Showing papers by "Nicholas A. Peppas published in 2013"
TL;DR: An overview of available nanoscale drug carriers is provided by exploring the wide variety of developed nanostructures and the most commonly used moieties for targeted delivery by examining tumor physiology and the specific barriers present within both the tumor microenvironment and systemic delivery.
641 citations
TL;DR: In this review, light is shed on the current state-of-the-art in drug eluting stents, problems related to them and some of the ongoing research in this area.
149 citations
TL;DR: Emphasis is given on the advances of biomaterials as drug delivery agents and on the use of design equations and mathematical modeling to achieve a wide range of successful systems.
89 citations
TL;DR: The cytocompatibility of the polymer materials were assessed using cell lines representing the GI tract and colon cancer and were noncytotoxic at varying concentrations and exposure times.
Abstract: Amphiphilic polymer carriers were formed by polymerizing a hydrophilic, pH-responsive hydrogel composed of poly(methacrylic-grafted-ethylene glycol) (P(MAA-g-EG)) in the presence of hydrophobic PMMA nanoparticles. These polymer carriers were varied in PMMA nanoparticle content to elicit a variety of physiochemical properties which would preferentially load doxorubicin, a hydrophobic chemotherapeutic, and release doxorubicin locally in the colon for the treatment of colon cancers. Loading levels ranged from 49% to 64% and increased with increasing nanoparticle content. Doxorubicin loaded polymers were released in a physiological model where low pH was used to simulate the stomach and then stepped to more neutral conditions to simulate the upper small intestine. P(MAA-g-EG) containing nanoparticles were less mucoadhesive as determined using a tensile tester, polymer samples, and fresh porcine small intestine. The cytocompatibility of the polymer materials were assessed using cell lines representing the GI tract and colon cancer and were noncytotoxic at varying concentrations and exposure times.
54 citations
TL;DR: Major concerns remain to be addressed including cytotoxicity, particularly of quantum dots; effective dosage of nanoparticles for optimal theranostic effect; development of real-time in vivo imaging; and further improvement of gene therapy efficacy.
47 citations
TL;DR: This work has shown that the architecture of these materials is also important for directing their biological performance as well as the chemistry and the physical properties.
33 citations
TL;DR: In this paper, a series of pH-responsive hydrogel nanoparticles based on crosslinked 2-(diethylaminoethyl) methacrylate and poly(ethylene glycol) methyl ether (P(DEAEMA-g-PEGMA) was presented.
33 citations
TL;DR: This work provides a systemic comparison for ARGET ATRP and UV-initiated polycationic nanoparticles for drug delivery and a guide to deciding which type of polycationing nanoparticles have the best properties for specific applications.
30 citations
TL;DR: A new conjugate composed of doxorubicin and inulin and evaluated its potential as a new therapeutic agent for cancer treatment, finding the synergistic effect of inulin conjugated toDoxorubsicin has allowed the same cytotoxic response to be maintained or improved at lower doses as compared to doxOrubic in this research.
24 citations
TL;DR: PDEAEM micro particles of 150 µm diameter showed promise as components of a system of automated, intelligent delivery method for insulin to type I diabetics.
Abstract: Novel glucose-sensitive systems for the release of insulin from poly(diethylaminoethyl methacrylate) (PDEAEM) micro-particles and nanoparticles decorated with glucose oxidase and catalase enzymes have been developed. The effect of polymer composition and loading conditions on the insulin loading efficiency and release was studied. The optimal conditions for loading insulin into PDEAEM microparticles were found to be at a loading pH of 5.6, particle to insulin mass ratio of 7:1, a concentration of 1.0 mg/mL insulin, and a collapsing pH of approximately 9.5. Microparticles exhibited a responsive (pH) or intelligent (glucose) release of insulin from a stimulus. Microparticles that had a nominal crosslinking ratio of 10% released a third of the insulin payload after a single stimulus, compared to nearly 70% for microparticles with a 3% crosslinking ratio. PDEAEM micro particles of 150 µm diameter showed promise as components of a system of automated, intelligent delivery method for insulin to type I diabetics.
20 citations
TL;DR: Biopolymers composed of a pH-responsive, hydrophilic poly(methacrylic acid-grafted-ethylene glycol) network polymerized in the presence of poly(methyl methacrylate) nanoparticles were designed for the oral delivery of chemotherapeutics for the treatment of colon cancer.
Abstract: Biopolymers composed of a pH-responsive, hydrophilic poly(methacrylic acid-grafted-ethylene glycol) network polymerized in the presence of poly(methyl methacrylate) nanoparticles were designed for the oral delivery of chemotherapeutics for the treatment of colon cancer. An inulin–doxorubicin conjugate, designed to target the colon and improve doxorubicin efficacy, was loaded into these polymer carriers at an efficiency of 54%. Release studies indicated these polymer carriers minimized conjugate release in low pH conditions and released the conjugate at neutral pH conditions using a two-step pH experiment modeling the stomach and the small intestine. At lower concentration levels, the presence of the polymer carriers did not disrupt tight junctions as determined by transepithelial electrical resistance studies using Caco-2 and HT29-MTX cell lines which are an accurate model of the GI tract epithelia. Permeability values of unmodified doxorubicin and the inulin–doxorubicin conjugate in the presence of the p...
10 Dec 2013
TL;DR: Nanotechnology in therapeutics , Nanotechnology in therapeuticutics , کتابخانه دیجیتال جندی شاپور اهواز
Abstract: Nanotechnology in therapeutics , Nanotechnology in therapeutics , کتابخانه دیجیتال جندی شاپور اهواز
TL;DR: Comparison of material properties of polycationic nanoparticles synthesized using the techniques of UV-initiated polymerization or ARGET ATRP and relates differences in material properties to differences in molecular structure indicates increased homogeneity.
01 Jan 2013
TL;DR: In this paper, the swelling behavior of novel Dome Matrix drug delivery modules was investigated using high-resolution X-ray computed tomography (CT) studies, where surface and volume evolution of the glassy core under the gel layer were precisely described.
TL;DR: New interpenetrating polymer networks composed of hydrophilic, pH-responsive poly(methacrylic-grafted-ethylene glycol), and hydrophobic poly(n-butyl acrylate) were formed for the oral delivery of chemotherapeutics to try and develop an optimized material for the loading and release of doxorubicin, aHydrophobic Chemotherapeutic.
Abstract: New interpenetrating polymer networks (IPNs) composed of hydrophilic, pH-responsive poly(methacrylic-grafted-ethylene glycol), and hydrophobic poly(n-butyl acrylate) were formed for the oral delivery of chemotherapeutics. These amphiphilic IPNs were synthesized to express variations in swelling and hydrophobic properties to try and develop an optimized material for the loading and release of doxorubicin, a hydrophobic chemotherapeutic. Release profiles modeling the gastrointestinal (GI) transit from the stomach to the small intestine were investigated. Mucoadhesion was determined using fresh porcine small intestine, polymer samples, and a tensile tester. The biocompatibility of the materials was assessed against Caco-2 and HT29-MTX cell models representing the GI tract and SW620 cells serving as a colon cancer cell model. © 2013 American Institute of Chemical Engineers AIChE J, 59: 1472–1478, 2013
Patent•
14 Oct 2013TL;DR: Nanoscale, pH-responsive polycationic networks useful for the delivery of anionic biologic therapeutics and associated methods are described in this article, where the authors present a method to construct a polycational network from polycyclic graph.
Abstract: Nanoscale, pH-responsive polycationic networks useful for the delivery of anionic biologic therapeutics and associated methods.