Cytotoxicity Study of UV-Laser-Irradiated PLLA Surfaces Subjected to Bio-Ceramisation: A New Way towards Implant Surface Modification

In this research we subjected samples of poly(L-lactide) (PLLA) extruded film to ultraviolet (193 nm ArF excimer laser) radiation below the ablation threshold. The modified film was immersed in Simulated Body Fluid (SBF) at 37 °C for 1 day or 7 days to obtain a layer of apatite ceramic (CaP) coating on the modified PLLA surface. The samples were characterized by means of optical profilometry, which indicated an increase in average roughness (Ra) from 25 nm for the unmodified PLLA to over 580 nm for irradiated PLLA incubated in SBF for 1 day. At the same time, the water contact angle decreased from 78° for neat PLLA to 35° for irradiated PLLA incubated in SBF, which suggests its higher hydrophilicity. The obtained materials were investigated by means of cell response fibroblasts (3T3) and macrophage-like cells (RAW 264.7). Properties of the obtained composites were compared to the unmodified PLLA film as well as to the UV-laser irradiated PLLA. The activation of the PLLA surface by laser irradiation led to a distinct increase in cytotoxicity, while the treatment with SBF and the deposition of apatite ceramic had only a limited preventive effect on this harmful impact and depended on the cell type. Fibroblasts were found to have good tolerance for the irradiated and ceramic-covered PLLA, but macrophages seem to interact with the substrate leading to the release of cytotoxic products.

Download Full-text

UV Laser-Initiated Formation of Si3N4

MRS Proceedings ◽

10.1557/proc-17-129 ◽

1982 ◽

Vol 17 ◽

Cited By ~ 14

Author(s):

T. F. Deutsch ◽

D. J. Silversmith ◽

R. W. Mountain

Keyword(s):

Optical Properties ◽

Laser Radiation ◽

Vapor Deposition ◽

Chemical Vapor ◽

Uv Laser ◽

Pressure Chemical ◽

Excimer Laser Radiation ◽

Arf Excimer Laser ◽

193 Nm ◽

Substrate Temperatures

ABSTRACTSi3N4 films have been deposited on Si by using 193 nm ArF excimer laser radiation to initiate the reaction of SiH4 and NH3 at substrate temperatures between 200–600°C. Stoichiometric films having physical and optical properties comparable to those produced using low-pressure chemical vapor deposition (LPCVD) have been produced. The dielectric properties of the films are at present inferior to those of LPCVD material.

Download Full-text

UV Laser-Induced Metal Deposition on Semiconductors From Electroplating Solutions

MRS Proceedings ◽

10.1557/proc-75-173 ◽

1986 ◽

Vol 75 ◽

Cited By ~ 1

Author(s):

Joseph Zahavi ◽

Pehr E. Pehrsson

Keyword(s):

Laser Radiation ◽

Schottky Barrier ◽

Excimer Laser ◽

Pulse Energy ◽

Metal Deposition ◽

Uv Laser ◽

Sample Characterization ◽

Excimer Laser Radiation ◽

193 Nm

AbstractWe have demonstrated metal deposition on semiconductors immersed in electroplating solution by exposure to UV laser radiation. N-type β-SiC and Si in gold or Pd/Ni electroplating solutions were exposed to 20 ns pulses of 193 nm or 248 nm excimer laser radiation. The energy per pulse was 20–100 mJ. Au and Pd/Ni metallizations deposited in lines and circles on SiC showed leaky Schottky barrier I-V characteristics. The thickness increased with increasing pulse energy or number. Both masked and maskless deposition were demonstrated without apparent damage to the substrate. Details of the process, potential mechanisms, and sample characterization are discussed.

Download Full-text

Superhydrophobicity and Durability in Recyclable Polymers Coating

Sustainability ◽

10.3390/su13158244 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8244

Author(s):

Francesca Cirisano ◽

Michele Ferrari

Keyword(s):

Thermal Treatment ◽

Superhydrophobic Surface ◽

Low Cost ◽

Spray Coating ◽

Large Area ◽

Average Roughness ◽

Water Contact ◽

Alkaline Environments ◽

Fine Control ◽

Recycle And Reuse

Highly hydrophobic and superhydrophobic materials obtained from recycled polymers represent an interesting challenge to recycle and reuse advanced performance materials after their first life. In this article, we present a simple and low-cost method to fabricate a superhydrophobic surface by employing polytetrafluoroethylene (PTFE) powder in polystyrene (PS) dispersion. With respect to the literature, the superhydrophobic surface (SHS) was prepared by utilizing a spray- coating technique at room temperature, a glass substrate without any further modification or thermal treatment, and which can be applied onto a large area and on to any type of material with some degree of fine control over the wettability properties. The prepared surface showed superhydrophobic behavior with a water contact angle (CA) of 170°; furthermore, the coating was characterized with different techniques, such as a 3D confocal profilometer, to measure the average roughness of the coating, and scanning electron microscopy (SEM) to characterize the surface morphology. In addition, the durability of SH coating was investigated by a long-water impact test (raining test), thermal treatment at high temperature, an abrasion test, and in acidic and alkaline environments. The present study may suggest an easy and scalable method to produce SHS PS/PTFE films that may find implementation in various fields.

Download Full-text

Excimer Laser Interaction with Metals

MRS Proceedings ◽

10.1557/proc-285-145 ◽

1992 ◽

Vol 285 ◽

Cited By ~ 3

Author(s):

W.W. Duley ◽

G. Kinsman

Keyword(s):

Experimental Data ◽

Laser Radiation ◽

Excimer Laser ◽

Metal Surfaces ◽

Laser Pulses ◽

Radiative Properties ◽

Uv Laser ◽

Laser Interaction ◽

Excimer Laser Radiation

ABSTRACTExcimer laser radiation may be used to process metal surfaces in a variety of novel ways. The simplest of these involves the use of UV laser pulses for ablation. Ablation occurs as the result of both vaporization and hydrodynamical effects. Experimental data related to these processes will be discussed. In addition, it will be shown how specific irradiation regimes can yield metal surfaces with unique radiative properties.

Download Full-text

CARS and Fluorescent study of ignition of H2/O2 mixtures upon photodissociation of O2 molecular

MATEC Web of Conferences ◽

10.1051/matecconf/201820900010 ◽

2018 ◽

Vol 209 ◽

pp. 00010

Author(s):

Vitaly Kobtsev ◽

Sergey Kostritsa ◽

Dmitrii Kozlov ◽

Alexey Pelevkin ◽

Valery Smirnov ◽

...

Keyword(s):

Laser Radiation ◽

Combustion Chamber ◽

Test Bench ◽

Combustion Process ◽

Kinetic Mechanism ◽

Uv Laser ◽

Chain Reactions ◽

Ignition And Combustion ◽

193 Nm ◽

Experimental Test Bench

The research is devoted to gas mixtures ignition by UV laser radiation. The dissociation of O2 molecules by a pulse of excimer ArF laser radiation at 193-nm wavelength with formation of the chemically active oxygen atoms initiating chain reactions which cause ignition of H2/O2 mixture was employed. The experimental test bench was created with CARS and fluorescent techniques for experimental investigation of some peculiarities of mixture ignition and combustion caused by such photo-dissociation, at conditions typical for combustion chamber. Two-dimensional numerical modeling of combustion process in model combustion chamber, based on kinetic mechanism of H2 oxidation including atom O(1P) and radicals OH(A2Σ+), was performed.

Download Full-text

Ablation of poly(2-hydroxyethyl methacrylate) by 193-nm excimer laser radiation

Journal of Applied Polymer Science ◽

10.1002/app.1992.070440806 ◽

1992 ◽

Vol 44 (8) ◽

pp. 1355-1363 ◽

Cited By ~ 7

Author(s):

Traian V. Chirila ◽

Paul P. Van Saarloos

Keyword(s):

Laser Radiation ◽

Excimer Laser ◽

Hydroxyethyl Methacrylate ◽

Excimer Laser Radiation ◽

193 Nm

Download Full-text

Changes in optical interference coatings exposed to 193-nm excimer laser radiation

10.1117/12.344384 ◽

1999 ◽

Cited By ~ 4

Author(s):

Joerg Heber ◽

Roland Thielsch ◽

Holger Blaschke ◽

Norbert Kaiser ◽

Uwe Leinhos ◽

...

Keyword(s):

Laser Radiation ◽

Excimer Laser ◽

Optical Interference ◽

Excimer Laser Radiation ◽

193 Nm

Download Full-text

UV laser photochemistry and diborane at 193 nm: Quantum yield for BH3 production

Journal of Photochemistry ◽

10.1016/0047-2670(86)87002-2 ◽

1986 ◽

Vol 32 (2) ◽

pp. 139-142 ◽

Cited By ~ 9

Author(s):

Manfred P. Irion ◽

Karl-L. Kompa

Keyword(s):

Quantum Yield ◽

Uv Laser ◽

193 Nm

Download Full-text

Bonding PDMS Microfluidic Devices to PMMA and Glass Substrate Using Pulsed UV Laser Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.939.186 ◽

2014 ◽

Vol 939 ◽

pp. 186-193 ◽

Cited By ~ 1

Author(s):

Chih Chung Yang ◽

Wen Tse Hsiao ◽

Chien Kai Chung ◽

Kuo Cheng Huang

Keyword(s):

Adhesive Layer ◽

Polymeric Materials ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Oxygen Plasma Treatment ◽

Writing System ◽

Uv Laser ◽

Laser Writing ◽

Water Contact ◽

Sem Image

This study presents a new method for surface modification of polymeric materials by using pulsed UV laser welding technology. The bonding procedures including ablation treatment, Oxygen plasma treatment, adhesive layer bonding and cured by pulsed UV laser writing system was exhibited. The investigation of various parameters for UV laser writing system was performed and discussed by using water contact angle measurement. This technique has been successfully applied to bond dissimilar polymer substrates (polydimethylsiloxane (PDMS) to polymethylmethacrylate (PMMA)). The scanning electron microscopy (SEM) image reveals clearly that there was no clogging in the microchannel or deformation observed between PDMS and PMMA. The method was straightforward and the integrity of microfluidic features was successfully preserved after bonding.

Download Full-text