Engineered nanomedicines block the PD-1/PD-L1 axis for potentiated cancer immunotherapy.

Immunotherapy, in particular immune checkpoint blockade (ICB) therapy targeting the programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) axis, has remarkably revolutionized cancer treatment in the clinic. Anti-PD-1/PD-L1 therapy is designed to restore the antitumor response of cytotoxic T cells (CTLs) by blocking the interaction between PD-L1 on tumour cells and PD-1 on CTLs. Nevertheless, current anti-PD-1/PD-L1 therapy suffers from poor therapeutic outcomes in a large variety of solid tumours due to insufficient tumour specificity, severe cytotoxic effects, and the occurrence of immune resistance. In recent years, nanosized drug delivery systems (NDDSs), endowed with highly efficient tumour targeting and versatility for combination therapy, have paved a new avenue for cancer immunotherapy. In this review article, we summarized the recent advances in NDDSs for anti-PD-1/PD-L1 therapy. We then discussed the challenges and further provided perspectives to promote the clinical application of NDDS-based anti-PD-1/PD-L1 therapy.

[Comprehensive Study of Lead Speciation and Its Bioavailability in Soils From a Lead/Zinc Mining Area by Micro X-Ray Fluorescence and X-Ray Absorption Near-Edge Structure].

Lead species significantly influences its mobility and bioavailability. In this study, improved BCR procedure, laboratory culture, laboratory micro X-ray fluorescence (µ-XRF), and synchrotron radiation X-ray absorption near-edge structure (XANES) were used to investigate the distribution, speciation, and bioavailability of Pb in soils from a Pb/zinc (Zn) mining area contaminated with heavy metals. The results showed that ① Pb was mainly distributed in the reducible[which binds to oxides of iron (Fe) and manganese (Mn)], acid soluble, residual, and oxidizable fractions, ② Pb content in plant tissues correlated with acid-soluble Pb content in soil, ③ µ-XRF results indicated that Pb was distributed heterogeneously, and correlated with the hot spot with high concentration of Mn. In some area, Pb also correlated with Fe, and ④ Pb was predominantly present as Pb-goethite (41%-46%), Pb3(PO4)2(36%-55%), and Pb-MnO2(3%-24%) in soil samples. The results of this study showed that oxides of Fe and Mn, and Pb3(PO4)2precipitate mainly comprise the pool of Pb in soils.

Fully Coated Semitransparent Organic Solar Cells with a Doctor-Blade-Coated Composite Anode Buffer Layer of Phosphomolybdic Acid and PEDOT:PSS and a Spray-Coated Silver Nanowire Top Electrode.

In the aim to realize high performance semitransparent fully coated organic solar cells, printable electrode buffer layers and top electrodes are two important key technologies. An ideal ink for the preparation of the electrode buffer layer for printed top electrodes should have good wettability and negligible solvent corrosion to the underlying layer. This work reports a novel organic-inorganic composite of phosphomolybdic acid (PMA) and PEDOT:PSS that features excellent wettability with the active layer and printed top Ag nanowires and high resistibility to solvent corrosion. This composite buffer layer can be easily deposited on a polymer surface to form a smooth, homogeneous film via spin-coating or doctor-blade coating. Through the use of this composite anode buffer layer, fully coated semitransparent devices with doctor-blade-coated functional layers and spray-coated Ag nanowire top electrodes showed the highest power conversion efficiency (PCE) of 5.01% with an excellent average visible-light transmittance (AVT) of 50.3%, demonstrating superior overall characteristics with a comparable performance to and a much higher AVT than cells based on a thermally evaporated MoO3/Ag/MoO3 thin film electrode (with a PCE of 5.77% and AVT of 19.5%). The current work reports the fabrication of fully coated inverted organic solar cells by combining doctor-blade coating and spray coating and, more importantly, demonstrates that a nanocomposite of a polyoxometalate and conjugated polymer could be an excellent anode buffer layer for the fully coated polymer solar cells with favorable interfacial contact, hole extraction efficiency, and high comparability with full printing.

Electrosynthesis of bismuth nanodendrites/gallium nitride electrode for non-enzymatic hydrogen peroxide detection.

Bismuth nanodendrites (BiNDs) were electrodeposited on planar gallium nitride (GaN) electrode via a differential pulse voltammetric technique to fabricate the non-enzymatic hydrogen peroxide (H2O2) sensor. SEM images revealed that the as-obtained BiNDs had numerous dendrite sub-branches, whose diameters ranged from 136 to 152nm. The BiNDs/GaN electrode showed linear amperometric responses for H2O2 in the concentration range from 10µM to 1mM with the sensitivity of 60.0µAmM-1cm-2. Another linear range was from 1 to 10mM with the sensitivity of 23.3µAmM-1cm-2. The limit of detection (LOD) was 5µM with the signal-to-noise ratio of 3. The applicability of the sensor was investigated to the H2O2 detection in real samples such as fetal bovine serum and milk, and the sensor exhibited excellent anti-interference capacity. The achieved results indicate that the as-prepared BiNDs/GaN sensor with good reproducibility and long-term stability was promising for detecting H2O2 in practical environments.

Label-free electrochemical impedance genosensor based on 1-aminopyrene/graphene hybrids.

In this work, we proposed a novel simple protocol for preparing 1-aminopyrene/graphene (ApG) hybrids for fabricating label-free electrochemical impedance genosensor. Graphene, with the structure of a single-atom-thick sheet of sp(2)-bonded carbon atoms, was anchored to 1-aminopyrene (1-Ap) with the pyrenyl group viaπ-stacking interaction. The morphology, conductivity, and interaction of ApG hybrids were characterized by transmission electron microscopy (TEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), UV-visible (UV-vis) and fluorescence spectra. The amino-substituted oligonucleotide probe was conjugated to 1-Ap by the cross-linker glutaraldehyde. The DNA hybridization reaction of oligonucleotide probe with target DNA was monitored by EIS. Under optimum conditions, the proposed biosensor exhibited high sensitivity and a low detection limit for detecting the complementary oligonucleotide. The target oligonucleotide could be quantified in a wide range of 1.0 × 10(-12) to 1.0 × 10(-8) M with good linearity (R = 0.9900) and low detection limit of 4.5 × 10(-13) M (S/N = 3).

[XANES study of lead speciation in duckweed].

Qixiashan lead-zinc mine of Nanjing was one of the largest lead zinc deposits in East China Its exploitation has been over 50 years, and the environmental pollution has also been increasing. The lead concentration in the local environment was high, but lead migration and toxic mechanism has not been clear. Therefore, biogeochemistry research of the lead zinc mine was carried out. Using ICP-MS and Pb-L III edge XANES, lead concentration and speciation were analyzed respectively, and duckweed which can tolerate and enriched heavy metals was found in the pollution area. The results showed that the lead concentration of duckweed was 39.4 mg x kg(-1). XANES analysis and linear combination fit indicated that lead stearate and lead sulfide accounted for 65% and 36.9% respectively in the lead speciation of duckweed, suggesting that the main lead speciation of duckweed was sulfur-containing lead-organic acid.

[In vivo determination of Pb in human bone by using X-ray fluorescence analysis].

The data of in vivo XRF Pb in human bone were obtained within China by using the in vivo XRF set. The K series X-ray of Pb were applied to determine the in vivo Pb concentration in tibia and calcaneus among Chinese mainland residents. For general population, the weighted average of Pb in bone was 0.4-22.7 microg x (lead g bone mineral)(-1). The uncertainty was 7.0-12.5 microg x (lead g bone mineral)(-1), and the average minimun detection limit was 20.3 microg x (lead g bone mineral)(-1). For residents from pollution area, the maximum Pb in bone reached up to 73.9 microg x (lead g bone mineral)(-1).

[EDXRF analysis of soil heavy metals on lead-zinc orefield].

Due to the impact of lead-zinc mining and smelting, the soil of lead-zinc orefield and nearby areas has been widely polluted. Moreover, the concentration of lead and zinc was high, and their concentration range was wide. Furthermore, the impact of overlapping interference between low concentration As and high Pb was serious, and the lack of soil standards of lead and zinc was also a problem. According to these problems, the present work studied an effective solution to setting up the EDXRF analysis of Pb, As, Cd, Cu and Zn of soil on lead-zinc orefield. The measurable concentration of Pb was 4.4-23 600 microg x g(-1), and that of Zn was 7.0-39 400 microg x g(-1). The detection limit was 1.1 microg x g(-1) for Pb and 0.9 microg x g(-1) for Zn. The average relative-error was 7.6% for Pb and 6.2% for Zn.

[Resolution of overlapped spectra in polarization X-ray fluorescence spectrometry by genetic algorithm].

Overlapped spectra occur often in energy dispersive X-ray fluorescence spectrometry. Without a suitable curve fitting process, no correct qualitative and quantitative results can be obtained. The most difficult problems in curve fitting include that elements and their lines are unknown, background is uncertain sometimes, and initial model parameters may be in correct. In order to solve these problems, several available algorithms may be used. Among them are genetic algorithms. In the present work, polarization energy dispersive X-ray spectrometry was used in the determination of raw materials for permanent magnet. A genetic algorithm was successfully applied to the deconvolution of the overlapped spectra in magnetic materials. With its global searching capability, the genetic algorithm beatures higher resolution than the standard Marquardt-Levenberg method in resolving the overlapped X-ray spectra. Because of the powerful capability of genetic algorithms to deconvolute overlapped spectra, the algorithms are useful especially in energy dispersive X-ray spectrometry and complex material analysis.