3,432 results match your criteria Journal of chromatographic science[Journal]


Determination of Ibuprofen and Phenylephrine in Tablets by High-Performance Thin Layer Chromatography and in Plasma by High-Performance Liquid Chromatography with Diode Array Detection.

J Chromatogr Sci 2019 Apr 17. Epub 2019 Apr 17.

Pharmaceutical Analysis Department, Faculty of Pharmacy, Damanhour University, 22511, Damanhour, Egypt.

Two chromatographic methods (high performance thin layer chromatography (HPTLC) and high performance liquid chromatography-diode array detector (HPLC-DAD)), were addressed for the analysis of a mixture consisted of phenylephrine hydrochloride and ibuprofen in two forms bulk and their combined dosage form. This binary mixture is considered to be a challenging one as the two drugs differ greatly in their chemical and physical properties. Not only this affects their simultaneous analysis, but also hinders their simultaneous extraction from biological fluids as plasma. Read More

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http://dx.doi.org/10.1093/chromsci/bmz031DOI Listing

Simultaneous Quantification of Chlorpheniramine, Phenylephrine, Guaifenesin in Presence of Preservatives with Detection of Related Substance Guaiacol in their Cough Syrup by RP-HPLC and TLC-Densitometric Methods.

J Chromatogr Sci 2019 Apr 17. Epub 2019 Apr 17.

Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, Kasr El-Aini Street, Cairo 11562, Egypt.

Two sensitive chromatographic methods have been developed, and validated for chlorpheniramine maleate (CM), phenylephrine (PE) and guaifenesin (GF) determination in their mixture and in presence of GF related substance guaiacol (GL) and preservative namely; sodium benzoate (NaB). The first method was based on thin layer chromatographic separation (TLC) followed by densitometric determination of the separated spots. The separation was achieved using silica gel 60 F254 TLC plates and ethyl acetate: methanol: toluene: ammonia (7:1. Read More

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http://dx.doi.org/10.1093/chromsci/bmz027DOI Listing

A Brief Overview of HPLC-MS Analysis of Alkyl Methylphosphonic Acid Degradation Products of Nerve Agents.

Authors:
Clayton B'Hymer

J Chromatogr Sci 2019 Apr 17. Epub 2019 Apr 17.

U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Division of Applied Research and Technology, 1090 Tusculum Avenue, Cincinnati, OH 45226, USA.

The analysis of degradation products from the classic chemical warfare nerve agents by high-performance liquid chromatography-mass spectrometry has been of much interest in recent years owing to the possible use as a terrorist weapon, and the incidents of chemical weapon usage in recent years in war torn countries. The alkyl methylphosphonic acid degradation products are of a particular interest, and they represent a specific chromatographic technical challenge for use in typical separation systems. Various published methods are summarized in this review and some of the problems associated with the analysis of these compounds are discussed. Read More

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http://dx.doi.org/10.1093/chromsci/bmz034DOI Listing

A New HPLC-DAD Method for the Concurrent Determination of Hydroquinone, Hydrocortisone Acetate and Tretinoin in Different Pharmaceuticals for Melasma Treatment.

J Chromatogr Sci 2019 Apr 3. Epub 2019 Apr 3.

Department of Agro-Environmental Sciences, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan.

A new simple and robust HPLC-DAD method was developed for the concurrent analysis of hydroquinone (HQ), hydrocortisone acetate (HCA) and tretinoin (TRN) triple combination for the first time using an Inertsil ODS 3-C18 column (150 mm × 4.6 mm, 5 μm particle size) column with 0.05 M phosphate buffer (pH 5. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmz020DOI Listing
April 2019
7 Reads

Ligand Exchange Thin Layer Chromatographic Enantioresolution of (RS)-Ketorolac and (RS)-Etodolac and Recovery of Native Enantiomers.

J Chromatogr Sci 2019 Apr 3. Epub 2019 Apr 3.

Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, India.

Direct resolution of (RS)-ketorolac and (RS)-etodolac has been achieved by ligand exchange thin layer chromatography. Cu(II) has been used as a complexing ion with three enantiomerically pure amino acids (namely, l-tryptophan, l-histidine and l-phenylalanine) as chiral dopants. Chromatograms were developed using different combinations of solvent systems in different ratio having no chiral additive. Read More

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http://dx.doi.org/10.1093/chromsci/bmz023DOI Listing
April 2019
1.363 Impact Factor

Monitoring of Clotrimazole Degradation Pathway in Presence of its Co-formulated Drug.

J Chromatogr Sci 2019 Mar 31. Epub 2019 Mar 31.

Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, Al kasr al ainy street - Al Sayeda Zeinab, Egypt.

Two stability-indicating chromatographic methods for the determination of clotrimazole and its two acid induced degradation products, with dexamethasone acetate without prior separation. First method depends on RP-HPLC utilizing ODS-3 Inertsil C18 column. Mobile phase consists of acetonitrile:phosphate buffer (pH 6. Read More

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http://dx.doi.org/10.1093/chromsci/bmz024DOI Listing
March 2019
1 Read

Simultaneous Determination of Eight Active Compounds in Baitouweng Decotion and its Single Herbs.

J Chromatogr Sci 2019 Mar 31. Epub 2019 Mar 31.

Shandong Binzhou Animal Science and Veterinary Medicine Academy, No. 169 Huanghe 2 Road, Economic-Technological Development Area, Binzhou 256600, China.

Baitouweng Decotion (BD) is a famous traditional Chinese medicinal prescription, which is composed of Pulsatilla chinensis (bunge) regel, Coptis chinensis franch., Phellodendron chinense and Cortex Fraxini. In this study, a simple and sensitive high performance liquid chromatography coupled with ultraviolet detection method was established for the simultaneous determination of eight marker compounds including Esculin, Fraxin, Esculetin, Fraxetin, Columbamine, Coptisine, Palmatine Chloride and Berberine hydrochloride in BD, the single herbs and their negative controls. Read More

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http://dx.doi.org/10.1093/chromsci/bmz022DOI Listing
March 2019
1 Read

Sensitive Ultra-performance Liquid Chromatography Tandem Mass Spectrometry Method for Determination of Cycloserine in Plasma for a Pharmacokinetics Study.

J Chromatogr Sci 2019 Mar 30. Epub 2019 Mar 30.

School of Pharmacy, University of the Western Cape, Private Bag X17, Bellville 7535, Cape Town, South Africa.

A simple and sensitive ultra-performance liquid chromatography tandem mass spectrometry method has been developed and validated for the analysis of cycloserine in patients' plasma. Using methanol, cyloserine and propranolol (internal standard (IS)) was extracted from plasma by protein precipitation procedure. The chromatographic separation was successfully achieved on Phenomenex KinetexTM PFP C18 (2. Read More

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http://dx.doi.org/10.1093/chromsci/bmz028DOI Listing
March 2019
3 Reads

Determination of Tartrazine, Lutein, Capsanthin, Canthaxanthin and β-Carotene in Animal-Derived Foods and Feeds by HPLC Method.

J Chromatogr Sci 2019 Mar 30. Epub 2019 Mar 30.

National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, No.1 Shizishan Street, Wuhan, Hubei, 430070, People's Republic of China.

Pigments are still widely used in food and feed industry and their resides in food might be harmful to human health due to their side effects. A high performance liquid chromatography (HPLC) method for simultaneous determination of pigments including tartrazine, lutein, capsanthin, canthaxanthin and β-carotene in animal-derived foods (including the muscle and liver of swine, the muscle, liver and skin of chicken and duck, and the muscle of fish) and feeds (swine, chicken and duck) was developed. Lutein, capsanthin, canthaxanthin and β-carotene were extracted with acetonitrile-ethyl acetate by ultrasonication, and tartrazine was extracted with water, followed by defatting with n-hexane and clean-up by solid phase extraction on weak anion exchange cartridges. Read More

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http://dx.doi.org/10.1093/chromsci/bmz019DOI Listing
March 2019
2 Reads

Eco-friendly Evaluation of Rifaximin in Tablets by Capillary Electrophoresis.

J Chromatogr Sci 2019 Mar 30. Epub 2019 Mar 30.

Department of Pharmaceutics, São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, São Paulo, Brazil.

Rifaximin, an oral antimicrobial, has no standardized analytical methods in many official compendia. In this context, the aim was to develop and validate an analytical method by capillary electrophoresis for quantification of rifaximin in tablets. The choice of capillary electrophoresis was based on the concepts of green analytical chemistry, taking into account the health of the operator and environment, analytical conscience, as well as the parameters of linearity, selectivity, precision, accuracy and robustness. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmz005DOI Listing
March 2019
2 Reads

Determination of Cholesterol and its Derivatives in Nanoliposomes as Drug Delivery Conveyances by HPLC-UV: A Simple, Accurate and Cost-Effective Method Development and Validation Approach.

J Chromatogr Sci 2019 Mar 30. Epub 2019 Mar 30.

Research Institute of Petroleum Industry (RIPI), PO Box 1485733111, Tehran, Iran.

Nanoliposomes are extensively used as ideal vehicles in drug delivery systems due to their unique biocompatibility and biodegradability properties. They can be used as sustained release and target selective conveyances to deliver the encapsulated drugs at specific cells or tissues by improving their efficacy along with reducing the side effects. As an analytical perspective, the determination of various lipid components in the final formulation is one of the practical issues while the agents are applied in an industrial-scale. Read More

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http://dx.doi.org/10.1093/chromsci/bmz021DOI Listing
March 2019
1 Read

Surface Design of Enantiomeric HPLC Separation on Vancomycin and Teicoplanin-Based Stationary Phases, a Tool for Chiral Recognition of Model β-Blockers.

J Chromatogr Sci 2019 Mar 20. Epub 2019 Mar 20.

Department of Pharmaceutical Chemistry, German University in Cairo, 11835, Cairo, Egypt.

A quality-by-design approach was adopted for enantioseparation of atenolol on Vancomycin and Teicoplanin-based chiral stationary phases using reversed phase (RP) mode and polar ionic mode (PIM), respectively to account for major forces involved in enantiorecognition of β-blockers on macrocyclics. A fractional factorial screening design for the two modes; followed by a central composite optimization design and regression analysis were able to point out critical factors and chromatographic responses and robust surface of the design. Within the studied range of flow the optimal was 0. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmz018DOI Listing
March 2019
2 Reads

Optimized Gas Chromatography-Tandem Mass Spectrometry for 1,1'-sulfonylbis[2-(methylthio) ethane] Quantification in Human Urine.

J Chromatogr Sci 2019 Mar 18. Epub 2019 Mar 18.

Department of Medical CBRN Defense, University of Health Sciences, Ankara 06018, Turkey.

Sulfur mustard (SM) which is a bifunctional alkylating vesicant is one of the mostly used chemical warfare agent in First World War and the Iran-Iraq War. β-Lyase metabolites of SM especially 1,1'-sulfonylbis[2-(methylthio)ethane] (SBMTE) is an unequivocal biomarker of the exposure. An optimized gas chromatography-tandem mass spectrometry method was developed and validated for the retrospective detection of SBMTE in human urine. Read More

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http://dx.doi.org/10.1093/chromsci/bmz017DOI Listing
March 2019
1 Read

Comparative Analysis of Ginsenosides and Oligosaccharides in White Ginseng (WG), red Ginseng (RG) and Black Ginseng (BG).

J Chromatogr Sci 2019 Mar 6. Epub 2019 Mar 6.

China Academy of Chinese Medical Sciences, No. 16, Nanxiao Road, Dongzhimen, Dongcheng District, Beijing 100700, China.

Ginsenosides and oligosaccharides were comparatively analyzed in WG, RG and BG. The HPLC fingerprints of ginsenosides and oligosaccharides were established to unravel the characteristics of ginsenosides and oligosaccharides. The primary ginsenosides (Rg1, Rb1, Re, Rc, Rb2 and Rd, etc. Read More

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http://dx.doi.org/10.1093/chromsci/bmz004DOI Listing
March 2019
1 Read

Simultaneous Determination and Quantitation of Diosmetin and Hesperetin in Human Plasma by Liquid Chromatographic Mass Spectrometry With an Application to Pharmacokinetic Studies.

J Chromatogr Sci 2019 Feb 27. Epub 2019 Feb 27.

Bioequivalence Study Centre, Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India.

Among the secondary metabolites which are widely distributed in plants and foods in plant origin flavonoids is important one. Flavonoids have antioxidant activities as free radical scavenging action. They also have anti-inflammatory, antiulcer and anti-carcinogenic activities. Read More

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http://dx.doi.org/10.1093/chromsci/bmz015DOI Listing
February 2019
6 Reads

Chirobiotic V Versus Chiralpak ID for the Enantioselective Chromatographic Separation of Chloroquine: Stability and Validation Study.

J Chromatogr Sci 2019 Feb 23. Epub 2019 Feb 23.

Departamento de Produtos Farmacêuticos, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.

Chloroquine is a chiral antimalarial drug and demonstrates enantioselective pharmacodynamic and pharmacokinetic properties. However, this drug is administered as racemate. The knowledge of stereoselective aspects of these agents may be useful to better understand their mechanisms of action and to optimize their safety and/or clinical efficacy. Read More

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http://dx.doi.org/10.1093/chromsci/bmz014DOI Listing
February 2019
1 Read

Development of a Rapid Method for the Determination of Phenolic Antioxidants in Dark Chocolate Using Ultra Performance Liquid Chromatography Coupled to Orbitrap Mass Spectrometry.

J Chromatogr Sci 2019 Feb 23. Epub 2019 Feb 23.

Laboratory of Food and Environmental Investigations, Institute of Food Safety, Animal Health and Environment "BIOR", Lejupes iela 3, Riga, Latvia.

Development of a new comprehensive method based on one-step liquid-liquid extraction (LLE) combined with ultra-high-performance liquid chromatography-Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap-HRMS) for the determination of eight phenolic compounds in dark chocolate is demonstrated. The study focuses on the optimization of sample preparation, chromatographic separation and Orbitrap-HRMS detection parameters to adjust selectivity and sensitivity of the method. The LLE mixture of formic acid-water-acetonitrile (2:58:40, v/v) and hexane at the component ratio of 1:1 (v/v) was applied for sample preparation. Read More

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http://dx.doi.org/10.1093/chromsci/bmz013DOI Listing
February 2019
1 Read

Determination and Quantitative Comparison of Nucleosides in two Cordyceps by HPLC-ESI-MS-MS.

J Chromatogr Sci 2019 Feb 23. Epub 2019 Feb 23.

Department of Pharmaceutical Analysis Research, College of Pharmacy, Hebei Medical University, Shijiazhuang, PR China.

A hybrid quadruple linear ion trap liquid chromatography-tandem mass spectrometry (LC-MS-MS) analytical method has been developed for simultaneous determination of 13 nucleosides from Cordyceps cicadae and Cordyceps sinensis for assessing whether C. cicadae can become a substitute for C. sinensis, based on that C. Read More

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http://dx.doi.org/10.1093/chromsci/bmz012DOI Listing
February 2019
3 Reads
1.363 Impact Factor

Comparative Metabolite Profiling of Four Citrus Peel Cultivars via Ultra-Performance Liquid Chromatography Coupled with Quadrupole-Time-of-Flight-Mass Spectrometry and Multivariate Data Analyses.

J Chromatogr Sci 2019 Apr;57(4):349-360

Department of Pharmacognosy, Faculty of pharmacy, Cairo University, Cairo, Egypt.

Citrus plants are one of the most economical fruit bearing trees grown worldwide for their medicinal use as well as for the flavor and food industry. This study attempts to characterize the metabolome difference in polyphenols of four Citrus species fruit peels; C. reticulata Blanco cv. Read More

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http://dx.doi.org/10.1093/chromsci/bmz006DOI Listing
April 2019
2 Reads

Global Plasma Profiling for Colorectal Cancer-Associated Volatile Organic Compounds: a Proof-of-Principle Study.

J Chromatogr Sci 2019 Feb 23. Epub 2019 Feb 23.

Department of Oncology, Wayne State University School of Medicine, Detroit MI, USA.

Volatile organic compounds (VOCs) could reflect changes resulting from ongoing pathophysiological processes and altered body metabolisms, and thus have been studied for various types of cancers. We aimed to test an advanced global metabolomic technique to characterize circulating VOCs in patients diagnosed with colorectal cancer (CRC). We employed solid-phase microextraction (SPME) and comprehensive two-dimensional gas chromatography mass-spectrometry (GC × GC-MS). Read More

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http://dx.doi.org/10.1093/chromsci/bmz011DOI Listing
February 2019
1 Read

Purification of Flavonolignan Diastereoisomers from Arenaria kansuensis by Two-Dimensional Liquid Chromatography Combined with Solid-Phase Extraction.

J Chromatogr Sci 2019 Feb 7. Epub 2019 Feb 7.

Northwest Institute of Plateau Biology, College of Life Science, Chinese Academy of Sciences, Xining, Qinghai, P.R. China.

Herbal plants are significant for the reason that they have a great potential in discovering drug precursors. However, how to purify compounds with higher purity from them is a question which needs to be discussed. In present study, an offline 2D reversed-phase (RP) preparative liquid chromatography coupled with solid-phase extraction (SPE) method was successfully developed for the separation of flavonolignan diastereoisomers from Arenaria kansuensis. Read More

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http://dx.doi.org/10.1093/chromsci/bmz010DOI Listing
February 2019
2 Reads
1.363 Impact Factor

Development and Validation of High-Performance Thin-layer Chromatographic Method for Quantification of Berberine in Rhizomes of Coptis teeta Wall, an Endangered Species Collected from Arunachal Pradesh, India.

J Chromatogr Sci 2019 Feb 7. Epub 2019 Feb 7.

Department of Pharmaceutical Sciences, Dibrugarh University, Dibrugarh, Assam, India.

The high polarity of the protoberberine alkaloids present in Coptis teeta has made it difficult to quantify the alkaloids. This study was designed to develop and validate a thin-layer chromatography (TLC) densitometric-based method using high-performance thin-layer chromatography for quantification of berberine. The separation was achieved in a solvent system consisting of butanol:ethyl acetate:formic acid:water by volume on TLC aluminum plate precoated with silica gel 60 F254. Read More

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http://dx.doi.org/10.1093/chromsci/bmz009DOI Listing
February 2019
6 Reads

Simultaneous Determination of Anti-diabetic Drugs in Their Combined Dosage Forms Using HPLC: An Experimental Design Approach.

J Chromatogr Sci 2019 Apr;57(4):339-348

Department of Pharmaceutical Analysis & Quality Assurance, GITAM Institute of Pharmacy, GITAM (Deemed to be University), Visakhapatnam, India.

A liquid chromatographic method has been established for the separation of five presently existing anti-diabetic drugs-metformin, pioglitazone, glibenclamide, glimepiride and repaglinide using design of experiments methodology. The main objective of this method is to identify the suitable conditions for the adequate separation of these five drugs with minimal analysis time. Experiment design is one of the Quality by design approaches, which incorporates multifaceted combinations of independent variables and their interactions during the optimization of analytical methods for the determination of drugs. Read More

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http://dx.doi.org/10.1093/chromsci/bmz003DOI Listing
April 2019
1 Read

Enantioseparation of Synthetic Cathinones Enantiomers with Tertiary Amine Structure in Urine and Plasma.

J Chromatogr Sci 2019 Apr;57(4):361-368

Chemistry Department, College of science, United Arab Emirates University, Al-Ain, UAE.

A sensitive and selective method for detection and quantitation of the enantiomers of 18 synthetic cathinones with tertiary amine structure using HPLC-UV-VIS has been developed. Two chiral columns, Astec Cellulose DMP and Amylose-based Chiralpak AS-H, have been examined separately. Mobile phase composed of hexane, isopropanol and triethylamine (99. Read More

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http://dx.doi.org/10.1093/chromsci/bmz008DOI Listing
April 2019
2 Reads

Synthesis of High Purified Tulobuterol and Its Study of the Organic Impurities.

J Chromatogr Sci 2019 Apr;57(4):299-304

Beijing Key Laboratory of Drug Delivery and Novel Formulation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.

The synthetic condition of tulobuterol was optimized to gain lower impurity content. Two intermediates were analyzed, and three degradation impurities were isolated using preparative liquid chromatography for the first time and subsequently characterized by various techniques. Possible degradation impurities were deduced by an oxidative mechanism. Read More

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http://dx.doi.org/10.1093/chromsci/bmy083DOI Listing
April 2019
2 Reads

Rapid Determination of Adenosine in Cordyceps by Online Extraction HPLC.

J Chromatogr Sci 2019 Apr;57(4):381-384

Key Laboratory of State Administration of Traditional Chinese Medicine, Sunshine Lake Pharma Co., LTD, Dongguan, Guangdong, China.

In this study, determination of adenosine in Cordyceps was accomplished by an online pressurized liquid extraction HPLC, and a poroshell column was employed for rapid HPLC separation. The Cordyceps sample powder was filled into a hollow guard column and extracted by thermal and pressurized water (75°C, 150 bar) for 3 min. Chromatographic separation was conducted on a poroshell 120 SB-Aq (4. Read More

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http://dx.doi.org/10.1093/chromsci/bmz007DOI Listing
April 2019
1 Read

Development and Validation of Simple LC-MS-MS Assay for the Quantitative Determination of Ticagrelor in Human Plasma: its Application to a Bioequivalence Study.

J Chromatogr Sci 2019 Apr;57(4):331-338

Department of Pharmaceutical Biochemistry, College of Pharmacy, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, Republic of Korea.

A sensitive, rapid, reproducible and reliable high-performance liquid chromatography-electrospray ionization tandem mass spectrometric method has been developed and fully validated for the determination of ticagrelor in human plasma using ticagrelor-d7 as an internal standard (IS) after one-step liquid-liquid extraction with ethyl acetate. Ticagrelor and IS were detected in the multiple reaction monitoring mode at m/z transition 523.4 > 127. Read More

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http://dx.doi.org/10.1093/chromsci/bmz001DOI Listing
April 2019
4 Reads

Estimation of C2H5-Benzenes in Refinery Streams.

J Chromatogr Sci 2019 Apr;57(4):291-298

Indian Oil Corporation Limited, Research and Development Centre, Sector 13, Faridabad, Haryana, India.

A simple and direct gas chromatography-mass spectrometry method for routine estimation of C2 H5-alkylbenzenes (or C2-alkylbenzenes), namely, ethylbenzene and m/p- and o-xylenes in the boiling range of 80°C-400°C, including diesel range streams using deuterated ethylbenzene as internal standard has been described. Estimation of C2-alkylbenzenes in feeds and products is important for monitoring the reaction kinetics in certain secondary processes which involve conversion of low value, aromatic-rich diesel range boiling streams to produce aromatic-based petrochemical feedstocks upto xylenes. The method developed takes advantage of chromatographic separation and resolution masses of fragment ions of the compounds of interest for estimation. Read More

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http://dx.doi.org/10.1093/chromsci/bmz002DOI Listing
April 2019
1 Read

A Validated Ultra-Performance Liquid Chromatography Tandem Triple Quadrupole Mass Spectrometric Method for Fast Determination of Losartan in Rabbit Plasma.

J Chromatogr Sci 2019 Apr;57(4):323-330

Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh-11451, Saudi Arabia.

A rapid UPLC-MS-MS method was developed and validated for determination of losartan in rabbit plasma. Protonated adducts of losartan and eprosartan (IS) were monitored in multiple reaction monitoring mode. Molecular masses of daughter species of losartan were m/z 423. Read More

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http://dx.doi.org/10.1093/chromsci/bmy114DOI Listing
April 2019
12 Reads

Comparative Study of Quinolines and Tetrahydroquinolines Sorption on Various Sorbents from Water-Acetonitrile Solutions.

J Chromatogr Sci 2019 Apr;57(4):369-380

Department of Physical Chemistry and Chromatography, Samara National Research University Named after Academician S.P. Korolev, 34 Moskovskoye Shosse, Samara, Russia.

The retention of 16 quinoline and tetrahydroquinoline derivatives was investigated under liquid chromatography conditions using porous graphitized carbon (PGC), octadecyl silica (ODS) and hypercrosslinked polystyrene (HCLP) stationary phases. For most of the analytes, retention on PGC was greater than on ODS, while retention on HCLP was even greater than on both ODS and PGC. The non-linearity of retention dependencies on acetonitrile content in the eluent was observed for compounds containing carboxy, hydrazo and methoxy groups. Read More

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http://dx.doi.org/10.1093/chromsci/bmy111DOI Listing
April 2019
2 Reads

Validated Chromatographic Methods for Simultaneous Determination of Calcipotriol Monohydrate and Betamethasone Dipropionate in the Presence of Two Dosage Form Additives.

J Chromatogr Sci 2019 Apr;57(4):305-311

Analytical Chemistry Department, Faculty of Pharmacy, Cairo University, Kasr El Aini Post, Cairo, Egypt.

Two chromatographic methods were developed, optimized and validated for simultaneous determination of calcipotriol monohydrate (CPM) and betamethasone dipropionate (BMD) in the presence of two dosage form additives named; butylated hydroxytoluene (BHT) and alpha-tocopherol (TOCO). The proposed methods were accurate, sensitive and specific. The first method based on using aluminum thin-layer chromatographic plates precoated with silica gel GF254 as a stationary phase and chloroform-ethyl acetate-toluene (5:5:3, by volume) as a developing system. Read More

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http://dx.doi.org/10.1093/chromsci/bmy112DOI Listing
April 2019
2 Reads

With or Without Internal Standard in HPLC Bioanalysis. A Case Study.

J Chromatogr Sci 2019 Mar;57(3):243-248

Departament of Pharmaceutical Sciences, Faculty of Pharmacy, University of Medicine and Pharmacy from Tîrgu Mures, Gheorghe Marinescu street 38, Tîrgu Mures, Romania.

The mandatory strategy of using internal standard in HPLC is still controversial. Despite that the introduction of internal standard methodology in the early stage of development of HPLC technology was used to improve method accuracy and precision, there are still practical situations in which a simple external standard quantification is adequate. The aim of the study is to compare the determination of meloxicam (MXC) in human plasma by HPLC with or without using an internal standard according to some key points related to the reason of introducing the internal standardization such as the reducing of sample preparation errors or variability for low injection volumes. Read More

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http://dx.doi.org/10.1093/chromsci/bmy106DOI Listing
March 2019
2 Reads

High-Performance Thin-Layer Chromatography Method for Simultaneous Determination of Antipsychotic and Medicinally Important Five β-Carboline Alkaloids.

J Chromatogr Sci 2019 Apr;57(4):312-322

Department of Botany, Savitribai Phule Pune University, Pune, MH, India.

This is the first report on the development and validation of high-performance thin-layer chromatography (HPTLC) method for simultaneous analysis of five antipsychotic and medicinally important β-carboline alkaloids (βCAs), namely, harmalol, harmaline, harmine, harmane and norharmane. These βCAs occurs in both plant and animal system including human being. In the present investigation, their best separation was achieved using an optimized mobile phase, chloroform: methanol: glacial acetic acid (7. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmy113DOI Listing
April 2019
4 Reads

Fingerprint Analysis and Multi-Component Determination of Ribonucleic Acid for Injection II Recipe by HPLC-DAD and LC-ESI-MS Methods.

J Chromatogr Sci 2019 Mar;57(3):238-242

Center of Research & Development, Changchun University of Chinese Medicine, No 1035, Boshuo Road Changchun, Jilin, China.

Using high-performance liquid chromatography (HPLC), a quantitative method was developed to control the quality of ribonucleic acid for injection II (RA-II), which is used as an anti-cancer drug clinically in China. Using nuclease enzyme and under optimal hydrolysis conditions, the unstable RNA was hydrolyzed into stable nucleosides and nucleotides, which were easily detected by HPLC with diode array detection. Furthermore, by analyzing HPLC chromatograms of 10 batches of samples, six common peaks, namely, cytosine nucleotide, uracil nucleotide, adenine nucleotide, guanine nucleotide, guanosine and adenine, were identified by a HLPC coupled with electrospray ionization mass spectrometry. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmy105DOI Listing
March 2019
12 Reads

Preparative separation of quercetin, ombuin and kaempferide from Gynostemma pentaphyllum by high-speed countercurrent chromatography.

J Chromatogr Sci 2019 Mar;57(3):265-271

College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Qingdao, P. R. China.

An efficient method for the preparative separation of quercetin, ombuin and kaempferide from Gynostemma pentaphyllum by high-speed countercurrent chromatography (HSCCC) was successfully developed for the first time. The extraction conditions were optimized by an orthogonal array design L9 (34), while quercetin, ombuin and kaempferide were efficiently released from rutin, ombuoside and kaempferide glucoside by hydrochloric acid hydrolysis, respectively. Quercetin was purified by HSCCC with two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (4:5:4:5, v/v) in a single run. Read More

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http://dx.doi.org/10.1093/chromsci/bmy110DOI Listing
March 2019
2 Reads

Optimized liquid chromatography-tandem mass spectrometry for Otaplimastat quantification in rat plasma and brain tissue.

J Chromatogr Sci 2019 Mar;57(3):258-264

Department of Life and Nanopharmaceutical Sciences, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul, South Korea.

An optimized liquid chromatography-tandem mass spectrometry method for simple and sensitive quantification of Otaplimastat in rat plasma and brain tissue was developed and validated. Protein precipitation with acetonitrile was selected for sample preparation method based on recovery and matrix effect. The chromatographic separation of the sample was performed on a reverse-phase AQ column with an isocratic mobile phase consisting of 10 mM ammonium acetate (pH 4. Read More

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http://dx.doi.org/10.1093/chromsci/bmy109DOI Listing
March 2019
4 Reads

Development and Validation of Stability Indicating UPLC-PDA/MS for the Determination of Imiquimod and its Eight Related Substances: Application to Topical Cream.

J Chromatogr Sci 2019 Mar;57(3):249-257

Dr. Reddy's Laboratories Limited, Bachupally, Survey No. 42, 45 & 46, Qutubullapur Mandal Hyderabad, India.

A stability indicating analytical method for imiquimod and its related impurities was developed by ultra-pressure liquid chromatography (UPLC) using design of experiments. This method could quantify imiquimod and all its eight known related impurities in a single run. The optimum separation was achieved on reverse phase Acquity UPLC column (2. Read More

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http://dx.doi.org/10.1093/chromsci/bmy108DOI Listing
March 2019
6 Reads

Response Surface Methodology of Pre-Concentration of Chorophenols from Seawater Samples by Molecularly Imprinted Stir Bar Sorptive Extraction Combined with HPLC: Box-Behnken Design.

J Chromatogr Sci 2019 Mar;57(3):279-289

Department of Marine Chemistry, Faculty of Marine Science, Chabahar Maritime University, Chabahar, Iran.

A novel molecularly imprinted polymer coated stir bar was prepared using 2-chlorophenol (2-CP) as template molecule and used for selective extraction of phenolic compounds including chlorophenols (CPs) directly from seawater samples. Various parameters affecting extraction have been evaluated using one variable-at-a-time and Box-Behnken design. A three-level Box-Behnken experimental design by six factors, which combined the response surface methodology, was used to optimize the selective extraction of the CPs. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmy107DOI Listing
March 2019
5 Reads

Modeling Retention Behavior on Analysis of Hallucinogenic Mushrooms Using Hydrophilic Interaction Liquid Chromatography.

J Chromatogr Sci 2019 Mar;57(3):230-237

Department of Drug and Arson Investigation, Hungarian Institute for Forensic Sciences, Mosonyi Street 9, Budapest, Hungary.

The goal of this work was to investigate and compare the selectivity of three different hydrophilic interaction liquid chromatography (HILIC) charge modulated amide columns, iHILIC®-Fusion, iHILIC®-Fusion(+) and iHILIC®-Fusion(P), for analysis of compounds in hallucinogen mushrooms. An extract of a truffle-like fungus containing psilocin, psilocybin and baeocystin was chosen as test material. Three different modeling methods were applied to describe the retention times of constituents in isocratic separation mode as a function of mobile phase composition, pH and temperature. Read More

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http://dx.doi.org/10.1093/chromsci/bmy104DOI Listing
March 2019
2 Reads

A High Throughput Three-step Ultra-performance Liquid Chromatography Tandem Mass Spectrometry Method to Study Metabolites of Atractylenolide-III.

J Chromatogr Sci 2019 Feb;57(2):163-176

Department of Natural Medicine Chemistry, Institute of Pharmacy, Jiangxi University of Traditional Chinese Medicine, No. 1688 Meiling Avenue, Nanchang, PR China.

Atractylodes macrocephala Koidz (AMK) is a traditional Chinese medicine widely used in the treatment of various diseases, especially spleen deficiency. As the principle active constituents of AMK, however, the metabolites of Atractylenolide-III (A-lactone-III) have not been identified in rats yet. In this study, a three-step high throughput method based on UHPLC-Q-TOF-MS-MS was developed to profile and characterize the metabolites of A-lactone-III in rat feces, urine and plasma. Read More

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http://dx.doi.org/10.1093/chromsci/bmy098DOI Listing
February 2019
4 Reads

Simultaneous Quantification of Benznidazole and Posaconazole by HPLC-DAD Using QbD Approach.

J Chromatogr Sci 2019 Feb;57(2):156-162

Department of Pharmaceutical Sciences, Federal University of Pernambuco, PE, Brazil.

Objective: To develop an analytical method to simultaneous quantification of benznidazole (BNZ) and posaconazole (POS) by high-performance liquid chromatography with diode-array detection (HPLC-DAD) using design of experiments.

Methods: Percentages of organic phase, buffer pH and flow rates of mobile phase were selected as independent variables by full factorial design (33), totaling 27 experiments. Significant factors were evaluated using factorial analysis of variance with 95% confidence level. Read More

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http://dx.doi.org/10.1093/chromsci/bmy097DOI Listing
February 2019
3 Reads

Development and Validation of LC-MS-MS Assay for the Determination of the Emerging Alkylating Agent Laromustine and Its Active Metabolite in Human Plasma.

J Chromatogr Sci 2019 Mar;57(3):195-203

Metastagen, Inc., Wilmington, DE, USA.

The objective of this study was to validate a method for the determination of laromustine (VNP40101M) and short-lived its active metabolite (VNP4090CE) that has a half-life in human blood of <90 s in human plasma by liquid chromatography (LC) with tandem mass spectrometric (MS/MS) detection. We overcome the stability dilemma by acidified the human plasma with citric acid. Laromustine "breaks" down on the source of mass spectrometry to give m/z 249 which is the same m/z for VNP4090CE. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmy100DOI Listing
March 2019
7 Reads

HPTLC method for Simultaneous Determination of Norfloxacin and Tinidazole in presence of Tinidazole Impurity.

J Chromatogr Sci 2019 Jan;57(1):81-86

Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Beni-Suef University, Alshaheed Shehata Ahmad Hegazy St., Beni-Suef, Egypt.

Sensitive, selective and accurate high-performance thin layer chromatographic HPTLC method for quantitative determination of Norfloxacin (NF), Tinidazole (TZ) and 2-Methyl-5-nitroimidazole (MNZ) as potential impurity of Tinidazole is developed and validated in the presented work. Calibration curves were linear over the concentration ranges of 0.4-2. Read More

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http://dx.doi.org/10.1093/chromsci/bmy085DOI Listing
January 2019
4 Reads

Separation and Characterization of Unknown Impurities and Isomers in Cefminox Sodium and Study of the Forming Mechanisms of Impurities by Liquid Chromatography Coupled with Ion Trap/Time-Of-Flight Mass Spectrometry.

J Chromatogr Sci 2019 Mar;57(3):204-212

Zhejiang University of Technology, College of Pharmacy, Hangzhou, China.

Thirteen unknown impurities and isomers in cefminox sodium were separated and characterized by liquid chromatography coupled with high-resolution ion trap/time-of-flight mass spectrometry (LC-IT-TOF-MS) with the positive mode of electrospray ionization (ESI) method. New HPLC-gradient elution method was developed for the detection of impurities in cefminox sodium. And the ESI ion trap multiple-stage tandem mass spectrometry had been applied successfully to the direct investigation of impurities and isomers in cefminox sodium. Read More

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http://dx.doi.org/10.1093/chromsci/bmy101DOI Listing
March 2019
7 Reads

Stability-Indicating RP-UPLC Method for Simultaneous Determination of Azilsartan Medoxomil and Chlorthalidone in Tablets in the Presence of Its Degradation Products.

J Chromatogr Sci 2019 Mar;57(3):213-219

Research and Development Department, Eva Pharma for Pharmaceutical and Medical Appliances, Giza, Egypt.

Azilsartan Medoxomil (AZL) angiotensin II receptor blocker and chlorthalidone (CLT) were determined by ultraperformance liquid chromatography (UPLC) method in their combined dosage form, they were both subjected to forced degradation studies under extensive stress conditions. The method is a stability indicating by resolving the investigated drugs from their degradation products. Moreover, the degradation products for both drugs obtained from forced degradation were subjected to LC-MS for structure elucidation. Read More

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http://dx.doi.org/10.1093/chromsci/bmy102DOI Listing
March 2019
25 Reads

Application of Dopant-Assisted Atmospheric Pressure Photoionisation HPLC-MS Method for the Sensitive Determination of Polycyclic Aromatic Hydrocarbons in Dark Chocolate.

J Chromatogr Sci 2019 Mar;57(3):220-229

Institute of Food Safety, Animal Health and Environment "BIOR", Lejupes Street 3, Riga, Latvia.

Multiple food research studies have shown that the polycyclic aromatic hydrocarbon (PAHs) are frequently found in processed cocoa products and chocolate. In a present study a method based on dopant-assisted atmospheric pressure photoionisation (DA-APPI) combined with a liquid chromatography/high-resolution mass spectrometer (HPLC-HRMS) for high-sensitivity analysis of four EU marker PAHs in dark chocolate samples was developed and fully validated according to the performance criteria set in EU guidelines. PAHs detection was achieved by HRMS in positive electrospray ionization mode with toluene used as a dopant to enhance the ionization efficiency of non-polar PAHs. Read More

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http://dx.doi.org/10.1093/chromsci/bmy103DOI Listing
March 2019
4 Reads

A High-Performance Liquid Chromatography Method for Determination of Genotoxic Impurity Hydroxylamine in Drug Substances.

J Chromatogr Sci 2019 Jan;57(1):63-70

Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, Chennai, India.

Hydroxylamine (NH2OH) is widely used in pharmaceutical intermediates and final drug substances synthesis. Since hydroxylamine is a well-known genotoxic impurity compound that needs to be controlled down to ppm level in pharmaceutical compounds. It is very difficult to detect using conventional analytical techniques due to its physical-chemical properties like the lack of chromophore, low molecular weight, the absence of carbon atom and high polarity. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmy082DOI Listing
January 2019
29 Reads

HPTLC-Densitometric Method for Determination of Ascorbic Acid, Paracetamol and Guaifenesin in Presence of Their Toxic Impurities.

J Chromatogr Sci 2019 Feb;57(2):149-155

Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Beni-Suef University, Alshaheed Shehata Ahmad Hegazy St., Beni-Suef, Egypt.

Ascorbic acid (ASC), paracetamol (PAR) and guaifenesin (GUF) are co-formulated together as analgesic and expectorant effervescent powder. This work describes a selective stability indicating HPTLC-densitometric method which is the first developed stability indicating one for chromatographic separation of the three studied drugs in presence of paracetamol toxic impurity [4-aminophenol (4-AP)] and guaifenesin related substance [impurity, (guaiacol) (GUC)]. The chromatographic separation was carried out on HPTLC 60F254 plates using chloroform-acetone-trifluoroacetic acid (6. Read More

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http://dx.doi.org/10.1093/chromsci/bmy096DOI Listing
February 2019
3 Reads

Green Tailoring With Water of Choline Chloride Deep Eutectic Solvents for the Extraction of Polyphenols From Palm Samples.

J Chromatogr Sci 2019 Mar;57(3):272-278

College of Pharmaceutical Science, Hebei University, 180 Wusi East Road, Baoding, China.

To address the problem of high viscosity of deep eutectic solvents (DESs), the viscosities of a series of choline chloride-based DESs and DESs-H2O were determined, and their extraction efficiencies were obtained for the extraction of polyphenols in palm samples. Tailoring the DESs by the addition of water successfully adjusted their viscosity from thousand to single-digit mPa s and aided the extraction of polyphenols from samples, by changing the hydrogen-bonding interactions of DESs. Among the compounds investigated, choline chloride-oxalic acid-water of DESs-H2O with various molar ratios with 1:0. Read More

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https://academic.oup.com/chromsci/advance-article/doi/10.109
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http://dx.doi.org/10.1093/chromsci/bmy099DOI Listing
March 2019
18 Reads

Non-Anthocyanin Phenolic Compounds in Açaí (Euterpe oleracea Mart.) Juice by Ultrahigh-Performance Liquid Chromatography-Diode Array Detector (UHPLC-DAD): A Multivariate Optimization.

J Chromatogr Sci 2019 Feb;57(2):139-148

Department of Food Science. Faculty of Food Engineering, University of Campinas (UNICAMP), Monteiro Lobato Street, Campinas, SP, Brazil.

Currently available high-performance liquid chromatographic (HPLC) methods for the analysis of non-anthocyanin compounds in açaí are time-consuming or employ complex and costly detection systems. Therefore, we hypothesized that by using ultrahigh-performance liquid chromatography interfaced with a diode array detector (UHPLC-DAD) in conjunction with multivariate optimization tools (response surface methodology, Derringer and Suich desirability) would give a simple, fast, effective and reliable method to determine eight phenolic acids and four flavonoids in açaí juice. Three independent variables were assessed: initial acetonitrile (ACN) concentration in the gradient elution, final ACN concentration at the end of the gradient and the linear time of the gradient elution. Read More

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http://fdslive.oup.com/www.oup.com/pdf/production_in_progres
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http://dx.doi.org/10.1093/chromsci/bmy095DOI Listing
February 2019
5 Reads