Correlative Optical Spectroscopy and Mass Spectrometry Imaging Methodology to Visualise Drug Distribution in a Soft...

Area of Science:

• Biomedical Imaging
• Analytical Chemistry
• Pharmacokinetics

Background:

• Understanding drug distribution in biological tissues is crucial for drug development and efficacy.
• Existing imaging techniques often lack the sensitivity or spatial resolution required for detailed chemical analysis.
• Correlative imaging offers a potential solution by combining multiple analytical methods.

Purpose of the Study:

• To develop and validate a new correlative imaging methodology for visualizing chemical distribution in soft tissues.
• To assess the distribution of a nonsteroidal anti-inflammatory drug (diclofenac) in excised human skin tissue.
• To integrate optical and mass spectrometry imaging data for comprehensive analysis.

Main Methods:

• Utilized non-destructive optical spectroscopic methods (stimulated Raman scattering, second harmonic generation, two-photon fluorescence microscopy) for structural mapping.
• Employed time-of-flight secondary ion mass spectrometry (ToF-SIMS) for sensitive detection of diclofenac.
• Developed image registration techniques to combine data from optical and mass spectrometry imaging.

Main Results:

• Successfully visualized the distribution of diclofenac within the epidermis and dermis of excised skin tissue.
• Demonstrated sub-micron spatial resolution for imaging tissue morphology.
• Achieved sensitive drug detection, enabling detailed mapping of chemical distribution.

Conclusions:

• The developed correlative imaging methodology provides high-resolution visualization of tissue structure and sensitive chemical detection.
• This approach is valuable for investigating drug distribution in skin and other soft biological tissues.
• Combines label-free imaging with sensitive chemical analysis for enhanced biological insights.