Cheng & Tian’s Newest Microscopy Advance Published by Nature Communications

By Allison Kleber

Professor Ji-Xin Cheng’s research group has made notable strides in improved chemical  imaging technologies, especially for medical purposes, over the last few years. Their latest, the development of a new type of mid-infrared photothermal (MIP) microscope, was published by Nature Communications in December. The paper, co-authored by collaborator Professor Lei Tian, Post-Doctoral Associate Jian Zhao, and Alex Matlock (PhD ‘21), describes the eponymous “Bond-selective Intensity Diffraction Tomography” (BS-IDT) technique, which builds on previous explorations into MIP microscopy invented by the Cheng lab and commercialized by Photothermal Spectroscopy Corp. Ultimately, the goal of these investigations is to develop holographic and computational chemical imaging technologies which can capture molecular information more thoroughly and quickly than ever before, enabling the advancement of biological research and therapeutic breakthroughs.

The paper begins by discussing existing imaging methods and their inadequacies, including various potential forms of damage to the specimen, limited molecular specificity (where specific, too-similar biochemical compounds and subcellular structures are rendered indistinguishable), and unwieldy complexity that makes systems difficult to replicate or operate with accuracy, as well as simply falling short of the desired operational speed and depth of resolution.

Professor Cheng’s team shares the results of a series of four experiments, making up an initial investigation of their new method’s potential applications and efficacy.  The BS-IDT device is used to successfully extract specific forms of data from several samples, from single cells to a multicellular organism (C. elegans, a small worm), providing an initial demonstration of its capacity for fast, high-fidelity imaging which can differentiate between different chemical compounds (“bond-selective”). The researchers also built their device as an add-on to a simple, inexpensive off-the-shelf microscope, significantly reducing the complexity issue and improving speed while minimizing various errors.

You can read the full article at Nature Communications here.

Professor Ji-Xin Cheng is the Theodore Moustakas Chair Professor in Photonics and Optoelectronics, and the recipient of numerous honors including the Pittsburgh Spectroscopy Award in 2020, and the Ellis R. Lippincott Award from Optica and the Society for Applied Spectroscopy in 2019. Alongside his colleague Lei Tian, he was recently awarded $1.36M by the Chan Zuckerberg Foundation towards his research into advanced biomedical imaging techniques.

Assistant Professor Lei Tian recently received $1.31M in research funding from the Chan Zuckerberg Foundation, towards continued biomedical imaging advancements. He joined the Department of Electrical and Computer Engineering in 2016, and has been honored with a BU College of Engineering Early Career Excellence Award (2021) and an NSF CAREER Award (2019), among many other accolades.