Minimally Invasive Infrared Imaging of Caenorhabditis elegans Enabled by Reversible Chemical Immobilization and Second-Derivative Spectral Mapping
4 affiliations
- 1Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
- 2Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
- 3The OMU Advanced Research Institute for Natural Science and Technology, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
- 4OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan
Abstract
The nematode Caenorhabditis elegans is a widely used model organism, yet its infrared (IR) spectroscopic characterization has been limited by motion and strong water absorption in the mid-infrared region. Here, we establish a minimally invasive mid-infrared imaging method for C. elegans by combining reversible immobilization with sodium azide (NaN3) and measurements in deuterium oxide (D2O). NaN3 effectively suppressed locomotion without inducing irreversible physiological damage, enabling high-quality acquisition of IR images. Mid-IR hyperspectral data were analyzed to extract lipid- and protein-specific bands for each pixel, followed by second-derivative analysis of the Amide I band to resolve protein secondary-structure components. This allowed decomposition of α-helical (1658 cm–1) and β-sheet (1628 cm–1) components and visualization of their spatial distributions in vivo. Notably, the 1628 cm–1/1658 + 1628 cm–1 ratio was significantly lower in the anterior region of the head, indicating region-specific differences in protein composition. Following imaging, worms recovered normal locomotion and retained reproductive capability, demonstrating that the method is minimally invasive and reversible. Overall, this work establishes a quantitative IR imaging framework for analyzing protein structure in living organisms at the micrometer scale. The combination of reversible immobilization and second-derivative spectral narrowing provides a powerful approach for investigating spatial variations in biomolecular structure in vivo.
Related
- Dye-affinity functionalized magnetic nanoparticles enable direct immobilization of cellulase from cell-free microbial culture medium
- Mild hyperbaric oxygen modulates selected proteolytic and mitochondrial markers during cast immobilization in mice
- Hindlimb Muscle Morphology and Function in a New Atrophy Model Combining Spinal Cord Injury and Cast Immobilization
- Adsorption-crosslinking immobilization of SHSL on NKA macroporous resin: Operational stability and molecular dynamics at the enzyme-resin interface.
- Advanced HKUST/MWCNT/Cellulose Acetate Hybrid Support for β-Glucosidase Immobilization: Enhanced Stability, Catalytic Performance, and Reusability
BibTeX
@article{wakita2026minimally,
title = {{Minimally Invasive Infrared Imaging of Caenorhabditis elegans Enabled by Reversible Chemical Immobilization and Second-Derivative Spectral Mapping}},
author = {Nodoka Wakita and Akiko Ito and Ryu Sato and Akihisa Terakita and Tatsuro Nishikino and Mitsumasa Koyanagi and Yuji Furutani},
journal = {ACS Omega},
year = {2026},
month = aug,
doi = {10.1021/acsomega.6c03485},
url = {https://doi.org/10.1021/acsomega.6c03485},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Minimally Invasive Infrared Imaging of Caenorhabditis elegans Enabled by Reversible Chemical Immobilization and Second-Derivative Spectral Mapping
AU - Nodoka Wakita
AU - Akiko Ito
AU - Ryu Sato
AU - Akihisa Terakita
AU - Tatsuro Nishikino
AU - Mitsumasa Koyanagi
AU - Yuji Furutani
PY - 2026
DA - 2026/08/26
JO - ACS Omega
DO - 10.1021/acsomega.6c03485
UR - https://doi.org/10.1021/acsomega.6c03485
AB - The nematode Caenorhabditis elegans is a widely used model organism, yet its infrared (IR) spectroscopic characterization has been limited by motion and strong water absorption in the mid-infrared region. Here, we establish a minimally invasive mid-infrared imaging method for C. elegans by combining reversible immobilization with sodium azide (NaN3) and measurements in deuterium oxide (D2O). NaN3 effectively suppressed locomotion without inducing irreversible physiological damage, enabling high-quality acquisition of IR images. Mid-IR hyperspectral data were analyzed to extract lipid- and protein-specific bands for each pixel, followed by second-derivative analysis of the Amide I band to resolve protein secondary-structure components. This allowed decomposition of α-helical (1658 cm–1) and β-sheet (1628 cm–1) components and visualization of their spatial distributions in vivo. Notably, the 1628 cm–1/1658 + 1628 cm–1 ratio was significantly lower in the anterior region of the head, indicating region-specific differences in protein composition. Following imaging, worms recovered normal locomotion and retained reproductive capability, demonstrating that the method is minimally invasive and reversible. Overall, this work establishes a quantitative IR imaging framework for analyzing protein structure in living organisms at the micrometer scale. The combination of reversible immobilization and second-derivative spectral narrowing provides a powerful approach for investigating spatial variations in biomolecular structure in vivo.
SN - 2470-1343
ER -