456
S. Arthanari et al.
regularly along the LIPSS surface and were random on the laser melted surface
[66]. The better cell viability and attachment of the melted surface were mainly
attributed to the lower hydrogen release, and pH raises due to the enhanced corrosion
resistance. Sub-micrometric surface structures produced by femtosecond laser on the
melted surface could provide a persistent mechanical stimulus for cells, resulting in a
controllable cell shape. Micrometer surface structures produced by picosecond laser
on the melted surface could affect the cell distribution due to the cell-repellent effect.
Laser surface patterning using the direct laser interference patterning (DLIP)
system produced periodic textures on AZ31 Mg alloy and the number of pulses
varied the average laser fluence [67]. The pattern produced using 64 number of
pulses exhibited good quality patterns and multiple passes increased the texture
quality by avoiding the material heat-up, which is often noticed for the long pulse
durations without any interruptions. The partial overlapping of the laser scanning
was also further confirmed that the periodic structure formation was stable for the
large processing areas and the interference angle played a major role in determining
the pattern periodicity.
3.2 Surface-Enhanced Raman Scattering (SERS) Responses
and Fluorescence Detection of Metal Surfaces
LIPSS has given an immense interest in recent days for various applications including
enhancement of Raman signal, photocatalysis, etc. Laser-induced surface structuring
possesses various advantages such as simple, precise, reproducible, and pollutionfree methods, in particular, this method can be easily applied to metallic materials that
have not been explored well. The LIPSS surfaces strongly affect the laser/material
interaction which could be used as an analytical tool to enhance the signals from the
biomolecules. Raman spectroscopy is one of the techniques which is widely used
to analyze various chemical compounds including biological components. In recent
days SERS is emerging as an analytical tool to identify biological molecules adhered
to the nano surfaces and enhances the signal intensity based upon the nature, size,
and composition of the surfaces [69, 70]. The SERS mainly uses plasmonic which
examines the interaction between the incident light and metallic nanostructures.
The optimization of surface nanostructures revealed a significant difference in the
signal corresponds to the adsorbed molecules, thus able to quantify them in biological
applications. Extensive studies are available on the preparation of metal nanoparticles
such as Ag and Au in various sizes and shapes using conventional techniques to
examine their SERS performances [71].
Laser surface texturing with hierarchical nano textures on metal surfaces which are
widely used in the biomedical applications to study the SERS response have not been
explored. Recently an attempt was made to fabricate the nanotextured surfaces on
Ti64 alloy using a femtosecond laser. The formation of a periodic structure (LIPSS)
with a periodicity of 600 nm and the nanoparticle with the diameter in the range
S. Arthanari et al.
regularly along the LIPSS surface and were random on the laser melted surface
[66]. The better cell viability and attachment of the melted surface were mainly
attributed to the lower hydrogen release, and pH raises due to the enhanced corrosion
resistance. Sub-micrometric surface structures produced by femtosecond laser on the
melted surface could provide a persistent mechanical stimulus for cells, resulting in a
controllable cell shape. Micrometer surface structures produced by picosecond laser
on the melted surface could affect the cell distribution due to the cell-repellent effect.
Laser surface patterning using the direct laser interference patterning (DLIP)
system produced periodic textures on AZ31 Mg alloy and the number of pulses
varied the average laser fluence [67]. The pattern produced using 64 number of
pulses exhibited good quality patterns and multiple passes increased the texture
quality by avoiding the material heat-up, which is often noticed for the long pulse
durations without any interruptions. The partial overlapping of the laser scanning
was also further confirmed that the periodic structure formation was stable for the
large processing areas and the interference angle played a major role in determining
the pattern periodicity.
3.2 Surface-Enhanced Raman Scattering (SERS) Responses
and Fluorescence Detection of Metal Surfaces
LIPSS has given an immense interest in recent days for various applications including
enhancement of Raman signal, photocatalysis, etc. Laser-induced surface structuring
possesses various advantages such as simple, precise, reproducible, and pollutionfree methods, in particular, this method can be easily applied to metallic materials that
have not been explored well. The LIPSS surfaces strongly affect the laser/material
interaction which could be used as an analytical tool to enhance the signals from the
biomolecules. Raman spectroscopy is one of the techniques which is widely used
to analyze various chemical compounds including biological components. In recent
days SERS is emerging as an analytical tool to identify biological molecules adhered
to the nano surfaces and enhances the signal intensity based upon the nature, size,
and composition of the surfaces [69, 70]. The SERS mainly uses plasmonic which
examines the interaction between the incident light and metallic nanostructures.
The optimization of surface nanostructures revealed a significant difference in the
signal corresponds to the adsorbed molecules, thus able to quantify them in biological
applications. Extensive studies are available on the preparation of metal nanoparticles
such as Ag and Au in various sizes and shapes using conventional techniques to
examine their SERS performances [71].
Laser surface texturing with hierarchical nano textures on metal surfaces which are
widely used in the biomedical applications to study the SERS response have not been
explored. Recently an attempt was made to fabricate the nanotextured surfaces on
Ti64 alloy using a femtosecond laser. The formation of a periodic structure (LIPSS)
with a periodicity of 600 nm and the nanoparticle with the diameter in the range