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An important design aspect of electronic cigarettes (“e-cigarettes”) is the nature of the acid/base chemistry in the e-liquid phase. E-liquids having formulations similar to those of early products are mixes of propylene glycol/glycerol (PG/GL) plus free-base (fb) nicotine and (usually), flavor chemicals that are either non- or rather-weak acid/base actors in PG/GL. The fraction of nicotine in the fb form is denoted (αfb)e-liquid; the possible range is 0 less then (αfb)e-liquid less then 1. For e-liquids of an early design, (αfb)e-liquid ≈ 1. Because e-cigarette aerosols high in fb-nicotine are harsh upon inhalation, many commercial e-liquids now also contain variable levels of an acid additive (e.g., benzoic acid, levulinic acid, etc.) to protonate the nicotine, and form dissolved “nicotine salts” (αfb)e-liquid values significantly less than 1 are now common. A framework is developed for predicting αfb values in a given medium based on 1) acid/nicotine ratios; and 2) overall acid+nicotine protonation constant (Koa) values. This framework is required for understanding 1) e-liquid design as regards how acid additives affect (αfb)e-liquid; and 2) demonstrating the inability to measure native (αfb)e-liquid values by any method using dilution with water.In this work, we designed and fabricated Pd/Au bimetallic thin film electrodes with isolated Pd nanoparticles via underpotential deposition of copper on a gold substrate followed by in situ redox replace reaction in a Pd salt solution. The Pd/Au electrode was characterized by AFM and XPS as well as multiple electrochemical techniques including CV and electrochemical quartz crystal microbalance (EQCM) in sulfuric acid and phosphate buffer electrolytes. Results show that the reduction reactions of the analytes (i.e., H2O2 and 3-nitrotyrosine (3-NT)) at the Pd/Au thin film surfaces affect the nature and reactivity of Pd/Au surface electrochemistry including the adsorbed/absorbed hydrogen and/or the premonolayer palladium oxide redox processes at Pd. The EQCM experiment supports the arrangement of small size Pd nanoparticles in the Pd thin film in the presence of gold exhibits unusual properties, acting as a new physicochemical dimension between the electrode and target H2O2 and 3-NT molecules. The Pd/Au thin film was demonstrated as an extremely sensitive and selective probe for detection of common ROS and RNS (i.e., H2O2 and 3-NT). The integration of two different metallic species, Pd and Au, into a surface structure on nanoscale by exploiting their unique surface electrochemistry establishes an innovative analytical method for highly sensitive and selective detection of H2O2 and 3-NT simultaneously. This method has a general scope for detecting a broad range of redox active and nonredox active species simultaneously, which opens up new opportunities to develop new electrocatalytic materials and innovative sensing approaches.The limited efficacy of “smart” nanotheranostic agents in eradicating tumors calls for the development of highly desirable nanoagents with diagnostics and therapeutics. Isradipine concentration Herein, to surmount these challenges, we constructed an intelligent nanoregulator by coating a mesoporous carbon nitride (C3N4) layer on a core-shell nitrogen-doped graphene quantum dot (N-GQD)@hollow mesoporous silica nanosphere (HMSN) and decorated it with a P-PEG-RGD polymer, to achieve active-targeting delivery (designated as R-NCNP). Upon irradiation, the resultant R-NCNP nanoregulators exhibit significant catalytic breakdown of water molecules, causing a sustainable elevation of oxygen level owing to the C3N4 shell, which facilitates tumor oxygenation and relieves tumor hypoxia. The generated oxygen bubbles serve as an echogenic source, triggering tissue impedance mismatch, thereby enhancing the generation of an echogenicity signal, making them laser-activatable ultrasound imaging agents. In addition, the encapsulated photosensitizers and C3N4-layered photosensitizer are simultaneously activated to maximize the yield of ROS, actualizing a triple-photosensitizer hybrid nanosystem exploited for enhanced PDT. Intriguingly, the N-GQDs endow the R-NCNP nanoregulator with a photothermal effect for hyperthemia, making it exhibit considerable photothermal outcomes and infrared thermal imaging (IRT). Importantly, further analysis reveals that the polymer-modified R-NCNPs actively target specific tumor tissues and display a triple-modal US/IRT/FL imaging-assisted cooperative PTT/PDT for real-time monitoring of tumor ablation and therapeutic evaluation. The rational synergy of triple-model PDT and efficient PTT in the designed nanoregulator confers excellent anticancer effects, as evidenced by in vitro and in vivo assays, which might explore more possibilities in personalized cancer treatment.PSS has been studied as a silicon-based binder due to its inherent superior electricity and electrochemical stability. However, it cannot effectively alleviate the huge volume changes of silicon during lithiation/delithiation due to its linear structure, resulting in poor cycling stability. Ion-cross-linking is a usual method to cross-link linear polymers into 3D structures. In this paper, multivalent cations of the 5th period and Group 2 cross-linked PEDOTPSS were applied as silicon anode binders and studied systematically. It was found that the variation trend of viscosity and conductivity of PEDOTPSS after cross-linking was consistent with that of ionic potential and softness parameters of multivalent cations. The mesostructure of a binder after cross-linking is influenced by the solubility product constant of sulfites or hydroxides of cations and the growth characteristics of crystals. An Sn4+-cross-linked binder displayed increased viscosity and electrical conductivity and higher reduced modulus and hardness due to its positive softness parameter and higher ion potential. The Si electrode with the Sn4+-cross-linked binder showed improved cycling stability (1876.4 mAh g-1 compared with 1068.4 mAh g-1 of the electrode with the pure PEDOTPSS binder after 100 cycles) and superior rate capability (∼800 mAh g-1 at an ultrahigh current density of 8.0 A g-1).