CHARACTERIZING THREE-DIMENSIONAL MICROSTRUCTURE OF COLLAGEN/CHITOSAN SCAFFOLDS USING MULTIPHOTON MICROSCOPE

In this work, we used multiphoton microscopic system for characterizing three-dimensional microstructure of collagen/chitosan polymeric scaffolds in a noninvasive fashion. Nonlinear optical signals including multiphoton autofluorescence (MAF) and second harmonic generation (SHG) derived from collagen/chitosan scaffolds were collected and analyzed. The three-dimensional porous microstructures of collagen/chitosan scaffolds were visualized by co-localized and evenly distributed MAF and SHG signals. The distribution of collagen and chitosan compositions within miscible collagen/chitosan blends cannot be either localized or differentiated simply using these nonlinear optical signals. However, the intensity of MAF signals in scaffolds was found to be markedly decreased in correlation to the supplementation of chitosan within blends, regardless of collagen/chitosan weight ratios. It therefore implied that the MAF-generating molecules within collagen being altered in miscible collagen/chitosan blends. And the SHG signals also decreased significantly in collagen/chitosan scaffolds with the supplementation of chitosan, regardless of different weight ratios. This finding supported the hypothesis regarding the miscibility of collagen/chitosan blends that triple helix structure of collagen, a proven SHG-generating microstructure, was altered in miscible collagen/chitosan blends. In conclusion, our work demonstrated that multiphoton imaging modality can be versatile for investigating three-dimensional microstructure of miscible polymeric scaffolds in a minimal invasive fashion, and may potentially be applicable in the field of tissue engineering.

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Na4Yb(CO3)3F: A New UV Nonlinear Optical Material with a Large Second Harmonic Generation Response

Crystals ◽

10.3390/cryst8100381 ◽

2018 ◽

Vol 8 (10) ◽

pp. 381

Author(s):

Qiaoling Chen ◽

Min Luo ◽

Chensheng Lin

Keyword(s):

Second Harmonic Generation ◽

Harmonic Generation ◽

Nonlinear Optical ◽

Diffuse Reflectance ◽

Second Harmonic ◽

Three Dimensional ◽

One Dimensional ◽

Nonlinear Optical Crystals ◽

3D Network ◽

3D Framework

A new nonlinear optical crystals fluoride carbonate, Na4Yb(CO3)3F, has been synthesized by mild hydrothermal method. The Na4Yb(CO3)3F crystallizes in the noncentrosymmetric space group Cc (no. 9) with the lattice parameters a = 8.018(3), b = 15.929(5), c = 13.950(5) Å and β = 101.425(6)°. The compound Na4Yb(CO3)3F has a high density of [CO3] groups. The structure can be described as one-dimensional [Na5Yb(CO3)2F2] chains connected by [CO3] groups, forming an intricate three-dimensional (3D) framework. Other Na+ and Yb3+ cations are located in the cavities of 3D network. The powder second harmonic generation (SHG) measurement shows that Na4Yb(CO3)3F features a large SHG response, about 4.3 times that of KH2PO4 (KDP), and is a phase-matchable material. In addition, its UV-Vis-NIR diffuse reflectance spectral data indicate that Na4Yb(CO3)3F has a large optical gap about 4.72 eV, which corresponds to the UV cut-off edge of 263 nm.

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(Second) Harmonic Disharmony: Nonlinear Microscopy Shines New Light on the Pathology of Atherosclerosis

Microscopy and Microanalysis ◽

10.1017/s1431927616000842 ◽

2016 ◽

Vol 22 (3) ◽

pp. 589-598 ◽

Cited By ~ 4

Author(s):

Shana R. Watson ◽

Susan M. Lessner

Keyword(s):

Raman Scattering ◽

Stimulated Raman Scattering ◽

Second Harmonic ◽

Imaging Modality ◽

Pathological Condition ◽

Three Dimensional ◽

Atherosclerotic Lesion ◽

Optical Microscope ◽

Deep Penetration ◽

Control Versus

AbstractThere has been increasing interest in second harmonic generation (SHG) imaging approaches for the investigation of atherosclerosis due to the deep penetration and three-dimensional sectioning capabilities of the nonlinear optical microscope. Atherosclerosis involves remodeling or alteration of the collagenous framework in affected vessels. The disease is often characterized by excessive collagen deposition and altered collagen organization. SHG has the capability to accurately characterize collagen structure, which is an essential component in understanding atherosclerotic lesion development and progression. As a structure-based imaging modality, SHG is most impactful in atherosclerosis evaluation in conjunction with other, chemically specific nonlinear optics (NLO) techniques to identify additional components of the lesion. These include the use of coherent anti-Stokes Raman scattering and two-photon excitation fluorescence for studying atherosclerosis burden, and application of stimulated Raman scattering to image cholesterol crystals. However, very few NLO studies have attempted to quantitate differences in control versus atherosclerotic states or to correlate the application to clinical situations. This review highlights the potential of SHG imaging to directly and indirectly describe atherosclerosis as a pathological condition.

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NONLINEAR SPECTRAL IMAGING OF ELASTIC CARTILAGE IN RABBIT EARS

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545813500247 ◽

2013 ◽

Vol 06 (03) ◽

pp. 1350024 ◽

Cited By ~ 2

Author(s):

JING CHEN ◽

CHUNGEN GUO ◽

HONGSHENG LI ◽

XIAOQIN ZHU ◽

SHUYUAN XIONG ◽

...

Keyword(s):

Nonlinear Optical ◽

Second Harmonic ◽

Three Dimensional ◽

Emission Spectra ◽

Cartilage Tissue ◽

Dimensional Structure ◽

Attractive Potential ◽

Elastic Fibers ◽

Cell Nuclei ◽

Elastic Cartilage

Elastic cartilage in the rabbit external ear is an important animal model with attractive potential value for researching the physiological and pathological states of cartilages especially during wound healing. In this work, nonlinear optical microscopy based on two-photon excited fluorescence and second harmonic generation were employed for imaging and quantifying the intact elastic cartilage. The morphology and distribution of main components in elastic cartilage including cartilage cells, collagen and elastic fibers were clearly observed from the high-resolution two-dimensional nonlinear optical images. The areas of cell nuclei, a parameter related to the pathological changes of normal or abnormal elastic cartilage, can be easily quantified. Moreover, the three-dimensional structure of chondrocytes and matrix were displayed by constructing three-dimensional image of cartilage tissue. At last, the emission spectra from cartilage were obtained and analyzed. We found that the different ratio of collagen over elastic fibers can be used to locate the observed position in the elastic cartilage. The redox ratio based on the ratio of nicotinamide adenine dinucleotide (NADH) over flavin adenine dinucleotide (FAD) fluorescence can also be calculated to analyze the metabolic state of chondrocytes in different regions. Our results demonstrated that this technique has the potential to provide more accurate and comprehensive information for the physiological states of elastic cartilage.

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Second Harmonic Generation of Bacteriorhodopsin and its Application for Three-Dimensional Optical Memory

MRS Proceedings ◽

10.1557/proc-330-263 ◽

1993 ◽

Vol 330 ◽

Author(s):

Zhongping Chen ◽

A. Lewis ◽

J. Kumart ◽

S. Tripathy ◽

K. Marxt ◽

...

Keyword(s):

Optical Properties ◽

Second Harmonic Generation ◽

Harmonic Generation ◽

Nonlinear Optical ◽

Second Harmonic ◽

Three Dimensional ◽

Optical Memory ◽

Nondestructive Method ◽

Reading And Writing ◽

Fast Speed

ABSTRACTA novel three-dimensional optical memory system based on a light transducing protein, bacteriorhodopsin, is investigated. The system uses the nonlinear optical properties of bacteriorhodopsin to accomplish reading and writing operations. A nondestructive method of reading information in three-dimensional optical memory that uses second harmonic generation is demonstrated. This method has the advantage of fast speed, is nondestructive, and has the potential for parallel access.

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A new phase-matchable nonlinear optical silicate: Rb2ZnSi3O8

Journal of Materials Chemistry C ◽

10.1039/c7tc03000b ◽

2017 ◽

Vol 5 (42) ◽

pp. 11025-11029 ◽

Cited By ~ 9

Author(s):

Bingqing Zhao ◽

Yi Yang ◽

Sangen Zhao ◽

Yaoguo Shen ◽

Xianfeng Li ◽

...

Keyword(s):

Second Harmonic Generation ◽

Harmonic Generation ◽

Nonlinear Optical ◽

Second Harmonic ◽

Three Dimensional ◽

Dimensional Structure ◽

Three Dimensional Structure ◽

New Phase

A new asymmetric silicate Rb2ZnSi3O8with a three-dimensional structure shows phase-matchability and enhanced second-harmonic generation as compared with α-SiO2.

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Synthesis and nonlinear optical properties of novel T-type polyurethanes with high thermal stability of second harmonic generation

Synthetic Metals ◽

10.1016/j.synthmet.2004.09.032 ◽

2005 ◽

Vol 148 (2) ◽

pp. 161-168 ◽

Cited By ~ 10

Author(s):

Ju-Yeon Lee ◽

Han-Bae Bang ◽

Chang Suk Baek

Keyword(s):

Thermal Stability ◽

Optical Properties ◽

Second Harmonic Generation ◽

Harmonic Generation ◽

Nonlinear Optical ◽

Second Harmonic ◽

High Thermal Stability ◽

Nonlinear Optical Properties ◽

Thermal Stability Of

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Is Dialdehyde Chitosan a Good Substance to Modify Physicochemical Properties of Biopolymeric Materials?

International Journal of Molecular Sciences ◽

10.3390/ijms22073391 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3391

Author(s):

Sylwia Grabska-Zielińska ◽

Alina Sionkowska ◽

Ewa Olewnik-Kruszkowska ◽

Katarzyna Reczyńska ◽

Elżbieta Pamuła

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

Physicochemical Properties ◽

Silk Fibroin ◽

Three Dimensional ◽

Microscopy Imaging ◽

Maximum Deformation ◽

One Step ◽

Chitosan Blends ◽

Fourier Transfer Infrared Spectroscopy

The aim of this work was to compare physicochemical properties of three dimensional scaffolds based on silk fibroin, collagen and chitosan blends, cross-linked with dialdehyde starch (DAS) and dialdehyde chitosan (DAC). DAS was commercially available, while DAC was obtained by one-step synthesis. Structure and physicochemical properties of the materials were characterized using Fourier transfer infrared spectroscopy with attenuated total reflectance device (FTIR-ATR), swelling behavior and water content measurements, porosity and density observations, scanning electron microscopy imaging (SEM), mechanical properties evaluation and thermogravimetric analysis. Metabolic activity with AlamarBlue assay and live/dead fluorescence staining were performed to evaluate the cytocompatibility of the obtained materials with MG-63 osteoblast-like cells. The results showed that the properties of the scaffolds based on silk fibroin, collagen and chitosan can be modified by chemical cross-linking with DAS and DAC. It was found that DAS and DAC have different influence on the properties of biopolymeric scaffolds. Materials cross-linked with DAS were characterized by higher swelling ability (~4000% for DAS cross-linked materials; ~2500% for DAC cross-linked materials), they had lower density (Coll/CTS/30SF scaffold cross-linked with DAS: 21.8 ± 2.4 g/cm3; cross-linked with DAC: 14.6 ± 0.7 g/cm3) and lower mechanical properties (maximum deformation for DAC cross-linked scaffolds was about 69%; for DAS cross-linked scaffolds it was in the range of 12.67 ± 1.51% and 19.83 ± 1.30%) in comparison to materials cross-linked with DAC. Additionally, scaffolds cross-linked with DAS exhibited higher biocompatibility than those cross-linked with DAC. However, the obtained results showed that both types of scaffolds can provide the support required in regenerative medicine and tissue engineering. The scaffolds presented in the present work can be potentially used in bone tissue engineering to facilitate healing of small bone defects.

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