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It is appealing to develop a facile way to prepare a binary CT contrast agent with good biocompatibility and CT contrast efficiency for potential clinical applications. In this work, a novel binary CT contrast agent based on the biocompatible nano-hydroxyapatite (nHAp, the main inorganic component of human bone and teeth) was prepared facilely and rapidly through doping two kinds of CT contrast ions (Ba 2+ and Ho 3+ ) into the nHAp host via microwave-assisted synthesis. The Ba/Ho co-doped nHAp with pure nHAp phase composition and good mono-dispersion was obtained simply with microwave heating for 30 min. The as prepared CT contrast agent is very promising as a novel binary CT contrast agent for CT imaging. [ABSTRACT FROM AUTHOR]

Cross-linked Chitosan (CS) loaded with iron species has been widely used as heterogeneous Fenton catalysts for organic contaminant removal. In comparison with raw-CS based Fenton catalysts, it exhibited an improved degradation efficiency due to the stabilization of cross-linking agents. With cross-linking, however, most reactive sites of CS were occupied by cross-linking agents, making its capability decreased sharply for adsorbing the released metal ions from metal-complex dye degradation. In this work, in order to efficiently adsorb the released metal ions from metal-complex dyes and avoid a secondary pollution, a new CS-based heterogeneous Fenton catalyst (Chitosan/Hydroxyapatite/Fe 3 O 4 magnetic composite) was developed for AY220 (a model of metal-complex dyes) removal. Hydroxyapatite (HA), a well-known biocompatible material with strong ability for metal ion adsorption, was introduced to combine with CS for Fe 3 O 4 loading. The total removal efficiency of AY220 by the magnetic composite can reach as high as 95.0%, and the degradation efficiency of AY220 was greatly enhanced compared with a raw-CS based catalyst and bare Fe 3 O 4 . Meanwhile, the composite can efficiently adsorb Co 2 + released from AY220 degradation, which can further promote the degradation of AY220. After five recyclable runs of the composite, the degradation efficiency of AY220 increased from 25.1% to 45.6%, demonstrating its potential usefulness in recyclable degradation of metal-complex dyes. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuNCs modified with dual-ligand with high fluorescence and stability were prepared. • Cys-PVP-CuNCs were found to have a specific fluorescence response to Sn4+. • The LOD could reach 5 μg L−1 by observing the fluorescence color change with naked eye. • The proposed probe is simple, portable, stable, selective and highly sensitive. In this study, polyvinylpyrrolidone (PVP) supported and cysteine (Cys) modified copper nanoclusters (Cys-PVP-CuNCs) with high fluorescence intensity have been synthesized and used to establish a simple and sensitive assay for the determination of trace Sn4+. The presence of Sn4+ can lead to fluorescence quenching based on the aggregation of PVP-CuNCs caused by the coordination of Sn4+ and oxygen atoms. For Cys-PVP-CuNCs, the ligand Cys can transfer electrons to the metal center of the cluster, resulting in strong fluorescence enhancement of CuNCs and intensification of fluorescence quenching after interaction with Sn4+, which is conducive to more sensitive visual detection. The proposed assay allows for the detection of Sn4+ in a linear range from 5 μg L−1 to 100 μg L−1, with a detection limit as low as 4.5 μg L−1 at a signal-to-noise ratio of 3. Moreover, under UV light, the obvious fluorescent color change can be observed by naked eyes at Sn4+ concentration ranging from as low as 5 μg L−1 to 200 μg L−1. Benefiting from the high sensitivity of this assay, satisfactory test results have been obtained when using only 10 mg of canned food samples with rapid digestion. The proposed Cys-PVP-CuNCs fluorescent probe shows excellent stability, simple operation, good selectivity, and high sensitivity, and thus it is expected to be used in the real-time field detection of Sn4+. [ABSTRACT FROM AUTHOR]

OV-HAp with abundant oxygen vacancies (OVs) were prepared by calcining carbonate-doped HAp (CHAp), and the effects of calcination temperature, time and atmosphere on the formation of OVs in OV-HAp, as well as the influence of OVs concentration on its photoelectrochemical properties were investigated in detail. Meanwhile, an integrated platform for photocatalytic degradation of TC with online spectral monitoring was constructed, and the feasibility of online spectral monitoring the TC degradation was tentatively explored. [Display omitted] • The effect of different calcination conditions on the oxygen vacancy introduction in OV-HAp was investigated. • The mechanism of oxygen vacancy introduction in OV-HAp and its performance for photocatalytic degradation of TC was proposed. • A platform integrating photocatalytic degradation together with online spectral monitoring was constructed. In this study, OV-HAp with abundant oxygen vacancies (OVs) were prepared by calcining carbonate-doped HAp (CHAp), and the effects of calcination temperature, time and atmosphere on the formation of OVs in OV-HAp and the influence of OVs concentration on its photoelectrochemical properties were investigated in detail. The results showed that the calcination temperature and atmosphere play a major role in the generation of OVs in OV-HAp. Through changing the temperature or atmosphere, the optical absorption range of OV-HAp can be broadened to the visible light and the band gap can be reduced to 1.6 eV. OV-HAp obtained by calcining CHAp at 600℃ for 5 h under H 2 atmosphere (OV-HAp-H 2) exhibited the highest efficiency for tetracycline (TC) photocatalytic degradation (65.4%). h+ and ·O 2 – were demonstrated to be the main active species in the degradation process by radical trapping experiments. Meanwhile, an integrated platform for photocatalytic degradation of TC with online spectral monitoring was constructed, and the feasibility of online spectral monitoring the TC degradation was tentatively explored. This work will provide a theoretical and technical basis for the development of HAp-based high-efficient photocatalysts, and this is favorable for promoting their use by a large scale for water pollutant removal. Moreover, it will also open a new path for online spectral monitoring and kinetic study of photocatalytic degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

As a typical doped quantum dots, Mn doped ZnSe quantum dots (Mn:ZnSe QDs) is widely used for bio-imaging applications due to its excellent optical properties and low toxicity. However, it is difficult to dissolve and easy to oxidize selenium powder. In order to solve this problem, a heterogeneous Se powder instead of homogeneous Se solution was used here as anionic precursor for synthesis of Mn doped ZnSe QDs based on “nucleation-doping” method. Selenium powder was directly injected into manganese precursors under high temperature, then selenium powder slowly but constantly dissolved and promoted the formation of MnSe nanocrystals with the balance of chemical reaction, which would quickly generate Mn-doped ZnSe QDs with the addition of zinc ion precursor. Compared with homogeneous Se for synthesis of Mn doped ZnSe QDs, this method can achieve fast synthesis of high quality QDs that can also be water-soluble through ligand change with mercaptopropionic acid (MPA). The obtained product was carefully charaterized, and trace impurities was analytically determined. [ABSTRACT FROM AUTHOR]

Nano-hydroxyapatite particles (Ca 10 (PO 4 ) 6 (OH) 2 , nano-HAp), the main inorganic components of human bone and teeth, has attracted much attentions as a kind of biocompatible carrier to construct dual/multi modal bioimaging probes in recent years. However, the currently developed HAp-based probes still have some shortcomings, such as poor mono-dispersion, potential toxicity and none near-infrared emission, which hinder their further applications in the field of bioimaging. In order to solve the above problems and to combine the high space resolution of CT and high sensitivity of fluorescence together, here we developed a novel dual-modal (CT/fluorescence) bioimaging probe based on nano-HAp. Ba 2 + as a CT contrast agent was doped into the lattice of nano-HAp, and Cu-doped quantum dots with near-infrared fluorescent emission and hyaluronic acid (HA) were conjugated with the HAp as a fluorescent agent and tumor-targeting ligand individually to realize its near-infrared imaging and tumor-targeting. The as-received Ba 2 + -doped HAp-QDs-HA conjugates not only well maintained the good dispersion of nano-HAp, but also possessed near-infrared emission at about 700 nm, good biocompatibility and photostability. Furthermore, the in-vitro CT and fluorescence cell imaging of the conjugates also exhibited good dual-modal bioimaging and tumor-targeting ability for potential applications in the field of early diagnosis and therapy of cancer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Focusing on the biomedical applications of nanoscale MOFs instead of the synthesis and structural properties. • Reviewing the nanoscale MOFs for disease diagnosis and treatment with emphasis on the features and practical applications. • Summarizing the schemes for designing the biological sensor and nanomedicine for practical uses related with analytical science. • Perspectives on the design of nanoscale MOFs for challenging thorny medical diagnosis and treatment. Nanoscale metal organic frameworks (nMOFs) are coordination polymers composed of organic ligands and inorganic vertices at nanometer scale. Inherent biodegradability, flexible ligands and adjustable metal centers allow nMOFs to versatile applications in biomedical care. The intensive studies have involved design and fabrication of multifunctional nMOFs and investigation of their biocompatibility effects, drug delivery ability for various diseases, especially for tumors. This article mainly summarizes and reviews the progresses on the medical and analytical applications of nMOFs in the recent decade. We provide a concise introduction to nMOFs first, and then focus on three typical categories of medical applications related with clinical disease diagnosis (biomarker detection and molecular imaging), therapy (chemotherapy, radiotherapy, phototherapy, microwave therapy, and ultrasonic therapy), and integration of both (mainly about imaging guided therapy). Each section is discussed in detail, followed by the future challenges and perspectives of nMOFs for medical diagnosis and therapy. This review may stimulate interdisciplinary research at nMOFs and clinical chemistry/medicine, which would propel nMOFs to advance into the translational medicine and clinical chemistry for practical uses. [ABSTRACT FROM AUTHOR]

Abstract: By use of the high separation capability of capillary electrophoresis (CE) and ultrasensitive chemiluminescence (CL) detection, a CE–CL method was proposed for the ultrasensitive determination of trace cobalt in a single hair, which is potentially useful in construction of the fingerprint of trace elements in the hair collected from crime scenes. In this work, the CE experimental conditions, CL experimental conditions and the digestion methods for the analysis of a single hair sample for cobalt were investigated in detail. The relative limit of detection (LOD, 3σ) was 0.01ng/mL, and the absolute LOD was 2.4×10−16 g considering the sampling volume of 24nL. Using a dry digestion method, the analytical results for certified reference hair samples by the proposed method were in good agreement with the certified values. Finally, this method was successfully used to detect trace cobalt in a single hair from three adults. It has potential applications in forensic analysis. [Copyright &y& Elsevier]

Through dispersing Co 3 O 4 into a 3D flower-like OV-HAp (Oxygen Vacancies Hydroxyapatite) support, Co 3 O 4 @OV-HAp was facilely obtained and the agglomeration of Co 3 O 4 , as well as the leaching of Co2+ were efficiently inhibited. With both PMS (peroxymonosulfate) and visible-light presented, Co 3 O 4 @OV-HAp was used as a heterogeneous catalyst for model dye Rh B (Rhodamine B) degradation in which visible-light was introduced to be another activation source for ROSs (Reactive Oxygen Species) generation except for PMS. The catalytic reaction parameters were optimized and the concentrations of Co as well as the possible co-existent metal ions were all determined by ICP-OES (inductively coupled plasma optical emission spectrometer) and ICP-MS (inductively coupled plasma mass spectrometer) individually. The synergistic effect between visible-light photo-catalysis and SO 4 •- oxidation process greatly enhanced the catalytic activity of Co 3 O 4 @OV-HAp for Rh B degradation, and 100% Rh B can be degraded compared with only 5% by Co 3 O 4. Moreover, the degradation rate was also greatly increased to about 212-fold higher in comparison with Co 3 O 4. • Co 3 O 4 @OV-HAp was facilely fabricated. • Agglomeration of Co 3 O 4 and Co2+ leaching were efficiently inhibited. • OV-HAp is not only as a support for Co 3 O 4 dispersion and immobilization but also for a heterogeneous junction. • The catalytic activities were enhanced by synergistic effect between visible-light photocatalysis and SO4•− oxidation. [ABSTRACT FROM AUTHOR]