ORCID Profile
0000-0002-6998-8462
Current Organisation
University of California, San Diego
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Publisher: Wiley
Date: 05-11-2021
Abstract: Polymer nanocapsules have demonstrated significant value in materials science and biomedical technology, but require complicated and time‐consuming synthetic steps. We report here the facile synthesis of monodisperse polymer nanocapsules via a redox‐mediated kinetic strategy from two simple molecules: dopamine and benzene‐1,4‐dithiol (BDT). Specifically, BDT forms core templates and modulates the oxidation kinetics of dopamine into polydopamine (PDA) shells. These uniform nanoparticles can be tuned between ≈70 and 200 nm because the core diameter directly depends on BDT while the shell thickness depends on dopamine. The supramolecular core can then rapidly disassemble in organic solvents to produce PDA nanocapsules. Such nanocapsules exhibit enhanced physicochemical performance (e.g., loading capacity, photothermal transduction, and anti‐oxidation) versus their solid counterparts. Particularly, this method enables a straightforward encapsulation of functional nanoparticles providing opportunities for designing complex nanostructures such as yolk–shell nanoparticles.
Publisher: American Chemical Society (ACS)
Date: 28-12-2022
Publisher: Wiley
Date: 14-01-2022
Abstract: The transmission of SARS‐CoV‐2 coronavirus has led to the COVID‐19 pandemic. Nucleic acid testing while specific has limitations for mass surveillance. One alternative is the main protease (M pro ) due to its functional importance in mediating the viral life cycle. Here, we describe a combination of modular substrate and gold colloids to detect M pro via visual readout. The strategy involves zwitterionic peptide that carries opposite charges at the C‐/N‐terminus to exploit the specific recognition by M pro . Autolytic cleavage releases a positively charged moiety that assembles the nanoparticles with rapid color changes ( t min). We determine a limit of detection for M pro in breath condensate matrices nM. We further assayed ten COVID‐negative subjects and found no false‐positive result. In the light of simplicity, our test for viral protease is not limited to an equipped laboratory, but also is amenable to integrating as portable point‐of‐care devices including those on face‐coverings.
Publisher: Wiley
Date: 15-12-2023
Abstract: Aromatic interactions are commonly involved in the assembly of naturally occurring building blocks, and these interactions can be replicated in an artificial setting to produce functional materials. Here we describe a colorimetric biosensor using co‐assembly experiments with plasmonic gold and surfactant‐like peptides (SLPs) spanning a wide range of aromatic residues, polar stretches, and interfacial affinities. The SLPs programmed in DDD−(ZZ) x −FFPC self‐assemble into higher‐order structures in response to a protease and subsequently modulate the colloidal dispersity of gold leading to a colorimetric readout. Results show the strong aggregation propensity of the FFPC tail without polar DDD head. The SLPs were specific to the target protease, i.e., M pro , a biomarker for SARS‐CoV‐2. This system is a simple and visual tool that senses M pro in phosphate buffer, exhaled breath condensate, and saliva with detection limits of 15.7, 20.8, and 26.1 nM, respectively. These results may have value in designing other protease testing methods.
Publisher: Wiley
Date: 14-01-2022
Abstract: The transmission of SARS‐CoV‐2 coronavirus has led to the COVID‐19 pandemic. Nucleic acid testing while specific has limitations for mass surveillance. One alternative is the main protease (M pro ) due to its functional importance in mediating the viral life cycle. Here, we describe a combination of modular substrate and gold colloids to detect M pro via visual readout. The strategy involves zwitterionic peptide that carries opposite charges at the C‐/N‐terminus to exploit the specific recognition by M pro . Autolytic cleavage releases a positively charged moiety that assembles the nanoparticles with rapid color changes ( t min). We determine a limit of detection for M pro in breath condensate matrices nM. We further assayed ten COVID‐negative subjects and found no false‐positive result. In the light of simplicity, our test for viral protease is not limited to an equipped laboratory, but also is amenable to integrating as portable point‐of‐care devices including those on face‐coverings.
Publisher: American Chemical Society (ACS)
Date: 25-07-2022
Publisher: American Chemical Society (ACS)
Date: 18-01-2022
Publisher: American Chemical Society (ACS)
Date: 05-08-2022
Publisher: American Chemical Society (ACS)
Date: 16-07-2021
DOI: 10.1021/JACS.1C04272
Abstract: Patchy nanoparticles featuring tunable surface domains with spatial and chemical specificity are of fundamental interest, especially for creating three-dimensional (3D) colloidal structures. Guided assembly and regioselective conjugation of polymers have been widely used to manipulate such topography on nanoparticles however, the processes require presynthesized specialized polymer chains and elaborate assembly conditions. Here, we show how small molecules can form 3D patches in aqueous environments in a single step. The patch features (e.g., size, number, conformation, and stereoselectivity) are modulated by a self-polymerizable aromatic dithiol and comixed ligands, which indicates an autonomous assembly mechanism involving covalent polymerization and supramolecular assembly. Moreover, this method is independent of the underlying nanoparticle material and dimension, offering a streamlined and powerful toolset to design heterogeneous patches on the nanoscale.
Publisher: American Chemical Society (ACS)
Date: 16-08-2022
Publisher: American Chemical Society (ACS)
Date: 08-03-2022
Publisher: Wiley
Date: 15-12-2023
Abstract: Aromatic interactions are commonly involved in the assembly of naturally occurring building blocks, and these interactions can be replicated in an artificial setting to produce functional materials. Here we describe a colorimetric biosensor using co‐assembly experiments with plasmonic gold and surfactant‐like peptides (SLPs) spanning a wide range of aromatic residues, polar stretches, and interfacial affinities. The SLPs programmed in DDD−(ZZ) x −FFPC self‐assemble into higher‐order structures in response to a protease and subsequently modulate the colloidal dispersity of gold leading to a colorimetric readout. Results show the strong aggregation propensity of the FFPC tail without polar DDD head. The SLPs were specific to the target protease, i.e., M pro , a biomarker for SARS‐CoV‐2. This system is a simple and visual tool that senses M pro in phosphate buffer, exhaled breath condensate, and saliva with detection limits of 15.7, 20.8, and 26.1 nM, respectively. These results may have value in designing other protease testing methods.
Publisher: Wiley
Date: 05-11-2021
Abstract: Polymer nanocapsules have demonstrated significant value in materials science and biomedical technology, but require complicated and time‐consuming synthetic steps. We report here the facile synthesis of monodisperse polymer nanocapsules via a redox‐mediated kinetic strategy from two simple molecules: dopamine and benzene‐1,4‐dithiol (BDT). Specifically, BDT forms core templates and modulates the oxidation kinetics of dopamine into polydopamine (PDA) shells. These uniform nanoparticles can be tuned between ≈70 and 200 nm because the core diameter directly depends on BDT while the shell thickness depends on dopamine. The supramolecular core can then rapidly disassemble in organic solvents to produce PDA nanocapsules. Such nanocapsules exhibit enhanced physicochemical performance (e.g., loading capacity, photothermal transduction, and anti‐oxidation) versus their solid counterparts. Particularly, this method enables a straightforward encapsulation of functional nanoparticles providing opportunities for designing complex nanostructures such as yolk–shell nanoparticles.
Location: United States of America
No related grants have been discovered for Ming Xu.