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
    Influence of various salts on the reversed-phase retention of some dansylated amino acids in TLC (1993)
    Springer
    Chromatographia 36 (1993), S. 302-306 
    Details
    ISSN: 1612-1112
    Keywords: Thin-layer chromatography ; Dansylated amino acids ; Salting-out effect ; Alkali metal chlorides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The retention of 14 dansylated amino acid derivatives was determined using aqueous LiCl, NaCl, KCl, RbCl and CsCl solutions as eluents in reversed-phase thinlayer chromatography. The salts exerted typical salting-out effects, the retention of each dansylated amino acid increased with increasing concentration of salt in the eluent. This effect has been tentatively explained by the suppression of the dissociation of the polar groups in the solute molecules resulting in increased apparent lipophilicity. The correlation between the increased retention of dansyl amino acids and the salt concentration was found to be linear. The hydrated radii and energy of hydration of cations as well as the hydrophobicity of free amino acids and the pK value of the α-amino groups simultaneously influenced the retention.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02263882
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Characterization of some new polysiloxane stationary phases by principal component analysis (1994)
    Springer
    Chromatographia 38 (1994), S. 227-231 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Stationary phase characterization ; Principal component analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary In this study, several new stationary phases were characterized by principal component analysis. Fourteen new stationary phases, including substituted phenyl and oligoethyleneoxide functionalities on polysiloxane polymers, were tested and compared to three well known stationary phases. The main features of these phases were studied using a series of test solutes of varying chemical characteristics representing the data set for principal component analysis. Two principal compounds were found to account for 99.20% of the variance (the first accounted for 94.96% and the second for 4.24%). The data were represented as a two-dimensional map for visual representation of the characteristics of these stationary phases. The first principal component represented a selectivity based on polarity (r2=0.998), while the second showed Lewis acid-base characteristics of the phases. Polarizable and amphoteric characteristics of these phases also became evident using this evaluation method.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02290341
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Nonionic tensides modify papain structure and proteolytic activity (1990)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 10 (1990), S. 85-92 
    Details
    ISSN: 0138-4988
    Keywords: Life Sciences ; Life Sciences (general)
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: The effect of 33 polyethoxylated nonionic tensides with various hydrophobic moieties was studied on the proteolytic activity and phase transition behaviour of papain. Tensides with longer ethyleneoxide chain markedly increased the phase transition temperatures of papain indicating possible hydrogen bond formation between the hydrophilic ethyleneoxide chain and the polar substructures of papain. The character of lipophilic moiety of tensides influences also each physicochemical parameter of papain suggesting the existence of hydrophobic interactions too. The significant positive linear correlations between the activity increasing and structure stabilizing effects of tensides make probably that the structure modification of papain accounts for its enchanced proteolytic activity.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/abio.370100122
    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...