Developing a controllable drug delivery system is imperative and important to reduce side effects and enhance the therapeutic efficacy of drugs. Metal-organic frameworks (MOFs) an emerging class of ...hybrid porous materials built from metal ions or clusters bridged by organic linkers have attracted increasing attention in the recent years owing to the unique physical structures possessed, and the potential for vast applications. The superior properties of MOFs, such as well-defined pore aperture, tailorable composition and structure, tunable size, versatile functionality, high agent loading, and improved biocompatibility, have made them promising candidates as drug delivery hosts. MOFs for drug delivery is of great interest and many very promising results have been found, indicating that these porous solids exhibit several advantages over existing systems.
This review highlights the latest advances in the synthesis, functionalization, and applications of MOFs in drug delivery, and has classified them using drug loading strategies. Finally, challenges and future perspectives in this research area are also outlined.
Photodynamic therapy (PDT) is a promising antitumor treatment that is based on the photosensitizers that inhibit cancer cells by yielding reactive oxygen species (ROS) after irradiation of light with ...specific wavelengths. As a potential photosensitizer, titanium dioxide (TiO2) exhibits minimal dark cytotoxicity and excellent ultraviolet (UV) light triggered cytotoxicity, but is challenged by the limited tissue penetration of UV light. Herein, a novel near-infrared (NIR) light activated photosensitizer for PDT based on TiO2-coated upconversion nanoparticle (UCNP) core/shell nanocomposites (UCNPs@TiO2 NCs) is designed. NaYF4:Yb3+,Tm3+@NaGdF4:Yb3+ core/shell UCNPs can efficiently convert NIR light to UV emission that matches well with the absorption of TiO2 shells. The UCNPs@TiO2 NCs endocytosed by cancer cells are able to generate intracellular ROS under NIR irradiation, decreasing the mitochondrial membrane potential to release cytochrome c into the cytosol and then activating caspase 3 to induce cancer cell apoptosis. NIR light triggered PDT of tumor-bearing mice with UCNPs@TiO2 as photosensitizers can suppress tumor growth efficiently due to the better tissue penetration than UV irradiation. On the basis of the evidence of in vitro and in vivo results, UCNPs@TiO2 NCs could serve as an effective photosensitizer for NIR light mediated PDT in antitumor therapy.
Lithium-ion power battery has become one of the main power sources for electric vehicles and hybrid electric vehicles because of superior performance compared with other power sources. In order to ...ensure the safety and improve the performance, the maximum operating temperature and local temperature difference of batteries must be maintained in an appropriate range. The effect of temperature on the capacity fade and aging are simply investigated. The electrode structure, including electrode thickness, particle size and porosity, are analyzed. It is found that all of them have significant influences on the heat generation of battery. Details of various thermal management technologies, namely air based, phase change material based, heat pipe based and liquid based, are discussed and compared from the perspective of improving the external heat dissipation. The selection of different battery thermal management(BTM) technologies should be based on the cooling demand and applications, and liquid cooling is suggested being the most suitable method for large-scale battery pack charged/discharged at higher C-rate and in high-temperature environment. The thermal safety in the respect of propagation and suppression of thermal runaway is analyzed.
•Database of two-phase frictional pressure drop in mini/micro single channels was established.•Homogenous flow and separated flow models of two-phase flow frictional pressure drop in single channels ...were reviewed.•A new correlation was proposed to predict two-phase frictional pressure drop in mini/micro single channels.
1521 frictional pressure drop data points were collected from 12 literatures. The database included adiabatic and diabatic systems composed of 10 working fluids. The diameter range was from 0.1 to 3mm, and the pressure drop ranged from 1.26kPa/m to 2MPa/m. 17 existing single channel two-phase pressure drop correlations including homogenous flow model and separated flow model were evaluated with the database. The comparison results showed that the correlations of Pamitran et al., Hwang and Kim, Mishima and Hibiki and Zhang et al. gave better predictions than the others. However, the performance evaluation results also showed the mean absolute errors higher than 40%. Based on the relatively large prediction error by the existing correlations, a new correlation was proposed by classifying the flow conditions into four regimes (namely, 1: gas laminar-liquid laminar, 2: gas laminar-liquid turbulent, 3: gas turbulent-liquid laminar, 4: gas turbulent-liquid turbulent). The newly developed correlation is expressed by a function of the two-phase Reynolds number, Retp, the two-phase viscosity number, Nμtp, and the gas quality, x, and was able to predict the two-phase frictional pressure drop with the mean absolute percentage error of 17.4%. The correlation demonstrated an excellent performance for predicting the two-phase frictional pressure drop in mini/micro single channels.
As sensors, wireless communication devices, personal health monitoring systems, and autonomous microelectromechanical systems (MEMS) become distributed and smaller, there is an increasing demand for ...miniaturized integrated power sources. Although thin-film batteries are well-suited for on-chip integration, their energy and power per unit area are limited. Three-dimensional electrode designs have potential to offer much greater power and energy per unit area; however, efforts to date to realize 3D microbatteries have led to prototypes with solid electrodes (and therefore low power) or mesostructured electrodes not compatible with manufacturing or on-chip integration. Here, we demonstrate an on-chip compatible method to fabricate high energy density (6.5 μWh cm ⁻²⋅μm ⁻¹) 3D mesostructured Li-ion microbatteries based on LiMnO ₂ cathodes, and NiSn anodes that possess supercapacitor-like power (3,600 μW cm ⁻²⋅μm ⁻¹ peak). The mesostructured electrodes are fabricated by combining 3D holographic lithography with conventional photolithography, enabling deterministic control of both the internal electrode mesostructure and the spatial distribution of the electrodes on the substrate. The resultant full cells exhibit impressive performances, for example a conventional light-emitting diode (LED) is driven with a 500-μA peak current (600-C discharge) from a 10-μm-thick microbattery with an area of 4 mm ² for 200 cycles with only 12% capacity fade. A combined experimental and modeling study where the structural parameters of the battery are modulated illustrates the unique design flexibility enabled by 3D holographic lithography and provides guidance for optimization for a given application.
Significance Microscale batteries can deliver energy at the actual point of energy usage, providing capabilities for miniaturizing electronic devices and enhancing their performance. Here, we demonstrate a high-performance microbattery suitable for large-scale on-chip integration with both microelectromechanical and complementary metal-oxide–semiconductor (CMOS) devices. Enabled by a 3D holographic patterning technique, the battery possesses well-defined, periodically mesostructured porous electrodes. Such battery architectures offer both high energy and high power, and the 3D holographic patterning technique offers exceptional control of the electrode’s structural parameters, enabling customized energy and power for specific applications.
•HIIT enhanced the autophagy activity in the brain of T2DM model mice.•HIIT and MICT improved learning and memory ability of T2DM mice model.
Exercise can improve cognitive impairment in type 2 ...diabetes mellitus (T2DM). However, the underlying mechanisms are not clear, and the optimal exercise modes for cognitive benefits are controversial. The aim of this study was to investigate the effects of high-intensity interval training (HIIT) and moderate-intensity interval training (MICT) on cognitive function and the PI3K/Akt/mTOR pathway as well as autophagy in T2DM mice. The results showed that 8 weeks of HIIT and MICT intervention could improve the spatial learning and memory ability of T2DM mice, as determined by the Morris water maze (MWM) test. Both HIIT and MICT similarly improved autophagy, as evidenced by increased Beclin1 and LC3 II/I ratios and decreased p62. Meanwhile, HIIT and MICT inhibited excessive activation of the PI3K/Akt/mTOR pathway in the hippocampus. HIIT induced a larger reduction in mTOR activity than MICT. This study suggests that both HIIT and MICT can alleviate cognitive decline induced by T2DM, improve autophagy in the hippocampus, and downregulate the excessive activation of the PI3K/Akt/mTOR signaling pathway, with similar effects.
To overcome the side effects of and resistance to cisplatin, a variety of Pt(IV) prodrugs were designed and synthesized via different modifications including combination with lipid chains to increase ...hydrophobicity, conjugation with short peptide chains or nanoparticles to improve drug delivery, or addition of bioactive ligands to the axial positions of Pt(IV) complexes to exert dual-function effects. This review summarizes the recent progress in the development of Pt(IV) prodrugs conjugated with bioactive-targeting ligands, including histone deacetylase inhibitors, p53 agonists, alkylating agents, and nonsteroidal anti-inflammatory agents. Although Pt(IV) complexes that conjugated with bioactive ligands show satisfactory anticancer effects, none has been approved for clinical use. Therefore, we hope that this review will contribute to further study and development of Pt(IV) complexes conjugated with bioactive and other ligands.
T oilfield is the fractured-vuggy carbonate reservoir at a temperature of around 130 °C, with salinity of up to 22 × 104 mg/L. In order to solve the problem of the high water cut in the late ...development stage of T oilfield, we selected XN-T from 27 kinds of swelling retarding particles by testing their swelling capacity, and coated a thin film to improve its retarding swelling capacity. The mechanisms of strong water absorption and water-holding abilities of particles were analyzed by infrared spectrometry and SEM. In the core flow experiment, the plugging rate was found to be 98.42%. Finally, the injection parameters of the coated particles were optimized to maximize the water plugging and profile control ability, resulting in an optimal particle size of 0.4–0.6 mm and a mass fraction of 10%.
Display omitted
•Notable levels of OPA and NOPE were found in e-waste dismantling workers’ hands for the first time.•The levels of NOPE were higher than those of traditional OPE on workers’ ...hands.•The dust levels of TPHP and AO168 = O might be acceptable predictors of hand wipe levels.•Occupational exposure to NOPE via hand-to-mouth contact was more significant than dust ingestion.
Electronic waste (e-waste) is a well-known source of plastic additives in the environment. However, the e-waste-related occupational exposure to organophosphite antioxidants (OPAs) and the relevant oxidation products—novel organophosphate esters (NOPEs)—via different pathways is still unknown. In this study, six OPAs and three NOPEs were measured in 116 dust and 43 hand-wipe samples from an e-waste dismantling area in Central China. The median concentrations of ΣOPAs and ΣNOPEs were 188 and 13,900 ng·g−1 in workshop dust and 5,250 ng·m−2 and 53,600 ng·m−2 on workers’ hands, respectively. The increasing concentrations of dust in the form of triphenyl phosphate (TPHP) (p < 0.01) and tris(2,4-di-tert-butylphenyl) phosphate (AO168 = O) (p < 0.05) were strongly associated with the corresponding concentration on workers’ hands. Furthermore, men had significantly lower levels of NOPEs on their hands than did women (p < 0.01). Moreover, the hand wipe levels of AO168 = O (41,600 ng·m−2) was significantly higher than that of the typical OPE (TPHP, 7370 ng·m−2), and the hand-to-mouth contact (ΣOPAs, 9.48 ng·kg bw-1·day−1; ΣNOPEs, 109 ng·kg bw-1·day−1) was a more significant and integrated pathway than dust ingestion (ΣOPAs, 0.10 ng·kg bw-1·day−1; ΣNOPEs, 5.01 ng·kg bw-1·day−1) of e-waste related occupational exposure to these “new” chemicals.
Up‐conversion (UC) luminescent and porous NaYF4:Yb3+, Er3+@SiO2 nanocomposite fibers are prepared by electrospinning process. The biocompatibility test on L929 fibrolast cells reveals low ...cytotoxicity of the fibers. The obtained fibers can be used as anti‐cancer drug delivery host carriers for investigation of the drug storage/release properties. Doxorubicin hydrochloride (DOX), a typical anticancer drug, is introduced into NaYF4:Yb3+, Er3+@SiO2 nanocomposite fibers (denoted as DOX‐NaYF4:Yb3+, Er3+@SiO2). The release properties of the drug carrier system are examined and the in vitro cytotoxicity and cell uptake behavior of these NaYF4:Yb3+, Er3+@SiO2 for HeLa cells are evaluated. The release of DOX from NaYF4:Yb3+, Er3+@SiO2 exhibits sustained, pH‐sensitive release patterns and the DOX‐NaYF4:Yb3+, Er3+@SiO2 show similar cytotoxicity as the free DOX on HeLa cells. Confocal microscopy observations show that the composites can be effectively taken up by HeLa cells. Furthermore, the fibers show near‐infrared UC luminescence and are successfully applied in bioimaging of HeLa cells. The results indicate the promise of using NaYF4:Yb3+, Er3+@SiO2 nanocomposite fibers as multi‐functional drug carriers for drug delivery and cell imaging.
NaYF4:Yb3+, Er3+@SiO2 nanocomposite fibers, which are used as a novel anticancer drug carrier, are prepared using an electrospinning process. The fibers show the attractive properties of regular morphology, porous structure, good biocompatibility, and up‐conversion emission. The drug loading and release properties, cytotoxicity, cellular uptake, and cell imaging of nanocomposite fibers are investigated.