The Golgi apparatus is an essential subcellular organelle. Targeting and monitoring the Golgi change at the single-cell level over a long time scale are critical but are challenges that have not yet been tackled. Inspired by the precise Golgi positioning ability of galactosyltransferase and protein kinase D, due to their cysteine residues, we developed a method for long-term Golgi imaging. Fluorescent molecules, carbon quantum dots (CQDs) and silica nanoparticles could target the Golgi when they are modified with L-cysteine. L-Cysteine-rich chiral carbon quantum dots (LC-CQDs), which have the benefits of a high Golgi specificity from L-cysteine and excellent photostability and biocompatibility from the CQDs, are proven to be highly suitable for long-term in situ imaging of the Golgi. Investigation of the mechanism showed that free thiol groups and the L-type stereo configuration of LC-CQDs are essential for specific targeting of the Golgi. With the aid of the as-prepared LC-CQDs, the dynamic changes of the Golgi in the early stage of viral infection were visualized. The Golgi targeting and imaging strategy used in this work is beneficial for Golgi-targeted drug delivery and early diagnosis and therapy of Golgi diseases.

A β-cyclodextrin functionalized graphene oxide and curcumin composite was developed with excellent antiviral activity against the respiratory syncytial virus.

Single-layered graphene quantum dots with dual recognition sites including π-conjugated single sheets and positively charged sites were developed and used for monitoring the mitochondrial ATP fluctuation in living cells.

In this work, a novel method for colorimetric detection of cysteine was proposed based on the inhibition of peroxidase-like behavior of AuNPs. Kiwi juice prepared gold nanoparticles presented strong catalytic activity, which could catalyze H₂O₂–TMB to generate a blue product, resulting in strong absorption at 650 nm. In HAc–NaAc (pH 4.0) buffer, cysteine induced the aggregation of gold nanoparticles through covalent Au–S bonds and electrostatic as well as hydrogen bonding, leading to the reduction of the catalytic activity of gold nanoparticles with a weakened blue color product and a lower absorbance. Under optimal conditions, the concentrations of cysteine were proportional to the degree of reduced absorbance. This approach offers a new, simple, sensitive and selective assay for cysteine.