Detection techniques in speciation analysis of organotin compounds by liquid chromatography

Development and Application of a Novel QuEChERS Method for Monitoring of Tributyltin and Triphenyltin in Bottom Sediments of the Odra River Estuary, North Westernmost Part of Poland

A Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction method combined with Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) for determination of organotin compounds (OTC) has been newly developed. The novel analytical method was validated and the quality of the results was tested by the use of certificate reference material of freshwater sediment BCR 646. The method was applied in determination of OTC concentration in real samples of bottom sediments collected from the Polish part of Odra River Estuary. The samples came from locations with different anthropogenic impact. Additionally, the extraction recovery of OTC and matrix effect on MS signal response was investigated based on those real environmental samples. It was found that organic compounds and anthropogenic contaminations present in bottom sediments may affect extraction efficiency of the organotin compounds (OTC) and change the matrix effect on MS signal response. The highest concentrations of tributyltin were found in bottom sediments collected from locations in vicinity of the Szczecin harbor and shipyards. The presence of triphenyltin above limit of detection (5 ng TPhT/g of sediment) was observed only in two samples and its concentration was several times lower compared to concentration of tributyltin (from 58 ng/g to 5263 ng/g). In spite of the fact that, the application of TBT-based paints on hull of vessel entering EU ports has been banned by European Commission regulation No. 782/2003 since 2008, the OTC compounds are still present in bottom sediment and pose significant threat to the environment. This threat should be taken into account during dredging of waterways and other hydrotechnical works.

Marine environment pollution: The contribution of mass spectrometry to the study of seawater

The study of marine pollution has been traditionally addressed to persistent chemicals, generally known as priority pollutants; a current trend in environmental analysis is a shift toward "emerging pollutants," defined as newly identified or previously unrecognized contaminants. The present review is focused on the peculiar contribution of mass spectrometry (MS) to the study of pollutants in the seawater compartment. The work is organized in five paragraphs where the most relevant groups of pollutants, both "classical" and "emerging," are presented and discussed, highlighting the relative data obtained by the means of different MS techniques. The hyphenation of MS and separative techniques, together with the development of different ion sources, makes MS and tandem MS the analytical tool of choice for the determination of trace organic contaminants in seawater. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 37:492-512, 2018.

Acid–base and coordination properties of 2-phenyl-3-hydroxy-4-quinolones in aqueous media

2-Phenyl-3-hydroxy-4-quinolones bind metal ions with selective fluorescence response in aqueous media.

Storage stability studies for tributyltin determination in human urine samples using headspace solid-phase microextraction and gas chromatography mass spectrometry

A headspace solid-phase micro-extraction (HS-SPME) method was employed in order to study the effect of storage conditions of human urine samples spiked with tributyltin (TBT) using gas chromatography and mass spectrometry. To render the analyte more volatile, the derivatization (ethylation) was made in situ by sodium tetraethylborate (NaBEt(4) ), which was added directly to dilute unpreserved urine samples and in buffers of similar acidity. The stability of TBT in human urine matrix was compared with the stability of TBT in buffer solutions of similar pH value. Critical parameters of storage conditions such as temperature and time, which affect the stability of TBT in this kind of matrix, were examined extensively. The tests showed that the stability of TBT remains practically satisfactory for a maximum of 2 days of storage either at +4 or 20°C. Greater variations were observed in the concentration of TBT in human urine samples at +4°C and lower ones at -20°C over a month's storage. The freeze-thaw cycles have negative effect on the stability and should be kept to a minimum. The results from spiked urine samples are also discussed in comparison to those acquired from buffer solutions of equal TBT concentration.

Structural analysis of organometallic compounds with soft ionization mass spectrometry

The analysis of organometallic compounds with mass spectrometry has some special features in comparison with organic and bioorganic compounds. The first step is the choice of a suitable ionization technique, where the electrospray ionization is certainly the best possibility for most classes of organometallic compounds and metal complexes. Some ionization mechanisms of organometallic compounds are comparable to organic molecules, such as protonation/deprotonation, and adduct formation with sodium or potassium ions; however, in many cases, different mechanisms and their combinations complicate the spectra interpretation. Organometallics frequently undergo various types of adduct and polymerization reactions that result in significantly higher masses observed in the spectra in comparison to molecular weights of studied compounds. Metal elements typically have more natural isotopes than common organic elements, which cause characteristic wide distributions of isotopic peaks; for example, tin has ten natural isotopes. The isotopic pattern can be used for the identification of the type and number of metal elements in particular ions. The ionization and fragmentation behavior also depend on the type of metal atom; therefore, our discussion of mass spectra interpretation is divided according to the different type of organometallic compounds. Among various types of mass spectrometers available on the market, trap-based analyzers (linear or spherical ion-traps, Orbitrap) are suitable to study complex fragmentation pathways of organometallic ions and their adducts, whereas high-resolution and high-mass accuracy analyzers (time-of-flight-based analyzers, or Fourier transform-based analyzers-Orbitrap or ion cyclotron resonance mass spectrometers) provide accurate masses applicable for the determination of the elemental composition of individual ions.

On-line solid-phase extraction coupled with liquid chromatography/electrospray ionization mass spectrometry for the determination of trace tributyltin and triphenyltin in water samples

On-line solid-phase extraction (SPE) for pre-concentration and sample cleanup is one strategy to reduce matrix effects and to simultaneously improve detection sensitivity in liquid chromatography/mass spectrometry (LC/MS). This paper describes an on-line SPE-LC/MS method for the determination of tributyltin (TBT) and triphenyltin (TPhT) at trace levels in water samples. The direct coupling of an on-line C18 pre-column to LC/MS was used to pre-concentrate TBT and TPhT at trace levels from waters and to remove interfering matrix effects. Pre-concentration was followed by separation of TBT and TPhT on a C18 column using a mobile phase containing 0.1% (v/v) HCOOH/5 mM HCOONH4 and methanol. While both electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) can be interfaced with MS for the detection of TBT and TPhT, ESI-MS was preferred for this application. The calibration curve for the targets was linear in the concentration range 0.1-30 microg L(-1). The detection limit (signal-to-noise (S/N) ratio = 3) was 0.02 microg L(-1) when 3.0 mL of sample was enriched on the C18 pre-column. The recoveries of TBT and TPhT in spiked waters were from 81.0 to 101.9%. The reproducibilities for the analysis of the standard mixture (10 microg L(-1)) for TBT and TPhT were 13.1 and 5.0%, respectively. The developed method was an easy and fast way to analyze TBT and TPhT in water samples.

Organic mass spectrometry and control of fragmentation using a fast flow glow discharge ion source

Representative organic vapors have been introduced into the flowing afterglow of a low power (<5 W) dc-glow discharge, coupled to a quadrupole mass spectrometer. When a positive bias was applied to the ion sampling orifice, the very surprising result was that molecular mass spectra were obtained with a high sensitivity. When a negative bias was applied to the ion sampling orifice, fragmentation of the analyte was observed with an increase in the extent of ion dissociation as the voltage was increased. The breakdown pattern is compound-specific and would be useful in confirming the identity of an unknown sample. When combined with chromatographic separation, the FFGD-MS technique could be used for chemical speciation studies at the sub-picogram level.

Speciation of organotin compounds by capillary electrophoresis: comparison of aqueous and mixed organic-aqueous systems

A capillary electrophoresis method with direct ultraviolet detection was developed for the analysis of organotin species. Despite the fact that direct detection of organotin compounds by ultraviolet absorption is difficult because most organotins possess poor chromophoric properties, the application of low wavelength (lambda = 200 nm) and mixed organic-aqueous media enabled a significant enhancement in sensitivity. A mixed organic-aqueous system (10% methanol/40% acetonitrile/50% H2O) containing acetic acid and tetrabutylammonium perchlorate formed the basis for rapid, efficient and sensitive determinations of organotin cations such as tripropyltin, tributyltin, triphenyltin and diphenyltin. The concentration limits of detection (LOD) for the four organotin compounds were in the range of 0.4-14 microM, comparable to that obtained with the most sensitive indirect UV method reported until now, and took advantage of a stable baseline, a symmetric peak shape and an absence of disturbing system peaks. The relative standard deviations (n = 7) for the relative peak time and peak area were 0.44-0.77 and 4.8-5.8%, respectively. In addition to sensitivity enhancements, the use of organic-aqueous systems instead of pure aqueous media resulted in improved selectivity and efficiency of separations.