Year: 2023
Type: article
Abstract: Quantitative phase imaging (QPI) is a powerful optical imaging modality for label-free, rapid, and three-dimensional (3D) monitoring of cells and tissues. However, molecular imaging of important intracellular biomolecules such as enzymes remains a largely unexplored area for QPI. Herein, we introduce a fundamentally new approach by designing QPI contrast agents that allow sensitive detection of intracellular biomolecules. We report a new class of bio-orthogonal QPI-nanoprobes for in situ high-contrast refractive index (RI) imaging of enzyme activity. The nanoprobes feature silica nanoparticles (SiO 2 NPs) having higher RI than endogenous cellular components and surface-anchored cyanobenzothiazole-cysteine (CBT-Cys) conjugated enzyme-responsive peptide sequences. The nanoprobes specifically aggregated in cells with target enzyme activity, increasing intracellular RI and enabling precise visualization of intracellular enzyme activity. We envision that this general design of QPI-nanoprobes could open doors for spatial–temporal mapping of enzyme activity with direct implications for disease diagnosis and evaluating the therapeutic efficacy.
Source: Nano Letters
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: Intracellular Self-Assembly of Theranostic Nanoparticles for Enhanced Imaging and Tumor Therapy, Spectroscopy assisted mechano-chemical phenotype recognition nanoscope, Determination of functional and molecular biomarkers of treatment resistance with multimodal optical spectroscopy, MIT Laser Biomedical Research Center, G743101891, Resource for Molecular Imaging Agents in Precision Medicine
OpenAlex ID: W4375860616