Biomedical subjects

V Dupres

Publications and source records attributed to V Dupres.

3 recordsLinked to original sources

PubMed2005

Sample preparation procedures for biological atomic force microscopy.

Since the late 1980s, atomic force microscopy (AFM) has been increasingly used in biological sciences and it is now established as a versatile tool to address the structure, properties and functions of biological specimens. AFM is unique in that it provides three-dimensional images of biological structures, including biomolecules, lipid films, 2D protein crystals and cells, under physiological conditions and with unprecedented resolution. A crucial prerequisite for successful, reliable biological AFM is that the samples need to be well attached to a solid substrate using appropriate, nondestructive methods. In this review, we discuss common techniques for immobilizing biological specimens for AFM studies.

Animals↗

PubMed2002

Variation of the in-plane structure with depth revealed by grazing incidence x-ray diffraction in a thin Langmuir-Blodgett film.

Grazing incidence x-ray diffraction is used to characterize the molecular arrangement of ultrathin Langmuir-Blodgett (LB) multilayers. Using two angles of incidence of the beam allowing its penetration either throughout the complete depth of the film or only through the external layers, we show that it is possible to discriminate between the molecular packing of the deeper monolayers and that of the external monolayers of the LB film.

Journal Article↗

PubMedDate not supplied

Surface enhanced Raman scattering of a lipid Langmuir monolayer at the air-water interface.

Surface enhanced Raman spectra were recorded from a phospholipid monolayer directly at the air-water interface. We used an organized monolayer of negatively charged tetramyristoyl cardiolipins as a template for the electrochemical generation of silver deposits. This two-dimensional electrodeposition of silver under potentiostatic control was the substrate for enhancement of Raman spectra. We report the optimized conditions for the Raman enhancement, the microscopic observations of the deposits, and their characterization by atomic force microscopy. Laser excitation at 514.5 nm leads to intense and reproducible surface enhanced Raman scattering spectra recorded in situ from one monolayer of cardiolipin, using 0.5 mol % of 10N nonyl acridine orange or 5 mol % of acridine in the film, and demonstrates the possibility of estimating the pH at the metal/phospholipidic film interface.

Acridine Orange↗