Multifrequency Nanomechanical Mass Spectrometer Prototype for Measuring Viral Particles Using Optomechanical Disk Resonators

Nanomechanical mass spectrometry allows characterization of analytes with broad mass range, from small proteins to bacterial cells, and with unprecedented mass sensitivity. In this work, we show a novel multifrequency nanomechanical mass spectrometer prototype designed for focusing, guiding and soft-landing of nanoparticles and viral particles...

A new approach combining analytical methods for workplace exposure assessment of inhalable multi-walled carbon nanotubes

To date there is no consensus about the most appropriate analytical method for measuring carbon nanotubes (CNTs), hampering the assessment and limiting the comparison of data. The goal of this study is to develop an approach for the assessment of the level and nature of inhalable multi-wall CNTs (MWCNTs) in an actual workplace setting by...

The advantage of laser-capture microdissection over whole tissue analysis in proteomic profiling studies

Characterization of titanium dioxide nanoparticles in food products: Analytical methods to define nanoparticles

Titanium dioxide (TiO2) is a common food additive used to enhance the white color, brightness, and sometimes flavor of a variety of food products. In this study 7 food grade TiO2 materials (E171), 24 food products, and 3 personal care products were investigated for their TiO 2 content and the number-based size distribution of TiO2 particles...

Bioconversion of red ginseng saponins in the gastro-intestinal tract in vitro model studied by high-performance liquid chromatography-high resolution Fourier transform ion cyclotron resonance mass spectrometry

A high-performance liquid chromatography-high resolution Fourier transform ion cyclotron resonance mass spectrometry (HPLC-FTICR-MS) method was developed to investigate the metabolism of ginsenosides in in vitro models of the gastro-intestinal tract. The metabolites were identified by high-resolution tandem mass spectrometry. Degradation and...

Alkaloid profiling of the Chinese herbal medicine Fuzi by combination of matrix-assisted laser desorption ionization mass spectrometry with liquid chromatography-mass spectrometry

A matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) method was developed for the high throughput and robust qualitative profiling of alkaloids in Fuzi-the processed lateral roots of the Chinese herbal medicine Aconitum carmichaeli Debx (A. carmichaeli). After optimization, powdered roots - without any further sample...

Quantitative profiling of bile acids in biofluids and tissues based on accurate mass high resolution LC-FT-MS: Compound class targeting in a metabolomics workflow

We report a sensitive, generic method for quantitative profiling of bile acids and other endogenous metabolites in small quantities of various biological fluids and tissues. The method is based on a straightforward sample preparation, separation by reversed-phase high performance liquid-chromatography mass spectrometry (HPLC-MS) and electrospray...

Validation of transferability of DBA derivatization and LC-MS/MS determination method for isocyanates via an interlaboratory comparison

An adapted method for the quantitative determination of isocyanates in air was implemented and validated in-house. The method was based on air sampling using an impinger flask containing di-n-butylamine (DBA) in toluene and a glass fibre filter in series. The DBA derivatives were determined using liquid chromatography and tandem mass...

Matrix-assisted laser desorption/ionisation aerosol time-of-flight mass spectrometry for the anaysis of bioaerosols: development of a fast detector for airborne biological pathogens

A new aerosol time-of-flight mass spectrometer (ATOFMS) was developed for the near real-time analysis of single bioaerosol particles. The system combines ATOFMS with laser-induced fluorescence selection and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The influences of laser power and sample preparation on the quality...

The role of analytical sciences in medical systems biology

Medical systems biology has generated widespread interest because of its bold conception and exciting potential, but the field is still in its infancy. Although there has been tremendous progress achieved recently in generating, integrating and analysing data in the medical and pharmaceutical field, many challenges remain, especially with...

Generic solid phase extraction-liquid chromatography-tandem mass spectrometry method for fast determination of drugs in biological fluids

A generic method was developed for the fast determination of a wide range of drugs in serum or plasma. The methodology comprises generic solid-phase extraction, on-line coupled to gradient HPLC with tandem mass spectrometric detection (SPE-LC-MS/MS). The individual components of the SPE-LC-MS/MS system were optimized in an integrated approach to...

The development of a specific detector for biological warfare agent particles

This paper describes the latest achievements in the development of a new rapid detector for biological warfare agents (BWA). The system uses aerodynamic particle sizing and matrix-assisted laser desorption/ionisation aerosol time-of-flight mass spectrometry (MALDI ATOFMS) to analyse individual aerosol particles sampled directly from the...

Use of biosensors for rapid drug residue analysis without sample deconjugation or clean-up: A possible way forward

The drug salbutamol (SBL) is a β-agonist that may be used illegally as an animal growth promoter. SBL is also a good example of a drug which is excreted in the form of glucuronides and sulfates. Such metabolites cause complexities in analysing for the presence of drug residues. In the majority of cases a process of deconjugation and sample clean...

Electron ionization mass spectrometry of curcumin analogues: An olefin metathesis reaction in the fragmentation of radical cations

The natural compound curcumin, used in cosmetics, traditional medicines and as a spice in food, is known as a multi-factorial anti-inflammatory agent. To study the anti-inflammatory activity of curcumin derivatives, 24 analogues were synthesized and their structures were confirmed by 1H NMR and electron ionization (EI) mass spectrometry. Most...