PLGA Nanoparticles Formulations Loaded With Antibiotics Induce Sustained and Controlled Antibiotics Release for Prolonged Antibacterial Action Against MRSA, and Pseudomonas aeruginosa FRD1.

The purpose of the present study was to create resorbable nanoparticles (NPs) using poly(lactic-co-glycolic acid) (PLGA) to develop novel antibacterial therapeutics for the treatment of chronic wound infections that are susceptible to recurrent infections. By first performing a release study, it was possible to predict the behavior of the different PLGA NP formulations and assess the efficacy of the nanocomposite drug delivery system. These PLGA NP formulations consisted of varying ratios of PLGA without polyvinyl alcohol (PVA) and PLGA with PVA (PLGA-PVA) (i.

Antimicrobial peptide-conjugated phage-mimicking nanoparticles exhibit potent bactericidal action against in murine wound infection models.

is a causative agent for strep throat, impetigo, and more invasive diseases. The main reason for the treatment failure of streptococcal infections is increased antibiotic resistance. In recent years, infectious diseases caused by pyogenic streptococci resistant to multiple antibiotics have been rising with a significant impact on public health and the veterinary industry.

Biocompatible, Multi-Mode, Fluorescent, MRI Contrast Magnetoelectric-Silica Nanoparticles (MagSiNs), for On-Demand Doxorubicin Delivery to Metastatic Cancer Cells.

There is a need to improve current cancer treatment regimens to reduce systemic toxicity, to positively impact the quality-of-life post-treatment. We hypothesized the negation of off-target toxicity of anthracyclines (e.g.

Engineering bioactive nanoparticles to rejuvenate vascular progenitor cells.

Fetal exposure to gestational diabetes mellitus (GDM) predisposes children to future health complications including type-2 diabetes mellitus, hypertension, and cardiovascular disease. A key mechanism by which these complications occur is through stress-induced dysfunction of endothelial progenitor cells (EPCs), including endothelial colony-forming cells (ECFCs). Although several approaches have been previously explored to restore endothelial function, their widespread adoption remains tampered by systemic side effects of adjuvant drugs and unintended immune response of gene therapies.

Colloidal stability, cytotoxicity, and cellular uptake of HfO nanoparticles.

The colloidal stability, cytotoxicity, and cellular uptake of hafnium oxide (HfO ) nanoparticles (NPs) were investigated in vitro to assess safety and efficacy for use as a deliverable theranostic in nanomedicine. Monoclinic HfO NPs, ~60-90 nm in diameter and ellipsoidal in shape, were directly prepared without calcination by a hydrothermal synthesis at 83% yield. The as-prepared, bare HfO NPs exhibited colloidal stability in cell culture media for at least 10 days without significant agglomeration or settling.

Phage-mimicking antibacterial core-shell nanoparticles.

The increasing frequency of nosocomial infections caused by antibiotic-resistant microorganisms concurrent with the stagnant discovery of new classes of antibiotics has made the development of new antibacterial agents a critical priority. Our approach is an antibiotic-free strategy drawing inspiration from bacteriophages to combat antibiotic-resistant bacteria. We developed a nanoparticle-based antibacterial system that structurally mimics the protein-turret distribution on the head structure of certain bacteriophages and explored a combination of different materials arranged hierarchically to inhibit bacterial growth and ultimately kill pathogenic bacteria.

Super-resolution fluorescence microscopy by stepwise optical saturation.

Super-resolution fluorescence microscopy is an important tool in biomedical research for its ability to discern features smaller than the diffraction limit. However, due to its difficult implementation and high cost, the super-resolution microscopy is not feasible in many applications. In this paper, we propose and demonstrate a saturation-based super-resolution fluorescence microscopy technique that can be easily implemented and requires neither additional hardware nor complex post-processing.

CD133 Promotes Adhesion to the Ovarian Cancer Metastatic Niche.

Cancer stem cells (CSCs) are an attractive therapeutic target due to their predicted role in both metastasis and chemoresistance. One of the most commonly agreed on markers for ovarian CSCs is the cell surface protein CD133. CD133+ ovarian CSCs have increased tumorigenicity, resistance to chemotherapy, and increased metastasis.

Single Nanoparticle Plasmonic Spectroscopy for Study of Charge-Dependent Efflux Function of Multidrug ABC Transporters of Single Live Cells.

Multidrug membrane transporters can selectively extrude a wide variety of structurally and functionally unrelated substrates, and they are responsible for ineffective treatment of a wide range of diseases (e.g., infection and cancer).

Single Nanoparticle Plasmonic Spectroscopy for Study of the Efflux Function of Multidrug ABC Membrane Transporters of Single Live Cells.

ATP-binding cassette (ABC) membrane transporters exist in all living organisms and play key roles in a wide range of cellular and physiological functions. The ABC transporters can selectively extrude a wide variety of structurally and functionally unrelated substrates, leading to multidrug resistance. Despite extensive study, their efflux molecular mechanisms remain elusive.

Preparation of fluorescent Au-SiO core-shell nanoparticles and nanorods with tunable silica shell thickness and surface modification for immunotargeting.

Gold-silica (Au-SiO) core-shell nanoparticles (NPs) enable multifunctional properties for in vivo biomedical applications. However, scalable synthesis methods are lacking for the preparation of Au-SiO core-shell NPs less than 30 nm in overall diameter with a tunable silica shell less than 10 nm in thickness. Therefore, we prepared monodispersed Au-SiO core-shell NPs less than 30 nm in overall diameter with a uniform, tunable silica shell ∼1 to 14 nm in thickness using either citrate reduction followed by a modified Stöber method or oleylamine reduction followed by a reverse microemulsion method.

Hafnia (HfO2) nanoparticles as an X-ray contrast agent and mid-infrared biosensor.

The interaction of hafnium oxide (HfO2) nanoparticles (NPs) with X-ray and mid-infrared radiation was investigated to assess the potential as a multifunctional diagnostic probe for X-ray computed tomography (CT) and/or mid-infrared biosensing. HfO2 NPs of controlled size were prepared by a sol-gel process and surface functionalized with polyvinylpyrrolidone, resulting in relatively spherical and monodispersed NPs with a tunable mean diameter in the range of ∼7-31 nm. The X-ray attenuation of HfO2 NPs was measured over 0.

Wavelength dependent specific plasmon resonance coupling of single silver nanoparticles with EGFP.

Noble metal nanoparticles (NPs) possess unique plasmonic properties, enabling them to serve as sub-diffraction light sources and nano- antennae for a wide range of applications. Here we report the specific interaction of single Ag NPs with single EGFP molecules and a high dependence of their interaction upon localized-surface-plasmon-resonance (LSPR) spectra of single Ag NPs and EGFP. The LSPR spectra of single red Ag NPs show a stunning 60 nm blue-shift during their incubation with EGFP, whereas they remain unchanged during their incubation with bovine serum albumin (BSA).

New surface radiolabeling schemes of super paramagnetic iron oxide nanoparticles (SPIONs) for biodistribution studies.

Nanomaterial based drug delivery systems allow for the independent tuning of the surface chemical and physical properties that affect their biodistribution in vivo and the therapeutic payloads that they are intended to deliver. Additionally, the added therapeutic and diagnostic value of their inherent material properties often provides extra functionality. Iron based nanomaterials with their magnetic properties and easily tailorable surface chemistry are of particular interest as model systems.

Silver nanoparticles induce developmental stage-specific embryonic phenotypes in zebrafish.

Much is anticipated from the development and deployment of nanomaterials in biological organisms, but concerns remain regarding their biocompatibility and target specificity. Here we report our study of the transport, biocompatibility and toxicity of purified and stable silver nanoparticles (Ag NPs, 13.1 ± 2.

Volume labeling with Alexa Fluor dyes and surface functionalization of highly sensitive fluorescent silica (SiO2) nanoparticles.

A new synthesis approach is described that allows the direct incorporation of fluorescent labels into the volume or body of SiO2 nanoparticles. In this process, fluorescent Alexa Fluor dyes with different emission wavelengths were covalently incorporated into the SiO2 nanoparticles during their formation by the hydrolysis of tetraethoxysilane. The dye molecules were homogeneously distributed throughout the SiO2 nanoparticles.

Silver nanoparticles incite size- and dose-dependent developmental phenotypes and nanotoxicity in zebrafish embryos.

Nanomaterials possess distinctive physicochemical properties and promise a wide range of applications, from advanced technology to leading-edge medicine. However, their effects on living organisms remain largely unknown. Here we report that the purified silver nanoparticles (Ag NPs) (97 ± 13 nm) incite specific developmental stage embryonic phenotypes and nanotoxicity in a dose-dependent manner, upon acute exposure of given stage embryos to the NPs (0-24 pM) for only 2 h.

Dynamic development of the protein corona on silica nanoparticles: composition and role in toxicity.

The formation and composition of the protein corona on silica (SiO2) nanoparticles (NP) with different surface chemistries was evaluated over time. Native SiO2, amine (-NH2) and carboxy (-COO(-)) modified NP were examined following incubation in mammalian growth media containing fetal bovine serum (FBS) for 1, 4, 24 and 48 hours. The protein corona transition from its early dynamic state to the later more stable corona was evaluated using mass spectrometry.

Study of charge-dependent transport and toxicity of peptide-functionalized silver nanoparticles using zebrafish embryos and single nanoparticle plasmonic spectroscopy.

Nanomaterials possess unusually high surface area-to-volume ratios and surface-determined physicochemical properties. It is essential to understand their surface-dependent toxicity in order to rationally design biocompatible nanomaterials for a wide variety of applications. In this study, we have functionalized the surfaces of silver nanoparticles (Ag NPs, 11.

Single nanoparticle spectroscopy for real-time in vivo quantitative analysis of transport and toxicity of single nanoparticles in single embryos.

Nanomaterials exhibit distinctive physicochemical properties and promise a wide range of applications from nanotechnology to nanomedicine, which raise serious concerns about their potential environmental impacts on ecosystems. Unlike any conventional chemicals, nanomaterials are highly heterogeneous, and their properties can alter over time. These unique characteristics underscore the importance of study of their properties and effects on living organisms in real time at single nanoparticle (NP) resolution.

In vivo quantitative study of sized-dependent transport and toxicity of single silver nanoparticles using zebrafish embryos.

Nanomaterials possess distinctive physicochemical properties (e.g., small sizes and high surface area-to-volume ratios) and promise a wide variety of applications, ranging from the design of high quality consumer products to effective disease diagnosis and therapy.

Design and characterization of optical nanorulers of single nanoparticles using optical microscopy and spectroscopy.

Current conventional imaging methods cannot determine sizes of single nanoparticles (NPs) in solution and living organisms at the nanometre scale, which limits the applications of NPs. In this study, we developed new imaging calibration approaches to characterize the sizes of single Ag NPs in solution at nanometre resolution by measuring their size-dependent scattering localized-surface-plasmon-resonance (LSPR) spectra and scattering intensity using dark-field optical microscopy and spectroscopy (DFOMS). We synthesized nearly spherical shape Ag NPs, ranging from 2 to 110 nm in diameter, and characterized the sizes of single NPs using high-resolution transmission electron microscopy, and the LSPR spectra and scattering intensity of single NPs using DFOMS.

Study of cytotoxic and therapeutic effects of stable and purified silver nanoparticles on tumor cells.

We have synthesized and purified silver nanoparticles (Ag NPs) (11.3+/-2.3 nm) that are stable (non-aggregated) in cell culture medium and inside single living cells.

Random walk of single gold nanoparticles in zebrafish embryos leading to stochastic toxic effects on embryonic developments.

We have synthesized and characterized stable (non-aggregating, non-photobleaching and non-blinking), nearly monodisperse and highly-pure Au nanoparticles, and used them to probe nanoparticle transport and diffusion in cleavage-stage zebrafish embryos and to study their effects on embryonic development in real-time. We found that single Au nanoparticles (11.6 +/- 0.

Probing of multidrug ABC membrane transporters of single living cells using single plasmonic nanoparticle optical probes.

Currently, molecular mechanisms of multidrug ABC (ATP-binding cassette) membrane transporters remain elusive. In this study, we synthesized and characterized purified spherically shaped silver nanoparticles (Ag NPs) (11.8 +/- 2.