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This method allows us to accurately estimate the concentration of these resuspended carbon nanotubes, after removing bundles and micrometric aggregates, which can be used as a calibration standard, for dosage-dependent studies in biological systems. This method can also be extended to any other nanomaterial to properly quantify the actual concentration.Silver sulfide quantum dots (Ag2S QDs) as a theragnostic agent have received much attention because they provide excellent optical and chemical properties to facilitate diagnosis and therapy simultaneously. Ag2S QDs possess brightness and photostability suitable for intense and stable bioimaging. It has been verified via in vitro and in vivo studies that Ag2S QDs do not cause serious toxicity, unlike the first generation of widely used heavy metal-based (cadmium or lead) QDs. In particular, Ag2S QDs emit in the near infrared-II region (NIR-II window) that enables deep tissue penetration and imaging. Furthermore, various chemotherapeutic agents and targeting moieties can be efficiently conjugated to the surface of Ag2S QDs due to advanced technologies in the relevant surface chemistry using covalent bonding, high affinity, and electrostatic interaction. In addition, Ag2S QDs themselves exhibit an anticancer activity based on the photothermal effect. Consequently, Ag2S QDs can function as both a therapeutic agent and an imaging agent in imaging-based diagnosis concurrently, which led to the creation of Ag2S theragnostic nanomaterials. In this review, the synthetic methods, physicochemical properties, bioconjugations, and bioapplications of Ag2S QD theragnostic nanomaterials are discussed in detail.A comprehensive photophysical study of a series of purines, doubly decorated at C2 and C6 positions with identical fragments ranging from electron acceptor to donor groups of different strengths, is presented. The asymmetry of substitutions creates a unique molecular D-A-D’ structure possessing two independent electronic charge transfer (CT) systems attributed to each fragment and exhibiting dual-band fluorescence. Moreover, the inherent property of coordination of metal ions by purines was enriched due to a presence of nearby triazoles used as spacers for donor or acceptor fragments. New molecules present a bidentate coordination mode, which makes the assembly of several ligands with one metal cation possible. This property was exploited to create a new concept of a ratiometric chemical fluorescence sensor involving the photoinduced electron transfer between branches of different ligands as a mechanism of fluorescence modulation.A highly chemoselective as well as enantioselective fluorescent probe has been discovered for the recognition of the acidic amino acids, including glutamic acid and aspartic acid. This study has established a novel amino acid recognition mechanism by an aldehyde-based fluorescent probe.Penta-graphene has been intensively studied owing to its superior properties such as being an intrinsic semiconductor and having two dimensional stability. However, the nonmagnetic character makes it difficult for straightforward application in the fields of spintronic or information storage. Here, the deposition effects of Fe-group and Co-group transition metal (TM = Fe, Ru, Os; Co, Rh, Ir) clusters on the penta-graphene have been systemically investigated for their electronic and magnetic properties by using density functional theory (DFT) calculations. We found that the TM deposition stability on penta-graphene is overall greater than that on graphene. Importantly, TM adatoms (adclusters) not only change penta-graphene from being a wide band-gap semiconductor to a narrow band-gap semiconductor, but also introduce large magnetic moments into systems simultaneously. It is worth noting that the Ir5 cluster on penta-graphene is a good candidate for realizing the magnetic half-metallic materials. Our calculated results demonstrate that adatoms can exhibit large out-of-plane magnetic anisotropy energy, e.g., the Os adatom presents the largest value of 113 meV. Therefore, from the application point of view, magnetic functionalization of penta-graphene by TM clusters facilitates its application as a spintronic device or a high-density information storage device.A unique double-exchange strategy is adopted to access active high-valent transition metal sites during neutral oxygen evolution reaction (OER). This double-exchange is realized through electronic interaction between transition metal ions and foreign dopants in a transition metal oxide. Based on systematical evaluation on dopants with varied d-electron numbers, we demonstrate that the d electron-poor dopant exhibits more significant double-exchange interaction with the transition metal ions, and therefore obtains more active high-valence metal sites, and thus achieves better neutral OER performance.The electron transfer rate constant of an electrochemical reaction and the conductance quantum are fundamental concepts that drive processes ranging from nanoscale electronic circuits to photosynthesis. Ceruletide In this paper, it is demonstrated that they are correlated with the concept of electrochemical capacitance. The relationship between electron transfer rate, quantum transport and electrochemical capacitance encompasses the theory of electron transfer rate proposed by Rudolph A. Marcus, and potentially unites electronics and electrochemistry.A glassy carbon electrode chemically modified with a carbon black coating is proposed here for the rapid and portable determination of cannabidiol (CBD) in a commercial Cannabis seed oil and in fibre-type Cannabis sativa L. leaves. The mechanism of CBD oxidation was studied in relation to simpler phenyl derivatives bearing the same electroactive group, namely resorcinol and 2-methylresorcinol. These molecules also allowed us to determine the best conditions for the electrochemical detection of CBD, as to the pH value and to the best solvent mixture to use. Carbon black was chosen among nanostructured carbon-based materials owing to its outstanding features as an electrode modifier for analyte detection. The performance of the modified electrode was determined by flow injection analyses of standard solutions of CBD, obtaining a linear correlation between the oxidation current and the analyte concentration; the sensor response is characterised by suitable repeatability and reproducibility. The analysis of commercial products by the standard addition method allowed us to ascertain the accuracy of the sensor for the detection of CBD in real samples.