LAMMP/BME Seminar Series

Wednesday 25th of April 2018
12:00 PM
Beckman Laser Institute Library

Advances in Biophotonics for Imaging and Sensing

Malini Olivo, PhD and Ignatius Rasiah, Phd
Agency for Science Technology & Research Singapore National University of Singapore

The growing demand for reliable and robust methodology in medical diagnostics calls for continuous advancement of biosensor and bio-imaging technologies. In this context, in our research group, we develop novel nano-photonics methods combined with nano-materials to answer various problems in the field of cancer, metabolic medicine, skin and neurodegeneration. Novel optical methods currently being developed fall under two major categories, namely surface-enhanced Raman spectroscopy (SERS) and surface plasmon resonance (SPR) for bio-sensing applications, as well as photoacoustic imaging (PAI), hybrid imaging combining near-infrared spectroscopy (NIRS) with high field MRI.

In this talk, I will be focusing on our recent advances in the field of SERS as an ultrasensitive and molecular specific bio-sensing platform, specifically for the detection of various biomarkers and in the development of biosensors. SERS detection relies on the giant amplification of the vibrational ‘fingerprint’ of the Raman scatter signal when the analyte is in a close proximity to nano-roughened silver or gold coated substrates/colloids and fibers. SERS biosensor platforms are developed using novel nanomaterial concepts integrated with substrates or optical fiber platforms. In vivo biomarker detection using SERS-active nanoparticles will also be discussed.

On the bio-imaging frontier, our recent advances in the field of Photoacoustic Imaging (PAI) will be presented . This will include Multispectral optoacoustic tomography (MSOT ) and Rastar scanning optoacoustic mesoscopy (RSOM) clinical trials on first-in-man skin studies and also Photoacoustic Microscopy (PAM) applications in neuroscience. PAI is rapidly progressing as a promising bio-imaging photonics strategy because by combining the diffuse-light excitation and un-scattered ultrasonic wave detection that lead to increased penetration depth by nearly two orders of magnitude. PAI is being investigated for clinical anatomical imaging of organs and blood vasculature, functional imaging of hemodynamics and blood oxygenation in tumour models, lipid/fat imaging in human skin, human breast and also in pre-clinical disease models. Various PA contrast agents that are being investigated in our lab includes photosensitizers and nano-sensitizers, organic and organo-metallic molecules. Multimodal (SERS & PAI ) imaging probes that are being developed will also be discussed. Cutting edge advancement on combining the strategies of PAI with MRI will also be presented.