Related Experiment Video
Updated: May 24, 2026
Transient Optical Clearing Using Absorbing Molecules for Ex Vivo and In Vivo Imaging
Published on: July 11, 2025
Optical clearing of porcine skin tissue in vitro studied by Raman microspectroscopy
Deqiu Huang1, Wen Zhang, Huiqing Zhong
1South China Normal University, Laboratory of Photonic Chinese Medicine, MOE Key Laboratory of Laser Life Science, College of Biophotonics, 510631, Guangzhou, Guangdong, China.
Abstract:
In present work, we studied the effect of optical clearing on porcine skin in vitro with glycerol by Raman microspectroscopy, denoted as RM, at various time intervals of 0, 15, 30, 45, 60, and 75 min respectively. The results showed that the addition of glycerol significantly improved the depth of RM measurement, and enhanced the recovery of skin tissue Raman spectra that were not overlapped with the glycerol Raman spectra over time. Moreover, it was found that the Raman signals resembled the native spectrum of the molecules in porcine skin with a negligible frequency shift. Furthermore, we evaluated the extent of optical clearing in porcine skin by utilizing various concentrations of 40%, 60%, and 80% glycerol solution. The results demonstrated that with the increase of concentration of glycerol, the optical clearing of porcine skin was much improved.
Insights
Glycerol enhances optical clearing in porcine skin, improving Raman microspectroscopy measurements. Higher glycerol concentrations lead to better optical clearing and clearer tissue spectra.
Area of Science:
- Biomedical Optics
- Spectroscopy
- Dermatology
Background:
- In vitro studies are crucial for understanding tissue optical properties.
- Raman microspectroscopy (RM) provides molecular information but is limited by light scattering in tissues.
- Optical clearing aims to reduce scattering and improve RM penetration depth.
Purpose of the Study:
- To investigate the efficacy of glycerol for optical clearing of porcine skin.
- To evaluate the impact of glycerol concentration and incubation time on RM measurements.
- To assess the quality and integrity of Raman spectra after optical clearing.
Main Methods:
- Porcine skin samples were treated with glycerol solutions (40%, 60%, 80%).
- Raman microspectroscopy (RM) was performed at various time intervals (0-75 min).
- Changes in measurement depth and spectral quality were analyzed.
Main Results:
- Glycerol significantly increased the depth of RM measurements in porcine skin.
- Incubation with glycerol enhanced the recovery of distinct skin tissue Raman spectra.
- Higher glycerol concentrations (up to 80%) progressively improved optical clearing.
- Raman signals showed minimal frequency shifts, indicating preserved molecular information.
Conclusions:
- Glycerol is an effective optical clearing agent for porcine skin in vitro.
- This technique enhances the capabilities of Raman microspectroscopy for skin analysis.
- Optimized glycerol concentration and time are key for improved spectral acquisition.
