Widefield quantitative multiplex surface enhanced Raman scattering imaging in vivo

Area of Science:

• Molecular Imaging
• Biomedical Optics
• Spectroscopy

Background:

• Surface-enhanced Raman scattering (SERS) offers potential for in vitro and in vivo molecular imaging.
• Traditional point-scanned SERS imaging methods suffer from low throughput, limiting biological applications.
• There is a need for faster, quantitative imaging techniques for SERS-based contrast agents.

Purpose of the Study:

• To demonstrate direct widefield Raman imaging for quantitative multiplex SERS imaging in vivo.
• To achieve significantly reduced acquisition times compared to point-scanned methodologies.
• To validate the utility of widefield Raman imaging in biological applications.

Main Methods:

• Development of a direct widefield Raman imaging system utilizing a tunable filter for small animal imaging.
• Quantitative assessment of the system's linear response range (0.01 to 100 pM).
• Demonstration of multiplex imaging capability with four simultaneous SERS reporter molecules in vivo.

Main Results:

• The widefield Raman imaging system achieved quantitative multiplex SERS imaging in vivo.
• Typical in vivo images were acquired in less than 10 seconds, orders of magnitude faster than point-scanned methods.
• Probe quantification showed excellent agreement with known quantities (R² > 0.98), without spectral overlap compensation.

Conclusions:

• Direct widefield Raman imaging enables rapid, quantitative, and multiplexed in vivo SERS imaging.
• This technique overcomes the throughput limitations of traditional methods for biological imaging.
• The demonstrated system holds significant promise for advancing molecular imaging applications in small animals.