Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Detection of substances with alcoholic or phenolic hydroxyl groups by generation of hydrogen peroxide with imidazole and peroxyoxalate chemiluminescence (1995)
    New York : Wiley-Blackwell
    Journal of Bioluminescence and Chemiluminescence 10 (1995), S. 339-344 
    Details
    ISSN: 0884-3996
    Keywords: imidazole ; peroxyoxalate chemiluminescence ; sugar ; monophenol ; polyphenol ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: On-line detection of substances with an alcoholic or phenolic hydroxyl group using imidazole and peroxyoxalate chemiluminescence was investigated qualitatively using a flow-injection method. The substances tested included six polyphenols, five monophenols and six sugars. After incubation at 80°C with an imidazole buffer (pH 9.5) the substances were detected by peroxyoxalate chemiluminescence. The polyphenols tested (e.g., pyrogallol, purpurogallin, and dopamine) showed the strongest light emission. The sugars with hydroxyl groups (e.g., fructose and lactose) and the monophenols (e.g., phenol, serotonin, and β-estradiol) produced only a weak light emission. Reaction of hydroxyl compounds and imidazole generated hydrogen peroxide. Imidazole served two roles, it catalysed the reaction with the hydroxyl compound and initiated peroxyoxalate chemiluminescence on-line. A novel reactor formed by packing glass beads into a flow cell (Teflon) of a chemiluminometer improved the sensitivity of light detection.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bio.1170100606
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Imaging of chemiluminescent reactions in mesoscale silicon-glass microstructures (1994)
    New York : Wiley-Blackwell
    Journal of Bioluminescence and Chemiluminescence 9 (1994), S. 135-138 
    Details
    ISSN: 0884-3996
    Keywords: Silicon ; chemiluminescence ; microchannels ; imaging ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Chemiluminescent reactions in mesoscale analytical structures (chips) containing micrometer-sized interconnecting channels and chambers (pL-nL total volume) were imaged. The chips were fabricated by bonding Pyrex glass to etched pieces of silicon using a high-temperature diffusive bonding technique. In initial experiments light emission from an enhanced chemiluminescent horseradish peroxidase reaction and from a peroxyoxalate reaction contained in straight channels (300 μm wide × 20μ deep; volume 70.2 nL) and open chambers (812 μm wide, 400 μm deep, 5.2 mm long) linked by channels (100μm wide, 20 μm deep) to an exit and entry port were studied using a specially modified microplate holder and an Amerlite microplate luminometer. Light emission from more complex structures (two chambers interconnected by a branching channel 100 μm wide, 20 μm deep) filled with a solution containing alkaline phosphatase, Emerald, and CSPDTM was imaged using a Photometrics Star 1 CCD camera. Detailed investigation of the detection and spatial resolution of the signal was performed on a Berthold Luminograph LB 980 using both the enhanced chemiluminescent horseradish peroxidase reaction and a peroxyoxalate reaction. We successfully resolved light emission from silicon structures with dimensions 100 μm wide and 20 μm deep. These simple silicon structures served as models for more complex designs that will be used for simultaneous multi-analyte assays in which an imaging system resolves and quantitates light emission from different locations on a silicon-glass analytical device.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bio.1170090306
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    New enhancers for the chemiluminescent peroxidase catalysed chemiluminescent oxidation of pyrogallol and purpurogallin (1995)
    New York : Wiley-Blackwell
    Journal of Bioluminescence and Chemiluminescence 10 (1995), S. 151-156 
    Details
    ISSN: 0884-3996
    Keywords: enhancers ; boronic acids ; peroxidase chemiluminescence ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: The effects of various boronate compounds, 4-biphenylboronic acid, 4-bromobenzeneboronic acid, trans-4-(3-propionic acid)phenylboronic acid and 4-iodophenylboronic acid, on the horseradish peroxidase (HRP) catalysed chemiluminescent oxidation of pyrogallol and purpurogallin by peroxide were investigated. trans-4-(3-Propionic acid)phenylboronic acid produced a 13.7-fold enhancement in the peak light emission from the chemiluminescent HRP catalysed pyrogallol reaction (detection limit for HRP 〈 1.25 fmol). At low enhancer concentration a single peak of light emission was observed and as the enhancer concentration increased the time to peak light emission became progressively longer. The chemiluminescence showed two peaks at higher concentrations (〉 54.3 μmol/L) and the individual peak times depended upon the concentration of the enhancer. All of the boronates enhanced peak light emission in the chemiluminescent HRP catalysed purpurogallin reaction. 4-Biphenylboronic acid was the most effective and it enhanced peak light emission 314-fold. The practical detection limit for HRP (Type VIA) using this enhancer was 4.18 pmol (peak emission at 20 minutes). This compound also enhanced peak light emission 232-fold from a chemiluminescent HRP-purpurogallin reaction in which molecular oxygen replaced peroxide as the oxidant.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bio.1170100303
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Determination of urinary free cortisol by high performance liquid chromatography with sulphuric acid-ethanol derivatization and column switching (1992)
    New York, NY : Wiley-Blackwell
    Biomedical Chromatography 6 (1992), S. 109-114 
    Details
    ISSN: 0269-3879
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A rapid and highly sensitive determination method for urinary free cortisol has been developed using reversed phase high performance liquid chromatography (HPLC) with a precolumn for sulphuric acid-ethanol fluorescence derivatization and column switching. Urinary cortisol, eluted from the octadecylsilane-bonded silica (ODS) minicolumn with 90% aqueous ethanol, was derivatized with the addition of sulphuric acid only at ambient temperature. Cortisol derivatives injected directly onto the ODS precolumn were purified on-line. After switching the columns, the cortisol derivative was separated on an ODS analytical column with a retention time of 15.3 min and monitored at an emission wavelength of 520 nm (exitation wavelength of 365 nm) to decrease the detection limit to 0.26 μg/dL (signal-to-noise ratio = 3). The automated HPLC operation resulted in good reproducibility and recovery of the stable cortisol derivative at 5°C.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bmc.1130060302
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...