Encapsulation of PI3K Inhibitor LY294002 within Polymer Nanoparticles Using Ion Pairing Flash Nanoprecipitation.

Flash nanoprecipitation (FNP) is a turbulent mixing process capable of reproducibly producing polymer nanoparticles loaded with active pharmaceutical ingredients (APIs). The nanoparticles produced with this method consist of a hydrophobic core surrounded by a hydrophilic corona. FNP produces nanoparticles with very high loading levels of nonionic hydrophobic APIs.

Correction to "Luteinizing Hormone Releasing Hormone-Targeted Cisplatin-Loaded Magnetite Nanoclusters for Simultaneous MR Imaging and Chemotherapy of Ovarian Cancer".

[This corrects the article PMC10317193.].

Fabrication and characterization of PLGA nanoparticles encapsulating large CRISPR-Cas9 plasmid.

Background: The clustered regularly interspaced short palindromic repeats (CRISPR) and Cas9 protein system is a revolutionary tool for gene therapy. Despite promising reports of the utility of CRISPR-Cas9 for in vivo gene editing, a principal problem in implementing this new process is delivery of high molecular weight DNA into cells.

Results: Using poly(lactic-co-glycolic acid) (PLGA), a nanoparticle carrier was designed to deliver a model CRISPR-Cas9 plasmid into primary bone marrow derived macrophages.

Design and Fabrication of Streptavidin-Functionalized, Fluorescently Labeled Polymeric Nanocarriers.

Targeted drug delivery has great potential for improving therapeutic outcomes for many diseases. Polymeric nanocarriers can improve the targeted delivery of insoluble and toxic drugs but, to achieve this, it is important to tailor the particle properties. In this study, nanoparticles comprised of poly(ethylene oxide)- b-poly(d,l-lactic acid) (PEO- b-PDLLA) were made by flash nanoprecipitation while varying the compositions of the additives poly(l-lactic acid) (PLLA), a fluorophore 6,13-bis(triisopropylsylylethynyl) (TIPS) pentacene, and poly(acrylic acid)- b-poly(d,l-lactic acid) (PAA- b-PDLLA) to characterize their effects on size, ζ potential, fluorescence, and surface functionalization.

Synthesis and Membrane Properties of Sulfonated Poly(arylene ether sulfone) Statistical Copolymers for Electrolysis of Water: Influence of Meta- and Para-Substituted Comonomers.

Two series of high molecular weight disulfonated poly(arylene ether sulfone) random copolymers were synthesized as proton exchange membranes for high-temperature water electrolyzers. These copolymers differ based on the position of the ether bonds on the aromatic rings. One series is comprised of fully para-substituted hydroquinone comonomer, and the other series incorporated 25 mol % of a meta-substituted comonomer resorcinol and 75 mol % hydroquinone.

TIPS pentacene loaded PEO-PDLLA core-shell nanoparticles have similar cellular uptake dynamics in M1 and M2 macrophages and in corresponding in vivo microenvironments.

Nanoparticle based drug delivery platforms have the potential to transform disease treatment paradigms and therapeutic strategies, especially in the context of pulmonary medicine. Once administered, nanoparticles disperse throughout the lung and many are phagocytosed by macrophages. However, there is a paucity of knowledge regarding cellular up-take dynamics of nanoparticles due largely to macrophage heterogeneity.

Remote Actuation of Magnetic Nanoparticles For Cancer Cell Selective Treatment Through Cytoskeletal Disruption.

Motion of micron and sub-micron size magnetic particles in alternating magnetic fields can activate mechanosensitive cellular functions or physically destruct cancer cells. However, such effects are usually observed with relatively large magnetic particles (>250 nm) that would be difficult if at all possible to deliver to remote sites in the body to treat disease. Here we show a completely new mechanism of selective toxicity of superparamagnetic nanoparticles (SMNP) of 7 to 8 nm in diameter to cancer cells.

Luteinizing Hormone Releasing Hormone-Targeted Cisplatin-Loaded Magnetite Nanoclusters for Simultaneous MR Imaging and Chemotherapy of Ovarian Cancer.

Given the superior soft tissue contrasts obtained by MRI and the long residence times of magnetic nanoparticles (MNPs) in soft tissues, MNP-based theranostic systems are being developed for simultaneous imaging and treatment. However, development of such theranostic nanoformulations presents significant challenges of balancing the therapeutic and diagnostic functionalities in order to achieve optimum effect from both. Here we developed a simple theranostic nanoformulation based on magnetic nanoclusters (MNCs) stabilized by a bisphosphonate-modified poly(glutamic acid)--(ethylene glycol) block copolymer and complexed with cisplatin.

Diffusion of Drug Delivery Nanoparticles into Biogels Using Time-Resolved MicroMRI.

Nanoparticle-based therapeutic agents can in some cases provide selective delivery to tumors, yet this field would greatly benefit from more detailed understanding of particle transport into and within tumor tissue. To provide fundamental information for optimizing interstitial transport of polymeric nanoparticles, we have developed a quantitative approach employing real-time analysis of nanoparticle diffusion into bulk biological hydrogels using microMRI. We use two distinct imaging approaches to probe the migration of two novel "theranostic" polymeric agents (combining drug delivery and contrast agent functions) into bulk hydrogels.

Toward design of magnetic nanoparticle clusters stabilized by biocompatible diblock copolymers for T₂-weighted MRI contrast.

We report the fabrication of magnetic particles comprised of clusters of iron oxide nanoparticles, 7.4 nm mean diameter, stabilized by a biocompatible, amphiphilic diblock copolymer, poly(ethylene oxide-b-D,L-lactide). Particles with quantitative incorporation of up to 40 wt % iron oxide and hydrodynamic sizes in the range of 80-170 nm were prepared.

Improved microchip design and application for in situ transmission electron microscopy of macromolecules.

Understanding the fundamental properties of macromolecules has enhanced the development of emerging technologies used to improve biomedical research. Currently, there is a critical need for innovative platforms that can illuminate the function of biomedical reagents in a native environment. To address this need, we have developed an in situ approach to visualize the dynamic behavior of biomedically relevant macromolecules at the nanoscale.

Changing the enzyme reaction rate in magnetic nanosuspensions by a non-heating magnetic field.

werden Enzyme, die auf magnetischen Nanopartikeln (MNPs) immobilisiert sind, beim Anlegen von magnetischen Feldern. Diese Veränderungen resultieren aus der erneuten Ausrichtung der MNPs im AC-Magnetfeld, die mit den MNP verknüpfte Polymerketten unter Belastung setzt. Für immobilisierte Enzymmoleküle auf einem MNP-Aggregat ergeben sich dadurch Deformationen und irreversible (oder lange anhaltende) Konformationsän-derungen.

Nanomedicine for intracellular therapy.

Intracellular pathogens like Salmonella evade host phagocytic killing by various mechanisms. Classical antimicrobial therapy requires multiple dosages and frequent administration of drugs for a long duration. Intracellular delivery of antimicrobials using nanoparticle may effectively devise therapies for bacterial infections.

The effect of polymer coatings on proton transverse relaxivities of aqueous suspensions of magnetic nanoparticles.

Iron oxide magnetic nanoparticles are good candidates for magnetic resonance imaging (MRI) contrast agents due to their high magnetic susceptibilities. Here we investigate 19 polyether-coated magnetite nanoparticle systems comprising three series. All systems were synthesized from the same batch of magnetite nanoparticles.

Nanostructure of PEO-polyurethane-PEO triblock copolymer micelles in water.

Novel hydrophilic triblock copolymers which form micelles in aqueous solution were studied by static and dynamic light scattering (SLS and DLS), small angle neutron scattering (SANS) and densitometry. The polymers were symmetric A-B-A block copolymers having two poly(ethylene oxide) (PEO) tail blocks and a polyurethane (PU) center segment that contained pendant carboxylic acids. The aggregation number of the micelles decreased with increasing PEO mass content.

Antibacterial efficacy of core-shell nanostructures encapsulating gentamicin against an in vivo intracellular Salmonella model.

Pluronic based core-shell nanostructures encapsulating gentamicin were designed in this study. Block copolymers of (PAA(+/-)Na-b-(PEO-b-PPO-b-PEO)-b-PAA(+/-)Na) were blended with PAA(-) Na(+) and complexed with the polycationic antibiotic gentamicin to form nanostructures. Synthesized nanostructures had a hydrodynamic diameter of 210 nm, zeta potentials of -0.

Cell uptake and in vitro toxicity of magnetic nanoparticles suitable for drug delivery.

Magnetic targeting is useful for intravascular or intracavitary drug delivery, including tumor chemotherapy or intraocular antiangiogenic therapy. For all such in vivo applications, the magnetic drug carrier must be biocompatible and nontoxic. In this work, we investigated the toxic properties of magnetic nanoparticles coated with polyethylenoxide (PEO) triblock copolymers.

Aqueous dispersions of magnetite nanoparticles complexed with copolyether dispersants: experiments and theory.

Magnetite (Fe3O4) nanoparticles have been synthesized and complexed with carboxylate-functional block copolymers, and then aqueous dispersions of the complexes were investigated as functions of their chemical and morphological structures. The block copolymer dispersants had either poly(ethylene oxide), poly(ethylene oxide-co-propylene oxide), or poly(ethylene oxide-b-propylene oxide) outer blocks, and all of them had a polyurethane center block that contained pendent carboxylate groups. The complexes were formed through interactions of the carboxylates with the surfaces of the magnetite nanoparticles.

Effect of fiber diameter on spreading, proliferation, and differentiation of osteoblastic cells on electrospun poly(lactic acid) substrates.

Electrospinning is a promising method to construct fused-fiber biomaterial scaffolds for tissue engineering applications, but the efficacy of this approach depends on how substrate topography affects cell function. Previously, it has been shown that linear, parallel raised features with length scales of 0.5-2 microm direct cell orientation through the phenomenon of contact guidance, and enhance phenotypic markers of osteoblastic differentiation.

Blends of amphiphilic trisilanolisobutyl-POSS and phosphine oxide substituted poly(dimethylsiloxane) at the air/water interface.

Mixtures of a polyhedral oligomeric silsesquioxane, trisilanolisobutyl-POSS, and a polar silicone, poly(dimethyl-co-methylvinyl-co-methyl, 2-diphenyl phosphine oxide ethyl) siloxane (PDMS-PO), spread as Langmuir monolayers at the air/water interface are used to examine the surface phase behavior and aggregation of trisilanolisobutyl-POSS as a function of silicone composition. Analyses of the surface pressure-area per monomer (Pi-A) isotherms in terms of the collapse pressures and excess Gibbs free energies of mixing indicate the monolayers form slightly negative deviation mixtures. Direct observations of surface morphology with Brewster angle microscopy in the collapsed regime reveal that the governing factor for aggregation is the collapse Pi of the component with a stronger affinity for water.