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Excited state dynamics provides an intrinsic molecular contrast of samples examined. These dynamics can be monitored by pump probe spectroscopy which measures the change in transmission of a probe beam induced by a pump beam. With superior detection sensitivity, chemical specificity and spatial-temporal resolution, pump probe microscopy is an emerging tool for functional imaging of non-fluorescent chromophores and nanomaterials. This article reviews the basic principle, instrumentation strategy, data analysis methods, and applications of pump probe microscopy. A brief outlook is provided.

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This year’s honoree, Megan Thielges, is a pioneer in the development of vibrational probes for use with 2D IR spectroscopy, to reveal new information about the structures and dynamics of proteins.

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Excited state dynamics provides an intrinsic molecular contrast of samples examined. These dynamics can be monitored by pump probe spectroscopy which measures the change in transmission of a probe beam induced by a pump beam. With superior detection sensitivity, chemical specificity and spatial-temporal resolution, pump probe microscopy is an emerging tool for functional imaging of non-fluorescent chromophores and nanomaterials. This article reviews the basic principle, instrumentation strategy, data analysis methods, and applications of pump probe microscopy. A brief outlook is provided.

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A method is illustrated for the simultaneous analysis of ethyl glucuronide and ethyl sulfate in human urine samples.

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Key Issues: Sampling flexibility of Raman enables in-process analysis of solids, turbid media, liquids, and gases Large volumetric Raman provide representative sampling of heterogenous solids

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The US EPA monitors a variety of chemicals in water that may cause harm to humans or wildlife to minimize exposure.

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With the recent legalization of cannabis in several states, there is a growing need for robust, reliable, and cost-effective analytical methods to facilitate routine testing for potency and contaminants. Here we present an LC–MS/MS method that uses the budget-friendly SCIEX Triple Quad 3500 LC–MS/MS system for the simultaneous detection and quantification of cannabinoids, pesticides, and mycotoxins in cannabis products using the Scheduled MRM algorithm.

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This article reviews recent advances in the application of Transmission Raman Spectroscopy (TRS) to pharmaceutical analysis. The TRS technique overcomes subsampling limitations of conventional Raman spectroscopy and enables rapid non-invasive volumetric analysis of intact pharmaceutical tablets and capsules in a quantitative manner with relevance to quality and process control applications. Although only recently introduced to this area its uptake and the breadth of applications are rapidly growing with regulatory approvals for use of this technology in quality control of manufactured pharmaceutical products recently being granted.

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This article reviews recent advances in the application of Transmission Raman Spectroscopy (TRS) to pharmaceutical analysis. The TRS technique overcomes subsampling limitations of conventional Raman spectroscopy and enables rapid non-invasive volumetric analysis of intact pharmaceutical tablets and capsules in a quantitative manner with relevance to quality and process control applications. Although only recently introduced to this area its uptake and the breadth of applications are rapidly growing with regulatory approvals for use of this technology in quality control of manufactured pharmaceutical products recently being granted.

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Systematic toxicological analysis is an important step in medicolegal investigations of death, poisoning, and drug use. The primary goal is the detection and confirmation of potentially toxic compounds in evidence. This article describes a workflow using nontargeted liquid chromatography–tandem mass spectrometry (LC–MS/MS) for reliable compound identification.

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Antibody drug conjugates (ADCs) are an emerging category of biotherapeutic products based on monoclonal antibodies (mAbs) coupled to powerful cytotoxic drugs. The production of ADCs entails the formation of species with different number of conjugates drugs. The heterogeneity of ADCs species add to the complexity originating from the mAbs microvariability. Sheathless capillary electrophoresis-mass spectrometry (sheathless CE-MS) using complementary approaches was used to perform a detail characterization of brentuximab vedotin (Adcetris, Seattle Genetics). Sheathless CE-MS instrument used as nanoESI infusion platform was involved to perform the intact and middle-up analysis in native MS conditions. The nanoESI infusion approaches enabled estimation of the average drug to antibody ratio (DAR) alongside to drug load distribution. Sheathless CZE-MS/MS method developed was used to obtain from a single injection the characterization of the amino acid sequence with complete sequence coverage. In addition glycosylation and drug-loaded peptides could be identified from MS/MS spectra revealing robust information regarding their localizations and abundances. Drug-loaded peptide fragmentation mass spectra study demonstrated drug-specific fragments reinforcing the identifications confidence. Results reveal the ability of sheathless CZE-MS/MS method to characterize ADCs primary structure in a single experiment.

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The method presented here allows for the accurate, precise, and robust speciation, profiling, and quantification of cannabinoids in hemp oil extracts and commercial cannabinoid products for research and development laboratories.

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The method presented here allows for the accurate, precise, and robust speciation, profiling, and quantification of cannabinoids in hemp oil extracts and commercial cannabinoid products for research and development laboratories.

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The method presented here allows for the accurate, precise, and robust speciation, profiling, and quantification of cannabinoids in hemp oil extracts and commercial cannabinoid products for research and development laboratories.

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The method presented here allows for the accurate, precise, and robust speciation, profiling, and quantification of cannabinoids in hemp oil extracts and commercial cannabinoid products for research and development laboratories.

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In this review article, the editors of Spectroscopy break down the most recent research and trends using inductively coupled plasma mass spectrometry (ICP-MS).

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Headspace SPME combined with GC–MS for the qualitative and quantitative analysis of terpenes in cannabis offers several advantages compared to other methods. It does not require the use of organic solvents, does not coextract matrix, and provides additional means of peak identification and purity using spectral data. It is also a nondestructive method.

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Well-established techniques used by the food safety industry, such as QuEChERS sample preparation followed by LC–MS/MS for the analysis of multiresidue pesticides, are evaluated for use with cannabis plant material.We evaluated a modified QuEChERS LC-MS/MS method for analysis of multiresidue pesticides.

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Well-established techniques used by the food safety industry, such as QuEChERS sample preparation followed by LC–MS/MS for the analysis of multiresidue pesticides, are evaluated for use with cannabis plant material.We evaluated a modified QuEChERS LC-MS/MS method for analysis of multiresidue pesticides.

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Well-established techniques used by the food safety industry, such as QuEChERS sample preparation followed by LC–MS/MS for the analysis of multiresidue pesticides, are evaluated for use with cannabis plant material.We evaluated a modified QuEChERS LC-MS/MS method for analysis of multiresidue pesticides.

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The method described here allows for the simultaneous analysis of 47 pesticides and five mycotoxins in cannabis in one simple QuEChERS procedure. This simple method is designed for implementation in start-up laboratories and in established laboratories that wish to streamline their sample preparation process, decrease solvent usage, and obtain accurate and fast results.

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The method described here allows for the simultaneous analysis of 47 pesticides and five mycotoxins in cannabis in one simple QuEChERS procedure. This simple method is designed for implementation in start-up laboratories and in established laboratories that wish to streamline their sample preparation process, decrease solvent usage, and obtain accurate and fast results.

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These tables and figure are supplementary information to the article "Optimized ICP-MS Analysis of Elemental Impurities in Semiconductor-Grade Hydrochloric Acid."

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A simple method for extraction and concentration of trace organic compounds found in water for gas chromatography-mass spectrometry (GC-MS) analysis was developed. The method used 25 and 45 mL glass vials with a 5-10 µm thick polymer coatings for extraction of analytes from 20 and 40 mL water samples, respectively. Analytes were subsequently transferred from the polymer coating into an organic solvent, which was reduced in volume to 200-400 µL for analysis. A 10-20 µL sample from the vial was transferred to a tiny coiled stainless steel wire filament using a micro-syringe, or by dipping the coil into the sample. After air evaporation of the solvent, the coil was inserted into the heated injection port of a portable GC-MS system where the analytes were desorbed. Injection using the coiled wire filament eliminated sample discrimination of high boiling point compounds, and minimized system contamination caused by sample matrix residues. The GC-MS contained a new resistively heated column bundle that allowed elution of low-volatility compounds in less than 4 min. Analyses of organochlorine pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyl congeners, pyrethroid insecticides, phthalate esters, and n-alkanes in water and wastewater samples were accomplished for low ppb concentrations in less than 10 min total analysis time.

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A simple method for extraction and concentration of trace organic compounds found in water for gas chromatography-mass spectrometry (GC-MS) analysis was developed. The method used 25 and 45 mL glass vials with a 5-10 µm thick polymer coatings for extraction of analytes from 20 and 40 mL water samples, respectively. Analytes were subsequently transferred from the polymer coating into an organic solvent, which was reduced in volume to 200-400 µL for analysis. A 10-20 µL sample from the vial was transferred to a tiny coiled stainless steel wire filament using a micro-syringe, or by dipping the coil into the sample. After air evaporation of the solvent, the coil was inserted into the heated injection port of a portable GC-MS system where the analytes were desorbed. Injection using the coiled wire filament eliminated sample discrimination of high boiling point compounds, and minimized system contamination caused by sample matrix residues. The GC-MS contained a new resistively heated column bundle that allowed elution of low-volatility compounds in less than 4 min. Analyses of organochlorine pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyl congeners, pyrethroid insecticides, phthalate esters, and n-alkanes in water and wastewater samples were accomplished for low ppb concentrations in less than 10 min total analysis time.

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Ion mobility mass spectrometry (IMMS) is a two-dimensional technique that allows separation of ionized molecules based on molecular size, shape, and mass‑to‑charge ratio (m/z). It has rapidly become a valuable application for analyzing isomeric compounds in a complex matrix (e.g., proteomic and lipidomic samples) or complex mixtures of structurally related and isobaric analytes (e.g., oil samples or polymer blends). IMMS was investigated as a possible technique to compare purported generic products with Copaxone®, a drug for treating relapsing‑remitting multiple sclerosis, which contains a very complex mixture of synthetic peptides. The analysis was performed on 15 randomly chosen batches of Copaxone® and 5 batches of purported generics that are marketed drugs in their country of origin. All samples were compared to a reference batch of Copaxone® (P53961) using Waters HDMS Compare software. The analysis produced heat maps that highlighted significant intensity differences in peptides at various m/z and drift times. A quantitative assessment of these heat maps was also performed by summing all the pixel values to produce a total pixel value (TPV). While the average TPV for the Copaxone® batches was 510811, the TPVs of the purported generics were 8-13 fold higher (2301682 to 4276572).

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Quantum chemistry is capable of calculating a wide range of electronic and thermodynamic properties of interest to a chemist or physicist. Calculations can be used both to predict the results of future experiments and to aid in the interpretation of existing results. This paper will demonstrate some examples where quantum chemistry can aid in the development of mass spectrometric methods. Gas-phase electron affinities (EAs) have been difficult to determine experimentally, so the literature values are often not reliable. Computational methods using quantum chemistry have allowed the compilation of a self-consistent database for the EAs of polynuclear aromatic compounds. Likewise, proton affinities (PAs) and ionization potentials (IPs) have been calculated and compared favorably with experimental results for these molecules.

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Ion mobility mass spectrometry (IMMS) is a two-dimensional technique that allows separation of ionized molecules based on molecular size, shape, and mass‑to‑charge ratio (m/z). It has rapidly become a valuable application for analyzing isomeric compounds in a complex matrix (e.g., proteomic and lipidomic samples) or complex mixtures of structurally related and isobaric analytes (e.g., oil samples or polymer blends). IMMS was investigated as a possible technique to compare purported generic products with Copaxone®, a drug for treating relapsing‑remitting multiple sclerosis, which contains a very complex mixture of synthetic peptides. The analysis was performed on 15 randomly chosen batches of Copaxone® and 5 batches of purported generics that are marketed drugs in their country of origin. All samples were compared to a reference batch of Copaxone® (P53961) using Waters HDMS Compare software. The analysis produced heat maps that highlighted significant intensity differences in peptides at various m/z and drift times. A quantitative assessment of these heat maps was also performed by summing all the pixel values to produce a total pixel value (TPV). While the average TPV for the Copaxone® batches was 510811, the TPVs of the purported generics were 8-13 fold higher (2301682 to 4276572).

Latest:

Quantum chemistry is capable of calculating a wide range of electronic and thermodynamic properties of interest to a chemist or physicist. Calculations can be used both to predict the results of future experiments and to aid in the interpretation of existing results. This paper will demonstrate some examples where quantum chemistry can aid in the development of mass spectrometric methods. Gas-phase electron affinities (EAs) have been difficult to determine experimentally, so the literature values are often not reliable. Computational methods using quantum chemistry have allowed the compilation of a self-consistent database for the EAs of polynuclear aromatic compounds. Likewise, proton affinities (PAs) and ionization potentials (IPs) have been calculated and compared favorably with experimental results for these molecules.