|
1
|
Xiong Z, Poudel A, Narkar AR, Zhang Z, Kunwar P, Henderson JH, Soman P. Femtosecond Laser Densification of Hydrogels to Generate Customized Volume Diffractive Gratings. ACS APPLIED MATERIALS & INTERFACES 2022; 14:29377-29385. [PMID: 35696613 PMCID: PMC9247983 DOI: 10.1021/acsami.2c04589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Inspired by nature's ability to shape soft biological materials to exhibit a range of optical functionalities, we report femtosecond (fs) laser-induced densification as a new method to generate volume or subsurface diffractive gratings within ordinary hydrogel materials. We characterize the processing range in terms of fs laser power, speed, and penetration depths for achieving densification within poly(ethylene glycol) diacrylate (PEGDA) hydrogel and characterize the associated change in local refractive index (RI). The RI change facilitates the fabrication of custom volume gratings (parallel line, grid, square, and ring gratings) within PEGDA. To demonstrate this method's broad applicability, fs laser densification was used to generate line gratings within the phenylboronic acid (PBA) hydrogel, which is known to be responsive to changes in pH. In the future, this technique can be used to convert ordinary hydrogels into multicomponent biophotonic systems.
Collapse
Affiliation(s)
- Zheng Xiong
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Arun Poudel
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Ameya R. Narkar
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Zhe Zhang
- BioInspired
Syracuse: Institute for Material and Living Systems, Syracuse University, Syracuse, New York 13244, United States
| | - Puskal Kunwar
- BioInspired
Syracuse: Institute for Material and Living Systems, Syracuse University, Syracuse, New York 13244, United States
| | - James H. Henderson
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Pranav Soman
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
- Email
| |
Collapse
|
|
2
|
Stankova N, Nikolov A, Iordanova E, Yankov G, Nedyalkov N, Atanasov P, Tatchev D, Valova E, Kolev K, Armyanov S, Karashanova D, Fukata N. New Approach toward Laser-Assisted Modification of Biocompatible Polymers Relevant to Neural Interfacing Technologies. Polymers (Basel) 2021; 13:polym13173004. [PMID: 34503043 PMCID: PMC8433805 DOI: 10.3390/polym13173004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/28/2021] [Accepted: 09/01/2021] [Indexed: 11/16/2022] Open
Abstract
We report on a new approach toward a laser-assisted modification of biocompatible polydimethylsiloxane (PDMS) elastomers relevant to the fabrication of stretchable multielectrode arrays (MEAs) devices for neural interfacing technologies. These applications require high-density electrode packaging to provide a high-resolution integrating system for neural stimulation and/or recording. Medical grade PDMS elastomers are highly flexible with low Young’s modulus < 1 MPa, which are similar to soft tissue (nerve, brain, muscles) among the other known biopolymers, and can easily adjust to the soft tissue curvatures. This property ensures tight contact between the electrodes and tissue and promotes intensive development of PDMS-based MEAs interfacing devices in the basic neuroscience, neural prosthetics, and hybrid bionic systems, connecting the human nervous system with electronic or robotic prostheses for restoring and treating neurological diseases. By using the UV harmonics 266 and 355 nm of Nd:YAG laser medical grade PDMS elastomer is modified by ns-laser ablation in water. A new approach of processing is proposed to (i) activate the surface and to obtain tracks with (ii) symmetric U-shaped profiles and (iii) homogeneous microstructure This technology provides miniaturization of the device and successful functionalization by electroless metallization of the tracks with platinum (Pt) without preliminary sensitization by tin (Sn) and chemical activation by palladium (Pd). As a result, platinum black layers with a cauliflower-like structure with low values of sheet resistance between 1 and 8 Ω/sq are obtained.
Collapse
Affiliation(s)
- Nadya Stankova
- Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shousse Blvd., 1784 Sofia, Bulgaria; (A.N.); (N.N.); (P.A.)
- Correspondence:
| | - Anastas Nikolov
- Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shousse Blvd., 1784 Sofia, Bulgaria; (A.N.); (N.N.); (P.A.)
| | - Ekaterina Iordanova
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shousse Blvd., 1784 Sofia, Bulgaria; (E.I.); (G.Y.)
| | - Georgi Yankov
- Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shousse Blvd., 1784 Sofia, Bulgaria; (E.I.); (G.Y.)
| | - Nikolay Nedyalkov
- Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shousse Blvd., 1784 Sofia, Bulgaria; (A.N.); (N.N.); (P.A.)
| | - Petar Atanasov
- Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shousse Blvd., 1784 Sofia, Bulgaria; (A.N.); (N.N.); (P.A.)
| | - Dragomir Tatchev
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str. Bld.11, 1113 Sofia, Bulgaria; (D.T.); (E.V.); (K.K.); (S.A.)
| | - Eugenia Valova
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str. Bld.11, 1113 Sofia, Bulgaria; (D.T.); (E.V.); (K.K.); (S.A.)
| | - Konstantin Kolev
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str. Bld.11, 1113 Sofia, Bulgaria; (D.T.); (E.V.); (K.K.); (S.A.)
| | - Stephan Armyanov
- Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str. Bld.11, 1113 Sofia, Bulgaria; (D.T.); (E.V.); (K.K.); (S.A.)
| | - Daniela Karashanova
- Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, G. Bonchev Street, Bl. 109, 1113 Sofia, Bulgaria;
| | - Naoki Fukata
- International Center for Materials for Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1Namiki, Tsikuba 305-0044, Japan;
| |
Collapse
|