19,912 research outputs found
The significance of platinum in the environment
Tato bakalářská práce, se zabývá sledováním jednotlivých sloučenin platiny ve složkách životního prostředí (voda, půda, ovzduší) a metodami jejich stanovení. V práci je také zmíněno neméně podstatné stanovení platiny v tkáních a tělních tekutinách, v případech kdy je platina využívána ve formě např. cisplatiny jako cytostatikum. Stanovuje se pak samotné cytostatikum, popřípadě jeho deriváty a metabolity na bázi platinových komplexů v klinickém vzorku (moč, plasma). Z metod využívaných pro stanovení Pt vyzdvihuje práce hlavně ICP-AES, ICP-MS, ETA AAS, HPLC. Užitečné se zdají být i on-line propojení těchto metod např. ICP-MS s HPLC nebo ICP AES s HPLC. Pro stanovení platiny je možné využít i spektrofotometrické metody za použití organických i anorganických činidel. Tyto metody jsou zde zmíněny spíše okrajově pro kompletnost, z hlediska praktického využití jsou obtížně reprodukovatelné a málo citlivé. Stanovení také znesnadňuje hydrolýza platinových kovů za vzniku nerozpustných hydratovaných oxidů.This bachelor thesis deals with monitoring of individual platinum compounds in the environment (water, soil, air) and is also reviewing methods used for their analysis. The no less important determination of platinum in tissues and body fluids, when the platinum is used in form of a cisplatin as an anticancer drug, is also mentioned. Afterwards the anticancer drug itself or its derivatives and metabolites on the base of platinum complexes in clinical sample (urine, plasma) are determined. Mainly the ICP-AES, ICP-MS, ETA-AAS, HPLC methods are highlighted from the methods used for the determination of Pt. The on-line connection between some of these methods such as ICP-MS with HPLC or ICP-AES with HPLC seems to be useful. The spectrofotometric methods using organic and inorganic agents can also be used for the determination of platinum. These methods are mentioned here rather marginally, just for completeness. In terms of practical use they are difficultly reproducible and not very sensitive. The hydrolysis of platinum metals to form insoluble hydrated oxides makes also the determination difficult.
DEVELOPMENT OF IMPROVED METHODS FOR THE ANALYSIS OF METALLOPORPHYRINS IN COALS, SEDIMENTS AND OILS
A high temperature gas chromatography (HTGC)-inductively
coupled plasma-mass spectrometry (ICP-MS) interface was
successfully developed which allowed the analysis of
metalloporphyrins (Retention Index >6000), with detection
limits of less than 1 nanogram on column. The system was used
together with conventional HTGC-flame ionization detection and
HTGC-mass spectrometry (MS) for the analysis of geoporphyrin
fractions from Julia Creek, Serpiano, Marl Slate and Green
River shales. This allowed the rapid fingerprinting of the
metals chelated to the porphyrins in these samples. Previously
unreported titanium porphyrins were detected in two of these
shales, the Marl Slate and Julia Creek. An iron porphyrin
fraction from Bagworth coal was also examined for the first
time using both HTGC-ICP-MS and HTGC-MS and the distributions
of the ETIO porphyrins calculated.
The HTGC method was found to be useful only for qualitative
scanning of the geoporphyrin fractions. This was due to
problems with the stability of the gas chromatographic columns
used for these analyses. The columns used were found to last
between 5 and 10 injections, after which the porphyrins
appeared as broad humps, slowly eluting off the column.
A high performance liquid chromatography (HPLC)-ICP-MS method
was developed to allow the quantitative analysis of
geoporphyrins, which was not possible with the HTGC-ICP-MS
method. The HPLC-ICP-MS interface used allowed good
chromatographic separation to be achieved, with less than 10 %
loss in column efficiency. This system was used for the
quantitative analysis of gallium and nickel porphyrins from
coals and shales respectively. The qualitative distributions
obtained for the geoporphyrins using HPLC-ICP-MS
showed good agreement with the HPLC-UV/VIS results.
A GC-Low Pressure-ICP-MS interface was designed and constructed
and the analysis of metalloporphyrins attempted. The
metalloporphyrins were not successfully eluted through the GCLP-
ICP-MS system. However, a number of more volatile
organometallic compounds were analysed (tetraethyl lead,
ferrocene and tetrabutyltin). Interestingly the system also
produced fragment molecular ions of chlorobenzene, bromobenzene
and iodobenzene at low plasma powers (-10 W), using the carrier
gas as the plasma gas (helium). Thus the system could be used
to obtain both atomic and molecular spectra, which has not been
achieved previously
ANALYSIS OF PHARMACEUTICALS AND BIOMOLECULES USING HPLC COUPLED TO ICP-MS AND ESI-MS
The work described within this thesis explores the use of HPLC coupled with ICPMS
and ESI-MS in order to develop novel methods which overcome specific
analytical challenges in the pharmaceutical industry.
A membrane desolvation interface has been evaluated for coupling high
performance liquid chromatography (HPLC) with inductively coupled plasma mass
spectrometry (ICP-MS). Desolvation of the sample prior to reaching the plasma
was shown to facilitate a versatile coupling of the two instrumental techniques,
enabling chromatographic eluents containing up to 100 % organic to be used. This
interface also allowed gradient elution to be used with ICP-MS.
Tris(2,4,6-trimethoxyphenyl)phosphonium propylamine bromide (TMPP) was used
for the derivatisation of maleic, fumaric, sorbic and salicylic acids to facilitate
determination by HPLC-electrospray ionisation tandem mass spectrometry (ESIMS/
MS) in positive ion mode. Improvements in detection limits post-derivatisation
were achieved, and this method was successfully used for the determination of
sorbic acid in a sample of Panadol™.
HPLC coupled with sector field inductively coupled plasma mass spectrometry
(SF-ICP-MS) has been used for the determination of maleic, sorbic and fumaric
acids after derivatisation with TMPP. This allowed 31P+ selective detection to be
performed for these compounds, which are normally undetectable by ICP-MS.
Optimal reagent conditions for the derivatisation of 0.1 mM maleic acid were: 1
mM TMPP; 10 mM 2-chloro-1-methylpyridinium iodide (CMPI); 11 mM
triethylamine. The efficiency of the derivatisation reaction was estimated to be
between 10-20%. Detection limits, estimated as 3 times baseline noise, were
0.046 nmol for TMPP and 0.25 nmol for derivatised maleic acid, for a 5 f.JL
injection.
Following on from this, a novel derivatising reagent, tris(3,5-dibromo-2,4,6-
trimethoxyphenyl) phosphonium propylamine bromide (BrTMPP), was synthesised
and subsequently characterised by proton NMR spectroscopy and ESI-MS. This
was utilised to derivatise maleic acid, with a 9-fold increase in sensitivity gained
when analysed by bromine selective detection as apposed to phosphorus
selective ICP-MS. This derivatising reagent (BrTMPP) was also utilised to
determine the degree of phosphorylation on phosphorylated peptides. A
phosphorus containing carboxylic acid was successfully derivatised and the
correct Br:P ratio was determined for this compound by ICP-MS. However,
phosphorylated peptides were not successfully derivatised by BrTMPP. A
combination of UV and phosphorus selective ICP-MS was also used to distinguish
between phosphorylated and un-phosphorylated peptides after HPLC separation.GlaxoSmithKiin
Development of post-column hydride generation for analysis of glutathione complexes of arsenic by HPLC-(HG)-ICP-MS
Diplomová práce se zabývá metodou kapalinové chromatografie s postkolonovým generováním hydridů ve spojení s hmotnostní detekcí s indukčně vázaným plazmatem (HPLC-HG-ICP-MS) pro analýzu glutathionových komplexů arsenu v biologických vzorcích. Cílem bylo ověřit vhodnost metody a provést pilotní studie na enzymatické methylační směsi arsenu s glutathionem a v moči. Zařazení kroku postkolonového generování hydridů řeší problém změny citlivosti ICP-MS při použití gradientové eluce. Pomocí standardů glutathionových komplexů bylo ověřeno, že metoda HPLC-HG-ICP-MS umožňuje kvalitativní i kvantitativní analýzu těchto komplexů. Mez detekce byla stanovena na 5 pg/ml. Analýzou methylační směsi arsenu s glutathionem bylo zjištěno, že ve směsi se v průběhu methylace vyskytuje pouze komplex dimethylarsen glutathion (DMAs(GS)) a bylo ověřeno, že přítomnost enzymu je pro vznik komplexu nezbytná. Ve vzorcích moči neexponovaných lidí analyzovaných metodami HPLC-HG-ICP- MS a generováním hydridů s vymrazováním ve spojení s hmotnostní detekcí s indukčně vázaným plazmatem (HG-CT-ICP-MS) byla zjištěna pouze přítomnost volných pětimocných arsenových specií, glutathionové komplexy ani trojmocné specie pozorovány nebyly.This thesis develops high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-HG-ICP-MS) method used for the analysis of glutathione arsenic complexes in biological samples. The aim of the thesis was to verify the suitability of this methods and to perform pilot studies on analysis of the enzymatic methylation assay containing glutathione and urine. Inclusion of post-column hydride generation step resolves the problem of changing sensitivity of ICP-MS with gradient elution. Using the standards of glutathione complexes, it was verified that the HPLC-HG-ICP-MS method can provide both qualitative and quantitative analysis of these complexes. The limit of detection was found at 5 pg/ml. Analysis of the methylation assay of arsenic with glutathione showed that only DMAsGS complex occurs in the assay during methylation. It was verified that the presence of the enzyme is required for the complex formation. In the samples of urine from unexposed people analyzed by HPLC- HG-ICP-MS and hydride generation-cryotrapping-inductively coupled plasma mass spectrometry (HG-CT-ICP-MS), only the presence of free pentavalent arsenic species was found, whereas neither glutathione complexes nor trivalent species could be observed.Department of Analytical ChemistryKatedra analytické chemieFaculty of SciencePřírodovědecká fakult
Nano-particle labelling of nucleic acids for enhanced detection by inductively-coupled plasma mass spectrometry (ICP-MS)
Oligonucleotides containing biotin functionality were successfully labelled with a streptavidin nanogold conjugate and subsequently separated and analysed by High Performance Liquid Chromatography–Inductively Coupled Plasma–Mass Spectrometry (HPLC-ICP-MS)
A field deployable method for a rapid screening analysis of inorganic arsenic in seaweed
The authors thank the support for getting the seaweed samples from the projects funded under the Department of Agriculture, Food and the Marine’s Competitive research programmes in Ireland. Reference number 14 SF 860. The authors thank Corny Brombach for the graphical abstract.Peer reviewedPublisher PD
Accuracy of a method based on atomic absorption spectrometry to determine inorganic arsenic in food : Outcome of the collaborative trial IMEP-41
Peer reviewedPublisher PD
Accurate quantification of selenoproteins in human plasma/serum by isotope dilution ICP-MS : focus on selenoprotein P
Acknowledgements The research leading to these results was funded by the EMRP Joint Research Project “Metrology for metalloproteins” (HLT-05 2012). The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.Peer reviewedPostprin
Atomic spectrometry update. Clinical and biological materials, foods and beverages
This review discusses developments in elemental mass spectrometry, atomic absorption, emission and fluorescence, XRF and LIBS, as applied to the analysis of specimens of clinical interest, foods and beverages. Sample preparation procedures and quality assurance are also included.</p
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