MoS2 is a two-dimensional material that is gaining prominence due to its unique electronic and chemical properties. Here, we demonstrate ligand conjugation of chemically exfoliated MoS2 using thiol chemistry. Using this method, we modulate the zeta-potential and colloidal stability of MoS2 sheets through ligand designs, thus enabling its usage as a selective artificial protein receptor for β-galactosidase. The facile thiol functionalization route opens the door for surface modifications of solution processable MoS2 sheets.

Two‐dimensional bio‐dynamite: Chemically exfoliated MoS2 (ceMoS2), a water‐dispersible sheet‐like material, is an efficient near‐infrared (NIR) photothermal transducer. The superior bio‐supramolecular properties of ceMoS2 and the ability of this material to destroy biomolecular targets through near‐infrared (NIR) photothermal transduction were studied (see picture).

Establishing processing–structure–property relationships for monolayer materials is crucial for a range of applications spanning optics, catalysis, electronics and energy. Presently, for molybdenum disulfide, a promising catalyst for artificial photosynthesis, considerable debate surrounds the structure/property relationships of its various allotropes. Here we unambiguously solve the structure of molybdenum disulfide monolayers using high-resolution transmission electron microscopy supported by density functional theory and show lithium intercalation to direct a preferential transformation of the basal plane from 2H (trigonal prismatic) to 1T′ (clustered Mo). These changes alter the energetics of molybdenum disulfide interactions with hydrogen (ΔGH), and, with respect to catalysis, the 1T′ transformation renders the normally inert basal plane amenable towards hydrogen adsorption and hydrogen evolution. Indeed, we show basal plane activation of 1T′ molybdenum disulfide and a lowering of ΔGH from +1.6 eV for 2H to +0.18 eV for 1T′, comparable to 2H molybdenum disulfide edges on Au(111), one of the most active hydrogen evolution catalysts known.

Key Points Question What are the incidence of and outcomes associated with neurologic manifestations in patients with COVID-19? Findings In this cohort study of 3744 patients in 2 large consortia, neurological manifestations were found in approximately 80% of patients hospitalized with COVID-19; the most common self-reported symptoms included headache (37%) and anosmia or ageusia (26%), whereas the most common neurological signs and/or syndromes were acute encephalopathy (49%), coma (17%), and stroke (6%). Presence of clinically captured neurologic signs and/or syndromes was associated with increased risk of in-hospital death. Meaning These findings suggest that neurological manifestations are prevalent among patients hospitalized with COVID-19 and are associated with higher in-hospital mortality.

We have investigated the efficacy of graphene oxide (GO) in modulating enzymatic activity. Specifically, we show that graphene oxide can mimic as an artificial receptor and inhibit the activity of α-chymotrypsin (ChT), a serine protease. Most significantly, our data demonstrate that GO exhibits the highest inhibition dose response (by weight) for α-chymotrypsin inhibition compared to all other reported artificial inhibitors. Through fluorescence spectrometry and circular dichroism (CD) studies, we show that this protein-receptor interaction is highly biocompatible and conserves the protein’s secondary structure over extended periods (>24 h). We have also explored GO-enzyme interaction by controlling the ionic strength of media, which attenuates the host-guest electrostatic interaction. These findings suggest a new generation of enzymatic inhibitors that can be applied to other complex proteins by systematic modification of GO functionality.