ZnO nanoparticles applied to bioimaging and drug delivery

Insight into the origin of ferromagnetism in Fe-doped ZnO diluted magnetic semiconductor nanocrystals: an EXFAS study of local structure

XANES study at Fe edge (a) and signature of ferromagnetism (b) of Zn_1−xFe_xO nanoparticles.

Extracellularly synthesized ZnO nanoparticles interact with DNA and augment gamma radiation induced DNA damage through reactive oxygen species

ZnONPs were synthesized using ferulic acid as the reductant and the intricate twofold role as DNA binders and radio sensitizers was revealed, which can pave the way for anticancer therapy.

Green synthesis of zinc oxide nanoparticles using Hibiscus subdariffa leaf extract: effect of temperature on synthesis, anti-bacterial activity and anti-diabetic activity

Particle size dependent anti-bacterial and anti-diabetic activities of green synthesized ZnO nanoparticles.

Facile synthesis of core/shell ZnO/ZnS nanofibers by electrospinning and gas-phase sulfidation for biosensor applications

This study describes a new method of passivating ZnO nanofiber-based devices with a ZnS layer.

Direct observation of key photoinduced dynamics in a potential nano-delivery vehicle of cancer drugs

The crucial photoinduced dynamics in ZnO nanoparticles (NPs) upon complexation with the cancer drug protoporphyrin IX (PP).

Lethal photosensitisation of Staphylococcus aureus and Escherichia coli using crystal violet and zinc oxide-encapsulated polyurethane

Bactericidal polymer surfaces were prepared by crystal violet and ZnO nanoparticle encapsulation, demonstrating 99.9% dark kill ofE. coli.

Surface modified Mg-doped ZnO QDs for biological imaging

Nanocrystals of ZnO are currently attracting great interest as potential labels for biological applications, such as theranostic devices, due to their luminescent properties and low toxicity in vivo. It has been reported that doping with Mg

Controllable synthesis and change of emission color from green to orange of ZnO quantum dots using different solvents

ZnO quantum dots, a few nanometers in size, exhibited strong visible emission from green to orange, resulting from the quantum size effect and the change in defect concentration due to the different solvents used for preparation.

Lipid-coated ZnO nanoparticles as lymphatic-targeted drug carriers: study on cell-specific toxicity in vitro and lymphatic targeting in vivo

Lipid coated ZnO nanoparticles (LZnO NPs) were developed as a novel lymphatic drug delivery system. High lymphotropism and tumour cells selective toxicity ensure the nanoparticles being a promising candidate for treatment of tumor metastasis.

The potential of magneto-electric nanocarriers for drug delivery

INTRODUCTION

The development and design of personalized nanomedicine for better health quality is receiving great attention. In order to deliver and release a therapeutic concentration at the target site, novel nanocarriers (NCs) were designed, for example, magneto-electric (ME) which possess ideal properties of high drug loading, site-specificity and precise on-demand controlled drug delivery.

AREAS COVERED

This review explores the potential of ME-NCs for on-demand and site-specific drug delivery and release for personalized therapeutics. The main features including effect of magnetism, improvement in drug loading, drug transport across blood-brain barriers and on-demand controlled release are also discussed. The future directions and possible impacts on upcoming nanomedicine are highlighted.

EXPERT OPINION

Numerous reports suggest that there is an urgent need to explore novel NC formulations for safe and targeted drug delivery and release at specific disease sites. The challenges of formulation lie in the development of NCs that improve biocompatibility and surface modifications for optimum drug loading/preservation/transmigration and tailoring of electrical-magnetic properties for on-demand drug release. Thus, the development of novel NCs is anticipated to overcome the problems of targeted delivery of therapeutic agents with desired precision that may lead to better patient compliance.

Multifunctional enveloped mesoporous silica nanoparticles for subcellular co-delivery of drug and therapeutic peptide

A multifunctional enveloped nanodevice based on mesoporous silica nanoparticle (MSN) was delicately designed for subcellular co-delivery of drug and therapeutic peptide to tumor cells. Mesoporous silica MCM-41 nanoparticles were used as the core for loading antineoplastic drug topotecan (TPT). The surface of nanoparticles was decorated with mitochondria-targeted therapeutic agent (Tpep) containing triphenylphosphonium (TPP) and antibiotic peptide (KLAKLAK)2 via disulfide linkage, followed by coating with a charge reversal polyanion poly(ethylene glycol)-blocked-2,3-dimethylmaleic anhydride-modified poly(L-lysine) (PEG-PLL(DMA)) via electrostatic interaction. It was found that the outer shielding layer could be removed at acidic tumor microenvironment due to the degradation of DMA blocks and the cellular uptake was significantly enhanced by the formation of cationic nanoparticles. After endocytosis, due to the cleavage of disulfide bonds in the presence of intracellular glutathione (GSH), pharmacological agents (Tpep and TPT) could be released from the nanoparticles and subsequently induce specific damage of tumor cell mitochondria and nucleus respectively with remarkable synergistic antitumor effect.

Monodisperse lanthanide oxyfluorides LnOF (Ln = Y, La, Pr-Tm): morphology controlled synthesis, up-conversion luminescence and in vitro cell imaging

Lanthanide oxyfluorides LnOF (Ln = Y, La, Pr-Tm) nano/micro-materials with a variety of well-defined morphologies including nanorods, nanospindles, nanorod-bundles and nanospheres, have been successfully synthesized via a facile precipitation technique followed by a heating treatment. It is found that the pH values, fluoride sources and dosage of urea in the initial reaction systems play critical roles in the morphology determination of the LnOF products and the possible formation mechanism for these diverse architectures has been presented. XRD, FT-IR, TG-DTA, SEM, TEM, as well as up-conversion (UC) luminescence spectra are used to characterize the synthesized samples. Under 980 nm NIR laser excitation, red, green and blue UC luminescence are observed from Yb(3+)/Er(3+), Yb(3+)/Ho(3+) and Yb(3+)/Tm(3+) co-doped YOF nanospheres. The MTT assay indicates that YOF nanospheres exhibit good biocompatibility. Especially, the emission spectrum of YOF: 0.20Yb(3+), 0.04Er(3+) nanospheres is dominated by a single red emission at 660 nm, which falls into the "optical window" of biological tissues. The application of YOF: 0.20Yb(3+), 0.04Er(3+) nanospheres in the cell imaging is also investigated, which shows a bright-red emission without background noise.

Cytocompatibility evaluation of gum Arabic-coated ultra-pure boron nitride nanotubes on human cells

Aim: Boron nitride nanotubes (BNNTs) are tubular nanoparticles with a structure analogous to that of carbon nanotubes, but with B and N atoms that completely replace the C atoms. Many favorable results indicate BNNTs as safe nanomaterials; however, important concerns have recently been raised about ultra-pure, long (˜10 µm) BNNTs tested on several cell types. Materials & methods: Here, we propose additional experiments with the same BNNTs, but shortened (˜1.5 µm) with a homogenization/sonication treatment that allows for their dispersion in gum Arabic aqueous solutions. Obtained BNNTs are tested on human endothelial and neuron-like cells with several independent biocompatibility assays. Moreover, for the first time, their strong sum-frequency generation signal is exploited to assess the cellular uptake. Results & conclusion: Our data demonstrate no toxic effects up to concentrations of 20 µg/ml, once more confirming biosafety of BNNTs, and again highlighting that nanoparticle aspect ratio plays a key role in the biocompatibility evaluation.

Original submitted 3 December 2013; Revised submitted 28 January 2014; Published online 6 February 2014