Search results for "methacrylic acid"

Chemically Fueled Volume Phase Transition of Polyacid Microgels

2021

Abstract Microgels are soft colloids that show responsive behavior and are easy to functionalize for applications. They are considered key components for future smart colloidal material systems. However, so far microgel systems have almost exclusively been studied in classical responsive switching settings using external triggers, while internally organized, autonomous control mechanisms as found in supramolecular chemistry and DNA nanotechnology relying on fuel‐driven out‐of‐equilibrium concepts have not been implemented into microgel systems. Here, we introduce chemically fueled transient volume phase transitions (VPTs) for poly(methacrylic acid) (PMAA) microgels, where the collapsed hydr…

Multicompartment Micelles with Adjustable Poly(ethylene glycol) Shell for Efficient in Vivo Photodynamic Therapy

2014

We describe the preparation of well-defined multicompartment micelles from polybutadiene-block-poly(1-methyl-2-vinyl pyridinium methyl sulfate)-block-poly(methacrylic acid) (BVqMAA) triblock terpolymers and their use as advanced drug delivery systems for photodynamic therapy (PDT). A porphyrazine derivative was incorporated into the hydrophobic core during self-assembly and served as a model drug and fluorescent probe at the same time. The initial micellar corona is formed by negatively charged PMAA and could be gradually changed to poly(ethylene glycol) (PEG) in a controlled fashion through interpolyelectrolyte complex formation of PMAA with positively charged poly(ethylene glycol)-block-p…

1991

L'etude viscosimetrique, potentiometrique et conductimetrique montre que le copolymere forme un complexe de stœchiometrie 2:1 avec le chlorure de palmityltrimethylammonium. Avec le laurylsuslfate de sodium, il y a d'abord formation d'un complexe de composition 2:1 puis par addition supplementaire du surfactant, formation d'un complexe 1:1

Development of pipette tip-based poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith for the extraction of drugs of abuse from oral flu…

2019

Abstract In this work, a monolithic polymer based on poly(methacrylic acid-co-ethylene glycol dimethacrylate) (MAA-co-EDMA) was prepared inside 200 μL pipette tips for the extraction of drug of abuse from oral fluid samples. After an appropriate surface tip modification, several polymerization mixtures with different monomer/cross-linker ratios, and percentage of porogen were studied. The most appropriate monolith to easily flow organic solvents and oral fluid samples was prepared with a MAA/EDMA ratio of 8:92 wt/wt and dodecanol containing 10 wt% toluene, as porogenic solvent. Parameters affecting the extraction procedure were evaluated and the monolith was characterized in terms of bindin…

Micelles of polyisobutylene-block-poly(methacrylic acid) diblock copolymers and their water-soluble interpolyelectrolyte complexes formed with quater…

2004

The micellization of ionic amphiphilic diblock copolymers, polyisobutylene-block-poly(methacrylic acid) (PIB-b-PMAA), with a constant degree of polymerization of the non-ionic block ðDPn ¼ 20Þ and various degrees of polymerization of the polyelectrolyte block ðDPn ¼ 100 – 425Þ was examined in aqueous media by means of fluorescence spectroscopy using pyrene as a polarity probe. The molar values of the critical micellization concentration (cmc) were found to be around 2 £ 10 26 mol/l, being nearly independent of the length of the polyelectrolyte block as well as pH (in the range 6 – 9) and ionic strength (# 0.5 M NaCl) while the specific cmc values varied from 20 to 100 mg/l. Small-angle neut…

1990

It is shown that the block-like structure of the polyampholyte poly(methacrylic acid)-block-poly(1-methyl-4-vinylpyridinium chloride) considerably influences its conformational behaviour. This specific behaviour is explained by the formation of intra-macromolecular polyelectrolyte complexes stabilized by cooperative ionic contacts between acidic and basic units near the isoelectric point (i. e. p.). The structure of the block-polyampholyte at the i. e. p. is suggested to be close to the structure of non-stoichiometric polyelectrolyte complexes. The complex formation ability of the block-polyampholyte with respect to anionic, cationic, and nonionic polymers is also studied. By means of poten…

Die vielfältigen additionsprodukte von phenylen-, naphthylen-, biphenylylen- und methylendiphenylendimethacrylaten mit radikalen aus 2,2'-azoisobutyr…

1976

Die Reaktionen von Phenylen-, Naphthylen-, Biphenylylen- und Methylendiphenylendimethacrylaten (1–4) wurden teils mit 2,2'-Azoisobutyronitril (AIBN) in Substanz oder anionisch in Losung mit Butyllithium oder Natriumdihydronaphthylid (Naphthalinnatrium), teils mit grosem Uberschus an AIBN stark verdunnt in siedendem Benzol durchgefuhrt. Neben unloslichen (vernetzten) Polymeren wurden losliche erhalten, darunter Cyclopolymere vom Typ 9, wie die Ergebnisse der Hydrolyse und anschliesende Umsetzung mit Diazomethan zu Poly(methacrylsaure-methylester)n zeigten. Die Verdunnungsreaktion ergab die Produkte 5 der unterdruckten Polymerisation, der innermolekularen Addition mit Kopf/Schwanz- und Schwan…

Partially Quarternized Amino Functional Poly(methacrylate) Terpolymers: Versatile Drug Permeability Modifiers

2011

Partially quarternized poly(methacrylate) terpolymers (Q-BBMCs) have been synthesized, based on the basic butylated methacrylate copolymer (BBMC/EUDRAGIT E), an excipient approved by the Food and Drug Administration (FDA) and to date mainly applied for tablet coatings. Via straightforward polymer modification reactions, a series of Q-BBMCs with quarternization degrees of 22%, 42%, and 65% has been prepared. Apical to basolateral transport across Caco-2 cell monolayers was investigated, employing the paracellular transported compounds trospium and mannitol. At pH 6.5 quarternization resulted in increased permeation enhancement up to 2.8-fold compared to BBMC, that is, up to 7.3-fold compared…

ABC triblock polyampholytes containing a neutral hydrophobic block, a polyacid and a polybase

1997

Well defined ABC triblock copolymers of polystyrene-block-poly(2-vinylpyridine)-block-poly(tert-butyl methacrylate) and polystyrene-block-poly(4-vinylpyridine)-block-poly(tert-butyl methacrylate) were synthesized by sequential living anionic polymerization in tetrahydrofuran. Triblock copolymers with narrow molecular weight distribution were obtained. Hydrolysis of the poly(tert-butyl methacrylate) block yields polystyrene-block-polyvinylpyridine-block-poly(methacrylic acid) which demonstrates pH-dependent solution properties. Interpolymer complexation of the polyvinylpyridine and poly(methacrylic acid) blocks in the micellar solution is studied in dependence of the pH in solution by potent…

in vitro biological evaluation of folate-functionalized block copolymer micelles for selective anti-cancer drug delivery.

2008

The main objective of this study was to evaluate the ability of folic acid-functionalized diblock copolymer micelles to improve the delivery and uptake of two poorly water-soluble anti-tumor drugs, tamoxifen and paclitaxel, to cancer cells through folate receptor targeting. The diblock copolymer used in this study comprised a hydrophilic poly[2-(methacryloyloxy)ethyl phosphorylcholine] (MPC) block, carrying at the chain end the folate targeting moiety, and a pH-sensitive hydrophobic poly[2-(diisopropylamino)ethyl methacrylate] (DPA) block (FA-MPC-DPA). The drug-loading capacities of tamoxifen- and paclitaxel-loaded micelles were determined by high performance liquid chromatography and the m…