Ultrasmall Magneto-chiral Cobalt Hydroxide Nanoparticles Enable Dynamic Detection of Reactive Oxygen Species in Vivo

Abstract

Biological application of chiral nanoparticles (NPs) has aroused enormous levels of attention over recent years. Here, we synthesized magneto-chiral cobalt hydroxide (Co(OH) 2 ) NPs that exhibited strong chiroptical and unique magnetic properties and applied these NPs to detect and monitor reactive oxygen species (ROS) in living cells and in vivo. Circular dichroism (CD) and magnetic resonance imaging (MRI) signals of the magneto-chiral Co(OH) 2 NPs exhibited a wide intracellular ROS detection range from 0.673 to 612.971 pmol/10 6 cells with corresponding limits of detection (LOD) at 0.087 and 0.179 pmol/10 6 cells, far below that of currently available probes; the LOD for D-aspartic acid coated Co(OH) 2 NPs (D-Co(OH) 2 NPs) was 5.7 times lower than that for L-aspartic acid coated Co(OH) 2 NPs (L-Co(OH) 2 NPs) based on the CD signals. In addition, D-Co(OH) 2 NPs also exhibited dynamic ROS monitoring ability. The high levels of selectivity and sensitivity to ROS in complex biological environments can be attributed to the Co 2+ oxidation reaction on the surface of the NPs. Furthermore, magneto-chiral Co(OH) 2 NPs were able to quantify the levels of ROS in living mice by fluorescence and MRI signals. Collectively, these results reveal that magneto-chiral Co(OH) 2 NPs exhibit a remarkable ability to quantify ROS levels in living organisms, and could therefore provide new tools for exploring chiral nanomaterials as a potential biosensor to investigate biological events.

Multi-Mimic Activities of Co3O4 Nanopolyhedrons and Application in Regulating the Content of Intracellular Hydrogen Peroxide/Oxygen

“…Also, the produced oxygen in normal cells is relatively less than that in tumor cells, which may result from the lower concentration of H 2 O 2 in the LO2 cells. It is important to evaluate the cell uptake ability of the nanomaterials, 56 which can be realized by ICP-MS or similar methods (confocal and flow cytometry). Here, the Co content in cells was tested using the inductively coupled plasma emission mass spectrometer.…”

Biomimetic Self-Assembled Chiral Inorganic Nanomaterials: A New Strategy for Solving Medical Problems

“…Another pathway that induces autophagy is the activation of AMPK, which inhibits the activity of mTOR [ 101 , 102 , 103 , 104 ]. Chen et al synthesized L/D-Co(OH) 2 NPs and modified them with fluorescent molecules (Alexa Fluor 568 (AF568)) to achieve the quantitative detection of ROS levels in vivo under the dual signal of CD and MRI [ 105 ]. The study found that the D-Co(OH) 2 NPs performed with a lower cytotoxicity and higher cellular uptake compared to the L-Co(OH) 2 NPs, and because of the denser distribution of the D-Co(OH) 2 NPs in the cellular microenvironment, they also had a stronger ROS detection ability at low concentrations.…”

Chiral nanomaterials for biosensing, bioimaging, and disease therapies

“…[9][10][11][12] Because natural chiral compounds have the advantages of safety and biocompatibility, they have been used to fabricate a series of chiral nanostructures, which in turn can affect biological functions and fates. 13,14 The interactions between multifunctional chiral nanomaterials and biological systems are extensive and facilitate applications ranging from chirality-dependent biosensing, 15 bioimaging, 16 biocatalysis, 17 and the regulation of cell behavior 18 to disease diagnosis and treatment. [19][20][21] Therefore, chiral bio-nanoscience is a novel and popular research area, which provides an excellent platform to address the growing demand for bio-applications.…”