Horseradish peroxidase activity in a reverse catanionic microemulsion.

Sekh Mahiuddin; Audrey Renoncourt; Pierre Bauduin; Didier Touraud; Werner Kunz

doi:10.1021/la047161r

Home/Archive/PubMed

PubMed · 15924447

Horseradish peroxidase activity in a reverse catanionic microemulsion.

Sekh Mahiuddin·Audrey Renoncourt·Pierre Bauduin·Didier Touraud·Werner Kunz

View original source ↗Export metadata ↓

Abstract

In this paper we present the first results of enzymatic activities in a reverse microemulsion medium based on a mixture of an anionic and a cationic surfactant, called catanionic microemulsion. The studied system is composed of sodium dodecyl sulfate (SDS)/dodecyltrimethylammonium bromide (DTAB)/n-hexanol/citrate buffer/n-dodecane, with high SDS/(SDS + DTAB) weight fractions. It turns out that the results are similar to those obtained in classical reverse microemulsions, except that the presence of DTAB exerts an inhibiting effect on the enzyme. Nevertheless, enzymatic superactivities are found even at a DTAB to total surfactant ratio of 15%, corresponding to 3% weight fraction of cationic surfactant in the microemulsion. The influence of pH and hexanol content on the enzymatic activities is also studied.

Explore related subjects

Cations Emulsions Hexanols Horseradish Peroxidase Hydrogen-Ion Concentration Microchemistry Sodium Dodecyl Sulfate Journal Article Research Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Sekh Mahiuddin, Audrey Renoncourt, Pierre Bauduin, Didier Touraud, Werner Kunz. 2005-06-07. Horseradish peroxidase activity in a reverse catanionic microemulsion.. https://doi.org/10.1021/la047161r

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Cationic surfactant changes the morphology of DNA molecules.

The effect of cetyltrimethylammonium bromide (CTAB), a cationic surfactant, was investigated on the aggregated form of DNA molecules in water at a given temperature. CTAB caused changes in the aggregated form of DNA molecules from loosely packed spherical to rodlike through toroidal one with increasing concentration below the critical micelle concentration (CMC). The change was suggested to arise from the ion complex formation between CTAB and DNA molecules due to the electrostatic interaction, thereby reducing the surface charge and solubility in water of the latter.

Cations↗

PubMed2007

Lack of association between a cationic protein and a cationic fluorosurfactant.

Surface tension, 19F and 1H NMR spectroscopy, and cryotransmission electron microscopy are used to characterize the state of association in aqueous solutions of a fluorosurfactant CF3(CF2)nSO2NH(CH2)3-4N(CH3)3+ I- (n = 8, 6) with and without lysozyme added. In the absence of lysozyme, we find monomers, small aggregates, and large vesicles to coexist, with the individual fluorosurfactant molecules exchanging slowly (>1 ms) among those states. When both lysozyme and fluorosurfactant are present in the solution, they have no measurable influence on the physical state of the other. In contrast, a hydrogenated cationic surfactant with the same headgroup, hexadecyltrimethylammonium bromide, is shown to associate to lysozyme.

Cations↗

PubMed2007

Self-assembly, DNA complexation, and pH response of amphiphilic dendrimers for gene transfection.

Cationic lipids and polymers are routinely used for cell transfection, and a variety of structure-activity relation data have been collected. Few studies, however, focus on the structural aspects of self-assembly as a crucial control parameter for gene delivery. We present here the observations collected for a set of cationic dendritic amphiphiles based on a stiff tolane core (1-4) that are built from identical subunits but differ in the number and balance of their hydrophobic and cationic hydrophilic moieties. We established elsewhere that vectors 3 and 4 have promising transfection properties. Scanning probe microscopy (AFM, STM), cryo-transmission electron microscopy (cryo-TEM), and Langmuir techniques provide insight into the self-assembly properties of the molecules under physiological conditions. Furthermore, we present DNA and pH "jump" experiments where we study the response of Langmuir films to a sudden increase in DNA concentration or a drop in pH. We find that the primary self-assembly of the amphiphile is of paramount importance and influences DNA binding, serum sensitivity, and pH response of the vector system.

Cations↗