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The cost of poor quality data in nucleic acid or protein work cannot be underestimated yet for some reason is overlooked. This note investigates a simple solution to the problem.

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Fluorescence spectroscopy is used to investigate museum specimen as a flexible and minimally invasive technique. The photo-physical properties of Egyptian and modern artwork pigments are presented in this application note.

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Fluorescence spectroscopy is used to investigate museum specimen as a flexible and minimally invasive technique. The photo-physical properties of Egyptian and modern artwork pigments are presented in this application note.

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A newly discovered method is described for generating gas-phase ions from volatile and nonvolatile compounds. The method, matrix-assisted ionization (MAI), is both simple and sensitive, requiring only the vacuum inherent with all mass spectrometers and a suitable matrix, eliminating the need for lasers, electric fields, nebulizing gas, and even heaters to generate gas-phase ions. MAI is applicable for the direct analysis of drugs from biological fluids and tissue without prior purification. By placing matrix only on a specific surface area of interest and exposure to the vacuum of the mass spectrometer, ions are observed from compounds within the targeted surface area of tissue exposed to the matrix solution, thus allowing rapid and simple interrogation of “features of interest.” The limit of detection for drug standards is low attomoles and clean full mass range mass spectra are obtained from low femtomoles of the drug.

Latest:

A newly discovered method is described for generating gas-phase ions from volatile and nonvolatile compounds. The method, matrix-assisted ionization (MAI), is both simple and sensitive, requiring only the vacuum inherent with all mass spectrometers and a suitable matrix, eliminating the need for lasers, electric fields, nebulizing gas, and even heaters to generate gas-phase ions. MAI is applicable for the direct analysis of drugs from biological fluids and tissue without prior purification. By placing matrix only on a specific surface area of interest and exposure to the vacuum of the mass spectrometer, ions are observed from compounds within the targeted surface area of tissue exposed to the matrix solution, thus allowing rapid and simple interrogation of “features of interest.” The limit of detection for drug standards is low attomoles and clean full mass range mass spectra are obtained from low femtomoles of the drug.

Latest:

A newly discovered method is described for generating gas-phase ions from volatile and nonvolatile compounds. The method, matrix-assisted ionization (MAI), is both simple and sensitive, requiring only the vacuum inherent with all mass spectrometers and a suitable matrix, eliminating the need for lasers, electric fields, nebulizing gas, and even heaters to generate gas-phase ions. MAI is applicable for the direct analysis of drugs from biological fluids and tissue without prior purification. By placing matrix only on a specific surface area of interest and exposure to the vacuum of the mass spectrometer, ions are observed from compounds within the targeted surface area of tissue exposed to the matrix solution, thus allowing rapid and simple interrogation of “features of interest.” The limit of detection for drug standards is low attomoles and clean full mass range mass spectra are obtained from low femtomoles of the drug.

Latest:

A newly discovered method is described for generating gas-phase ions from volatile and nonvolatile compounds. The method, matrix-assisted ionization (MAI), is both simple and sensitive, requiring only the vacuum inherent with all mass spectrometers and a suitable matrix, eliminating the need for lasers, electric fields, nebulizing gas, and even heaters to generate gas-phase ions. MAI is applicable for the direct analysis of drugs from biological fluids and tissue without prior purification. By placing matrix only on a specific surface area of interest and exposure to the vacuum of the mass spectrometer, ions are observed from compounds within the targeted surface area of tissue exposed to the matrix solution, thus allowing rapid and simple interrogation of “features of interest.” The limit of detection for drug standards is low attomoles and clean full mass range mass spectra are obtained from low femtomoles of the drug.

Latest:

A newly discovered method is described for generating gas-phase ions from volatile and nonvolatile compounds. The method, matrix-assisted ionization (MAI), is both simple and sensitive, requiring only the vacuum inherent with all mass spectrometers and a suitable matrix, eliminating the need for lasers, electric fields, nebulizing gas, and even heaters to generate gas-phase ions. MAI is applicable for the direct analysis of drugs from biological fluids and tissue without prior purification. By placing matrix only on a specific surface area of interest and exposure to the vacuum of the mass spectrometer, ions are observed from compounds within the targeted surface area of tissue exposed to the matrix solution, thus allowing rapid and simple interrogation of “features of interest.” The limit of detection for drug standards is low attomoles and clean full mass range mass spectra are obtained from low femtomoles of the drug.

Latest:

A newly discovered method is described for generating gas-phase ions from volatile and nonvolatile compounds. The method, matrix-assisted ionization (MAI), is both simple and sensitive, requiring only the vacuum inherent with all mass spectrometers and a suitable matrix, eliminating the need for lasers, electric fields, nebulizing gas, and even heaters to generate gas-phase ions. MAI is applicable for the direct analysis of drugs from biological fluids and tissue without prior purification. By placing matrix only on a specific surface area of interest and exposure to the vacuum of the mass spectrometer, ions are observed from compounds within the targeted surface area of tissue exposed to the matrix solution, thus allowing rapid and simple interrogation of “features of interest.” The limit of detection for drug standards is low attomoles and clean full mass range mass spectra are obtained from low femtomoles of the drug.

Latest:

A newly discovered method is described for generating gas-phase ions from volatile and nonvolatile compounds. The method, matrix-assisted ionization (MAI), is both simple and sensitive, requiring only the vacuum inherent with all mass spectrometers and a suitable matrix, eliminating the need for lasers, electric fields, nebulizing gas, and even heaters to generate gas-phase ions. MAI is applicable for the direct analysis of drugs from biological fluids and tissue without prior purification. By placing matrix only on a specific surface area of interest and exposure to the vacuum of the mass spectrometer, ions are observed from compounds within the targeted surface area of tissue exposed to the matrix solution, thus allowing rapid and simple interrogation of “features of interest.” The limit of detection for drug standards is low attomoles and clean full mass range mass spectra are obtained from low femtomoles of the drug.

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The purpose of this study was the development of various analytical MS methods to investigate the chemical composition of e-liquids used in electronic cigarettes and characterize their quality. Low-quality nicotine (the main active compound), glycerol, propylene glycol (solvents), or flavors could greatly increase the toxicity. The search of alkaloid contaminants of nicotine was performed by LC–MS-MS after a deep study of fragmentation pathways by high resolution ESI-MS. A fully validated method for quantitation of organic polar impurities such as cotinine, anabasine, myosmine, nornicotine, and N-nitroso-nornicotine and nicotine itself was developed using MS coupled to UHPLC. To evaluate organic volatile toxicants, headspace from e-cigarette refill liquids was sampled by SPME to perform GC–MS analysis. Finally, heavy metal residues as inorganic toxicants were determined by ICP-MS after simple dilution. A number of cases of contamination by metals (mainly arsenic) was detected.

Latest:

The purpose of this study was the development of various analytical MS methods to investigate the chemical composition of e-liquids used in electronic cigarettes and characterize their quality. Low-quality nicotine (the main active compound), glycerol, propylene glycol (solvents), or flavors could greatly increase the toxicity. The search of alkaloid contaminants of nicotine was performed by LC–MS-MS after a deep study of fragmentation pathways by high resolution ESI-MS. A fully validated method for quantitation of organic polar impurities such as cotinine, anabasine, myosmine, nornicotine, and N-nitroso-nornicotine and nicotine itself was developed using MS coupled to UHPLC. To evaluate organic volatile toxicants, headspace from e-cigarette refill liquids was sampled by SPME to perform GC–MS analysis. Finally, heavy metal residues as inorganic toxicants were determined by ICP-MS after simple dilution. A number of cases of contamination by metals (mainly arsenic) was detected.

Latest:

The purpose of this study was the development of various analytical MS methods to investigate the chemical composition of e-liquids used in electronic cigarettes and characterize their quality. Low-quality nicotine (the main active compound), glycerol, propylene glycol (solvents), or flavors could greatly increase the toxicity. The search of alkaloid contaminants of nicotine was performed by LC–MS-MS after a deep study of fragmentation pathways by high resolution ESI-MS. A fully validated method for quantitation of organic polar impurities such as cotinine, anabasine, myosmine, nornicotine, and N-nitroso-nornicotine and nicotine itself was developed using MS coupled to UHPLC. To evaluate organic volatile toxicants, headspace from e-cigarette refill liquids was sampled by SPME to perform GC–MS analysis. Finally, heavy metal residues as inorganic toxicants were determined by ICP-MS after simple dilution. A number of cases of contamination by metals (mainly arsenic) was detected.

Latest:

The purpose of this study was the development of various analytical MS methods to investigate the chemical composition of e-liquids used in electronic cigarettes and characterize their quality. Low-quality nicotine (the main active compound), glycerol, propylene glycol (solvents), or flavors could greatly increase the toxicity. The search of alkaloid contaminants of nicotine was performed by LC–MS-MS after a deep study of fragmentation pathways by high resolution ESI-MS. A fully validated method for quantitation of organic polar impurities such as cotinine, anabasine, myosmine, nornicotine, and N-nitroso-nornicotine and nicotine itself was developed using MS coupled to UHPLC. To evaluate organic volatile toxicants, headspace from e-cigarette refill liquids was sampled by SPME to perform GC–MS analysis. Finally, heavy metal residues as inorganic toxicants were determined by ICP-MS after simple dilution. A number of cases of contamination by metals (mainly arsenic) was detected.

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We have developed a range of analytical workflows using mass spectrometry, in a regulated environment, to support pharmaceutical companies in the development and control of their monoclonal antibodies (mAbs) and antibody-drug conjugates (ADCs). High-resolution mass spectrometry is a powerful tool for the analysis of antibodies, but is not readily compatible with a number of chromatographic techniques using high-salt mobile phases. Herein, we present the development and use for marketed mAbs and ADCs of 2D LC–MS via an online desalting step. We demonstrate the importance of such a setup for the determination of drug:antibody ratio (DAR), and the analysis of molecularity, fragmentation, and charge variants (deamidation, oxidation), notably under stress conditions. We discuss the advantages of 2D LC–MS in a regulated environment.

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A rapid, accurate, and precise method for the quantification of trypsin inhibitor activity was evaluated. The method utilizes alpha hydroxyl acid capped oligo-lysines [hydroxy acid (Lys)n] or alpha hydroxyl acid capped oligo-lysines-methionine [hydroxy acid (Lys-Met)] as substrates. Hydrolysis of the oligopeptides yields unique chemical residues that were readily quantified with electrospray–mass spectrometry (ESI-MS). Accuracy and precision of the approach compared favorably with that of the standard test method.

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BaySpec’s PeakFinderTM Raman video probe combines a flexible fiber optic probe with microscope objectives allowing sampling down to several microns. Combined with various benchtop Raman spectrometers, the Raman video probe is a unique micro-Raman system available in 532, 785 or 1064nm excitation and various microscope objectives offering unprecedented flexibility and versatility.

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BaySpec’s PeakFinderTM Raman video probe combines a flexible fiber optic probe with microscope objectives allowing sampling down to several microns. Combined with various benchtop Raman spectrometers, the Raman video probe is a unique micro-Raman system available in 532, 785 or 1064nm excitation and various microscope objectives offering unprecedented flexibility and versatility.

Latest:

BaySpec’s PeakFinderTM Raman video probe combines a flexible fiber optic probe with microscope objectives allowing sampling down to several microns. Combined with various benchtop Raman spectrometers, the Raman video probe is a unique micro-Raman system available in 532, 785 or 1064nm excitation and various microscope objectives offering unprecedented flexibility and versatility.

Latest:

Despite all of the recent advances in analytical technologies dedicated to biotherapeutics, accurate protein quantification remains a challenge for the biopharmaceutical industry. UV spectrophotometry is commonly used for batch testing, but it requires the knowledge of the extinction coefficient of the protein, whose experimental determination requires the accurate concentration of a reference standard obtained by an absolute quantification method. To address the need for a fast analytical method capable of accurately quantifying a protein without any specific reference substance, an isotope dilution ICP-MS method was developed and validated, based on sulfur determination, allowing very accurate determination of a single protein in solution after microwave digestion.

Latest:

We have developed a range of analytical workflows using mass spectrometry, in a regulated environment, to support pharmaceutical companies in the development and control of their monoclonal antibodies (mAbs) and antibody-drug conjugates (ADCs). High-resolution mass spectrometry is a powerful tool for the analysis of antibodies, but is not readily compatible with a number of chromatographic techniques using high-salt mobile phases. Herein, we present the development and use for marketed mAbs and ADCs of 2D LC–MS via an online desalting step. We demonstrate the importance of such a setup for the determination of drug:antibody ratio (DAR), and the analysis of molecularity, fragmentation, and charge variants (deamidation, oxidation), notably under stress conditions. We discuss the advantages of 2D LC–MS in a regulated environment.

Latest:

A rapid, accurate, and precise method for the quantification of trypsin inhibitor activity was evaluated. The method utilizes alpha hydroxyl acid capped oligo-lysines [hydroxy acid (Lys)n] or alpha hydroxyl acid capped oligo-lysines-methionine [hydroxy acid (Lys-Met)] as substrates. Hydrolysis of the oligopeptides yields unique chemical residues that were readily quantified with electrospray–mass spectrometry (ESI-MS). Accuracy and precision of the approach compared favorably with that of the standard test method.

Latest:

Despite all of the recent advances in analytical technologies dedicated to biotherapeutics, accurate protein quantification remains a challenge for the biopharmaceutical industry. UV spectrophotometry is commonly used for batch testing, but it requires the knowledge of the extinction coefficient of the protein, whose experimental determination requires the accurate concentration of a reference standard obtained by an absolute quantification method. To address the need for a fast analytical method capable of accurately quantifying a protein without any specific reference substance, an isotope dilution ICP-MS method was developed and validated, based on sulfur determination, allowing very accurate determination of a single protein in solution after microwave digestion.

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Miniature X-ray sources reached the development level that is appropriate for their use in the handheld and portable X-Ray diffraction (XRD) instruments. This note describes the application of X-ray sources for the residual stress measurements using XRD.

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XRF is a key quality control technique for cement production. We look at results from two types of portland cement prepared as pressed pellets.

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This application note describes the measurement of food macronutrients by diamond attenuated total reflectance (ATR) mid infrared spectroscopy. Specific examples include the measurement of sugar content of grapes (grape juice) and the measurement of fats in cheese, chocolate and milk.

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This application note describes the measurement of food macronutrients by diamond attenuated total reflectance (ATR) mid infrared spectroscopy. Specific examples include the measurement of sugar content of grapes (grape juice) and the measurement of fats in cheese, chocolate and milk.

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Monoclonal antibodies (mAbs) have been increasingly used as biotherapeutic agents and a number of new mAbs are currently in the drug pipeline. Over the next five years the patent on at least nine major biotherapeutic monoclonal antibodies will expire, opening the door for development and marketing of generic forms known as Biosimilars. In this paper a review of the central role mass spectrometry coupled to liquid chromatography plays in characterizing these antibodies is presented. Contemporary top down and middle-up approaches using mass spectrometry and various novel separation techniques to measure the intact masses of mAbs and their subunits or domains are highlighted. Example data of an innovator mAb, Humira (adalimumab) are presented showing the identities and relative abundances of the isoforms associated with this mAb. Similarly the current state of classical peptide mapping using reversed-phase chromatography and tandem mass spectrometry with scan- dependent acquisition is briefly reviewed. Novel approaches that speed analysis and provide information on post translational modifications, glycosylation, and disulfide mapping are discussed. Example data of stressed and unstressed samples of adalimumab are also presented to demonstrate peptide mapping data and modifications to the antibody. Lastly, the current use of mass spectrometry in glycoprofiling of mAbs is reviewed. Example glycan data for adalimumab generated by a novel labeling scheme and sensitive to detection by both fluorescence and mass spectrometry will be presented.

Latest:

Monoclonal antibodies (mAbs) have been increasingly used as biotherapeutic agents and a number of new mAbs are currently in the drug pipeline. Over the next five years the patent on at least nine major biotherapeutic monoclonal antibodies will expire, opening the door for development and marketing of generic forms known as Biosimilars. In this paper a review of the central role mass spectrometry coupled to liquid chromatography plays in characterizing these antibodies is presented. Contemporary top down and middle-up approaches using mass spectrometry and various novel separation techniques to measure the intact masses of mAbs and their subunits or domains are highlighted. Example data of an innovator mAb, Humira (adalimumab) are presented showing the identities and relative abundances of the isoforms associated with this mAb. Similarly the current state of classical peptide mapping using reversed-phase chromatography and tandem mass spectrometry with scan- dependent acquisition is briefly reviewed. Novel approaches that speed analysis and provide information on post translational modifications, glycosylation, and disulfide mapping are discussed. Example data of stressed and unstressed samples of adalimumab are also presented to demonstrate peptide mapping data and modifications to the antibody. Lastly, the current use of mass spectrometry in glycoprofiling of mAbs is reviewed. Example glycan data for adalimumab generated by a novel labeling scheme and sensitive to detection by both fluorescence and mass spectrometry will be presented.