Evaluation of 3D structures fabricated with two-photon-photopolymerization by using FTIR spectroscopy

2011 ◽  
Vol 110 (6) ◽  
pp. 064911 ◽  
Author(s):  
Klaus Cicha ◽  
Zhiquan Li ◽  
Klaus Stadlmann ◽  
Aleksandr Ovsianikov ◽  
Ruth Markut-Kohl ◽  
...  
Keyword(s):  
Ftir Spectroscopy ◽  
3D Structures ◽  
Two Photon

scholarly journals Refractive index matched polymeric and preceramic resins for height-scalable two-photon lithography

RSC Advances ◽  
2021 ◽  
Vol 11 (37) ◽  
pp. 22633-22639
Author(s):  
Magi Mettry ◽  
Matthew A. Worthington ◽  
Brian Au ◽  
Jean-Baptiste Forien ◽  
Swetha Chandrasekaran ◽  
...  
Keyword(s):  
Refractive Index ◽  
3D Structures ◽  
Two Photon

Studying the effect of resin RI on print fidelity. Chemically modifying RI resins to demonstrate 3D structures print without height limitation resulting on ceramic and nonceramic print as tall as 2.5 mm with sub-micron features.

3D-structuring of Optical Waveguides with Two Photon Polymerization

2009 ◽  
Vol 1179 ◽  
Author(s):  
Robert Infuehr ◽  
Jurgen Stampfl ◽  
Stefan Krivec ◽  
Robert Liska ◽  
Helga Lichtenegger ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Waveguides ◽  
Elevated Temperatures ◽  
Sol Gel ◽  
Matrix Material ◽  
Optical Data Storage ◽  
Optical Data ◽  
Laser Exposure ◽  
3D Structures ◽  
Two Photon

AbstractTwo photon photopolymerization (2PP) is a new and modern method in solid freeform fabrication. 2PP allows the fabrication of sub-micron structures from a photopolymerizable resin. By the use of near-infrared (NIR) lasers it is possible to produce 3D structures with a spatial feature resolution as good as 200 nm. This technique can be used in polymer-based photonic and micro-electromechanical systems (MEMS), for 3D optical data storage or for the inscription of optical waveguides based on a local refractive index change upon laser exposure. Since the 2PP only takes place inside the focus of the laser beam, complex 3D-structures can be in-scri-bed into a suitable matrix material.In the presented work, 2PP is used to write optical waveguides into a prefabricated mechanically flexible polydimethylsiloxane matrix. The waveguides were structured by selectively irradiating a polymer network, which was swollen by a monomer mixture. The monomer was polymerized by two photon photopolymerization and the uncured monomer was removed by evaporation at elevated temperatures. This treatment led to a local change in refractive index in the order of Δn = 0.02, which was significantly above the industrial requirement of Δn = 0.003. The measured optical losses were around 2.3dB/cm. Since all unreacted monomers were removed by eva-po-ration, the final waveguide was stable up to temperatures of more than 200°C.In a second approach highly porous sol-gel materials (based on tetramethoxysilane (TMOS) as precursor and the surfactant cetylpyridinium chloride monohydrate as structural temp-late) were utilized as matrix materials. The precursor was organically modified with poly(ethylene glycol) spacers in order to increase the toughness and thus facilitate the fabrication of transparent porous monoliths and flexible films. The pores of the sol-gel-derived matrix were filled with acrylate-based monomers of high refractive index and after selective irradiation using 2PP waveguides (Δn = 0.015) could be written into the material.

scholarly journals Collagen/Chitosan Functionalization of Complex 3D Structures Fabricated by Laser Direct Writing via Two-Photon Polymerization for Enhanced Osteogenesis

2020 ◽  
Vol 21 (17) ◽  
pp. 6426
Author(s):  
Irina Alexandra Păun ◽  
Cosmin Cătălin Mustăciosu ◽  
Roxana Cristina Popescu ◽  
Bogdan Ştefăniţă Călin ◽  
Mona Mihăilescu
Keyword(s):  
Bone Substitutes ◽  
Staining Intensity ◽  
Dip Coating ◽  
Direct Writing ◽  
Laser Direct Writing ◽  
Alizarin Red ◽  
Biological Assays ◽  
3D Structures ◽  
Two Photon ◽  
Osteogenic Effect

The fabrication of 3D microstructures is under continuous development for engineering bone substitutes. Collagen/chitosan (Col/CT) blends emerge as biomaterials that meet the mechanical and biological requirements associated with bone tissue. In this work, we optimize the osteogenic effect of 3D microstructures by their functionalization with Col/CT blends with different blending ratios. The structures were fabricated by laser direct writing via two-photons polymerization of IP-L780 photopolymer. They comprised of hexagonal and ellipsoidal units 80 µm in length, 40 µm in width and 14 µm height, separated by 20 µm pillars. Structures’ functionalization was achieved via dip coating in Col/CT blends with specific blending ratios. The osteogenic role of Col/CT functionalization of the 3D structures was confirmed by biological assays concerning the expression of alkaline phosphatase (ALP) and osteocalcin secretion as osteogenic markers and Alizarin Red (AR) as dye for mineral deposits in osteoblast-like cells seeded on the structures. The structures having ellipsoidal units showed the best results, but the trends were similar for both ellipsoidal and hexagonal units. The strongest osteogenic effect was obtained for Col/CT blending ratio of 20/80, as demonstrated by the highest ALP activity, osteocalcin secretion and AR staining intensity in the seeded cells compared to all the other samples.

scholarly journals Process Development for Additive Manufacturing of Alumina Toughened Zirconia for 3D Structures by Means of Two-Photon Absorption Technique

Ceramics ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 224-239
Author(s):  
Gerhard Hildebrand ◽  
Johanna C. Sänger ◽  
Uwe Schirmer ◽  
Willi Mantei ◽  
Yannick Dupuis ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
3D Printing ◽  
Single Photon ◽  
High Accuracy ◽  
Photon Absorption ◽  
Solid Loading ◽  
Oxide Ceramic ◽  
3D Structures ◽  
Two Photon Absorption ◽  
Two Photon

Additive manufacturing is well established for plastics and metals, and it gets more and more implemented in a variety of industrial processes. Beside these well-established material platforms, additive manufacturing processes are highly interesting for ceramics, especially regarding resource conservation and for the production of complex three-dimensional shapes and structures with specific feature sizes in the µm and mm range with high accuracy. The usage of ceramics in 3D printing is, however, just at the beginning of a technical implementation in a continuously and fast rising field of research and development. The flexible fabrication of highly complex and precise 3D structures by means of light-induced photopolymerization that are difficult to realize using traditional ceramic fabrication methods such as casting and machining is of high importance. Generally, slurry-based ceramic 3D printing technologies involve liquid or semi-liquid polymeric systems dispersed with ceramic particles as feedstock (inks or pastes), depending on the solid loading and viscosity of the system. This paper includes all types of photo-curable polymer-ceramic-mixtures (feedstock), while demonstrating our own work on 3D printed alumina toughened zirconia based ceramic slurries with light induced polymerization on the basis of two-photon absorption (TPA) for the first time. As a proven exemplary on cuboids with varying edge length and double pyramids in the µm-range we state that real 3D micro-stereolithographic fabrication of ceramic products will be generally possible in the near future by means of TPA. This technology enables the fabrication of 3D structures with high accuracy in comparison to ceramic technologies that apply single-photon excitation. In sum, our work is intended to contribute to the fundamental development of this technology for the representation of oxide-ceramic components (proof-of-principle) and helps to exploit the high potential of additive processes in the field of bio-ceramics in the medium to long-term future.

scholarly journals Two-photon polymerization of hydrogels – versatile solutions to fabricate well-defined 3D structures

RSC Advances ◽  
2014 ◽  
Vol 4 (85) ◽  
pp. 45504-45516 ◽  
Author(s):  
Adina I. Ciuciu ◽  
Piotr J. Cywiński
Keyword(s):  
3D Structures ◽  
Two Photon ◽  
Two Photon Polymerization

Solid-state synthesis of unsaturated chitosan derivatives to design 3D structures through two-photon-induced polymerization

2015 ◽  
Vol 25 (4) ◽  
pp. 280-282 ◽  
Author(s):  
Tatiana A. Akopova ◽  
Petr S. Timashev ◽  
Tatiana S. Demina ◽  
Kseniya N. Bardakova ◽  
Nikita V. Minaev ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Synthesis ◽  
Chitosan Derivatives ◽  
3D Structures ◽  
Two Photon

Two-photon excitation microscopy in cellular biophysics

1995 ◽  
Vol 53 ◽  
pp. 62-63
Author(s):  
David W. Piston ◽  
Brian D. Bennett ◽  
Robert G. Summers
Keyword(s):  
Confocal Microscopy ◽  
Laser Beam ◽  
Duty Cycle ◽  
Excited Electronic State ◽  
Input Power ◽  
Two Photon ◽  
Simultaneous Absorption ◽  
Photon Excitation ◽  
Very High ◽  
Two Photon Excitation

Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10-5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

Two-photon excitation fluorescence microscopy in living systems

1993 ◽  
Vol 51 ◽  
pp. 154-155 ◽  
Author(s):  
David W. Piston
Keyword(s):  
Confocal Microscopy ◽  
Fluorescence Microscopy ◽  
Singlet State ◽  
Excited Electronic State ◽  
Input Power ◽  
Two Photon ◽  
Simultaneous Absorption ◽  
Photon Excitation ◽  
Very High ◽  
Two Photon Excitation

Two-photon excitation fluorescence microscopy provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging. Two-photon excitation arises from the simultaneous absorption of two photons in a single quantitized event whose probability is proportional to the square of the instantaneous intensity. For example, two red photons can cause the transition to an excited electronic state normally reached by absorption in the ultraviolet. In our fluorescence experiments, the final excited state is the same singlet state that is populated during a conventional fluorescence experiment. Thus, the fluorophore exhibits the same emission properties (e.g. wavelength shifts, environmental sensitivity) used in typical biological microscopy studies. In practice, two-photon excitation is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10−5 maintains the average input power on the order of 10 mW, only slightly greater than the power normally used in confocal microscopy.

Sign in / Sign up

Export Citation Format

Share Document