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Synthesis and in-depth biological evaluation of IrCOOH–CaCO3@PEG for acidic microenvironment responsive and luminescence-guided combined Ca2+ overload and two-photon photodynamic therapy.

A mitochondria-localized iridium(iii)–chlorin e6 conjugate was developed for synergistic sonodynamic and two-photon photodynamic therapy against melanoma A375 cells and A375 mice xenografts.

Four novel one-photon and two-photon absorbing PSs (photosensitizers) of nitrogen-heterocyclic ruthenium polypyridyl complexes were reported, and the photodynamic activities of these complexes were studied on 2D and 3D HeLa cancer models.

Chemotherapy continues to be the most commonly applied strategy for cancer. Despite the impressive clinical success obtained with several drugs, increasing numbers of (multi)drug-resistant tumors are reported. To overcome this shortcoming, novel drug candidates and delivery systems are urgently needed. Herein, a therapeutic copper polypyridine complex encapsulated in natural nanocarrier apoferritin is reported. The generated nanoparticles showed higher cytotoxicity toward various (drug-resistant) cancer cell lines than noncancerous cells. The study of the mechanism revealed that the compound triggers cell autophagy-dependent apoptosis. Promisingly, upon injection of the nanodrug conjugate into the bloodstream of a mouse model bearing a multidrug-resistant colon tumor, a strong tumor growth inhibition effect was observed. To date, this is the first study describing the encapsulation of a copper complex in apoferritin that acts by autophagy-dependent apoptosis.

The Jiaonan uplift and its adjacent areas (JUAA) are the result of collision and amalgamation of the North China plate and Yangtze plate. In this area, the tectonic environment is complex and crustal deformation is strong. However, detailed and in-depth study of the upper crustal structure and medium properties in the JUAA has not previously been performed. The high-resolution three-dimensional crustal velocity structure of the JUAA is helpful to analyze the characteristics of the crustal structure in this area and is important for evaluating the tectonic environment and medium properties of the JUAA. We obtained the three-dimensional crustal velocity structure in the JUAA using the double-difference seismic tomography technique, and found that the Rizhao area and the sea areas to its southwest in the Jiaonan uplift are characterized by a high-velocity structure, and that most of the high-velocity anomaly area is located in the sea area. The crustal velocity values of the southern end of the Yishu fault zone are also high. The high crustal velocity anomaly areas in the JUAA are considered to be caused by the upwelling of mantle material. The velocity structure of the upper crust beneath the depression structures shows notable low-velocity anomalies, which are closely related to loose sediments in the depression structures. The existence of abnormally high-velocity and low-velocity structures in the Jiaonan uplift indicates that there are substantial differences in the properties of the crustal media in the Jiaonan uplift. Crust-mantle interaction in the Jiaonan uplift is mainly concentrated in the Rizhao area and sea areas to its southwest.

High amounts of glutathione in tumour cells are able to decrease the effectiveness of cancer treatments by capturing the therapeutically necessary reactive oxygen species during the photodynamic therapy (PDT) process. In addition, many photosensitizers for PDT are limited by the light tissue penetration depth, which hinders the application of these compounds to treat deep seated or large tumors. To overcome the aforementioned drawbacks, herein, the use of a mitochondrial-targeting iridium(III) prodrug Ir–B(OH)2 which is responsive to the tumour microenvironment (H2O2 rich) and able to release two-photon photosensitizers (Ir–OH) for PDT and methylquinone as a glutathione scavenger for disrupting the mitochondrial redox homeostasis is presented. Based on the reduction of glutathione, the cancerous cells were more vulnerable to oxidative stress caused by two-photon photodynamic therapy. Upon two-photon laser irradiation (730 nm), a strong and amplified phototoxic effect towards human gastric adenocarcinoma (AGS) cellular and animal models was observed.

As an important part of the North China Craton extension system, the southwest of Shandong Province comprises several uplift and fault depression structures. However, the tectonic activity there is controversial, and more studies are required for the upper crustal velocity structure. In the present study, the three-dimensional upper crustal P wave velocity structure in southwestern Shandong Province was obtained using double-difference seismic tomography. The findings show that southwestern Shandong Province has many vertical high-velocity structures, indicating that mantle-magma upwelling was strong there and formed the uplift structures. It is reasoned that Taishan Mountain is still undergoing uplift caused by magma upwelling that is concentrated mainly below a depth of 20 km. The shallow–middle low-velocity structures in southwestern Shandong Province correspond strongly to the uplift depression structures. The tectonic activity in southwestern Shandong Province can be divided mainly into (i) brittle-ductile deformation of uplift depression structures at depths of 0–10 km and (ii) mantle-magma upwelling under the uplift structures. The formation of uplift structures promoted the formation of the fault depression structures, and the fault depression and uplift structures are closely related in genesis.

This study used the double-difference seismic tomography method to obtain the upper crustal velocity structure in Laizhou Bay and its adjacent areas (LBAA). We found that the horizontal and vertical distributions of the earthquakes after relocation in earthquake swarms are more concentrative than that before relocation. The lateral heterogeneity of crustal velocity structure near the surface in the LBAA is weak, and the low-velocity sedimentary caprocks are developed in most areas except for the Jiaobei uplift. The velocity structure in 5–25 km depth range is highly heterogeneity, which is closely related to different tectonic units. The local uplift tectonic units in Jiyang depression show high-velocity anomalies and should have deep crustal media properties. The high-velocity anomalies under the crust of Tancheng–Lujiang fault zone and the northern Laizhou Bay indicate the properties of upwelling mantle material media. Earthquake swarms activity in the study area are mainly concentrated in the high-velocity interlayer of the upper crust and its periphery. Compared with the relatively stable high-velocity body at the bottom crust, the location of high-velocity interlayer in the study area is more prone to earthquakes under the combined action of gravity and tectonic stress.

Ruthenium(II) and iridium(III) coordination compounds display excellent structural, photophysical, and biological properties which make them highly promising as anticancer and bioimaging agents. When nanoparticles are functionalized with Ru(II) and Ir(III) complexes, enhanced performance and synergistic effects can be produced in the resultant nanosystems. This review begins by describing the three main strategies for the fabrication of Ru(II) and Ir(III) complex containing nanosystems. This is followed by a discussion of the ways in which Ru(II) and Ir(III) complexes and nanoparticles combine and interact to produce novel materials with efficacies exceeding the sum of their parts. The main body of the review then outlines the recent developments in Ru(II) and Ir(III) complex containing nanosystems for cancer treatment and bioimaging. To conclude, some of the future challenges and opportunities in this field are highlighted.

The diagnosis and treatment of cancer is one of the biggest medical challenges of the century. Despite significant improvements, there remains an urgent need for novel anticancer procedures. Among the most promising approaches, increasing attention has been devoted towards photothermal and sonodynamic therapy in which sensitizers are activated upon light/ultrasound radiation to generate a cytotoxic effect. While these methods have undoubtedly shown a high therapeutic success, these techniques are intrinsically limited. Herein, the functionalization of black-titanium nanoparticle with iridium complexes and cancer cell membranes in a nanoplatform for hierarchical targeted synergistic photothermal and sonodynamic cancer imaging and therapy is proposed. The particles showed to generate efficiently heat upon irradiation and catalytically form reactive oxygen species upon ultrasound radiation. The nanoparticle formulation demonstrated to selectively localize in the mitochondria as well as to preferentially accumulate in cancerous over non-cancerous cells as well as in the tumor inside a mouse model, presenting a hierarchical targeting strategy. Upon synergistic irradiation at 1064 nm and ultrasound radiation, the nanoparticles were able to act as an imaging agent and identify the tumor site with high spatial resolution as well as act as a therapeutic agent and completely eradicate a tumor inside a mouse model.

A magnetic sensor for detection of Pb 2+ has been developed based on Fe/Fe 3 O 4 nanoparticles modified by 3-(3,4-dihydroxyphenyl)propionic acid (DHCA). The carboxyl groups of DHCA have a strong affinity to coordination behavior of Pb 2+ thus inducing the transformation of Fe/Fe 3 O 4 nanoparticles from a dispersed to an aggregated state with a corresponding decrease, then increase in transverse relaxation time ( T 2 ) of the surrounding water protons. Upon addition of the different concentrations of Pb 2+ to an aq. solution of DHCA functionalized Fe/Fe 3 O 4 nanoparticles (DHCA-Fe/Fe 3 O 4 NPs) ([Fe] = 90 μmol/L), the change of T 2 values display a good linear relationship with the concentration of Pb 2+ from 40 μmol/L to 100 μmol/L and from 130 μmol/L to 200 μmol/L, respectively. Owing to the especially strong interaction between DHCA and Pb 2+ , DHCA-Fe/Fe 3 O 4 NPs exhibited a high selectivity over other metal ions.

A bifunctional sensor based on Au-Fe 3 O 4 nanoparticles (NPs) modified by ethyl 1-(2-(3′,4′-dihydroxyphenyl)-2-oxoethyl)-1H-1,2,3-triazole-4-carboxylate (ETC) was developed. Due to the coordination interaction between cadmium (Cd 2+ ) and ETC, Cd 2+ induced the aggregation of Au-Fe 3 O 4 NPs from dispersion, concomitant with a change in UV–vis spectra and transverse relaxation time ( T 2 ). The combined signals provided high selectively for Cd 2+ ions.

Magnetic hyperthermia therapy (MHT) and chemodynamic therapy (CDT) are non-invasive in situ treatments without depth limitations and with minimum adverse effects on surrounding healthy tissue. We herein report a mitochondria-targeting magnetothermogenic nanozyme (Ir@MnFe2O4 NPs) for highly efficient cancer therapy. An iridium(III) complex (Ir) acts as a mitochondria-targeting agent on the surface of MnFe2O4 NPs. On exposure to an alternating magnetic field (AMF), the Ir@MnFe2O4 NPs induce a localized increase in temperature causing mitochondrial damage (MHT effect). Meanwhile glutathione (GSH) reduces Fe(III) to Fe(II) on the NPs surface, which in turn catalyzes the conversion of H2O2 to cytotoxic •OH (CDT effect). The depletion of GSH (a •OH scavenger) increases CDT efficacy, while the localized increase in temperature increases the rate of conversion of both Fe(III) to Fe(II) and H2O2 to •OH further enhancing the CDT effect. In addition, the disruption of cellular redox homeostasis due to CDT, leads to greater sensitivity of the cell towards MHT. This nanoplatform integrates these excellent therapeutic properties, with two-photon microscopy (TPM) (demonstrated in vitro) and magnetic resonance imaging (MRI) (demonstrated in vivo) to enable the precise and effective treatment of cancer.

A magnetic sensor for Cd2+ has been developed based on (Zn, Mn)-doped iron oxide nanoparticles [(Zn, Mn)Fe3O4 NPs], which was modified by ethyl 1-(2-(3′,4′-dihydroxyphenyl)-2-oxoethyl)-1H-1,2,3-triazole-4-carboxylate (ETC). ETC provided the binding sites to Cd2+ to induce the transformation of (Zn, Mn)Fe3O4 NPs from a dispersed to an aggregated state with a corresponding increase in the transverse relaxation time (T2) of surrounding water protons. Owing to the special strong interaction between ETC and Cd2+, ETC coordinated (Zn, Mn)Fe3O4 [(ETC-(Zn, Mn)Fe3O4)] NPs exhibited a low limit of detection of Cd2+ of 3.5 nM and a high selectivity over other metal ions. Furthermore, ETC-(Zn, Mn)Fe3O4 NPs can be used to detect Cd2+ in living cells by magnetic resonance (MR) imaging.

The detection for melamine has attracted much attention due to its toxicity to the kidney of animals and humans. Herein, we reported a magnetic relaxation switch (MRSw) assay for melamine with Fe/Fe3O4 nanoparticles functionalized by the dopamine conjugated with methoxypoly (ethylene glycol) carboxyl acid (mPEG-COOH) and (2,4,6-trioxo-1,3,5-triazin-1-yl) acetic acid (TTAA) (TTAA–Fe/Fe3O4 NPs). The approach of the MRSw assay for melamine is based on the aggregation of TTAA–Fe/Fe3O4 NPs induced by the special triple hydrogen bonds between melamine and TTAA, which results in the increase of the spin–spin relaxation time (T2) of surrounding water protons of nanoparticles. Due to no limitation of light scattering, the detection of melamine with the MRSw assay can be performed in a turbid medium without pre-treatment and purification. Upon addition of the different concentration of melamine to an aqueous solution of TTAA–Fe/Fe3O4 NPs ([Fe] = 32 μM), the change of T2 value has a good linear relationship with the concentration of melamine below 16 μM. The limit of detection (LOD) for melamine is ∼2 μM. Furthermore, the MRSw assay exhibits a high selectivity for melamine over cytosine, uracil and thymine with the similar structure.

The development of photothermal agents (PTAs) with good stability, low toxicity, highly targeting ability and photothermal conversion efficiency is an essential pre-requisite to near-infrared photothermal therapy (PTT) in vivo . Herein, we report the readily available PEGylated Fe@Fe 3 O 4 NPs, which possess triple functional properties in one entity – targeting, PTT, and imaging. Compared to Au nanorods, they exhibit comparable photothermal conversion efficiency (∼20%), and much higher photothermal stability. They also show a high magnetization value and transverse relaxivity (∼156 m m −1 s −1 ), which should be applied for magnetic targeting MRI. With the Nd-Fe-B magnet (0.5 T) beside the tumour for 12 h on the xenograft HeLa tumour model, PEGylated Fe@Fe 3 O 4 NPs exhibit an obvious accumulation. In tumour, the intensity of MRI signal is ∼ three folds and the increased temperature is ∼ two times than those without magnetic targeting, indicating the good magnetic targeting ability. Notably, the intrinsic high photothermal conversion efficiency and selective magnetic targeting effect of the NPs in tumour play synergistically in highly efficient ablation of cancer cells in vitro and in vivo .

The feasibility of employing cloud point extraction (CPE) as a simple and effective alternative for recovery of alkaloids from tobacco samples followed by GC–MS analysis is demonstrated. An aqueous surfactant solution containing 5% Triton X114 was used for extraction of tobacco alkaloids. Then, the analytes were back-extracted with ultrasonic assistance from the surfactant-rich phase into dichloromethane. No other cleanup step preceded GC–MS analysis. Seven alkaloids in tobacco sample with different concentrations were analyzed simultaneously. Results show that the recovery of nicotine is 80.4% and the limit of detection (LOD) is 7.1 μg g−1. The relative standard deviations for the seven alkaloids are in the range of 2.77–9.97%. The results yielded by the proposed method were almost identical with those achieved by the more laborious industrial standard method, i.e., the continuous flow method.

A rapid and simple sampling approach using solid phase microextraction (SPME) for pyrethroid residues analysis in flue-cured tobacco was studied. The fibers coated with poly-dimethylsiloxane (PDMS) at 100 microm thickness were chosen. Extraction time of 180 s, desorption time of 120 s and desorption temperature of 280 degrees C were selected. The whole sampling process, only including an ultrasonic assisted extraction step and a solid phase microextraction step, can be completed within 15 min. The associated SPME and ultrasonic assisted extraction using water as extracting solvent shows good results for tobacco pyrethroid residues determination. Results indicated that four pyrethroids can be determined simultaneously, and the limits of detection are below 35 ng g(-1) using GC/MS in selected ion monitoring (SIM) mode. The reproducibility of the technique is found to be better than 11.8% RSD.

The performance of accelerated solvent extraction in the analysis of terpenoids and sterols in tobacco samples was investigated and compared with those of Soxhlet extraction and ultrasonically assisted extraction with respect to yield, extraction time, reproducibility and solvent consumption. The results indicate that although the highest yield was achieved by Soxhlet extraction, ASE appears to be a promising alternative to classical methods since it is faster and uses less solvent, especially when applied to the investigation of large batch tobacco samples. However, Soxhlet extraction is still the preferred method for analyzing sterols since it gives a higher extraction efficiency than other methods.