In drug discovery, determining information about the extent of metabolism and the elucidation of metabolite structures is a vital step for lead optimization and drug scaffold refinement. The identification and characterization of metabolites plays an important role in both the drug discovery and development phases, as unsuitable pharmacokinetics (bioavailability and drug distribution), toxicity, and adverse drug reactions might be linked to metabolic instability. Historically, metabolite identification was carried out after a compound had been chosen for drug development. However, to reduce candidate failures attributed to toxicity effects, many pharmaceutical companies now conduct these experiments in the earliest phases of candidate drug selection.
In this study, far-UV CD spectra of eight different mammalian serum albumins were measured repeatedly using automated CD spectroscopy. Two independent methods of normalizing the CD data were used to eliminate the need for accurate knowledge of protein concentration or extinction coefficient. The normalized far-UV data, representative of secondary structure, were compared to determine if there were statistically significant differences between samples. The two normalization methods agreed in every case, increasing confidence in the results.
This comprehensive peer-reviewed set of more than 600 definitions covers topics of interest for the biopharmaceutical and gene therapy subjects of genetics, therapeutics, drug development, clinical medicine, and the analytical science tools used for characterization of drugs. This glossary serves as a helpful reference to both novice and advanced scientists, engineers, and business executives involved with biopharmaceuticals and gene therapy technologies. Online sources of information for topics covered in this guide are also included for additional insights.
This article discusses the analysis of a wide range of CWAs at current exposure limits and describes a number of recent beneficial developments in TD and associated analytical technologies for the identification and quantification of CWAs at these levels.
This application note demonstrates using ATR to examine the changes in surface orientation as a function of the distance from the injection point or gate.
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By switching to a Raptor C18 column, labs can process more samples per hour while still meeting fluorochemical method requirements.
In this study, general extract screening of food storage materials was done with nontargeted analytical methods to understand what analytes could potentially leach into food or beverages. GC and mass spectral deconvolution effectively separated analytes within the complex mixture and TOF-MS provided full mass range spectral data for identification. This workflow can be used for confident characterization of components present as extractables from food packaging materials.
Detrimental health effects of a group of brominated flame retardants, polybrominated diphenyl ethers (PBDEs), have been recognized recently, but only after their wide usage and consequently, global dispersal. Of the possible 209 PBDE congeners, 39 (varying in degree of bromination from mono to deca) have been identified previously in the three common technical mixtures. Additional congeners, presumably debromination products of the fully brominated decabromodiphenyl ether (BDE-209), also have been reported in biotic and abiotic environments. However, costly analytical standards are needed to confirm their identification. In addition, the most widely used identification approach, electron ionization (EI) mass spectrometry (MS), primarily produces spectra indicating only homologue grouping (for example, hepta-BDE). Without specific compound identification, full assessment of toxicological consequences of PBDE burdens is impeded. It has been reported previously that electron-capture negative ionization (ECNI),..
The authors demonstrate the capacity to separate petroleum-derived molecules having the same nominal mass in the mobility dimension using IM-MS spectrometry.
Combined with appropriate selection of instrument components to reduce the sulfur background, ICP-MS using MS/MS with oxygen reaction cell gas can provide accurate low-level analysis of sulfur and sulfur isotope ratios in aqueous and organic matrices. This is useful in applications in life science, clinical research, pharmaceutical development, food safety, environmental monitoring, geochemistry, and petrochemistry.
Acquisition and interpretation of a spectra database for ICP-AES analysis are described. The aim is the selection of nanometer-wide spectral windows containing several elements and several lines per element, so as to perform multiline analysis. An automatic line assignment procedure has been used. Information such as wavelength, sensitivity, line width, limit of detection, and level of detector saturation are stored. Filtering procedures are used for line selection, taking into account concentrations and possible spectral interferences.
Multiple reflection attenuated total reflection FT-IR accessory allows for protein analysis of strongly IR-absorbing samples, such as aqueous solutions.
Tiny Wearable Raman Spectrometers for Direct and SERS Detections for the Real World!
Raman confocal spectroscopy is increasingly being applied for the analysis of embedded contaminants within materials. A non-contact, non-destructive analysis method, Raman spectroscopy requires very little sample preparation, has greater spatial resolution compared to FT-IR microscopy and the confocal analysis method allows visualization of materials within a clear sample matrix. This paper will investigate the analysis of an embedded contaminant within a polymer matrix on a glass substrate.
Discover the superior performance of the AccuTOF™ GC-Alpha, designed to deliver ultimate performance and functionality for complex GC-MS analysis in industrial applications.
One of the most powerful aspects of Raman microscopy is the capability to do confocal analysis of features inside of a sample without having to prepare or damage the sample to get the important spectral information.
The authors discuss the use of near-infrared spectroscopy to determine the age of a bloodstain, which can be critical in helping establish when a crime was committed.
A new infrared spectroscopy technique, microfluidic modulation spectroscopy (MMS), delivers reproducible protein characterization over close to four orders of magnitude in protein concentration (from 0.1 to 200 mg/mL). This technique characterizes samples from the earliest stages of development through to manufacture.
A person-portable gas chromatography–mass spectrometry (GC–MS) system employing a toroidal ion trap mass spectrometry (TMS) detector was used to analyze chemical threat related compounds. Introduction of analytes into the heated injector of the instrument was by solid-phase microextraction (SPME), and fast resistive heating of a low thermal mass (LTM) gas chromatography column assembly provided rapid analysis times. Methodology for positive identification of chemical threats can combine chromatographic retention time, comparison to traditional electron ionization mass spectral libraries, and observation of expected pseudomolecular ions produced through self-chemical ionization. Methods are discussed for sampling by SPME with GC–MS analysis in the field to measure airborne analyte concentrations.
A prerequisite for a successful biotherapeutic formulation is one where the protein is stable and correctly folded. The new technique of dynamic multi-mode spectroscopy (DMS) was used to study the stability of a monoclonal antibody biotherapeutic formulated in acetate and lactate buffers. The samples were measured several times over a period of weeks and it became apparent that the antibody behaved differently as it aged in the two formulations, with the lactate formulation imparting greater robustness than the acetate.
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.
Spectroscopy's annual overview of new instrumentation presented at the PittCon conference.
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.
Traditionally the analysis of volatile liquids by FTIR spectroscopy has always entailed a sealed fixed pathlength cell.
The United States Food and Drug Administration (FDA) is using Remote Interactive Evaluations (RIE) to assess regulatory compliance, review submission material, or determine the timing of future inspections. Here, we look at some of the impacts of RIE on GxP laboratories. Although RIE is voluntary, is this an offer that you cannot refuse?
A Look at Spectroscopists' Incomes and Attitudes about Their Jobs