The feasibility of an electrospray coupled with a (63)Ni-differential ion mobility spectrometer (DMS) for the analysis of water samples was proven on examples of 2-hexanone, fluoroacetamide, l-nicotine and 1-phenyl-2-thiourea water solutions. The model substances were selected in order to cover the vapor pressure range of 0.3-1467 Pa. To reduce the inline humidity, which demonstrates a strong influence on the analyte compensation voltage, two units with a desolvation region lengths of 15.5 and 7 mm were examined. The counter gas (heated to 100 °C nitrogen) with flow rates of 100 mL min(-1) and 30 mL min(-1) for short and long desolvation units, respectively, was essential for the efficient reduction of humidity. The reduction of water content in the carrier gas to 2.2-2.4 g m(-3) and to 1.8-2.0 g m(-3) for the short and long desolvation unit, respectively, was achieved at an electrospray flow rate of 1000 nL min(-1). With this adjusted experimental setup, the detection of model substances in the water solutions, in the range of 0.1-50 mg L(-1), was performed. No correlation between the vapor pressure and signal area was observed. The high stability of the inline humidity, and the correspondingly stable carrier gas flow rate, were found to be essential for an acceptable reproducibility.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.talanta.2013.10.056 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Highly electroactive thiazolium [5,4-d]thiazol-2,5-dicarboxylic acid-silver electrochemiluminescent metal-organic frameworks: synthesis, properties and application in glutathione detection.
Mikrochim Acta
January 2025
Key Laboratory of Synthetic and Natural Functional Molecule Chemistry (Ministry of Education), College of Chemistry & Materials Science, Northwest University, Xi' an, 710069, PR, China.
Thiazolo[5,4-d]thiazole-2,5-dicarboxylic acid (HThz), a thiazolothiazole (TTz) derivative with carboxylic acid groups, was synthesized as a ligand for the creation of five MOFs, each associated with distinct metal ions including Ag, Mn, Co, Zn, and Cu. The cathodic electrochemiluminescence (ECL) of HThz and the resulting MOFs was investigated. HThz was found to generate ECL signals, but this process was heavily reliant on potassium persulfate (KSO) as a co-reactant.
View Article and Find Full Text PDFIon exchange chromatography of biotherapeutics: Fundamental principles and advanced approaches.
J Chromatogr A
January 2025
School of Pharmaceutical Sciences, University of Geneva, CMU - Rue Michel Servet 1, 1211 Geneva 4, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, CMU - Rue Michel Servet 1, 1211 Geneva 4, Switzerland. Electronic address:
Ion exchange chromatography (IEX) is an important analytical technique for the characterization of biotechnology-derived products, such as monoclonal antibodies (mAbs) and more recently, cell and gene therapy products such as messenger ribonucleic acid (mRNA) and adeno-associated viruses (AAVs). This review paper first outlines the basic principles and separation mechanisms of IEX for charge variant separation of biotherapeutics, and examines the different elution modes based on salt or pH gradients. It then highlights several recent trends when applying IEX for the characterization of biotechnology-derived products, including: i) the effective use of pH gradients, ii) the improvement of selectivity by using organic solvents in the mobile phase, multi-step gradients, or by combining ion pairing and ion exchange, and iii) the increase in analytical throughput using ultra-short columns or automated screening of conditions.
View Article and Find Full Text PDFLFP via Nanoscale Surface Reforming with a Tiny Minimal Amount of Conductivity-Enhancing Material.
Langmuir
January 2025
Department of Mechanical Engineering, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si, Gyeonggi-do 13120, Republic of Korea.
LiFePO (LFP) typically requires a conductive additive to improve its low ion and electron conductivity. In this study, we achieved significant enhancements in Li and electron mobility by applying a minimal amount of conductive material through a new coating process. The coin cell demonstrated an excellent capacity of 157.
View Article and Find Full Text PDFWe report the first implementation of ion mobility mass spectrometry combined with an ultra-high throughput sample introduction technology for high throughput screening (HTS). The system integrates differential ion mobility (DMS) with acoustic ejection mass spectrometry (AEMS), termed DAEMS, enabling the simultaneous quantitation of structural isomers that are the sub-strates and products of isomerase mediated reactions in intermediary metabolism. We demonstrate this potential by comparing DAEMS to a luminescence assay for the isoform of phosphoglycerate mutase (iPGM) distinctively present in pathogens offering an opportunity as a drug target for a variety of microbial and parasite borne diseases.
View Article and Find Full Text PDFDue to their self-renewal and differentiation capabilities, pluripotent stem cells hold immense potential for advancing our understanding of human disease and developing cell-based or pharmacological interventions. Realizing this potential, however, requires a thorough understanding of the basal cellular mechanisms which occur during differentiation. Lipids are critical molecules that define the morphological, biochemical, and functional role of cells.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!