Search results for "PVP"

Multi-Functional Nanogels for Tumor Targeting and Redox-Sensitive Drug and siRNA Delivery

2016

(1) Background: A new family of nanosystems able to discern between normal and tumor cells and to release a therapeutic agent in controlled way were synthetized by e-beam irradiation. This technique permits to obtain biocompatible, sterile, carboxyl-functionalized polyvinylpyrrolidone (PVP-co-acrylic acid) nanogels (NGs); (2) Methods: Here, we performed a targeting strategy based on the recognition of over-expressed proteins on tumor cells, like the folate receptor. The selective targeting was demonstrated by co-culture studies and flow cytometry analysis, using folate conjugated NGs. Moreover, nanoparticles were conjugated to a chemotherapeutic drug or to a pro-apoptotic siRNA through a gl…

Solid microcrystalline dispersion films as a new strategy to improve the dissolution rate of poorly water soluble drugs: A case study using olanzapine

2016

In this study, we evaluate the dissolution rate enhancement of solid microcrystalline dispersion (SMD) films of olanzapine (OLZ) formulated with four water-soluble polymers namely poly(N-vinylpyrrolidone) (PVP), poloxamer 188 (P188), poloxamer 407 (P407) and Soluplus(®) (SLP). Prepared formulations were characterised to determine particle size, morphology, hydrogen bonding interactions, thermal characteristics as well as in vitro dissolution studies conducted under sink conditions (pH 6.8). Particle size of OLZ in all formulations ranged between 42 and 58μm. Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC) and Hot-Stage…

Large-scale manufacturing of radiation sculptured therapeutic nanogels

2013

Nanogels (NGs), or small particles formed by physically or chemically crosslinked polymer networks, represent a niche in the development of “smart” nanoparticles for drug delivery and diagnostics. Yet, they offerunique advantages over other systems, including a large and flexible surface for multivalent bio-conjugation; an internal 3D aqueous environment for incorporation and protection of (bio)molecular drugs; the possibility to entrap light-activemolecules, metal or mineral nanoparticles for imaging or phototherapeutic purposes; stimuli-responsiveness to achieve temporal and/or site control of the release function and biocompatibility. The availability of inexpensive, robust and versatile…

Sviluppo di nanocarriers per il “drug release” controllato di biomolecole nella terapia antitumorale

2014

Una nuova generazione di nanogels (NGs) in poly(N-vinyl pyrrolidone) (PVP) è stata ottenuta mediante beta–irraggiamento (e-beam) ad alta energia mediante elettroni accelerati, che permette in tempi brevi la reticolazione di polimeri in soluzione acquosa, utilizzando acceleratori di particelle lineari. Oltre al controllo dimensionale, l’aspetto innovativo di tale tecnica è la possibilità di ottenere nanogels sterili, la cui funzionalizzazione di superficie avviene in un unico step. Inizialmente, è stata provata la loro biocompatibilità e non genotossicità in sistemi biologici, caratteristiche fondamentali per la loro applicazione in campo biomedico. Inoltre, sono stati messi a punto dei prot…

Is there scientific evidence of the mouthwashes effectiveness in reducing viral load in Covid-19? A systematic review.

2020

Background The aim of this research is to verify whether there is evidence in the literature regarding the decrease in viral load present in saliva after using three types of mouthwashes. Material and methods Clinical and/or in vitro experimental studies that have used mouthwashes as a form of intervention to reduce the viral load in saliva were included. Combinations of words and appropriate truncations were adapted for each of the seven selected electronic bases including grey literature. Results The selection of articles was carried out in two phases by two independent reviewers. After removing duplicate articles, 1245 references were maintained, and 2 articles were included in the Syste…

Crosslinking of polymers activated by electrogenerated hydroxyl radicals.

2015

Nanogels (NGs) are systems created by crosslinking of polymers taking nanosized dimensions and they have been proposed for biomedical and pharmaceutical applications due to their soft consistency, biocompatibility and good chemical properties that make them excellent drug delivery agents (1). Differently from typical hydrogels, nanogels are able to dissolve in solvents and to swell releasing the drug molecules loaded in the nano-vector. Furthermore, if properly functionalized with reactive groups, these materials can represent a very interestingly vector for different pharmacological treatments (2). Several methods have been investigated to prepare polymeric nanogels starting from preformed…

Wild

2021

Graphical abstract

Polypyrrole–palladium nanoparticles composite as efficient catalyst for Suzuki–Miyaura coupling

2012

International audience; Synthesis of a new hybrid material (Pd/PPy) composed of polypyrrole globules with uniformly incorporated Pd nanoparticles via direct redox reaction between pyrrole and Pd(NH3)(4)Cl-2 in water has been recently reported (V.A. Zinovyeva, M.A.Vorotyntsev, I. Bezverkhyy, D. Chaumont, J.-C. Hierso, Adv. Funct. Mater. 21 (2011) 1064-1075). In the actual study, this procedure has been extended to synthesize a series of Pd/PPy powders with variable palladium content and morphological parameters. Depending on the monomer-to-oxidant ratio in reaction mixture, average diameters of Pd and PPy particles may change in the ranges of 1.25-1.45 and 27-62 nm, respectively, the Pd conc…

E-Beam Crosslinked Polymeric and Bio-Hybrid Nanocarriers for Drug Delivery and Bioimaging

2014

Oligonucleotide-decorated carboxyl-modified PVP nanogels: a new platform for diagnosis and gene-therapy.

2012

Nanogels, or nanoscalar chemically crosslinked polymer networks, were generated by simultaneous crosslinking of Poly(N-vinyl pyrrolidone) (PVP) and grafting of acrylic acid (AA) monomer through e-beam irradiation of their aqueous solutions. The yield of the process is very high and no separation or complex purification procedures are required since no recourse to surfactants or organic solvents is made. The administered irradiation dose (40 kGy) imparts also sterility to the obtained nanogels in the form of aqueous dispersions. Control of particle size and size-distribution can be achieved by proper selection of the irradiation conditions. In particular, we obtained nanogel variants with av…