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Identification and quantification of allelochemicals associated with weed suppression in sweetpotatoVarsha, Varsha 12 May 2023 (has links) (PDF)
Mississippi ranks among the leading states in sweetpotato production in the US. However, managing weeds in sweetpotato fields presents a significant challenge, and the limited availability of herbicides labeled for use in sweetpotato makes it even more challenging. The widespread and repeated use of herbicides has led to the development of weed resistance. In addition, herbicides are incompatible with the organic production system. Finding sustainable weed management strategies to provide weed control options for organic cultivation and detain the development of herbicide-resistant weeds under conventional crop production is imperative. The natural chemicals released by the plants, also called allelochemicals, can potentially suppress weeds and be used for weed management under conventional and organic cultivation systems. The current study aimed to 1) screen the sweetpotato varieties for their weed-suppressing effect on the growth of weeds in controlled conditions using a stair-step structure, 2) evaluate the allelopathic suppression of selected sweetpotato varieties under field conditions, and 3) identify and quantify allelochemicals released by the roots of seventeen sweetpotato varieties. Results of the current study on the availability of allelopathic sweetpotato varieties will benefit organic producers by enhancing crop productivity. They will decrease reliance on synthetic herbicides in conventional farming systems. Identifying and quantifying allelochemicals will also improve our knowledge of allelopathy and provide valuable information for developing allelopathic sweetpotato varieties.
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MOLECULAR DRIVERS OF SPECIFICITY IN HUMAN RIBONUCLEOTIDE REDUCTASEKnappenberger, Andrew John 02 June 2017 (has links)
No description available.
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Use of Surfactant Modifiers for High-Performance Liquid Chromatography of Aliphatic and Aromatic Acids and Capillary Electrophoresis of GlycosaminoglycansFasciano, Jennifer Marie 23 November 2015 (has links)
No description available.
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Quantification of 3-methoxy-4-hydroxyphenylglycol in human saliva by an optimised HPLC method with electrochemical detectionViljoen, Francois Petrus January 2011 (has links)
Thesis (M. Tech.) - Central University of Technology, Free State, 2011
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Ultra high performance liquid chromatography tandem mass spectrometry for rapid analysis of trace organic contaminants in waterAnumol, Tarun, Merel, Sylvain, Clarke, Bradley, Snyder, Shane January 2013 (has links)
BACKGROUND:The widespread utilization of organic compounds in modern society and their dispersion through wastewater have resulted in extensive contamination of source and drinking waters. The vast majority of these compounds are not regulated in wastewater outfalls or in drinking water while trace amounts of certain compounds can impact aquatic wildlife. Hence it is prudent to monitor these contaminants in water sources until sufficient toxicological data relevant to humans becomes available. A method was developed for the analysis of 36 trace organic contaminants (TOrCs) including pharmaceuticals, pesticides, steroid hormones (androgens, progestins, and glucocorticoids), personal care products and polyfluorinated compounds (PFCs) using a single solid phase extraction (SPE) technique with ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method was applied to a variety of water matrices to demonstrate method performance and reliability.RESULTS:UHPLC-MS/MS in both positive and negative electrospray ionization (ESI) modes was employed to achieve optimum sensitivity while reducing sample analysis time (<20min) compared with previously published methods. The detection limits for most compounds was lower than 1.0 picogram on the column while reporting limits in water ranged from 0.1 to 15ng/L based on the extraction of a 1L sample and concentration to 1mL. Recoveries in ultrapure water for most compounds were between 90-110%, while recoveries in surface water and wastewater were in the range of 39-121% and 38-141% respectively. The analytical method was successfully applied to analyze samples across several different water matrices including wastewater, groundwater, surface water and drinking water at different stages of the treatment. Among several compounds detected in wastewater, sucralose and TCPP showed the highest concentrations.CONCLUSION:The proposed method is sensitive, rapid and robust / hence it can be used to analyze a large variety of trace organic compounds in different water matrixes.
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Novel methods of chemical speciation of Pt(IV/II) complexes in acid halide-rich solutions by ion-pair RP-HPLC coupled to ICP-OES/MS in conjunction with 195Pt NMRVan Wyk, Pieter-Hugo 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: In this work a robust reversed phase ion-pairing high performance liquid chromatographic
(RP-HPLC) method has been developed for the separation, characterization and quantification of
all possible [PtCl6-nBrn]2- (n = 0 – 6) and [PtCl4-nBrn]2- (n = 0 – 4) complex anions using UV-Vis
detection. High resolution 195Pt NMR of more concentrated PtII/IV solutions served to validate the
relevant species assignments, particularly those of the stereoisomer species, cis- and trans-
[PtCl4Br2]2-, [PtCl2Br4]2- and mer- and fac-[PtCl3Br3]2-. Quantification of the PtII/IV species was
achieved by means of IP-RP-HPLC coupled to either ICP-MS or ICP-OES, and together with the
UV-Vis absorption spectra obtained by photodiode array (PDA) recording of all eluted species,
allowed for the determination of the photometric characteristics (λmax and ε) of all the PtII/IV
species. This data enables practical speciation studies of such PtII/IV complex anions using
standard analytical equipment.
The hyphenation of ion-pairing RP-HPLC to ICP-OES allows for the successful determination
of the Pt to halide mole ratios of individually separated species in order to characterize these
species in a novel manner. The Pt to chloride and/or Pt to bromide mole ratio of the [PtCl4]2- and
the series of [PtCl6-nBrn]2- (n = 0 – 6) complexes were determined using HPLC-ICP-OES based
on the 177.708 nm Pt, 134.724 nm Cl and 148.845 nm Br emission lines and served as a
technique for the unambiguous chemical speciation of such complexes.
An increase in sensitivity of the developed method was achieved by the use of an ion-pairing
reversed phase ultra high performance liquid chromatography electrospray ionization quadrupole
time-of-flight mass spectrometry (UHPLC-ESI-Q-TOF-MS) method. This method proved
capable of separating and characterizing the homoleptic and heteroleptic [PtIVCl6-nBrn]2-
(n = 0 – 6) and mono-aquated [PtIVCl5-nBrn(H2O)]- (n = 0 – 5) complex anions in well defined
acidic aqueous solutions. Ion-pairing ultra high performance liquid chromatography separation based on the volatile ion-pairing reagent, tributylamine, provided adequate chromatographic
resolution as well as sufficiently low background noise for high resolution ESI-Q-TOF-MS
detection. The wealth of structural information contained in the mass spectra obtained for each
PtIV species simplified the identification of individual species. Moreover, the general
fragmentation trends encompassing a constant incremental change of 44 Da (79/81Br - 35/37Cl)
resulting from the successive substitution of Cl- by Br-, in combination with the observed elution
order, facilitated the relevant species assignments. The developed method enabled the relative
rapid (<13 min) characterization of all 22 [PtCl6-nBrn]2- (n = 0 – 6) and mono-aquated
[PtCl5-nBrn(H2O)]- (n = 0 – 5) species.
Quantification of each individual [PtCl6-nBrn]2- (n = 0 – 6) species by means of ion-paring
HPLC-UV-Vis allowed for the determination of all 17 stability constants for the PtIV chloridobromido
halide exchange reaction network. Determination of the associated Gibbs free energies
for each ligand exchange reaction step, o
rxnK ΔG
n
(n = 1 - 17), together with energy conservation
relationships, served to validate the accuracy of the experimentally calculated stability constants.
The experimentally determined overall formation constant, or ΔGo
rxn, and those calculated using
the standard reaction half cell reduction potentials of [PtCl6]2- and [PtBr6]2- were in good
agreement, further confirming the experimentally obtained thermodynamic parameters. The
thermodynamic driving force for the PtIV chloride-bromido exchange reactions is attributed to
the hydration of the halide ligands, which drives the reaction towards the bromido PtIV species in
aqueous solutions, even though the chlorido PtIV complexes are energetically favoured in this
reaction network. Evaluation of other metal cation halido exchange reactions shows that all metal
halido complexes exhibit the F- >> Cl- > Br- > I- order of thermodynamic stability and is only
inverted due to the solvation of the relevant halide ligands. Furthermore, density functional
theory (DFT) was used to predict the thermodynamic stabilities with respect to the isodesmic
reactions involving chlorido-bromido PtIV stereoisomer pairs and chlorido-bromido PtIV ligand
exchange reactions of the [PtCl6-nBrn]2- (n = 0 – 6) species and confirm the F- >> Cl- > Br- > I-
order of thermodynamic stability as well as determining the ΔΔGo
rxn within the range of 8 - 20
kJ.mol-1 to the experimentally determined ΔΔGo
rxn. / AFRIKAANSE OPSOMMING: Tydens hierdie studie is „n robuuste “reverse-phase” ioonparing hoë-verrigting vloeistof
chromatografie, RP-IP-HPLC, metode ontwikkel vir die skeiding, karakterisering en
kwantifisering van alle moontlike [PtCl6-nBrn]2- (n = 0 – 6) en [PtCl4-nBrn]2- (n = 0 – 4) kompleks
anione waar UV-Vis as detektor gebruik word. Die relavante spesies toedelings wat gemaak is,
veral ten opsigte van die cis- en trans-[PtCl4Br2]2-, [PtCl2Br4]2- en mer- en fac-[PtCl3Br3]2-
stereo-isomeerpare, is deur middel van hoë-resolusie 195Pt KMR van meer gekonsentreerde PtII/IV
oplossings bevestig. Die PtII/IV spesies was gekwantifiseer deur die IP-RP-HPLC aan of „n ICPMS
of „n ICP-OES te koppel. Daarenbowe was dit moontlik om die fotometriese eienskappe
(λmax en ε) van elke individuele PtII/IV komplex anion te bepaal deur die UV-Vis absorpsie
spektrum van elke elueerende spesies met PDA op te neem. Die nuwe metode wat tydens hierdie
studie ontwikkel is het dit dus moontlik gemaak om sulke PtII/IV komplek sanione met standaard
analitiese toerusting prakties te skei.
Verder is gevind dat deur IP-RP-HPLC aan ICP-OES te koppel dit moontlik is om die Pt tot
halied mol verhoudings van elke individueel geskeide spesies te bepaal en dus hierdie spesies op
„n oorspronklike, nuwe manier te karakteriseer. Die Pt tot chloried en/of Pt tot bromied mol
verhoudings van die [PtCl4]2- en die reeks van [PtCl6-nBrn]2- (n = 0 – 6) kompleks anione, soos
bepaal deur gebruik te maak van HPLC-ICP-OES, is gebasseer op die 177.708 nm Pt, 134.724
nm Cl en 148.845 nm Br emissie lyne. Hierdie metode kan gebruik word vir die eenduidige
chemiese skeiding van hierdie komplekse.
Die sensitiwiteit van hierdie metode was egter verder verbeter deur gebruik te maak van
ioonparing “reverse-phase” ultra hoë-verrigting vloeistof chromatografie gekoppel met
elektrosprei ionisasie quadropool “time-of-flight” massa spektrometrie (UHPLC-ESI-Q-TOFMS).
Deur dit te doen is dit nou selfs moontlik om die homoleptiese en heteroleptiese [PtIVCl6-nBrn]2- (n = 0 – 6) spesies, asook die “mono-aqauted” [PtIVCl5-nBrnH2O]- (n = 0 – 5)
spesies in „n goed gedefinieërde aangesuurde waterige oplossings te skei en te karakteriseer. Die
vlugtige ioon-paringsreagent, tributielamien, is vir die skeidingsproses op die IP-UHPLC gebruik
om te verseker dat voldoende chromatografiese resolusie, so wel as lae genoeg agtergrondgeraas,
verkry word vir hoë-resolusie ESI-Q-TOF-MS deteksie. Die rykdom informasie vervat in die
massaspektrum van elke PtIV spesies het die indentifikasie van elke spesies vergemaklik.
Daarenbowe het die fragmentasie tendens, aanduidend van „n konstante inkrementele
verandering van 44 amu (71/81Br – 35/37Cl) weens die opeenvolgende substitusie van Cl- met
Br-, tesame met die elusie volgorde, die spesies-toedelings gefasiliteer. Met hierdie nuut
ontwikkelde metode is dit nou moontlik om al 22 [PtCl6-nBrn]2- (n = 0 – 6) en “mono-aquated”
[PtCl5-nBrnH2O]- (n = 0 – 5) spesies in „n relatiewe kort tydperk (< 13 min) te karakteriseer.
Deurdat elke [PtCl6-nBrn]2- (n = 0 – 6) spesies nou individueel met IP-HPLC-UV-Vis
gekwantifiseer kan word, is dit moontlik om al 17 stabiliteitskonstantes vir die PtIV chloridobromido
halied uitruilingsreaksienetwerk te bepaal. Die geassosieerde Gibbs vrye energie,
ΔG°rxnKn (n = 0 – 17), wat vir elke stap in die uitruilingsreaksienetwerk bepaal is, tesame met die
energiebewaring verhoudings, was gebruik om die akkuraatheid van die eksperimenteel bepaalde
stabiliteitskonstantes te bekragtig. Verdermeer was die waarde van die algehele formasie
konstante wat eksperimenteel bepaal is, ΔG°rxn, in goeie ooreenstemming met dit wat bereken is
deur die standaard reaksie halfsel reduksie potensiale van [PtCl6]2- en [PtBr6]2-. Dus is die
eksperimenteel verkrygde termodinamiese parameters bevestig. Die termodinamiese dryfkrag vir
die PtIV chloried-bromied uitruilingsreaksies is toegereken aan die hidrasie van die halied
ligande, wat in waterige oplossings die reaksie na die bromied PtIV spesies dryf, al is die chloried
PtIV spesies energeties bevoordeel in hierdie reaksienetwerk. Evaluering van ander metaalkatioon-
halied-uitruilreaksies wys dat alle metaal-halied komplekse die F- >> Cl- > Br- > I- orde
van termodinamiese stabiliteit volg en dat hierdie volgorde slegs omgekeer sal word weens
solvasie van hierdie halied ligande. Darenbowe digtheids funksionele teorie (DFT) gebruik om
die termodinamiese stabiliteit met betrekking tot isodesmiese reaksies wat chloried-bromied PtIV
stereoisomeer pare behels te voorspel, sowel as van chloried-bromied PtIV
liganduitruilingsreaksies van die [PtCl6-nBrn]2- (n = 0 – 6) spesies, en bevestig die F- >> Cl- > Br-
> I- volgorde van termodinamiese stabiliteit. Verder was dit ook moontlik om met DFT die
ΔΔG°rxn tot so naby as 8 – 20 kJ.mol-1 te bereken.
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Novel multidimensional fractionation techniques for the compositional analysis of impact polypropylene copolymersCheruthazhekatt, Sadiqali 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Impact Polypropylene Copolymers (IPCs) are extremely complex materials, consisting of a mixture of
polypropylene homopolymer and copolymers having different comonomer (ethylene) contents and
chemical composition distributions. IPC can only be effectively analysed by multidimensional
analytical approaches. For this, initially, the individual components have to be separated according to
any of their molecular characteristics, either by chemical composition distribution (CCD) or molar
mass distribution (MMD), followed by further analysis of these separated fractions with conventional
analytical techniques. The combination of preparative temperature rising elution fractionation (TREF)
with several other analytical techniques have been reported for the thorough characterization of this
material. However, even the combinations of these methods were of limited value due to the complex
nature of this polymer. Therefore, novel analytical approaches are needed for a more detailed
compositional analysis of IPCs.
This work describes a number of multidimensional analytical techniques that are based on the
combination of fractionation and hyphenated techniques. Firstly, preparative TREF was combined
with high temperature size exclusion chromatography-FTIR (HT SEC-FTIR), HT SEC-HPer DSC
(High Performance Differential Scanning Calorimetry) and high temperature two-dimensional liquid
chromatography (HT 2D-LC) for the comprehensive analysis of a typical impact polypropylene
copolymer and one of its midelution temperature TREF fractions. HT SEC-FTIR analysis provided
information regarding the chemical composition and crystallinity as a function of molar mass. Thermal
analysis of selected SEC fractions using a novel DSC method - High Speed or High Performance
Differential Scanning Calorimetry (HPer DSC) - that allows measuring of minute amounts of material
down to micrograms, yielded the melting and crystallization behaviour of these fractions which is
related to the chemical heterogeneity of this complex copolymer. High temperature 2D-LC analysis
provided the complete separation of this TREF fraction according to the chemical composition of each
component along with its molar mass distribution. In a second step, the compositional characterization by advanced thermal analysis (HPer DSC, Flash DSC 1, and solution DSC) of the
TREF-SEC fractions was extended to all semi-crystalline and higher temperature TREF fractions. By
applying HPer DSC at scan rates of 5−200°C/min and Flash DSC 1 at scan rates of 10−1000°C/s,
the metastability of one of the fractions was studied in detail. DSC measurements of TREF-SEC
cross-fractions at high scan rates in p-xylene successfully connected reversely to the slow scan rate
in TREF elution, if corrected for recrystallization. Finally, the exact chemical structure of all HT HPLC
separated components was determined by coupling of HT HPLC with FTIR spectroscopy via an LCTransform
interface. This novel approach revealed the capability of this hyphenated technique to
determine the exact chemical composition of the individual components in the complex TREF
fractions of IPCs. The HT HPLC–FTIR results confirmed the separation mechanism in HPLC using a
solvent gradient of 1-decanol/TCB and a graphitic stationary phase at 160°C. FTIR analysis provided
information on the ethylene and propylene contents of the fractions as well as on the ethylene and
propylene crystallinities. / AFRIKAANSE OPSOMMING: Impak Polipropileen Kopolimere (IPKe) is uiters komplekse materiale, bestaande uit 'n mengsel van
polipropileen homopolimeer en kopolimere met verskillende komonomeer (etileen) inhoud en
chemiese samestelling verspreiding. IPKe kan slegs doeltreffend ontleed word deur multidimensionele
analitiese benaderings te volg. Hiervoor moet die individuele komponente aanvanklik
eers geskei word volgens enige van hul molekulêre eienskappe, hetsy deur die chemiese
samestelling verspreiding (CSV) of molêre massa verspreiding (MMV), gevolg deur 'n verdere
ontleding van hierdie geskeide fraksies met konvensionele analitiese tegnieke. Die kombinasie van
voorbereidings temperatuur-verhogings eluasie fraksionering (TVEF) met verskeie ander analitiese
tegnieke is gerapporteer vir die deeglike karakterisering van hierdie materiaal. Maar selfs die
kombinasies van hierdie metodes was van beperkte waarde as gevolg van die komplekse aard van
hierdie polimeer. Daarom word nuwe analitiese benaderings benodig vir 'n meer gedetailleerde
komposisionele ontleding van IPKe.
Hierdie studie beskryf 'n aantal multidimensionele analitiese tegnieke wat gebaseer is op die
kombinasie van fraksionering en gekoppelde tegnieke. Eerstens is voorbereidings TVEF gekombineer
met hoë temperatuur grootte-uitsluitingschromatografie-FTIR (HT GUC-FTIR), HT GUC-HPer DSK en
hoë temperatuur twee-dimensionele vloeistof chromatografie (HT 2D-VC) vir die omvattende
ontleding van 'n tipiese impak polipropileen kopolimeer en een van sy mid-eluasie temperatuur TVEF
fraksies. HT GUC-FTIR analiese het inligting verskaf met betrekking tot die chemiese samestelling en
kristalliniteit as 'n funksie van molêre massa. Termiese analiese van geselekteerde GUC fraksies deur
gebruik te maak van 'n nuwe-DSK metode - Hoë Spoed of Hoë Prestasie Differensïele skandeer
kalorimetrie (HPer DSK) - wat die meting van klein hoeveelhede materiaal tot by mikrogram
hoeveelhede toelaat, het die smelt en kristallisasie gedrag van hierdie fraksies bepaal wat verwant is
aan die chemiese heterogeniteit van hierdie komplekse kopolimeer. Hoë temperatuur 2D-LC analiese
het die volledige skeiding van hierdie TVEF fraksie volgens die chemiese samestelling van elke
komponent saam met die molêre massa verspreiding moontlik gemaak. In 'n tweede stap, is die komposisionele karakterisering deur gevorderde termiese analiese (HPer DSK, Flash DSK 1 en
oplossing DSK) van die TVEF-GUC fraksies uitgebrei na alle semi-kristallyne en hoër temperatuur
TVEF fraksies. Deur die gebruik van HPer DSK, teen ’n skandeerspoed van 5-200°C / min, en Flash
DSK 1, teen ’n skandeerspoed van 10-1000°C / s, is die meta-stabiliteit van een van die fraksies in
detail bestudeer. DSK metings van TVEF-GUC kruis-fraksies by 'n hoë skandeeerspoed in p-xyleen
het suksesvol omgekeerd verbind aan die stadige skandeerspoed in TVEF eluasie, wanneer
gekorrigeer vir dekristallisatie. Ten slotte is die presiese chemiese struktuur van al die HT HPVC
geskeide komponente bepaal deur die koppeling van HT HPVC met FTIR spektroskopie deur middel
van 'n LC-transform-koppelvlak. Hierdie nuwe benadering het die vermoë van die gekoppelde tegniek
om die presiese chemiese samestelling van die individuele komponente in die komplekse TVEF
fraksies of IPKe te bepaal aan die lig gebring. Die HT HPVC-FTIR resultate het die
skeidingsmeganisme in HPVC bevestig deur die gebruik van ’n oplosmiddelgradiënt van 1-dekanol/TCB en 'n graphitiese stasionêre fase by 160°C. FTIR analiese verskaf inligting in verband
met die etileen en propileen inhoud van die fraksies sowel as die etileen en propileen krystalliniteit.
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Stanovení acetylcholinu pomocí LC-MS ve vzorcích mozkových mikrodialyzátů LC-MS/MS / Stanovení acetylcholinu pomocí LC-MS ve vzorcích mozkových mikrodialyzátů LC-MS/MSVrobel, Ivo January 2013 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Analytical Chemistry Candidate: Ivo Vrobel Supervisors: Prof. RNDr. Petr Solich, CSc; Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague Prof. Seppo Auriola, MSc.(Chem.) Marko Lehtonen; Department of Pharmaceutical Chemistry, School of Pharmacy, University of Eastern Finland in Kuopio Title of master's thesis: LC-MS/MS analysis of acetylcholine in brain microdialysis samples Novel fast and simple LC-MS/MS method of ACh quantification in brain microdialysis samples utilizing stable-isotope-labeled IS was developed. The chromatographic step is based on revered-phase mode of pentafluorophenylpropyl (PFPP) column. The satisfactory retention of ACh is achieved with highly aqueous mobile phase containing 0.05% of the ion-pairing agent TFA and 4% of ACN in 4 min analytical run. Ionization of ACh and IS with low background noise and tolerant towards use of TFA was performed with atmospheric pressure thermospray ionization (APTSI). The selectivity of ACh and IS detection was obtained by SRM modes of MS/MS in the linear ion trap mass analyzer. The performance of developed method was cross validated to the validated method used in the laboratory for ACh measurements. The set of microdialysis...
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Lipidová pojiva v malířských dílech: možnosti identifikace vysychavých olejů pomocí kapalinové chromatografie / Lipidic binders in artworks: possible identification of the used drying oils by liquid chromatographyPecháčková, Soňa January 2012 (has links)
This work is concerned with lipidic substances, in particular vegetable oils, used as pigment binders or as a protective varnishes for finishing artwork. The introduction reviews the recent knowledge of this subject, in particular with respect to the identification of the most used drying oils, and of the methods to study their changes in the course of time. Both can be achieved using determination of the relative representation of fatty acids, most characteristic being the ratio of stearic/palmitic a oleic/palmitic acids. This parameter is changing as the artwork is getting older and the oils are drying. Because of the availability of the instrumentation needed, we have chosen the high- performance liquid chromatography method for further experimental work. The first step was optimalization of the analytical method by standards of fatty acids. For derivatization of fatty acids, reagents 2,4-dinitrophenylhydrazine and 2-nitrophenylhydrazine were examined. Whereas we were unable to get any results with the first one (the method based on the article: Bravo, B. et al., Talanta 64, 1329-1334, 2004) for unknown reasons, good results were obtained with the second one. Derivates of fatty acids have been analyzed by high performance liquid chromatography (HPLC) on column with revesed phase (C18). The...
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Studie inkluzních komplexů pesticidů s kukurbiturily / Study of inclusion complexes of pesticides with cucurbiturilsSmitka, Jaroslav January 2013 (has links)
In this work we report the formation of inclusion complexes of the pesticides 1-naphthylacetic acid, 1-naphthylacetamide, napropamide and carbaryl with cucurbit[n]uril (n=7 and 8) and -cyclodextrin hosts. We also report results of the photochemistry of these compounds when free in aqueous solution and included within these nano-containers. The formation of inclusion complexes was studied by electrospray ionization mass spectrometry (ESI-MS) which gave us information about stoichiometry of the complexes and about their reactivity in the gas phase. The photodecomposition and formation of products was followed by high performance liquid chromatography coupled to both mass spectrometry (HPLC-MS) and UV/VIS detector, and spectrophotometry. The studied CBs and their host-guest complexes were readily detected in the gas phase by ESI-MS, mainly as single and double charged ions containing either H+ , Na+ or K+ . The assignments were made based on the m/z values of the observed signals and further confirmed by fragmentation (tandem mass spectrometry - MSn ). All pesticides formed 1:1 (host:guest) complexes. Carbaryl, napropamide and 1-naphthylacetamide also formed 1:2 (host:guest) complexes. Under some solution chemistry conditions, namely for concentrations of cucurbiturils above 50 µM and at low acid and...
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