Myoglobin and Polydopamine‐Engineered Raman Nanoprobes for Detecting, Imaging, and Monitoring Reactive Oxygen Species in Biological Samples and Living Cells

Abstract

Highly reliable detection, imaging, and monitoring of reactive oxygen species (ROS) are critical for understanding and studying the biological roles and pathogenesis of ROS. This study describes the design and synthesis of myoglobin and polydopamine-engineered surface-enhanced Raman scattering (MP-SERS) nanoprobes with strong, tunable SERS signals that allow for specifically detecting and imaging ROS sensitively and quantitatively. The study shows that a polydopamine nanolayer can facilitate the modification of Raman-active myoglobins and satellite Au nanoparticles (s-AuNPs) to a plasmonic core AuNP (c-AuNP) in a controllable manner and the generation of plasmonically coupled hot spots between a c-AuNP and s-AuNPs that can induce strong SERS signals. The six-coordinated Fe(III)-OH of myoglobins in plasmonic hotspots is reacted with ROS (H O , •OH, and O ) to form Fe(IV)O. The characteristic Raman peaks of Fe(IV)O from the Fe-porphyrin is used to analyze and quantify ROS. This chemistry allows for these probes to detect ROS in solution and image ROS in cells in a highly designable, specific, and sensitive manner. This work shows that these MP-SERS probes allow for detecting and imaging ROS to differentiate cancerous cells from noncancerous cells. Importantly, for the first time, SERS-based monitoring of the autophagy process in living cells under starvation conditions is validated.

Intracellular and Cellular Detection by SERS‐Active Plasmonic Nanostructures

“…synthesized a AuNR based SERS‐active nanoprobe through the assembly of 4‐mercaptophenylboronic ester . To enhance the electromagnetic field, Nam and co‐workers described the design of a myoglobin and polydopamine (pdop)‐engineered SERS (MP‐SERS) core–satellite nanoprobe (Figure ) . The 80 nm AuNPs coated with pdop were used as the core, and 10 nm AuNPs and ROS‐responsive myoglobin were further adhered on the sticky pdop surface.…”

“…[33] To enhance the electromagnetic field, Nam and co-workers described the designo famyoglobin and polydopamine (pdop)-engineered SERS (MP-SERS)c ore-satellite nanoprobe ( Figure 2). [34] The 80 nm AuNPs coated with pdop were used as the core, and 10 nm AuNPs and ROS-responsive myoglobin were furthera dhered on the sticky pdop surface. Thus, hot spots can be generated between the core and the satellites, andc onsiderably improvethe SERS signals of myoglobin.…”

Spherical Gold Nanoparticles (AuNPs) Formation by Selected Intracellular Protein Fraction of Fungi

“…Gold nanoparticles (AuNPs) are the tiny particles of gold with a diameter of 1-100 nm. It possesses distinct physicochemical properties such as high electron density, dielectric properties, and good biocompatibility, gaining interest in technological applications such as sensors [1,2], electronic devices [3], bioimaging [4,5], and catalysis [6,7]. It is well known that the size and shape of AuNPs play a vital role in their performance and application, giving those remarkable electrical and optical properties and meeting the application of practical technology.…”

Targeted Live Cell Raman Imaging and Visualization of Cancer Biomarkers with Thermal‐Stimuli Responsive Imprinted Nanoprobes

“…Recently, Raman imaging has emerged as a promising tool for the direct visualisation of cells, tissues, and their contents . The Raman signal of the molecularly specific Raman reporter is enhanced by exciting localized surface plasmons within metallic nanostructures, which can provide enhancements with several orders of magnitude greater than conventional Raman scattering .…”