scholarly journals Controlled pDNA Release in Gemini Cationic Lipoplexes by Femtosecond Laser Irradiation of Gold Nanostars

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1498
Author(s):  
Natalia Sánchez-Arribas ◽  
Pablo Díaz-Núñez ◽  
José Osío Barcina ◽  
Emilio Aicart ◽  
Elena Junquera ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Near Infrared ◽  
Irradiation Time ◽  
Nir Spectroscopy ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Cationic Lipids ◽  
Femtosecond Laser Irradiation ◽  
Gold Nanostars

The design of nanovectors able to overcome biological barriers is one of the main challenges in biomedicine. Gemini cationic lipids are considered potential candidates for gene therapy due to their high biocompatibility and capacity to condense nucleic acids safely in the form of lipoplexes. However, this approach presents difficulties regarding genetic unpacking and, therefore, control over this process becomes crucial to ensure successful transfection. In this work, gemini cationic lipoplexes were prepared in the presence of plasmonic gold nanostars (AuNSs) to afford a nanovector that efficiently releases plasmid DNA (pDNA) upon irradiation with near-infrared femtosecond laser pulses. A critical AuNSs concentration of 50 pM and optimized laser power density of 400 mW led to successful pDNA release, whose efficiency could be further improved by increasing the irradiation time. Agarose gel electrophoresis was used to confirm pDNA release. UV-Vis-NIR spectroscopy and transmission electron microscopy studies were performed to monitor changes in the morphology of the AuNSs and lipoplexes after irradiation. From a physicochemical point of view, this study demonstrates that the use of AuNSs combined with gemini cationic lipoplexes allows control over pDNA release under ultrafast laser irradiation.

scholarly journals Processing of Single-Walled Carbon Nanotubes with Femtosecond Laser Pulses

2019 ◽  
Vol 9 (19) ◽  
pp. 4022 ◽  
Author(s):  
Zeyad Almutairi ◽  
Kaleem Ahmad ◽  
Mosaad Alanazi ◽  
Abdulaziz Alhazaa
Keyword(s):  
Carbon Nanotubes ◽  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Cost Effective ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Femtosecond Laser Irradiation ◽  
Single Wall Carbon Nanotubes ◽  
Glass Substrates ◽  
Focus Plane

There are continued efforts to process and join single wall carbon nanotubes (SWCNTs) in order to exploit their exceptional functional properties for real-world applications. In this work, we report experimental observations of femtosecond laser irradiation on SWCNTs, in order to process and join them through an efficient and cost-effective technique. The nanotubes were deagglomerated in ethanol by an ultrasonicator and thin slurries of SWCNTs were spread evenly on glass substrates. A laser micromachining workstation for laboratory FemtoLAB (workshop of photonics) has been employed to irradiate the different SWCNTs film samples. The effect of laser parameters, such as pulse wavelength, laser power, etc., were systematically tuned to see the possibility of joining the SWCNTs ropes. Several experiments have been performed to optimize the parameters on different samples of SWCNTs. In general, the nanotubes were mostly damaged by the infrared (1st harmonics femtosecond laser) irradiation on the focal plane. However, the less damaging effect was observed for second harmonics (green wavelength) irradiation. The results suggest some joining of nanotubes along the sides of the focus plane, as well as on the center at the brink of nanotubes. The joining is considered to be established within the region of the high field intensity of the exposed femtosecond laser beam.

scholarly journals Regulating disordered plasmonic nanoparticles into polarization sensitive metasurfaces

Nanophotonics ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Shulei Li ◽  
Mingcheng Panmai ◽  
Shaolong Tie ◽  
Yi Xu ◽  
Jin Xiang ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Spatial Resolution ◽  
Metallic Nanoparticles ◽  
Near Infrared ◽  
Optical Memory ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Optical Diffraction ◽  
Plasmonic Nanoparticles ◽  
Direct Laser

Abstract Metasurfaces composed of regularly arranged and deliberately oriented metallic nanoparticles can be employed to manipulate the amplitude, phase and polarization of an incident electromagnetic wave. The metasurfaces operating in the visible to near infrared spectral range rely on the modern fabrication technologies which offer a spatial resolution beyond the optical diffraction limit. Although direct laser writing is an alternative to the fabrication of nanostructures, the achievement of regular nanostructures with deep-subwavelength periods by using this method remains a big challenge. Here, we proposed and demonstrated a novel strategy for regulating disordered plasmonic nanoparticles into nanogratings with deep-subwavelength periods and reshaped nanoparticles by using femtosecond laser pulses. The orientations of the nanogratings depend strongly on the polarization of the femtosecond laser light. Such nanogratings exhibit reflection and polarization control over the reflected light, enabling the realization of polarization sensitive optical memory and color display with high spatial resolution and good chromacity.

scholarly journals Sacrificial-layer free transfer of mammalian cells using near infrared femtosecond laser pulses

PLoS ONE ◽  
2018 ◽  
Vol 13 (5) ◽  
pp. e0195479 ◽  
Author(s):  
Jun Zhang ◽  
Bastian Hartmann ◽  
Julian Siegel ◽  
Gabriele Marchi ◽  
Hauke Clausen-Schaumann ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Mammalian Cells ◽  
Near Infrared ◽  
Sacrificial Layer ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses

scholarly journals Graphene Oxide-Based Silico-Phosphate Composite Films for Optical Limiting of Ultrashort Near-Infrared Laser Pulses

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1638 ◽  
Author(s):  
Adrian Petris ◽  
Ileana Cristina Vasiliu ◽  
Petronela Gheorghe ◽  
Ana Maria Iordache ◽  
Laura Ionel ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Femtosecond Laser ◽  
Near Infrared ◽  
Substrate Surface ◽  
Sol Gel ◽  
Composite Films ◽  
Laser Pulses ◽  
Optical Limiting ◽  
Femtosecond Laser Pulses ◽  
Glassy Matrix

The development of graphene-based materials for optical limiting functionality is an active field of research. Optical limiting for femtosecond laser pulses in the infrared-B (IR-B) (1.4–3 μm) spectral domain has been investigated to a lesser extent than that for nanosecond, picosecond and femtosecond laser pulses at wavelengths up to 1.1 μm. Novel nonlinear optical materials, glassy graphene oxide (GO)-based silico-phosphate composites, were prepared, for the first time to our knowledge, by a convenient and low cost sol-gel method, as described in the paper, using tetraethyl orthosilicate (TEOS), H3PO4 and GO/reduced GO (rGO) as precursors. The characterisation of the GO/rGO silico-phosphate composite films was performed by spectroscopy (Fourier-transform infrared (FTIR), Ultraviolet–Visible-Near Infrared (UV-VIS-NIR) and Raman) and microscopy (atomic force microscopy (AFM) and scanning electron microscopy (SEM)) techniques. H3PO4 was found to reduce the rGO dispersed in the precursor’s solution with the formation of vertically agglomerated rGO sheets, uniformly distributed on the substrate surface. The capability of these novel graphene oxide-based materials for the optical limiting of femtosecond laser pulses at 1550 nm wavelength was demonstrated by intensity-scan experiments. The GO or rGO presence in the film, their concentrations, the composite films glassy matrix, and the film substrate influence the optical limiting performance of these novel materials and are discussed accordingly.

In vivo animal follow-up studies on intrastromal surgery with near-infrared nanojoule femtosecond laser pulses

2005 ◽  
Author(s):  
Baogui Wang ◽  
Iris Riemann ◽  
Karl-Juergen Halbhuber ◽  
Harald Schubert ◽  
Sigrun Kirste ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Near Infrared ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Follow Up Studies

scholarly journals Interaction of near-infrared femtosecond laser pulses with biological materials in water

2014 ◽  
Vol 53 (5) ◽  
pp. 051510
Author(s):  
Sanjay Varma ◽  
Nathan Hagan ◽  
Miquel Antoine ◽  
Joseph Miragliotta ◽  
Plamen Demirev
Keyword(s):  
Femtosecond Laser ◽  
Near Infrared ◽  
Laser Pulses ◽  
Biological Materials ◽  
Femtosecond Laser Pulses
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