Research

Label-free super-resolution coherent Raman Scattering (SRS/CARS) microscopy

The spatial resolution of conventional coherent Raman scattering (i.e., stimulated Raman scattering (SRS), coherenianti-Stokes Raman scatering (CARS)) microscopy is difraction limited. We aim to develop new methods by breaking the diffraction limit for super-resolution label-free biomolecular imaging.

Our previous research includes:

Higher-Order Coherent anti-Stokes RamanScattering (HO-CARS) Microscopy

Saturated Stimulated Raman Scattering (SSRS)Microscopy

Supercritical Focusing Coherent anti-StokesRaman Scattering (SCF-CARS) Microscopy

Fiberoptic Raman endoscopy and imaging for cancer diagnosis

We have developed a rapid fiberoptic confocalRaman endoscopy platform for improving real-time in vivo cancer diagnosis during endoscopic examination.
We further developed the Raman-specified real-time cancer diagnosis model using multivariate analysis and deep learning models together with in vivo tissue Raman spectra.
We have also developed a submillimete fiberoptic Raman needle probe for enhancing realtime in vivo deep tissue and biofluid Raman measurements.

Multimodal nonlinear microscopy for label-free imaging of living cells and tissue

We have developed a multimodal nonlinear optical microscopy imaging platform that consist of two-photon fluorescence (TPF), second/third harmonic generation (SHG/THG), specral-focusing hyperspectral stimulated Raman scattering (h-SRS) and coherent Anti-Stokes Raman scattering (CARS) modalities.

Our imaging system can rapidly acquire the complementary and multidimensional information with sub-cellular spatial resolutiorfrom unstained biological/biomedical cells and tissues.

Hyperspectral Stimulated Raman Scattering (hs-SRS) Microscopy for Real-Time Monitoring of Drug Delivery and Therapeutic Efficacy in Living Systems

We have developed a rapid spectral-focusing hyperspectral stimulated Raman scattering (hs-SRS) microscopy with advantages of providing both the biochemical compositions and structural confirmation about the tissue and cells, high sensitivity and chemical specificity, as well as 3D optical sectioning abilities. We employ this powerful label-free hs-SRS imaging technique in numerous biomedical studies, especially in investigating thedynamic interactions between small molecule drugs and living systems.

Intraoperative Caner Margin Delineation UsingWide-field Multicolor Fluorescence Dynamic lmaging (WMFDI)

To detect cancer margins rapidly and reliably, we designed a novel, non-invasive imaging system based on Wide-field Multicolor Fluorescence Dynamic Imaging (WMFDl). This imaging system measures the autofluorescence lifetimeas the molecular microenvironment indicator and allows for rapid acquisition of tissue intrinsic properties over a large field of view.

System characterization indicates that the least detectable fluorescence lifetime is around 70 ps over 30 mm x 35 mm field of view at the speed of 3 frames per second.

Hybrid Raman Spectroscopy and Optical Coherence Tomography

We have developed a handheld side-view RS-OCT probe that enables simultaneous RS/OCT measurements and characterization invivo. Additionally, we have successfully created the field's thinnest co-axial RS-OCT probe.

We have also developed a compact and efficient double-clad-fiber (DCF) and graded-index (DCF-GRIN) fiber optic Raman probe with an outer diameter of 140 um. This probe allows for real-time, invivo tissue Raman spectroscopy (RS) measurements.