Protein-Drug Interaction in the Nanocomposites Prepared by UV and IR Pulsed Laser Deposition

2004 ◽  
Vol 849 ◽  
Author(s):  
J. Sagawa ◽  
S. Nagare ◽  
M. Senna
Keyword(s):  
Secondary Structure ◽  
Pulsed Laser Deposition ◽  
Laser Fluence ◽  
Vibrational Excitation ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Ir Laser ◽  
Ft Ir ◽  
Β Sheet ◽  
Protein Bovine Serum Albumin

ABSTRACTProtein (bovine serum albumin; BSA)-drug (indomethacin; IM) nanocomposites were prepared by pulsed laser deposition (PLD) at two wavelengths, infrared (1064nm) and ultraviolet (266nm), from uniformly dispersed mixture of BSA and IM as a target. Composite particulates under 50nm were obtained with the coexistence of larger agglomerates over 200nm. Primary structure of BSA is preserved after laser irradiation by both wavelengths. Effects of electronic and vibrational excitation by UV and IR laser respectively on the secondary structure of the nanocomposites were examined by Fourier transform infrared spectroscopy (FT-IR). Chemical shift towards lower wavenumber and a broadening of the amide I band due to PLD treatment were observed by FT-IR. From curve fitting of the amide I into five components, we found the decrease in the ratio of α-helical / β-sheet components with increasing the laser fluence. The secondary structure of BSA is more sensitive to the laser fluence than the wavelength.

Preparation and Microstructure Control of Protein Thin Films Deposited by Pulsed Laser Deposition and Via Colloid Chemical Routes

2003 ◽  
Vol 788 ◽  
Author(s):  
Sayuri Nakayama ◽  
Ichiro Taketani ◽  
Sanshiro Nagare ◽  
Mamoru Senna
Keyword(s):  
Thin Film ◽  
Secondary Structure ◽  
Pulsed Laser Deposition ◽  
Power Density ◽  
Laser Power ◽  
Pulsed Laser ◽  
Laser Power Density ◽  
Laser Deposition ◽  
Random Coil ◽  
Β Sheet

ABSTRACTProtein thin film (mainly silk fibroin) was prepared by pulsed laser deposition (PLD) with 1064nm IR-beam and via colloid chemical routes. Thickness, surface roughness, and microstructures of the deposited film were examined by quartz crystal microbalance sensor, field emission scanning electron microscope (FE-SEM), and atomic force microscope (AFM). The laser power density was varied systematically for PLD to control the microstructures of the film and the secondary structure (β-sheet, α-helix, or random coil) of the protein. Secondary structure of the target and film was examined by FT-IR. Films prepared by PLD comprise by agglomerated particles with their primary particle size around 30nm. The size of the primary particles was uniform, especially for the film prepared at low laser power density. At low laser power density, proportion of β-sheet increased and that of random coil decreased. Proportion of random coil was also increased by the wet colloidal process. PLD with low power density is most suitable to preserve the secondary structure in the protein thin film.

Temperature Dependent Micro-Raman Scattering of Sr0.35Ba0.65TiO3 Film Grown by Pulsed Laser Deposition

1995 ◽  
Vol 401 ◽  
Author(s):  
Sampriti Sen ◽  
E. Ching-Prado ◽  
A. Reynés-Figueroa ◽  
R. S. Katiyar ◽  
J. S. Horwitz ◽  
...  
Keyword(s):  
Single Crystal ◽  
Pulsed Laser Deposition ◽  
Ceramic Material ◽  
Normal Modes ◽  
Pulsed Laser ◽  
Rhombohedral Phase ◽  
Laser Deposition ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
Ft Ir

AbstractA film of Sr0.35Ba0.65TiO3 (SBT) has been grown in situ by pulsed laser deposition on (001) LaAlO3 single crystal. From X-ray diffraction studies the sample is found to be in single phase and well oriented. Raman spectrum of the SBT film shows bands around 178, 219, 296, 513, 571 and 741 cm”. The spectrum is similar to that found in SBT ceramic material, but the frequencies of the phonons are shifted. This can be explained if the film is under stress due to the presence of defects. The bands at 296 and 741cm−1 correspond to the B1 and A1(LO) normal modes of the BaTiO3 (BT) system, and they are representative of the BT tetragonal phase, which at first glance appears to contradict earlier structural symmetry assignment for SBT(x=0.35) film at room temperature. Micro-Raman measurements from different regions of the film indicate that the SBT film is homogeneous. The bands at 296 and 741 cm−1 are broader in comparison to those in BT single crystal and SBT ceramic material. Temperature dependent halfwidths of these modes suggest strong contribution of defects. Temperature dependent results are discussed in terms of anharmonic contributions involving three and four phonon processes as well as defects. Also, the orthorhombic and rhombohedral phase transitions are discussed. Finally, SEM/EDAX and FT-IR techniques have been used for the structural characterization.

scholarly journals Effect of laser fluence on structural and optical properties of CuxS films grown by pulsed laser deposition at different wavelengths

2020 ◽  
Vol 7 (1) ◽  
pp. 015908
Author(s):  
P E Rodríguez-Hernández ◽  
J G Quiñones-Galván ◽  
M Meléndez-Lira ◽  
J Santos-Cruz ◽  
G Contreras-Puente ◽  
...  
Keyword(s):  
Optical Properties ◽  
Pulsed Laser Deposition ◽  
Laser Fluence ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Structural And Optical Properties

Modeling of Film Growth in Pulsed Laser Deposition

1995 ◽  
Vol 397 ◽  
Author(s):  
M. Tyunin
Keyword(s):  
Growth Rate ◽  
Pulsed Laser Deposition ◽  
Laser Fluence ◽  
Film Growth ◽  
Surface Film ◽  
Substrate Surface ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Ambient Gas ◽  
Deposited Films

ABSTRACTFilm growth in pulsed laser deposition (PLD) is described as a process of sorption of ablated species on the substrate surface. Film growth rate and composition are qualitatively analyzed as a function of laser fluence and ambient gas pressure. As an example, analysis of the film composition is carried out for BiSrCaCuO and PbZrTiO pulsed laser deposited films.

Pulsed laser deposition of a-CNx:H films: the role of target-to-substrate distance and laser fluence

2000 ◽  
Vol 154-155 ◽  
pp. 454-457 ◽  
Author(s):  
P González ◽  
R Soto ◽  
B León ◽  
M Pérez-Amor ◽  
T Szörényi
Keyword(s):  
Pulsed Laser Deposition ◽  
Laser Fluence ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Substrate Distance
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