Abstract
Here, we report a novel and unique application of a special hydrophobic carbon dot (HCD) to monitor biomolecular self-assembly along with the detection of metastable intermediates and self-aggregates. We exploited the restricted rotation of the S-S bond of the HCD synthesized from dithiosalicylic acid and melamine to exhibit different emission behaviors during the self-assembly of amino acids and proteins. The HCD that exhibits blue emission in amino acid droplets or protein aggregates dynamically changes its emission from blue to red with the time course of the amino acid self-assembly process. This unique and distinct change in emission can be visualized by the naked eye under a UV lamp. The ability of HCD to distinguish the biomolecular self-aggregated structures and monitor the self-assembly dynamics can be utilized for the visual detection of uncontrolled aggregation of proteins and peptides related to neurodegenerative diseases like Alzheimer’s and Parkinson’s disease.
Supplementary materials
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Supporting Information
Description
Further information on the chemicals and experimental methods, synthesis protocol of HCD, CAY CD, and CAU CD, HR-TEM and AFM images of HCD for size measurement, FTIR of the precursors and HCD, XPS of HCD, Photophysical properties of HCD in different solvents, Emission spectra at different excitation for HCD in acetic acid and powdered form, HR-TEM and AFM images of aggregated HCD, Bright-field and confocal images of HCD in ethanol and water, Time-dependent emission of HCD, CAY-ZF, CAU-ZF, ThT-ZF, Nile red-ZF, and HCD-ZF/M3+, CLSM images of different protein aggregates without any external dyes or HCD, Emission spectra of HCD in different protein aggregates, Live CLSM imaging of HCD in ZF self-assembly (Supplementary figures S1-S15 and Supplementary movie S1).
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Title
Supporting Movie S1
Description
Live CLSM imaging of HCD in ZF self-assembly
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