Deep-red Emitting Ir(III) Complexes as Type-I Photosensitizers for Lipid Droplets Targeted Photodynamic Therapy.

Photodynamic therapy (PDT) relying on photosensitizer-induced production of reactive oxygen species (ROS) for killing cancer cells has emerged as a non-invasive anti-cancer strategy. Compared with oxygen-dependent type-II photosensitizers (PSs) for PDT, the development of intrinsic oxygen-independent type-I ones is highly desired but remains a challenge. In this work, two netural Ir(III) complexes that can produce type-I reactive oxygen species, namely MPhBI-Ir-BIQ (Ir-1) and NPhBI-Ir-BIQ (Ir-2), were synthesized. Bright deep-red emitting nanoparticles with moderate particle size are beneficial for imaging-guided PDT. In in vitro experiments, importantly, the excellent biocompatibility, the targeting of lipid droplets (LDs), and the type-I ⋅OH and O2 ⋅- generation promoted effective photodynamic activity. This work will guide the building of type-I Ir(III) complexes PSs and can provide advantages for potential clinical applications under hypoxic conditions.

Thickness measurements of graphene oxide flakes using atomic force microscopy: results of an international interlaboratory comparison.

Flake thickness is one of the defining properties of graphene-related 2D materials (GR2Ms), and therefore requires reliable, accurate, and reproducible measurements with well-understood uncertainties. This is needed regardless of the production method or manufacturer because it is important for all GR2M products to be globally comparable. An international interlaboratory comparison on thickness measurements of graphene oxide flakes using atomic force microscopy has been completed in technical working area 41 of versailles project on advanced materials and standards. Twelve laboratories participated in the comparison project, led by NIM, China, to improve the equivalence of thickness measurement for two-dimensional flakes. The measurement methods, uncertainty evaluation and a comparison of the results and analysis are reported in this manuscript. The data and results of this project will be directly used to support the development of an ISO standard.

Electro- and photon-induced cooling in BNT-BT-SBET relaxors with in situ optical temperature sensing.

A novel lead-free luminescent ferroelectric (FE) ceramic, ${{\rm Bi}_{0.5}}{{\rm Na}_{0.5}}{{\rm TiO}_3} {-} {0.{06\; \rm BaTiO}_3} {-} {0.{055\;\rm Sr}_{0.7}}{{\rm Bi}_{0.18}}{{\rm Er}_{0.02 \,\square\, 0.1}}$Bi0.5Na0.5TiO3-0.06BaTiO3-0.055Sr0.7Bi0.18Er0.02◻0.1${{\rm TiO}_3}$TiO3 (BNT-BT-SBET), is developed with an adiabatic temperature change ($\Delta T$ΔT) of 0.7 K under an electric field ($E$E) of 60 kV/cm at room temperature, an anti-Stokes fluorescence cooling, and a maximum optical $T$T sensitivity of ${0.0055}\;{{\rm K}^{ - 1}}$0.0055K-1 at 522 K. Interestingly, the electrocaloric response reaches a saturation at permittivity shoulder $T$T of 100°C; meanwhile, the maximized emission intensity of $^2{{\rm H}_{11/2}}{ \to ^4}{{\rm I}_{15/2}}$2H11/2→4I15/2 occurs. $T$T- and $E$E-tunable enhancement of $^2{{\rm H}_{11/2}}{ \to ^4}{{\rm I}_{15/2}}$2H11/2→4I15/2 emission intensity is due to the population inversion from the $^4{{\rm S}_{3/2}}$4S3/2 to $^2{{\rm H}_{11/2}}$2H11/2 states caused by an incoherent regime consisting of FE phase and polar nanoregions in a relaxor matrix.

[Calibration Procedure of Laser Confocal Micro-Raman Spectrometer].

As a common spectral characterization technique, Raman spectroscopy is widely used and has a specified calibration procedure. Based on laser confocal micro-Raman spectrometer, in this paper, we briefly introduced the principle, configuration and main components of Raman spectrometer. In addition, the calibration procedures were also presented, with an emphasis on the calibration of spectrometer (spectrograph) and that of excitation laser wavelength. On the basis of conventional calibration method, a novel and more accurate method was proposed to obtain the actual excitation wavelength, that is, calibration at the point of Raman shift Δν=0. Using this novel calibration method of excitation wavelength, Raman frequency shift values of sulfur were measured, and compared with the standard values from American Society Testing and Materials (ASTM). As a result, the measured values after calibration were consistent with those ASTM values, which indicated that the calibration method is accurate. Thus, a more reasonable calibration procedure of the laser confocal micro-Raman spectrometer was provided.