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Improved sensitivity of HPLC-ESI/MS analysis of the of biodegradation products of alkyl ethoxylates and alkylphenol ethoxylates by post-column lithium addition

Matuszak M., Ostrowski W., Frański R.

Ars Separatoria Acta

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2011

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No. 8

25-37

EN

Biodegradation of nonylphenol ethoxylates and dodecyl ethoxylates (C9H19-C6H4- -(OCH2CH2)n-OH and C12H25-(OCH2CH2)n-OH respectively) in river water in a static die-away test was performed. By using high performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI/MS), surfactants containing 2-4 ethoxylene units were detected as biodegradation products. Post-column addition of a number of metal cation was tested in order to improve the sensitivity of HPLC-ESI/MS analysis. Among the metal cations taken into account, the use of a lithium cation gave the best results provided that the cone voltage was increased to 40-50 V.

2

Biodegradation of alkyl ethoxylates and alkylphenol ethoxylates in river water in a static die-away test as studied by HPLC-ESI/MS

Zembrzuska J., Frańska M., Schroeder G., Frański R.

Ars Separatoria Acta

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2009/2010

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No. 7

69-76

EN

Biodegradation of nonylphenol ethoxylates and dodecyl ethoxylates (C9H19-C6H4- (OCH2CH2)n-OH and C12H25-(OCH2CH2)n-OH, respectively) in river water in a static die-away test was analyzed by using high performance liquid chromatography with mass spectrometric detection using the Applied Biosystems quadrupole-linear ion trap mass spectrometer Model 4000 QTrap. Surfactants containing 2-4 ethoxylene units may be regarded as persistent metabolites of longer surfactants. Homologues C9H19-C6H4- (OCH2CH2)5-OH and C12H25-(OCH2CH2)5-OH underwent substantial biodegradation till the 9th day of the test, their further biodegradation proceeded very slowly. The longer homologues (n > 5) were fully biodegraded during the test. Although the biodegradation of the surfactants studied consisted in shortening the ethoxylene chain (hydrophilic part), it was found that the hydrophobic part also affected their biodegradation.

3

The effect of benzene moiety fused with macrocyclic ring on the proton affinity of crown ethers studied in MS/MS experiment

Frański R., Gierczyk B.

Ars Separatoria Acta

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2008

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No. 6

61-68

EN

In this paper we address the question how the presence of an aromatic moiety affects the proton affinity of crown ethers. In order to compare the proton affinities of crown ethers studied (M), we compared the abundances of protonated crown ethers ([M + H]+ ions) with the abundance of the ion [NH2-B15C5 + H]+ (formally also protonated crown ether). Both [M + H]+ and [NH2-B15C5 + H]+ were formed as a result of decomposition of [NH2-B15C5 + H + M]+. The presence of a benzene moiety fused with a macrocyclic ring strongly decreases the ratio [M + H]+/[NH2-B15C5 + H]+. Thus, the higher ring strain caused by the benzene moiety leads to a substantial lowering of the proton affinity of crown ethers. It is also suggested that for protonated benzocrown ethers the ring strain is partly compensated by the proton-đ interaction. The presence of an NO2 group decreases the electron density on the aromatic ring and, consequently, the proton-đ interaction is suppressed. As expected, the proton affinity of benzo-crown ethers increases with increasing size of their cavity since the ring strain is lower for larger molecules. An unexpectedly high proton affinity of dicyclohexano-18-crown-6 (DC18C6) has been observed.

4

Mass Spectrometric Decompositions of Platinum(II) Complexes with 1,3,4-Thiadiazoles and Dimethyl Sulfoxide. Changes in the Complexation Mode

Frański R., Gierczyk B.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 3

453-462

EN

The platinum(II) complexes with 1,3,4-thiadiazoles and dimethyl sulfoxide have been studied by tandem mass spectrometry. Under the ion trap mass spectrometric condition, after the DMSO molecule(s) loss, changes have been observed in the complexation mode. They consisted in a fast conversion of one complex into another, provided that pyridine nitrogen atom contributes to the platinum cation complexation. The complexes studied have also shown a loss of the pyridine- or benzenenitrile molecule and HCl molecule. The eliminated HCl may contain a hydrogen atom originating from DMSO or from the aryl moiety. In the latter case, further decomposition of the ions formed involves (among others) a complex skeletal rearrangement yielding 2-thiopyridineplatinum cation.

5

Electron Ionization Mass Spectrometric study of 5-Benzylidene Rhodanines Differentially Substituted in the Phenyl Ring and 3-Phrnyl Rhodanine

Frański R., Schroeder G., Shendrik A.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 8

1285-1293

EN

The electron ionization behaviour of 5-benzylidene rhodanines (1-10) and 3-phenyl rhodanine (11) was studied. For each of the 1-10 an efficient loss of mass 87, namely the loss of HNCS and CO molecules, was observed. The compounds containing a hydroxy group at the ortho position to the rhodanine moiety showed also an abundant fragment ion formed by the loss of HNCS. The other phenyl ring substituents did not affect this fragmentation pathway. On the other hand, decomposition of the [M-87]+ _ fragment ion strongly depends on the phenyl ring substitution, e.g. for 5 having a methoxy group at the meta position to the rhodanine moiety, in contrast to its ortho and para correspondents 4 and 6, the loss of the fragments HCO. and H2CO proceeded. 3-Phenyl rhodanine lost the ketene molecule yielding the fragment ion of m/z 167. On the grounds of its decomposition and comparison with reference compound decomposition it was deduced that this ion had the structure of 2-mercaptobenzothiazole.

6

Fragmentation and Skeletal Rearrangements of the Protonated Spiro(2H-benzimidazole-2-4'-pyrazole)-5'-one Dyes Studied by Electrospray Ionization and Liqiud Secondary Iohn Mass Spectrometry

Frański R., Kozik T., Schroeder G., Kucybała Z., Pączkowski J.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 10

1301-1312

EN

The mass spectrometric decomposition of the titled compounds was studied by using electrospray ionization (ESI) and liquid secondary ion mass spectrometry (LSIMS) as a methods for [M+H]+ ions generation. Low-energy collision induced dissociation (fragmentation "in source") mass spectra for ESI and B/E linked scan mass spectra of metastable ions for LSIMS were performed. In order to better understand the decomposition of the compounds studied, the mass spectra of isotopically labelled compounds were recorded. The fragmentation pathways of [M+H]+ ions were found to be complex and skeletal rearrangements were observed. It was deduced that subsequent loss of NH3 and H2O molecules leads to the formation of ions with polycyclic structures. The fragment ion [133]+ and its complementary fragment ion [M+H-132]+ can be considered as protonated molecules of 3-methyl-1H-indazole and 2-hydroxyquinoxaline, respectively. Loss of the CH3CN molecule also occurs and this is rather simply process. Aniline elimination (H2N-C6H5) and formation of ions at m/z 146 are complex processes and it was difficult

7

The Theoretical calculated Stability of Benzoyl Ions and Their Relative Intensities in the Electron Ionization Mass Spectra of Some 2,5-Disubstituted-1,3,4-oxadiazoles

Eitner K., Frański R., Schroeder G., Rybachenko V., Szwajka O. P.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 5

761-764

8

Mass Spectrometric Investigation of Tautomers of N-Substituted 4-Iminopentan-2-ones in the Gas Phase

Urbaniak W., Frański R., Gierczyk B.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 3

429-441

EN

Mass fragmentation of 4-iminopentan-2-one N-substituted with organosilicon group suggests that in the gas phase upon electron ionization (EI) conditions only 4-imino- 2-keto tautomer occurs. The simultaneous occurrence of 4-aminopent-3-en-2-keto tautomeric form was ruled out on the basis of mass fragmentation of some alkylaromatic derivatives of 4-aminopent-3-en-2-one.

9

Mass Spectrometric Behavior of Acyclic polydentate Ligands: 4-(Arylimino)pentan-2-ones

Płaziak A., Urbaniak W., Frański R., Gierczyk B.

Polish Journal of Chemistry

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1999

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Vol. 73, nr 8

1301-1313

EN

Electron ionization (El) mass spectra of some aromatic derivatives of 4-iminopentan-2-one are discussed. Their mass fragmentation suggests the occurrence in the gas phase of 4-imino-2-keto tautomer only.

10

Mass spectrometry of some derivatives of 5-(indol-2-yl)pyrimidine

Celewicz L., Frański R., Urjasz H., Płaziak A.S.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 4

725-734

EN

The electron impact (EI) and liquid secondary ion (LSI) mass spectra of 5-(indol-2--yl)pyrimidine derivatives are discussed. It was established that 5-(indol-2--yl)uracils, instead of the cleavage of the single carbon-carbon bond between uracil and indole ring, form stable ions with additional linkage between 4O-oxygen of uracil and CH2 group at the 3 position of indole moiety. Similarly, 5-(indol-2-yl)cytosines yield stable tetracyclic ions with new linkage between 4N-nitrogen of cytosine and CH2 group at the 3 position of indole ring.

11

Mass spectrometric behaviour of alkali and alkaline earths acetylacetonates

Płaziak A.S., Urbaniak W., Frański R., Gierczyk B.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 3

504-510

EN

EI spectra of acetylacetone, alkali acetylacetonates and acetylacetonates of alkaline earths of formulae M(I)(acac) and M(II)(acac)2 (where M(I)=LI, Na, K, Rb, Cs, M(II)=Be, Mg, Ca, Sr, acac= acetylacetonate ligand) were ibtained using mass spectrometry. Ligand-ions were observed in each spectrum. Metal cations were present only for the elements of group I. The detection of polymetric species of general formula [M(x)(acac)(y)](+) supports the conclusion, that polymeric species of acetylacetonates of group I and II are commonly present in the gas phase.