A new instrumental approach to recycling HPLC is described. The concept is based on fast reintroduction of incremental peak sections back onto the separation column. The re-circulation is performed within a closed loop containing only the column and two synchronized switching valves. By having HPLC pump out of the cycle, the method minimizes peak broadening due to dead volume. As a result the efficiency is dramatically increased allowing for the most demanding analytical applications. In addition, a parking loop is employed for temporary storage of analytes from the middle section of the separated mixture prior to their recycling.
- Klíčová slova
- Circulation chromatography, Closed loop recycling, Peak recycling, Recycle system, Sample recycler,
- MeSH
- benzenové deriváty chemie izolace a purifikace MeSH
- polycyklické sloučeniny chemie izolace a purifikace MeSH
- protiproudá chromatografie MeSH
- recyklace * MeSH
- stereoizomerie MeSH
- vysokoúčinná kapalinová chromatografie přístrojové vybavení metody MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- benzenové deriváty MeSH
- helicenes MeSH Prohlížeč
- polycyklické sloučeniny MeSH
In this short communication we report optimized procedures for the chiral separation of non-charged [6]helicene (1) and cationic derivative 1-butyl-3-(2-methyl[6]helicenyl)-imidazolium bromide (2) using high-performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC) methods. The possibility of using capillary electrophoresis (CE) was also tested. The satisfactory results were obtained with SFC, where the highly selective resolution of four enantiopure 1 and 2 helicenes was achieved in a single run within 5min. The semi-preparative procedure for the isolation of P and M enantiomers of compound 2, including circular dichroism data, is reported here for the first time. The results could be used in further separations and analytical applications targeting carbohelicenes vs. positively charged helicene derivatives.
- Klíčová slova
- Capillary electrophoresis, Chirality, Helicene, High-performance liquid chromatography, P/M enantiomer, Supercritical fluid chromatography,
- MeSH
- elektroforéza kapilární metody MeSH
- polycyklické sloučeniny chemie izolace a purifikace MeSH
- stereoizomerie MeSH
- superkritická fluidní chromatografie metody MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- helicenes MeSH Prohlížeč
- polycyklické sloučeniny MeSH
The aim of the present study was to determine the structural requirements for dibenzocyclooctadiene lignans essential for P-glycoprotein inhibition. Altogether 15 structurally related lignans isolated from Schisandra chinensis or prepared by modification of their backbone were investigated, including three pairs of enantiomers. P-Glycoprotein inhibition was quantified using a doxorubicin accumulation assay in human promyelotic leukemia HL60/MDR cells overexpressing P-glycoprotein. A preliminary quantitative structure-activity relationship analysis revealed three main structural features involved in P-glycoprotein inhibition: a 1,2,3-trimethoxy moiety, a 6-acyloxy group, and the absence of a 7-hydroxy group. The most effective inhibitors, (-)-gomisin N (1) and (+)-deoxyschizandrin [(+)-2], were selected for further evaluation of their effects. Both these lignans restored the cytotoxic effect of doxorubicin in HL60/MDR cells and when combined with a subtoxic concentration of this compound increased the proportion of G2/M cells significantly, which is a usual response to treatment with this anticancer drug.
- MeSH
- cyklooktany * chemie izolace a purifikace farmakologie MeSH
- doxorubicin farmakologie MeSH
- kontrolní body fáze G2 buněčného cyklu účinky léků MeSH
- kvantitativní vztahy mezi strukturou a aktivitou MeSH
- lidé MeSH
- lignany * chemie izolace a purifikace farmakologie MeSH
- molekulární struktura MeSH
- P-glykoproteiny antagonisté a inhibitory MeSH
- polycyklické sloučeniny * chemie izolace a purifikace farmakologie MeSH
- Schisandra chemie MeSH
- semena rostlinná chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Rusko MeSH
- Názvy látek
- cyklooktany * MeSH
- dibenzocyclooctadiene lignan MeSH Prohlížeč
- doxorubicin MeSH
- lignany * MeSH
- P-glykoproteiny MeSH
- polycyklické sloučeniny * MeSH
- schizandrin A MeSH Prohlížeč
- schizandrin B MeSH Prohlížeč
Fractions containing polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were extracted from river sediments by various extraction methods. The amount of individual pollutants was determined analytically and data compared with biological assays. These were based on the induction of cytochrome P450 1A1 (CYPIA1) after treatment with sediment fractions in two different biological model systems, a mouse hepatoma cell line Hepa-1 and a chick embryo. In the hepatoma cell culture Hepa-1 significant correlations with analytical results were found for fractions containing PCDD/Fs and planar and mono-ortho-chlorinated PCBs. However for PAH fraction an undesirable decrease of P450 1A1 induction was observed in higher concentrations of this fraction. This decrease was not observed in the chick embryo liver microsomes and biological responses towards the PAH fractions correlated with analytical data. Comparative investigations demonstrated that the chicken embryo hepatic microsomes were more sensitive for PAHs, and the hepatoma cell line Hepa-1 for PCDD/Fs and planar and mono-ortho-chlorinated PCBs.
- MeSH
- benzofurany analýza izolace a purifikace toxicita MeSH
- biotest MeSH
- chemické látky znečišťující vodu analýza izolace a purifikace toxicita MeSH
- cytochrom P-450 CYP1A1 MeSH
- enzymová indukce účinky léků MeSH
- hepatocelulární karcinom patologie MeSH
- jaterní mikrozomy účinky léků enzymologie MeSH
- játra účinky léků embryologie enzymologie MeSH
- kuřecí embryo MeSH
- monitorování životního prostředí MeSH
- myši MeSH
- nádorové buňky kultivované MeSH
- nádory jater patologie MeSH
- oxidoreduktasy biosyntéza MeSH
- polychlorované bifenyly analýza izolace a purifikace toxicita MeSH
- polychlorované dibenzodioxiny analogy a deriváty analýza izolace a purifikace toxicita MeSH
- polychlorované dibenzofurany MeSH
- polycyklické sloučeniny analýza izolace a purifikace toxicita MeSH
- senzitivita a specificita MeSH
- sladká voda MeSH
- systém (enzymů) cytochromů P-450 biosyntéza MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Názvy látek
- benzofurany MeSH
- chemické látky znečišťující vodu MeSH
- cytochrom P-450 CYP1A1 MeSH
- oxidoreduktasy MeSH
- polychlorované bifenyly MeSH
- polychlorované dibenzodioxiny MeSH
- polychlorované dibenzofurany MeSH
- polycyklické sloučeniny MeSH
- systém (enzymů) cytochromů P-450 MeSH
The antimicrobial action of 11 compounds involving guaiacyl- and syringyl-like structures (low-molecular-weight part of lignin), gallic acid and its derivatives, cinnamic acid and its derivatives, veratric acid, anisic acid and crotonic acid (a total of 25 compounds) against bacteria, yeast-like organisms and protozoa was examined. Aromatic compounds modified in the C-side chain and aldehydes were effective preferentially against Trichomonas vaginalis, whereas against bacteria and yeast-like organisms eugenol was the most effective inhibitor.
- MeSH
- antibakteriální látky MeSH
- antiinfekční látky * MeSH
- léčivé rostliny * MeSH
- mikrobiální testy citlivosti MeSH
- polycyklické sloučeniny izolace a purifikace farmakologie MeSH
- Pseudomonas aeruginosa účinky léků MeSH
- Staphylococcus aureus účinky léků MeSH
- Trichosporon účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antibakteriální látky MeSH
- antiinfekční látky * MeSH
- polycyklické sloučeniny MeSH
