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Featured Application Note:
Sensitive Stevia Sweetener Analysis by HPLC
Deanna Hurum and Jeffrey Rohrer, Thermo Fisher Scientific
Stevia sweetener analysis is challenging for two reasons: steviol glycoside structural similarities make separation difficult; and the lack of a strong chromphore limits UV detection. This work describes a stable and sensitive HPLC steviol glycosides determination method for commercial sweeteners. |
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High Selectivity Quantitation of Protein Isoforms with MRM3
Kellie Jonakin, Christie Hunter, AB SCIEX
The MRM3 workflow that is possible on the QTRAP® 4500 system is a high selectivity method that provides additional specificity by monitoring the secondary product ions of a peptide of interest, rather than just the product ions. In this work, the CYP450 3A5 protein is specifically quantified in human liver microsomes by monitoring unique peptides to 3A5 protein. |
Transferring Methods to the Agilent 1290 Infinity LC Using Intelligent System Emulation Technology (ISET)
Angelica Gratzfeld-Huesgen, Agilent Technologies
The Intelligent System Emulation Technology (ISET) offers seamless transfer of a method for paracetamol from an LC system with higher delay volume and/or different mixing behavior to the Agilent 1290 Infinity system. |
Transfer of a UPLC Screening Method to Preparative HPLC Purification Using CSH Column Technology and Focused Gradients
Mia Summers and Kenneth J. Fountain, Waters Corporation
This application demonstrates a rapid UPLC screening protocol using high and low pH on a charged-surface hybrid (CSH) column and subsequent scale-up to an efficient preparative HPLC purification using focused gradients. |
Quality control in radiopharmaceutical production by IC
M. Espinosa, J. Chesa-Jiménez, B. Galliker, A. Steinbach, and A. Wille
Quality control of radiopharmaceuticals for positron emission tomography (PET) is challenging, not least because of the tough time limits, the radiation issue, and the near nanomole radiotracer quantities. This article describes how radio IC can control the production of the radionuclide [18F]fluoride (precursor) and the two radiotracers synthesized from it, [18F]fluorodeoxyglucose and [18F]fluorocholine, in accordance with pharmacopoeial regulations. |
Food Additives Analysis
Njies Pedjie, PerkinElmer, Inc.
This application note presents a fast and robust liquid chromatography method to simultaneously test nine widely used additives. Among the additives tested are: preservatives (benzoic acid, sorbic acid, dehydroacetic acid and methylparaben); artificial sweeteners (acesulfame potassium, saccharin and aspartame); flavoring agent (quinine); and a stimulant (caffeine). Method conditions and performance data including precision, accuracy, and linearity are presented. |
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Extraction of Antioxidants from High Density Polyethylene (HDPE) By Pressurized Liquid Extraction (PLE)
Phil Bassignani, FMS, Inc.
Plastics and other polymers are used in a wide spectrum of applications from industrial usage to packaging, including the packaging of food and pharmaceutical products. To enhance functionality, chemical additives are often added to polymers. This application note demonstrates the use of pressurized liquid extraction using the FMS PLE system to extract polymer additives for quatitative analysis by HPLC. Four specific additives of known concentrations were extracted from high density polyethylene (HDPE) and the recoveries measured. |
Extraction of 22 Pain Management Drugs from Urine with LC-MS-MS analysis
Victor Vandell, Biotage AB, Sweden
Using ISOLUTE® SLE+ in 96-Fixed Well Plate Format prior to LC-MS-MS analysis. Screening pain management urine samples for the free drugs is complicated by the metabolism process which converts the free drug to the b-glucuronide form. Patient urine samples can be enzymatically hydrolyzed and extracted to detect the drugs using Supported Liquid Extraction (ISOLUTE SLE+) which offers an efficient alternative to traditional liquid-liquid extraction (LLE) for bioanalytical sample preparation. LOQs for recovered drugs ranged from 10 ng/mL to 0.5 ng/mL with recoveries above 80% and RSDs <10%. |
Determination of 1,4-Dioxane in Drinking Water by Solid Phase Extraction (SPE) and GC-MS with Selected Ion Monitoring (SIM) * EPA Mehod 522
Don Shelly, UCT, Inc
The challenging analysis of highly water soluble 1,4-dioxane has been overcome using UCT ENVIRO-CLEAN® SPE activated carbon cartridge EU52112M6 (Option 1) or EU521146 (Option 2). With EPA Method 522 and GC/MS in selected ion mode (SIM), fortified drinking water has shown recoveries of 92% and RSD values of <3% (n=7) as reported in the J of Chrom. Sci (v 47, Jan 2009). |
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GPC/SEC-Viscometry for molar mass and structure analysis of Carrageenan
Daniela Held, PSS-Polymer Standards Service-USA Inc.
GPC/SEC-Viscometry allows to measure true molar masses for carrageenan samples and helps to detect subtle differences even for samples with very similar molar mass distributions. Structure information is easily accessible with the Mark-Houwink plot. |
Oligomerization and Stability of a Two-Tailed Virus (ATV)
Catarina Rodrigues, Wyatt Technology
ATV is a virus infecting archaea of the hyperthermophilic genus Acidianus, which has the unique property of undergoing a major morphological development outside and independently of the host cell. Virions develop long tails at each pointed end, at temperatures close to that of the host natural habitat, 85 °C. |
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Rapid aroma profiling of cheese using a Micro-Chamber/Thermal Extractor with TD–GC/MS analysis
Gareth Roberts, Markes International Ltd
This Application Note describes the benefits of using Markes’ Micro-Chamber/Thermal Extractor in conjunction with thermal desorption (TD) and GC/MS to analyse the aroma profiles of cheese. Various cheeses are examined and compared, and it is demonstrated how this ‘multi-hyphenated’ technique allows rapid yet powerful assessment of the VOCs released even when they are present at trace-levels and have low odour thresholds. With the ability to detect odour and flavour compounds at far lower, and previously undetectable, levels than techniques currently used in the food industry, the method also uses state-of-the-art software to target and identify specific compounds even at the lowest of levels. |
Fast Simulation of Drug Metabolism Using Electrochemistry-MS
A. Kraj, H-J. Brouwer, M. Eysberg, and J-P. Chervet, Antec
For faster, better, and superior simulation of drug metabolism, Antec has developed a dedicated electrochemistry system, called ROXY™ EC. The system is used up-front MS and allows for the generation and screening of potential metabolites, mimicking P450 enzymatic reactions in a few seconds without any biological interferences. |
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The Preparation and Certification of a 30 ppt Calibration Gas Mixture
Dr. Kevin Cleaver, BOC Limited, A Member of The Linde Group, UK, Linde Gas
This application note describes the challenges in the preparation and certification of a 30 parts per trillion (ppt), also referred to as 30 x 10-12, sulfur hexafluoride gas calibration mixture used as a transfer standard for the determination of anthropogenic carbon dioxide. The feasibility and preparation techniques require very careful evaluation and the analysis is completed by gas chromatography using a gas chromatograph with an electron capture detector (ECD). |
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To advertise or have an application note inserted, contact:
Lee Noyes
+44 1244 629315 | Email
Lindsay Jones
+44 1244 629316 | Email
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