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A detection method based upon aerosol charging was examined for its applicability and performance with high performance liquid chromatography.

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Mass spectrometry (MS) has advanced to analyze ever-larger biomolecules with the invention of soft ionization techniques like electrospray ionization (ESI). Although ESI has provided a method of generating ions of high mass, mass spectrometers generally suffer both lower sensitivity and lower resolution as the mass-to-charge ratio of an ion increases. To extend the mass range of ionized macromolecules beyond the limits of MS, macroion mobility spectrometry utilizes ion mobility sizing to characterize charge-reduced ESI-generated macroions from >5 kDa to beyond megadalton masses. One prominent application of macroion mobility spectrometry, highlighted here, is the high sensitivity analysis of intact proteins, antibodies, and conjugates in which molecular masses range from antibody light-chain fragments to high mass immunoglobulin multimers.

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Out of the several options available for retaining polar compounds like nucleotides, this application note focuses on the use of polar-modified C18 bonded phases for their analysis.

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Electrophoretic techniques, such as sodium dodecyl sulphate polyacrylamide (SDS-PAGE) and isoelectric focusing (IEF) gels, have traditionally been part of release testing in the biopharmaceutical industry. However, these slab gel methods are inconvenient and irreproducible because of the staining/destaining steps used in analyte detection, the use of toxic reagents and high intra- and inter-gel effective mobility variability.

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Out of the several options available for retaining polar compounds like nucleotides, this application note focuses on the use of polar-modified C18 bonded phases for their analysis.

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Fossil fuels are a limited resource, and the petroleum industry is always on the lookout for ways to extract more useful materials from crude oil. This session focuses on the use of mass spectrometry in the analysis of petroleum.

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Semiquantitative elemental analysis by ICP-MS is a powerful tool for quick screening of unknown samples for a wide range of elements.

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Ascentis Express 5 micron columns provide a new choice for improving the performance of traditional HPLC systems. Based on Fused-Core particle technology, Ascentis Express provides the benefits of high speed and high efficiencies without the concerns of smaller particle columns. Due to the high efficiencies at low backpressures, Ascentis Express 5 micron can benefit conventional HPLC users with no drawbacks.

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The potential of the time-of-flight mass spectrometry (TOF-MS) to innovate the analysis of soft drinks is described using gas chromatography (GC) hyphenated to TOF-MS and a new type of ion source, direct analysis in real time (DART), coupled to high-resolution TOF-MS. Head-space solid-phase microextraction (SPME) was used to isolate/extract volatile compounds followed by GC–TOF-MS to identify tainted compound in contaminated soft drinks. Direct analysis in real time–time-of-flight mass spectrometry (DART–TOF-MS) was also used to obtain negative and positive ion profiles of different soft drinks to determine the presence of various compounds, including antimicrobial preservatives, artificial sweeteners, acidulants and saccharides, without any sample preparation and chromatographic separation.

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Nano LC is now widely applied in proteomics, and also is robust enough for application in fields such as pharmaceutical analysis.

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Out of the several options available for retaining polar compounds like nucleotides, this application note focuses on the use of polar-modified C18 bonded phases for their analysis.

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Evaporation-free extraction (no drying down) is highly desirable because of its reduced cost and pollution, higher speed, and less possibility for contamination and conversion. Presented in this article are four types of evaporation-free extraction that are widely applicable. The first one is for the determination of didanosine over the range of 25.02–2502.00 ng/mL by injecting solid-phase extraction (SPE) eluate directly. The second is for the determination of betamethasone phosphate over the range of 2.51–250.60 ng/mL by injecting SPE eluate after pH adjustment. The third is for the determination of sumatriptan over the range of 0.99–99.40 ng/mL based upon SPE with high organic washing and low organic elution. The fourth is based upon automated dilution after protein precipitation for the determination of raloxifene-4'-glucuronide and raloxifene-6-glucuronide over the ranges of 2.02–202.40 ng/mL and 0.40–39.95 ng/mL, respectively.

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In Part II, we review MS ionization suppression; column, pH, and temperature selection; and system peaks and column equilibration issues associated with the use of five volatile perfluorocarboxylic acid reagents in LC.

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The authors use GPC coupled online to multiangle laser light scattering, refractive index, and ultra violet (UV) detectors for the characterization of Acacia gum (gum arabic).

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Electrophoretic techniques, such as sodium dodecyl sulphate polyacrylamide (SDS-PAGE) and isoelectric focusing (IEF) gels, have traditionally been part of release testing in the biopharmaceutical industry. However, these slab gel methods are inconvenient and irreproducible because of the staining/destaining steps used in analyte detection, the use of toxic reagents and high intra- and inter-gel effective mobility variability.

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The analysis of amines by gas chromatograph ;mass spectrometry (GC–MS) using electron ionization (EI) has always been a challenge

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In this application, we demonstrate the use of supported liquid extraction (SLE) for the extraction of beta blockers and NSAIDS from plasma compared with traditional liquid–liquid extraction. SLE was demonstrated to yield consistent LOQs using lower sample volumes.

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The analytical challenge treated in the present work consists in determining sub-ppb concentrations of low-molecular-weight amines in the presence of strongly retained cationic drugs by using ion chromatography (IC) with upstream in-line coupled-column matrix elimination (CCME).

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Glyphosate is a broad-spectrum herbicide widely used around the world. Monitoring of glyphosate in crops and water is mandated in many countries.

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Pressure-enhanced liquid chromatography (PE-LC) offers a new approach for improving selectivity for large molecule separations. Examples shown here include short oligonucleotides in ion-pairing reversed-phase (IP-RP) liquid chromatography and larger nucleic acids in ion-exchange (IEX) chromatography.

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Cytosine (chemical name 4-amino-2-hydroxypyrimidine) is a pyrimidine derivative with a hetereocyclic aromatic ring and two substituents (amine and keto groups) attached and is a polar compound of significant biological and pharmaceutical interest. In response to the intended use of bulk cytosine as a raw material in pharmaceutical manufacturing, a method for the determination of the purity of cytosine was developed.

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In HPLC method development, screening of various para-meters such as stationary phase, eluents, and temperatures is conducted to find optimal resolution. However, method development can be a time consuming and inefficient process. UHPLC technology can be applied to significantly shorten both the analysis and development times. Here we describe an integrated and ultrafast automated method scouting solution that provides fast and efficient method development processes.

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Pickering Laboratories developed an easy and sensitive method to analyze aflatoxins B1, B2, G1, G2, and ochratoxin A in hemp and hemp-containing edible products. Mycotoxins are isolated using immunoaffinity clean-up columns and analyzed with fluorescence detection. To increase sensitivity of aflatoxins B1 and G1, an in-line photochemical reactor (UVETM) is installed before the detector. This method utilizes standard HPLC equipment and allows laboratories to easily determine these mycotoxins at low ppb levels.

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Cytosine (chemical name 4-amino-2-hydroxypyrimidine) is a pyrimidine derivative with a hetereocyclic aromatic ring and two substituents (amine and keto groups) attached and is a polar compound of significant biological and pharmaceutical interest. In response to the intended use of bulk cytosine as a raw material in pharmaceutical manufacturing, a method for the determination of the purity of cytosine was developed.

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Estimating uncertainty has become one of the most important metrological concepts in analytical science over the last 15 years to such an extent that some authors consider a result useless or invalid unless it is accompanied with an uncertainty statement. This article describes how to estimate uncertainty in chromatographic analysis and how laboratories can calculate it using data from the method validation process.

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Sample preparation is an essential technique to remove unwanted matrix components prior to LC–MS-MS analysis of drugs in biological fluids. Plasma matrix components whether endogenous (salts, proteins, and phospholipids) or exogenous (dosing vehicles, e.g. PEG 400), can interfere with compounds of interest leading to regions of ion suppression or enhancement. This can lead to inaccurate quantitation and have adverse effects on sensitivity. Mixed-mode SPE provides cleaner extracts as a result of rigorous interference wash steps, afforded by the dual retention mechanism of the sorbents.

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Successful therapeutic intervention often requires chiral medicines because of the intrinsic chirality of protein drug targets, which consist of L-amino acids. Potency, efficacy, and safety can be highly dependent on the precise stereochemical geometry of the molecules. Determining the biological profile of individual enantiomers in the early stages of drug discovery is important for successful optimization towards clinical candidates. Here we demonstrate the benefits of supercritical fluid chromatography (SFC) with three chiral stationary phases exemplified by high frequency resolution of 41 out of 50 chiral derivatives of eight commonly used drug discovery scaffolds including 1,3-thiazoles, 1,3-benzothiazoles, pyranoquinolones, indoles, and leucolines.

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Inductively coupled plasma–mass spectrometry (ICP-MS) is a key analytical tool in many laboratories. It is used for elemental determinations across a wide range of analyses, including environmental, semiconductor, food safety, geological, chemical, petrochemical, nuclear, clinical, forensic, and research applications. Since the early publications during the development of ICP-MS, it has been apparent that one of the key limitations of the technique was the presence of molecular ions that overlap the preferred isotopes of several analytes. These molecular ions are typically called "polyatomic" ions, and are derived from combinations of the elements present in the plasma, the solvent and the sample matrix.