New Semi-Interpenetrating Networks Hydrogels Derived from Monosaccharide Based Oligomers, Chitosan and 2-Hydroxyethyl Methacrylate

First discovered in surfactant-water liquid crystalline systems, so-called ‘bicontinuous cubic phases’ have the property that hydropnilic and lipophilic microdomains form interpenetrating networks conforming to cubic lattices on the scale of nanometers. Later these same structures were found in star diblock copolymers, where the simultaneous continuity of elastomeric and glassy domains gives rise to unique physical properties. Today it is well-established that the symmetry and topology of such a morphology are accurately described by one of several triply-periodic minimal surfaces, and that the interface between hydrophilic and hydrophobic, or immiscible polymer, domains is described by a triply-periodic surface of constant, nonzero mean curvature. One example of such a dividing surface is shown in figure 5.The study of these structures has become of increasing importance in the past five years for two reasons:1)Bicontinuous cubic phase liquid crystals are now being polymerized to create microporous materials with monodispersed pores and readily functionalizable porewalls; figure 3 shows a TEM from a polymerized surfactant / methylmethacrylate / water cubic phase; and2)Compelling evidence has been found that these same morphologies describe biomembrane systems in a wide range of cells.

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Supramolecular Assembly of U(IV) Clusters and Superatoms

10.26434/chemrxiv.11860065 ◽

2020 ◽

Author(s):

Ian Colliard ◽

Gregory Morrosin ◽

Hans-Conrad zur Loye ◽

May Nyman

Keyword(s):

Quantum Dots ◽

Supramolecular Assembly ◽

Emergent Properties ◽

Organic Media ◽

Body Centered Cubic ◽

Cluster Anions ◽

Charge Balance ◽

Interpenetrating Networks ◽

Hierarchical Assembly ◽

Two Parameters

Superatoms are nanometer-sized molecules or particles that can form ordered lattices, mimicking their atomic counterparts. Hierarchical assembly of superatoms gives rise to emergent properties in superlattices of quantum-dots, p-block clusters, and fullerenes. Here, we introduce a family of uranium-oxysulfate cluster anions whose hierarchical assembly in water is controlled by two parameters; acidity and the countercation. In acid, larger LnIII (Ln=La-Ho) link hexamer (U6) oxoclusters into body-centered cubic frameworks, while smaller LnIII (Ln=Er-Lu &Y) promote linking of fourteen U6-clusters into hollow superclusters (U84 superatoms). U84 assembles into superlattices including cubic-closest packed, body-centered cubic, and interpenetrating networks, bridged by interstitial countercations, and U6-clusters. Divalent transition metals (TM=MnII and ZnII), with no added acid, charge-balance and promote the fusion of 10 U6 and 10 U-monomers into a wheel–shaped cluster (U70). Dissolution of U70 in organic media reveals (by small-angle Xray scattering) that differing supramolecular assemblies are accessed, controlled by TM-linking of U70-clusters.

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Substance Overview for 2-Hydroxyethyl methacrylate

The MAK-Collection for Occupational Health and Safety ◽

10.1002/3527600418.mbe86877 ◽

2014 ◽

pp. 1-1

Keyword(s):

Hydroxyethyl Methacrylate

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Development and Characterization of LBG-PVA Interpenetrating Networks Incorporating Gliclazide for Sustained Release

Current Drug Therapy ◽

10.2174/1574885515999200719143513 ◽

2020 ◽

Vol 15 ◽

Author(s):

Ashish Katoch ◽

Manju Nagpal ◽

Malkiet Kaur ◽

Manjinder Singh ◽

Geeta Aggarwal ◽

...

Keyword(s):

Solid State ◽

Sustained Release ◽

Half Life ◽

Solid State Nmr ◽

Oral Dosage ◽

Cross Linking ◽

Interpenetrating Networks ◽

Dsc Studies ◽

Biological Half Life ◽

Percentage Yield

Background: Controlled oral dosage forms have always been preferred for drugs with variable absorption, and short biological half life and frequent dosing. The prime goal with sustained release systems is to maintain uniform therapeutic blood levels for longer periods of time. Interpenetrating networks (IPNs) have been evidenced as uniform sustained release systems. In current study, polyvinyl alcohol (PVA) and locust bean gum (LBG) based IPNs were developed for the oral sustained release drug delivery of gliclazide (shows variable absorption). Method: The IPNs were synthesized by emulsion cross-linking method using glutaraldehyde (GA) as a cross linking agent. Gliclazide is a potential second generation, short-acting sulfonylurea oral hypoglycemic agent is having a short biological half-life (2-4 h), variable absorption and poor oral bioavailability. Various batches of IPNs were formulated by varying LBG: PVA ratio and evaluated for percentage yield, drug entrapment efficiency (DEE), swelling properties and in vitro drug release studies. Further characterizations were done by Fourier Transform Infrared Spectroscopy (FTIR), C13 Solid state NMR, X-Ray diffraction study (XRD), Scanning electron microscopy (SEM), and Differential scanning microscopy (DSC) studies. Results: The percentage yield, drug entrapment and equilibrium swelling was observed to be dependent on PVA-LBG ratio and GA amount. Sustained release of drug was observed in all IPN formulations (approx 59 - 86% in 8 h in various batches) with variable release kinetics. SEM studies revealed the regular structures of IPNs. FTIR, XRD, C13 Solid state NMR and DSC studies proposed that drug was successfully incorporated into the formed IPNs. Conclusion: IPNs of LBG and PVA can be used as a promising carrier with uniform sustained release characteristics.

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