0.05 to 50 μg kg？1, and limits of quantiifcation ranged from 0.1 to 200 μg kg？1, which were below the legal limits set by the European Union for the legislated mycotoxins. The developed method was applied to 130 corn samples. Among the mycotoxins studied, alfatoxins B1 and fumonisins B1, B2 and B3 were the most predominant mycotoxins, and their concentrations were 0–593.12, 0–2.01×104, 0–6.94×103 and 0–3.05×103 μg kg–1, respectively.
基金This work was supported by the National Key Research and Development Project(No.2020YFA0907400)the National Natural Science Foundation of China(Nos.21777178,21976193)+1 种基金Y.Yin acknowledges the supports from the National Young Top-Notch Talents(No.W03070030)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y202011).
文摘A simple and efficient dithizone-functionalized solid-phase extraction(SPE)procedure,online coupled with high-performance liquid chromatography(HPLC)-inductively coupled plasma mass spectrometry,was developed for the first time for enrichment and determination of ultra-trace mercury(Hg)species(inorganic divalent Hg(Hg(Ⅱ)),methylmercury(CH_(3)Hg(Ⅱ))and ethylmercury(C_(2)H_(5)Hg(Ⅱ))in cereals and environmental samples.In the proposed method,functionalization of the commercial C_(18) column with dithizone,enrichment,and elution of the above Hg species can be completed online with the developed SPE device.A simple solution of 2-mercaptoethanol(1%(V/V))could be used as an eluent for both the SPE and HPLC separation of Hg species,significantly simplifying the method and instrumen-tation.The online SPE method was optimized by varying dithizone dose,2-mercaptoethanol concentration,and sample volume.In addition,the effect of pH,coexisting interfering ions,and salt effect on the enrichment was also discussed.Under the optimized conditions,the detection limits of Hg species for 5 mL water sample were 0.15 ng/L for Hg(Ⅱ),0.07 ng/L for CH_(3)Hg(Ⅱ),and 0.04 ng/L for C_(2)H_(5)Hg(Ⅱ)with recoveries in the range of 85%-100%.The developed dithizone-functionalized C_(18) SPE column can be reused after a single function-alization,which significantly simplifies the enrichment step.Moreover,the stability of Hg species enriched on the SPE column demonstrated its suitability for field sampling of Hg species for later laboratory analysis.This environment-friendly method offers a robust tool to detect ultra-trace Hg species in cereals and environmental samples.
基金financially supported by the National Natural Science Foundation of China(Nos.51974026 and 21301104)the National Key R&D Program of China(No.2018YFC1900604)the Fundamental Research Funds for the Central Universities(No.FRF-TP-16019A3)。
文摘A solid-phase extraction resin SIRs-P227/XAD-7 HP was prepared by impregnating extractant P227 onto macroporous resin XAD-7 HP beads. SIRs-P227/XAD-7 HP beads were characterized by Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM) equipped with energy-dispersive spectroscopy(EDS). The adsorption kinetics, particle size effect,adsorption isotherm, pH_(equilibrium)–lg D relationship(where D is distribution coefficient), desorption, adsorption selectivity for heavy rare earths, and impurity ions were studied. The results showed that the adsorption kinetics of Lu(III) on the SIRs-P227/XAD-7 HP beads fitted the Morris–Weber model best. The adsorbance decreased as the particle size increased. The pH_(equilibrium)–lg D relationship fitted well with a straight line, and the slope was 1.56. The experimental data fitted well with Langmuir adsorption.The calculated maximum adsorption capacity was23.8 mg·g^(-1), while the experimental datum was22.7 mg·g^(-1) at the given conditions. The adsorbed Lu(III)can be easily stripped by 0.1 mol·L^(-1) HCl. The adsorption selectivity of SIRs-P227/XAD-7 HP for heavy REs exhibited the following order: Lu>Yb>Tm>Er>Ho. The adjacent heavy rare earth(RE) separation factors β_(Lu/Yb),β_(Yb/Tm), β_(Tm/Er), and β_(Er/Ho)were 1.57, 3.00, 3.03, and 2.23,respectively, at liquid/solid ratio(L/S) equal to 3:20. The adsorption selectivity for impurity ions exhibited the followingorder:Fe >Lu>Tm>Zn>Mg>Ca>Ho>Co>Ni>Cu>Al.
基金Project(2005CB623702) supported by the National Key Basic Research Program of China
文摘A method for the simultaneous separation and determination of organic acids and inorganic anions in Bayer liquors was developed by gradient ion chromatography with suppressed conductivity detection. Formate, acetate, propionate, oxalate, succinate, glutarate, fluoride, chloride and sulfate were separated and determined in 33 min. The samples were pretreated with solid-phase extraction, which has high selectivity for removing a large number of metallic ions in the Bayer liquors, and filtered with a 0.45 μm filter membrane before being injected into the ion chromatographic system. The separation of six organic acids and three inorganic anions was achieved on an IonPac AS11-HC column with KOH as the eluent, and the detection was performed by a conductivity detection mode. No interference is found in the presence of fluorate, chlorate and sulphate when organic acids are determined. The calibration graphs of peak area for all the analytes are linear over a wide range. The relative standard derivation of the peak area of analytes is less than 2.14%. Under optimum conditions the detection ranges from 0.2 to 100.0 mg/L. The average recoveries of the added standards are between 94.3% and 102.8%.
文摘The new catalytic kinetic spectrophotometric method for Au（III） determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate （（NH4）2S2O8） with nitrilo triacetic acid as an activator in microemulsion and H2SO4 medium. Under optimum conditions, there was the linearity of the calibration curve in the concentration range from 0 to 20 μg/L Au（Ⅲ） at 520 nm. The relative standard deviation was 3.0% with a correlation coefficient of 0.9986. The detection limit achieved was 9.75 × 10^-5 μg/mL. A new method using a column packed with sulfhydryl dextrose gel （SDG） as a solid-phase extractant has been developed for the preconcentration and separation of Au（Ⅲ） ions. The method has been applied to the determination of trace gold with satisfactory results.
文摘A new analytical procedure based on solid-phase extraction method coupled to GC-FID has been developed and validated for the determination of five phthalate esters （PAEs） （dimethyl-（DMP）, diethyl-（DEP）, di-n-butyl-（DBP）, di-2-ethylhexyl- （DEHP）, di-n-octyl-（DOP）） in fish samples. There was a good linear relationship in the range of 0.05-10μg with the detection limits of 0.09-0.16ng .The recoveries obtained for PAEs ranged from 88.6% to 96.4%with RSD of 4.2%-10.2%.The applicability of the developed method was demonstrated for real fish samples.
文摘A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 and Oasis HLB. Parameters that influence the extraction efficiency such as the eluent volume, the sample loading volume, the addition of organic solvent to water sample, sorbent drying and elute concentration were optimized. The innovation of this work was the examination of the use of a centrifugation technique in both the drying and elution steps. When combined with centrifugation, the volume of the elution solvent was reduced to 2 mL and the time for sorbent drying decreased also to 10 min under vacuum. Under the optimized conditions, this method showed good recoveries higher than 65% - 68% for the 67 analyzed pesticides using the C18 and HLB cartridges with relative standard deviations lower than 9.7% - 12.3%. Limits of quantification were between 2 and 20 ng.L–1. The simplicity of the described method, use of less of organic solvent, short procedure time, and good recoveries demonstrate the advantages of this environmentally friendly approach for routine analysis of numerous samples.
基金This work was supported by grants from the National Natural Science Foundation of China Key Program(NO.81530094)General Program(NO.81573574,81873193)the Science and Technology Development Project of Jilin Province(20190201283JC).
文摘Enrichment of trace bioactive constituents and metabolites from complex biological samples is challenging.This study presented a one-pot synthesis of magnetic polydopamine nanoparticles(Fe3O4@-SiO2@PDA NPs)with multiple recognition sites for the magnetic dispersive solid-phase extraction(MDSPE)of ginsenosides from rat plasma treated with white ginseng.The extracted ginsenosides were characterized by combining an ultra-high-performance liquid chromatography coupled to a highresolution mass spectrometry with supplemental UNIFI libraries.Response surface methodology was statistically used to optimize the extraction procedure of the ginsenosides.The reusability of Fe3O4@-SiO2@PDA NPs was also examined and the results showed that the recovery rate exceeded 80%after recycling 6 times.Furthermore,the proposed method showed greater enrichment efficiency and could rapidly determine and characterize 23 ginsenoside prototypes and metabolites from plasma.In comparison,conventional methanol method can only detect 8 ginsenosides from the same plasma samples.The proposed approach can provide methodological reference for the trace determination and characterization of different bioactive ingredients and metabolites of traditional Chinese medicines and food.
文摘Liquid-liquid extraction-thin layer chromatography （LLE-TLC） has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction （SPE） is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography （HPTLC） has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, ＇were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories.
基金supported by the Natural Sciences and Engineering Research Council of Canada,NSERC(Grant No.:IRCPJ 184412-15).
文摘Improved analytical methods for the metabolomic profiling of tissue samples are constantly needed.Currently,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the endogenous metabolome.In this study,solid-phase microextraction(SPME)fibers were used to monitor changes in endogenous compounds in homogenized and intact ovine lung tissue.Following SPME,a Biocrates AbsoluteIDQ assay was applied to make a downstream targeted metabolomics analysis and confirm the advantages of in vivo SPME metabolomics.The AbsoluteIDQ kit enabled the targeted analysis of over 100 metabolites via solid-liquid extraction and SPME.Statistical analysis revealed significant differences between conventional liquid extractions from homogenized tissue and SPME results for both homogenized and intact tissue samples.In addition,principal component analysis revealed separated clustering among all the three sample groups,indicating changes in the metabolome due to tissue homogenization and the chosen sample preparation method.Furthermore,clear differences in free metabolites were observed when extractions were performed on the intact and homogenized tissue using identical SPME procedures.Specifically,a direct comparison showed that 47 statistically distinct metabolites were detected between the homogenized and intact lung tissue samples(P<0.05)using mixed-mode SPME fibers.These changes were probably due to the disruptive homogenization of the tissue.This study's findings highlight both the importance of sample preparation in tissue-based metabolomics studies and SPME's unique ability to perform minimally invasive extractions without tissue biopsy or homogenization while providing broad metabolite coverage.
基金financially supported by the National Natural Science Foundation of China (No.20471051.)
文摘The solid-phase extraction（SPE） technique applied to the extraction of organic compound was creatively used as the extraction of inorganic gold in the paper.Two types of techniques were proposed and explored,namely the SPE and the liquid–liquid extraction（LLE） of the quaternary ammonium surfactant [cetytrimethyl ammonium bromide（CTMAB）,cetyl pyridine bromide（CPB）,benzyl dimethyl dodecyl ammonium chloride（BDMDAC）,and dodecyl trimethyl ammonium chloride（DTMAC）].The surfactant could react with Au（CN）2^- to form the ionic complex,and the compound could be extracted by SPE column of reversed-phase bonded silica gel.Hence,a new method of SPE was proposed to extract gold with these features of the high selectivity,the reliability,and the simplicity.The experimental result shows that the recovery rate of gold is more than 98 %,and the solid-phase extraction column is not easily damaged and it can be repeatedly used.The new method can be used as the extraction process of gold from alkaline cyanide solution as well.Besides,the paper also puts forward a new process of gold extraction.
基金Financial support from the National Natural Science Foundation of China (Nos. 31471643, 31571925)the Innovation Research Program of the Department of Education of Hebei for Hebei Provincial Universities (No. LJRC009)
文摘In this work, a metal-organic framework derived nanoporous carbon （MOF-5-C） was fabricated and modified with Fe3O4 magnetic nanoparticles. The resulting magnetic MOF-5-derived porous carbon （Fe304@MOF-5-C） was then used for the magnetic solid-phase extraction of chlorophenols （CPs） from mushroom samples prior to high performance liquid chromatography-ultraviolet detection. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and N2 adsorption were used to characterize the adsorbent. After experimental optimization, the amount of the adsorbent was chosen as 8.0 mg, extraction time as 10 min, sample volume as 50 mL, desorption solvent as 0.4 mL （0.2 mL × 2） of alkaline methanol, and sample pH as 6. Under the above optimized conditions, good linearity for the analytes was obtained in the range of 0.8-100.0 ng g 1 with the correlation coefficients between 0.9923 and 0.9963. The limits of detection （SIN= 3） were in the range of 0.25-0.30 ng g-1, and the relative standard deviations were below 6.8%. The result showed that the Fe304@MOF-5-C has an excellent adsorption capacity for the analytes.
基金the National Key Basic Research Science Foundation(Grant No.2006CB202501)
文摘In this paper, a method was established to determine the boiling point distribution of hydrocarbon types in diesel. The diesel sample was separated into the saturate and aromatic fractions by means of solid-phase extraction （SPE）, and each fraction was analyzed by GC/FID-EIMS. According to the relationship between boiling point and retention time of n-paraffins in the chromatogram, the percentages of saturates and aromatics at each temperature interval were calculated. According to the average mass spectra of the saturate and aromatic fractions at each temperature interval, the hydrocarbon types of the sample were identified through summation of characteristic mass fragments. Using this method, the changes in composition of diesel during hydrotreating process were studied. The results showed that hydrogenation of aromatics is the main reaction during the hydrotreating process. The more rings the aromatics have, the easier the hydrogenation reactions would take place. The aromatics were converted into cycloparaffins via the hydrogenation and saturation process, leading to an increase in low boiling point fractions in the hydrotreated oil.
