Advances in inorganic nanoparticles trapping stiffness measurement:A promising tool for energy and environmental study

Optical tweezers system has emerged as an efficient tool to manipulate tiny particles in a non-invasive way.Trapping stiffness,as an essential parameter of an optical potential well,represents the trapping stability.Additionally,trapping inorganic nanoparticles such as metallic nanoparticles or other functionalized inorganic nanoparticles is important due to their properties of good stability,high conductivity,tolerable toxicity,etc.,which makes it an ideal detection strategy for bio-sensing,force calculation,and determination of particle and environmental properties.However,the trapping stiffness measurement(TSM)methods of inorganic nanoparticles have rarely been analyzed and summarized.Here,in this review,the principle and methods of TSM are analyzed.We also systematically summarize the progress in acquiring inorganic particles trapping stiffness and its promising applications.In addition,we provide prospects of the energy and environment applications of optical tweezering technique and TSM.Finally,the challenges and future directions of achieving the nanoparticles trapping stiffness are discussed.

Inorganic nanoparticles and the microbiome

Routine exposure to inorganic nanoparticles （NPs） that are incorporated into consumer products such as foods/drinks, packaging materials, pharmaceuticals, and personal care products （e.g. cosmetics, sunscreens, shampoos） occurs on a daily basis. The standard everyday use of these products facilitates interactions between the incorporated inorganic NPs, mammalian tissues （e.g. skin, gastrointestinal tract, oral cavity）, and the community of microbes that resides on these tissues. Changes to the microbiome have been linked to the initiation/ progression of many diseases and there is a growing interest focused on understanding how inorganic NPs can initiate these changes. As these mechanisms are revealed and defined, it may be possible to rationally design microbiota- modulating therapies based on inorganic NPs. In this article, we will： （i） provide a background on inorganic NPs that are commonly found in consumer products such as those that incorporate titanium, zinc, silver, silica, or iron, （ii） discuss how NP properties, microbiota composition, and the physiological microenvironment can mediate the effects that inorganic NPs have on the microbiota, and （iii） highlight opportunities for inorganic NP therapies that are designed to interact with, and navigate, the microbiome.

Ultrastructure Changes and Mechanism of Cancer Cells Induced by Inorganic Crystal Nanoparticles

The purpose of this study was to examine the changes of cancer cell in ultrastructure after inorganic crystal nanoparticles （ICN） absorption. HAP and TiO2 nanoparticles were incubated with the Bet- 7402 cells for 1 h and 8 h respectively. Then, cancer cells were collected and examined under transmission electron microscope （TEM）. In cytoplasm, nanoparticle were contained in some vacuoles. Some death features of cell appear. The experimental results indicated that ICN can induce cancer cells death.

Fabrication of gold nanoparticles with different morphologies in HEPES buffer

Gold nanoparticles with different morphologies, such as spindle, octahedron, and decahedron were obtained by using different molar ratios of HAuCl4/HEPES in the presence and absence of surfactants at room temperature.These nanoparticles were characterized by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, high-resolution transmission electron microscopy（HRTEM）, scanning electron microcopy（SEM）, energy-dispersive X-rays analysis（EDX）, and selected area electron diffraction（SAED）.The kinetics of the formation of gold nanoparticles in HEPES buffer was studied by UV-visible spectrophotometer.The formation of gold nanoparticles was strongly dependent on the concentration of HEPES and pH value.The surfactants play a crucial role in the size and shape controlled synthesis of gold nanoparticles.

Recent advances in nanotherapeutics for the treatment and prevention of acute kidney injury

Acute kidney injury(AKI)is a serious kidney disease without specific medications currently except for expensive dialysis treatment.Some potential drugs are limited due to their high hydrophobicity,poor in vivo stability,low bioavailability and possible adverse effects.Besides,kidney-targeted drugs are not common and small molecules are cleared too quickly to achieve effective drug concentrations in injured kidneys.These problems limit the development of pharmacological therapy for AKI.Nanotherapeutics based on nanotechnology have been proved to be an emerging and promising treatment strategy for AKI,which may solve the pharmacological therapy dilemma.More and more nanotherapeutics with different physicochemical properties are developed to efficiently deliver drugs,increase accumulation and control release of drugs in injury kidneys and also directly as effective antioxidants.Here,we discuss the recent nanotherapeutics applied in the treatment and prevention of AKI with improved effectiveness and few side effects.

一种通用静电组装策略用于印刷无机纳米颗粒及其在大面积钙钛矿太阳电池中的应用

无机纳米颗粒作为一种极具前景的材料,在钙钛矿太阳电池的传输层中得到了广泛应用.然而,无机纳米颗粒易于聚集的特性阻碍了其进一步的发展.在大面积制备过程中,无机纳米颗粒的聚集加剧了“咖啡环效应”,导致薄膜不均匀,使得底部界面性能较差,进而影响钙钛矿薄膜的结晶,最终导致整个器件性能下降.为解决这一问题,我们将一种带电聚合物一一聚乙烯亚胺引入至无机纳米颗粒溶液中.聚乙烯亚胺的带电性质对无机纳米颗粒的聚集起到了显著的抑制作用,此外,添加聚乙烯亚胺还增加了无机纳米颗粒溶液的粘度,有助于减少薄膜上的负面咖啡环效应.最终,我们在基于1-cm^(2)正式结构且使用SnO_(2)传输层的器件上实现了23.2%的光电转换效率.为进一步证明这一策略的普适性,我们还将此策略验证基于NiO_(x)传输层的1-cm^(2)反式器件,其转换效率超过20%.

Mesoporous PtPd nanoparticles for ligand-mediated and imaging-guided chemo-photothermal therapy of breast cancer

The synergistic therapy of chemotherapy and photothermal therapy(PTT)has been reported as a promising antitumor strategy.To achieve effective combination therapy,developing more suitable candidate nanomaterials with optimal photothermal property and high chemical drug loading capacity is very necessary.Herein,a bimetallic PtPd nanoparticle was synthesized with the merits of excellent photothermal effect and mesoporous structure for doxorubicin(DOX)loading.We further designed PtPd-ethylene glycol(PEG)-folic acid(FA)-doxorubicin(DOX)nanoparticle for chemo-photothermal therapy of MCF-7 tumor with folic acid engineering to achieve active targeting.Moreover,excellent photoacoustic(PA)imaging of PtPd-PEG-FA-DOX nanoparticles facilitated the precise in vivo tracking and further evaluation of nanoparticles’targeting effect.The in vitro and in vivo results both demonstrated PtPd-PEG-FA-DOX nanoparticles serve as a safe and promising system for effective treatment of MCF-7 tumor.

Recent advances in novel aerogels through the hybrid aggregation of inorganic nanomaterials and polymeric fibers for thermal insulation

Aerogel is a nanoporous solid material with ultrahigh porosity,ultralow density,and thermal conductivity,which is considered to be one of the most promising high-performance insulation materials today.However,traditional pure inorganic aerogels(i.e.,silica aerogel)exhibit inherent structural brittleness,making their processing and handling difficult,and their manufacturing costs are relatively high,which limits their large-scale practical use.The recently developed aerogel based on polymer nanofibers has ultralow thermal conductivity and density,excellent elasticity,and designable multifunction.More importantly,one-dimensional polymer nanofibers are directly used as building blocks to construct the network of aerogels via a gelation-free process.This greatly simplifies the aerogel preparation process,thereby bringing opportunities for large-scale aerogel applications.The aggregation of inorganic nanomaterials and polymer nanofibers is considered to be a very attractive strategy for obtaining highly flexible,easily available,and multifunctional composite aerogels.Therefore,this review summarizes the recent advances in novel aerogels through the hybrid aggregation of inorganic nanomaterials and polymeric fibers for thermal insulation.The main processing routes,porous microstructure,mechanical properties,and thermal properties and applications of these aerogels are highlighted.In addition,various future challenges faced by these aerogels in thermal insulation applications are discussed in this review.

Construction of smart inorganic nanoparticle-based ultrasound contrast agents and their biomedical applications

Ultrasound(US) imaging in combination with US contrast agents(UCAs) is a powerful tool in the modern biomedical field because of its high spatial resolution, easy access to patients and minimum invasiveness.The microbubble-based UCAs have been widely used in clinical diagnosis; however, they are only limited to the blood pool imaging and not applicable to the tissue-penetrated imaging due to their large particle size and structural instability. Inorganic nanoparticles(NPs), such as silica,gold and Fe x O y, featured with both satisfactory echogenic properties and structural stability have the potential to be used as a new generation of UCAs. In this review, we present the most recent progresses in the tailored construction of inorganic UCAs and their biomedical applications in the US imaging-involved fields. Firstly, the typical inorganic NPs with different structures including solid, hollow and multiple-layer forms will be comprehensively introduced in terms of their structure design,physicochemical property, US imaging mechanism and diverse applications; secondly, the recent progress in exploring the gas-generating inorganic NP system for US imaging purpose will be reviewed, and these intelligent UCAs are multifunctional for simultaneous US imaging and disease therapy; thirdly, several nanocomposite platforms newly constructed by combining inorganic UCAs with other functional components will be presented anddiscussed. These multifunctional NPs are capable of further enhancing the imaging resolution by providing more comprehensive anatomical information simultaneously.Last but not the least, the design criteria for developing promising UCAs to satisfy both clinical demands and optimized US imaging capability will be discussed and summarized in this review.

Inorganic Nanotube/Organic Nanoparticle Hybrids for Enhanced Photoelectrochemical Properties

Inorganic/organic nanohybrids composed of arrayed TiO_2 nanotubes（Ti NTs）/porphyrin nanoparticles（NPs） have been fabricated via a wet chemical approach. The inorganic component, particularly the arrayed one-dimensional（1D） nanostructures, provides high charge-carrier mobility and rapid charge transport. The organic component exhibits extensive visible light absorption and good solution processability. Additionally, the geometric restraint by supramolecular assembly renders an improved photostability. A combination of these two components could thus allow for an efficient solar energy conversion. In this work, a colloid of porphyrin NPs prepared by a solvent exchange method is coated on anodic Ti NTs by means of a dip-coating treatment to form inorganic/organic hybrids. The hybrids exhibit an improvement on solar absorption and a significant enhancement on photocurrent generation at a small bias compared with individual component. Herein, the inorganic/organic nanohybrids are proved to be excellent photoanodes highly responsive to visible light and thus pave a way to discover new inorganic/organic assemblies for high-performance optoelectronic applications, as well as for device integration.

Strategies to assemble therapeutic and imaging molecules into inorganic nanocarriers

Inorganic nanocarriers are potent candidates for delivering conventional anticancer drugs,nucleic acid-based therapeutics,and imaging agents,influencing their blood half-lives,tumor targetability,and bioactivity.In addition to the high surface area-to-volume ratio,they exhibit excellent scalability in synthesis,controllable shape and size,facile surface modification,inertness,stability,and unique optical and magnetic properties.However,only a limited number of inorganic nanocarriers have been so far approved for clinical applications due to burst drug release,poor target specificity,and toxicity.To overcome these barriers,understanding the principles involved in loading therapeutic and imaging molecules into these nanoparticles(NPs)and the strategies employed in enhancing sustainability and targetability of the resultant complexes and ensuring the release of the payloads in extracellular and intracellular compartments of the target site is of paramount importance.Therefore,we will shed light on various loading mechanisms harnessed for different inorganic NPs,particularly involving physical entrapment into porous/hollow nanostructures,ionic interactions with native and surface-modified NPs,covalent bonding to surface-functionalized nanomaterials,hydrophobic binding,affinity-based interactions,and intercalation through co-precipitation or anion exchange reaction.

具有红色上转换发光和近红外二区发光的生物可降解镧系掺杂无机纳米颗粒用于生物成像和光动力治疗

近红外二区镧掺杂无机纳米颗粒由于其较低的光子散射和较弱的自身荧光特性而受到广泛关注.然而,这些纳米颗粒具有“刚性”和生理惰性的晶格结构(例如NaYF_(4):Yb,Er),无法在体内降解,限制了它们在生物医学上的进一步应用.改变化学结构,实现晶体由“刚性”向“软性”的转变,是一种促进其可降解生物应用的可行方法.在这里,我们报道了一种可生物降解的近红外二区镧掺杂无机纳米颗粒Na_(3)ZrF_(7):Yb,Er,Ce(NZF).通过Na的调控和Ce^(3+)的掺杂优化,NZF纳米粒子的近红外二区下转换发光强度比Na_(3)ZrF_(7):Yb,Er提高了约37倍.由于其“软”的晶格特征,水可以破坏其晶体结构,降解产物可以从器官和组织中排出.此外,NZF还表现出红色的上转换发光能力.在表面改性后,我们基于其近红外二区的下转换发光和红色上转换发光的特性进行了可降解生物成像应用和光动力治疗的概念验证,这些发现将有利于稀土掺杂无机纳米颗粒的未来生物医学应用.

Inhibitory activity of gold and silica nanospheres to vascular endothelial growth factor （VEGF）-mediated angiogenesis is determined by their sizes

Nanoparticles can be involved in biological activities such as apoptosis, angiogenesis, and oxidative stress by themselves. In particular, inorganic nanoparticles such as gold and silica nanoparticles are known to inhibit vascular endothelial growth factor （VEGF）-mediated pathological angiogenesis. In this study, we show that anti-angiogenic effect of inorganic nanospheres is determined by their sizes. We demonstrate that 20 nm size gold and silica nanospheres suppress VEGF-induced activation of VEGF receptor-2, in vitro angiogenesis, and in vivo pathological angiogenesis more efficiently than their 100 nm size counterparts. Our results suggest that modulation of the size of gold and silica nanospheres determines their inhibitory activity to VEGF-mediated angiogenesis.

Hybrid Janus Nanotubes with Tunable Internal Pore Size Disassembled from Mesoporous Block Copolymer-based Hybrid Scaffolds

The hybrid Janus nanomaterials have captured considerable attention since the asymmetric structure can combine the properties of each component and display synergistic applications.However,the precise design of the specific hybrid Janus nanostructures still remains a formidable challenge.Here,we for the first time report the fabrication of novel and highly uniform inorganic/organic hybrid Janus nanotubes via disassembling the mesoporous inorganic nanoparticles(NPs)/polystyrene-block-poly(4-vinylpyridine)(PS-b-P4VP)hybrid sheets,which are generated through the in situ reduction of functional metal precursors on the prepared PS-b-P4VP mesoporous scaffolds.More importantly,the internal pore size of the hybrid Janus nanotubes can be precisely tuned by readily controlling the swelling time of the PS-b-P4VP sheet-like assemblies in a selective solvent for P4VP domains,thus generating the particular inorganic/organic hybrid Janus nanotubes with adjustable inner diameter size.We believe that our finding will provide an efficient and universal route to fabricate the particular inorganic/organic hybrid nanotubes for hierarchical functional devices and nanomaterials.