Dissolved organic matter (DOM) influences inland water ecosystems through its light absorbing qualities. We investigated how pH affects light absorption by DOM with pH manipulation experiments and with data from two lake surveys. We hypothesized that: (1) light absorption and photobleaching of DOM would increase with increasing pH, and (2) as a result of photobleaching, molar absorption (i.e. l...

Environmentally sensitive hydrogels have enormous potential in various applications. Some environmental variables, such as low pH and elevated temperatures, are found in the body. For this reason, either pH-sensitive and/or temperature-sensitive hydrogels can be used for site-specific controlled drug delivery. Hydrogels that are responsive to specific molecules, such as glucose or antigens, can...

Poly(d,l-lactide-co-glycolide) (PLGA) and poly(ethylenimine) (PEI) were blended and found to form a homogeneous pH sensitive matrix for drug release. Differential scanning calorimetry (DSC) studies of the PLGA/PEI blends showed a single glass transition temperature at all compositions. Fourier transform infrared spectroscopy (FTIR) demonstrated that the PLGA carbonyl peak at 1760 cm 1 shifted t...

Ionotropic gelation method was used to entrap Ketoprofen (KP) into calcium alginate beads. KP is one of the non steroidal anti-inflammatory drugs (NSAIDs); it has a short half life (1.5-2 h) and deleterious side effects on GIT such as irritation and ulceration. Beads were investigated in-vitro for possible sustained drug release and in-vivo as a gastro-protective system for KP. The curing time ...

The present paper reports the design and preparation of an amphiphilic triblock co-polymer poly(ε-caprolactone) (PCL)-poly(6,14-dimethyl-1,3,9,11-tetraoxa-6,14-diaza-cyclohexadecane-2,10-dione) (PADMC)-PCL and the use of micelles composed of them as carriers for pH-sensitive drug release. The triblock co-polymers were synthesized via two-step ring-opening polymerization with catalysis by Novozy...

Electron-conductive polymers were first reported in 1971 by Shirakawa and co-workers [1]. They synthesized conducting polyacetylene and found that it had a considerably high conductivity relative to other organic compounds, 10 S cm 1 [1–3]. Since 1971, various conducting polymers and their synthesis mechanisms have been studied actively by many researchers [4]. The conductivities of these polym...

This work reports the design and synthesis of amino acid-based hyperbranched polymers via the combination of self-condensing vinyl polymerization (SCVP) and reversible addition–fragmentation chain transfer (RAFT) polymerization from tert-butyl carbamate (Boc)-L-valine acryloyloxyethyl ester (Boc-Val-HEA) and S-(4-vinyl)benzyl S’-butyltrithiocarbonate (VBBT) with variable degrees of branching (D...

This work reports the design and synthesis of amino acid-based hyperbranched polymers via the combination of self-condensing vinyl polymerization (SCVP) and reversible addition–fragmentation chain transfer (RAFT) polymerization from tert-butyl carbamate (Boc)-L-valine acryloyloxyethyl ester (Boc-Val-HEA) and S-(4-vinyl)benzyl S’-butyltrithiocarbonate (VBBT) with variable degrees of branching (D...