Probing Perovskite Carrier Dynamics under Sunlight

Understanding the nature of photogenerated carriers and their subsequent dynamics in perovskites is important for the development of related materials and devices. Most ultrafast dynamic measurements on the perovskite materials were conducted under high carrier densities, which likely obscures the genuine dynamics at low carrier densities under solar illumination conditions. In this study, we presented a detailed experimental study of the carrier density-dependent dynamics in hybrid lead iodide perovskites using a highly sensitive transient absorption spectrometer. We found that the carrier lifetime was about a hundred nanosecond in the linear response range, representing sunlight excitation, which was much longer than under high carrier densities. We also elucidated that the fast carrier decay (<1 ps) and the medium decay processes (tens of ps) occurred via the defect state trapping, and we determined its effects on the utilization percentage of photogenerated carriers through quantitative analysis. Furthermore, we obtained the Shockley-Queisser limit that took into account the carrier trapping effect, which directly reflected the material performance.

A Sensitive Electrochemical Sensor Based on Sonogel-Carbon Material Enriched with Gold Nanoparticles for Melatonin Determination

In this work, the development of an electrochemical sensor for melatonin determination is presented. The sensor was based on Sonogel-Carbon electrode material (SNGCE) and Au nanoparticles (AuNPs). The low-cost and environmentally friendly SNGCE material was prepared by the ultrasound-assisted sonogel method. AuNPs were prepared by a chemical route and narrow size distribution was obtained. The electrochemical characterization of the SNGCE/AuNP sensor was carried out by cyclic voltammetry in the presence of a redox probe. The analytical performance of the SNGCE/AuNP sensor in terms of linear response range, repeatability, selectivity, and limit of detection was investigated. The optimized SNGCE/AuNP sensor displayed a low detection limit of 8.4 nM melatonin in synthetic samples assessed by means of the amperometry technique. The potential use of the proposed sensor in real sample analysis and the anti-matrix capability were assessed by a recovery study of melatonin detection in human peripheral blood serum with good accuracy.

Maximizing the Surface Sensitivity of LSPR Biosensors through Plasmon Coupling—Interparticle Gap Optimization for Dimers Using Computational Simulations

The bulk and surface refractive index sensitivities of LSPR biosensors, consisting of coupled plasmonic nanosphere and nano-ellipsoid dimers, were investigated by simulations using the boundary element method (BEM). The enhancement factor, defined as the ratio of plasmon extinction peak shift of multi-particle and single-particle arrangements caused by changes in the refractive index of the environment, was used to quantify the effect of coupling on the increased sensitivity of the dimers. The bulk refractive index sensitivity (RIS) was obtained by changing the dielectric medium surrounding the nanoparticles, while the surface sensitivity was modeled by depositing dielectric layers on the nanoparticle in an increasing thickness. The results show that by optimizing the interparticle gaps for a given layer thickness, up to ~80% of the optical response range of the nanoparticles can be utilized by confining the plasmon field between the particles, which translates into an enhancement of ~3–4 times compared to uncoupled, single particles with the same shape and size. The results also show that in these cases, the surface sensitivity enhancement is significantly higher than the bulk RI sensitivity enhancement (e.g., 3.2 times vs. 1.8 times for nanospheres with a 70 nm diameter), and thus the sensors’ response for molecular interactions is higher than their RIS would indicate. These results underline the importance of plasmonic coupling in the optimization of nanoparticle arrangements for biosensor applications. The interparticle gap should be tailored with respect to the size of the used receptor/target molecules to maximize the molecular sensitivity, and the presented methodology can effectively aid the optimization of fabrication technologies.

Preparation and Characterization of Pt-Doped Bi2MoO6 Nanocomposites and Its High PDT Efficiency on HL60 Cells

In this study, Pt-doped Bi2MoO6 nanocomposites were prepared by solvothermal and in situ reduction method. We used XRD, UV-Vis spectroscopy, TEM, EDS, and XPS to characterize its chemical properties. Results showed that the Pt-doped Bi2MoO6 nanocomposites had advantages of small size, good dispersion, and wide spectral response range. Then, we tested its biological toxicity and PDT efficiency on HL60 cells. Both pure Bi2MoO6 and Pt-doped Bi2MoO6 nanocomposites showed great biocompatibility after coincubated with leukemia cells for 12 h in the dark. As to PDT efficiency, Pt-doped Bi2MoO6 had a better-inactivated effect than pure Bi2MoO6. Furthermore, the PDT efficiency went up when atomic ratios and concentration increased. While the atomic ratio was 5% and the concentration was 1000 μg/mL, it reached the highest value at 85.2%. At last, we briefly analyzed the photocatalysis mechanism, which demonstrated that it was a potential photosensitizer with high efficiency for treating leukemia.

Deformation mechanism of copper reinforced by three-dimensional graphene under torsion and tension

The mechanical behaviors of uniaxial torsional and tensional copper nanorod embedded with sp2-type hybrid graphene nanosheets (3DG/Cu) were investigated systematically using molecular dynamics methods. During the torsion process, graphene expanded the plastic deformation region of copper, while the plastic deformation in monocrystalline Cu cases was limited to a smaller area. 3DG/Cu responded to the torsion by one more plastic stage when plastic deformation spread along the length after the elastic response. Graphene improved the torsional loading capacity of the composite material, greatly extending the effective response range of the material by distributing the deformation of copper along with the graphene rather than being concentrated at a certain position like monocrystalline Cu. Generally, as the length of the model increased, this enhancement decreased. The copper portion of 3DG/Cu was divided into three areas during uniaxial tensile, a static region, a quasi-static region of the middle portion where the shear and necking occurred, and a dynamic area near the loading end. However, the inside graphene kept continuous until fracture. Furthermore, graphene improved the yield strain of copper by maintaining intact after copper failure. The greater the pre-loaded torsion angle, the smaller the yield strength and Young's modulus of 3DG/Cu.

Photoelectrochemical and Photo-Fenton Mechanism of Enhanced Visible Light-Driven Nanocatalyst Synthesis of ZnFe2O4/BiOI

Based on the fact that the photo-Fenton process can directly use solar energy to degrade various pollutants, it has received widespread attention. However, it has attracted widespread attention due to the rapid recombination of photo-generated carriers and the low light response range. Therefore, the construction of a Z-scheme heterojunction in this paper can effectively enhance the electron-hole separation, increase the reduction and oxidation potential, and enhance the redox capability of the photocatalyst. This paper reports the successful preparation of visible-light-induced ZnFe2O4/BiOI composite photocatalyst. There is a Z-scheme heterojunction structure of ZnFe2O4 and BiOI. At the same time, the PL and UV absorption spectra showed that the light absorption performance of the composite nanomaterials was enhanced, the photo-generated carriers recombination rate was reduced, and the photo-Fenton performance was also significantly improved. And the photocurrent of ZnFe2O4/BiOI is more than 29 times that of pure ZnFe2O4. In addition, ZnFe2O4/BiOI can degrade the simulated pollutant RhB 100% within 20 min under simulated sunlight. It shows that ZnFe2O4/BiOI binary composite has excellent photo-Fenton properties. In addition, ZnFe2O4/BiOI still maintains a high photo-Fenton ability after three cycles. Therefore, it has potential application prospects of the industrial photodegradation of organic pollutants.

Non-Enzymatic Amperometric Glucose Screen-Printed Sensors Based on Copper and Copper Oxide Particles

Non-enzymatic amperometric glucose sensors have gained much attention in the past decade because of the better chemical and thermal stability and biocompatibility compared to conventional sensors based on the use of biomolecules. This study focuses on a novel copper and copper oxide-based glucose sensor synthesized by an electrodeposition technique through a rigorous protocol which reports an excellent analytical performance due to its structure and its increased active area. In addition, the linear response range, detection limit and sensitivity were 0.5–5.0 mmol L−1, 0.002 mmol L−1, 904 μA mmol−1 L−1 cm−2, respectively. Results show a reliable electrode as it is chemically stable, exhibits rapid and excellent sensitivity, and it is not significantly affected by coexisting species present in the blood samples; furthermore, it reports a maximum relative standard deviation error (RSD) of 6%, and showed long operating life as the electrode was used for thousand measurements of 4.0 mmol L−1 glucose solution during three days.

Application of a Conducting Poly-Methionine/Gold Nanoparticles-Modified Sensor for the Electrochemical Detection of Paroxetine

This work demonstrates a facile electropolymerization of a dl-methionine (dl-met) conducting polymeric film on a gold nanoparticle (AuNPs)-modified glassy carbon electrode (GCE). The resulting sensor was successfully applied for the sensitive detection of paroxetine·HCl (PRX), a selective serotonin (5-HT) reuptake inhibitor (SSRIs), in its pharmaceutical formulations. The sensor was characterized morphologically using scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM) and electrochemical techniques such as differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The proposed sensor, poly (dl-met)/AuNPs-GCE, exhibited a linear response range from 5 × 10−11 to 5 × 10−8 M and from 5 × 10−8 to 1 × 10−4 M using DPV with lowest limit of detection (LOD = 1 × 10−11 M) based on (S/N = 3). The poly (dl-met)/AuNPs-GCE sensor was successfully applied for PRX determination in three different pharmaceutical formulations with percent recoveries between 96.29% and 103.40% ± SD (±0.02 and ±0.58, respectively).

Updated Organ Response Results of an Open-Label Study to Evaluate the Safety and Tolerability of Cael-101 in Patients with AL Amyloidosis Receiving Anti-Plasma Cell Therapy

Background: CAEL-101 is an IgG1 monoclonal antibody intended to enable immune clearance of AL amyloid deposits. This study (NCT04304144) data allowed dose selection of CAEL-101 for the ongoing Phase 3 studies in patients with Mayo stage IIIa and IIIb AL amyloidosis cardiomyopathy newly diagnosed and treated with bortezomib, cyclophosphamide, and dexamethasone (CyBorD) alone or in combination with daratumumab. Methods: 13 patients were treated with CAEL-101 and CyBorD and an additional 5 patients were treated with CAEL-101, daratumumab, and CyBorD. Organ response data on assessable patients were evaluated per consensus criteria as per institutional standard of care. Safety, pharmacokinetic and anti-drug antibody data will be reported separately. Results: The follow up for patients receiving CAEL-101 and CyBorD is 12 to 15 months and for the CAEL-101, Daratumumab, and CyBorD is 4 to 6 months. 16 of 18 patients remain on treatment. One discontinuation was due to death from E. coli sepsis and the other due to lack of hematologic response with deterioration of heart function requiring heart transplant after only 6 doses of CAEL-101. Organ response in cardiac patients by NT pro BNP criteria occurred in 4 of 8 evaluable patients treated with CAEL-101 and CyBorD (time to organ response range 2 - 12 months) and in 2 of 3 patients treated with CAEL-101, daratumumab, and CyBorD (time to organ response range 3 - 5 months). Four patients have had repeat echocardiogram 1 year from start of CAEL-101 based therapy with interpretable global peak longitudinal strain (GLS). The GLS improved in 2 patients by -5% (-6.4% to -11.4%) and -5.1% (-12.8% to -17.9%). GLS remained stable in the other 2 patients. All 9 patients with evaluable kidney involvement by 24 hour urine protein achieved an organ response. Responses occurred in as little as 2 months in 5 patients (range 2 - 7 months). The time to organ response were similar in the daratumumab and non-daratumumab treated patients. One patient with hematologic stable disease and persistent 71% improvement in 24 hour urine protein at 10 months from start of CAEL-101 based therapy is most notable. Conclusions: CAEL-101 with anti-plasma cell therapy remains reasonably well tolerated with no unanticipated adverse effects. Organ responses, most notably renal response, have occurred early in the course of therapy and appears to be durable. Organ responses in some patients have also improved over time with some significant improvement in patient GLS evaluations by echocardiogram. These results encourage clinical trial participation in the ongoing CAEL-101 clinical trials in Mayo stage IIIa and IIIb AL amyloidosis patients. Disclosures Valent: Celgene Corporation: Speakers Bureau; Amgen: Speakers Bureau; Caelum Biosciences: Other: Clinical Trial Funding; Takeda Pharmaceuticals: Speakers Bureau. Silowsky: Caelum Biosciences: Current Employment. Kurman: Caelum Biosciences: Other: Medical Monitor. Daniel: Caelum Biosciences: Current Employment. Jobes: Caelum Biosciences: Current Employment. Harnett: Caelum Biosciences: Current Employment. Spector: Caelum Biosciences: Current Employment. Anwer: GlaxoSmithKline: Research Funding; Allogene Therapeutics: Research Funding; Janssen pharmaceutical: Honoraria, Research Funding; BMS / Celgene: Honoraria, Research Funding. Zonder: BMS: Consultancy, Research Funding; Janssen: Consultancy; Caelum Biosciences: Consultancy; Intellia: Consultancy; Regeneron: Consultancy; Amgen: Consultancy; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Alnylam: Consultancy. Liedtke: Kura Oncology: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Kite: Membership on an entity's Board of Directors or advisory committees; Alnylam: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees; Janssen Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Caelum: Membership on an entity's Board of Directors or advisory committees, Other: Clinical Trial Funding; Celgene: Membership on an entity's Board of Directors or advisory committees. Sobolov: Caelum Biosciences: Current Employment. OffLabel Disclosure: CAEL-101 is a monoclonal antibody directed at AL amyloid deposits. The purpose is to promote immune clearance of amyloid deposits.