A thiol-terminated polyethyleneglycol (PEG)-paclitaxel (PTX) conjugate was synthesized and utilized to construct a novel drug delivery system with thiol-functionalized silica nanoparticles (SLNs) to improve the overall performance of PTX in liver cancer therapy. Drug loading was performed by coating the PTX conjugate on the surface of SLNs. The PTX-PEG/SLNs showed a binary responsive drug relea...

Chemotherapy failure remains a significant medical problem in the treatment of neoplastic disease and is thought to be due to many different factors including membrane transport, p-glycoprotein in multidrug resistance, glutathione and its related enzymes, topoisomerase II and DNA repair. Glutathione is a major constituent of non-protein thiol and participates in detoxification of chemotherapy a...

H. Khalili, S. Brocchini, P. Khaw University College London Purpose We have recently shown that Fab-PEG-Fab (FpF) molecules are antibody (MAb) mimetics [1]. Site-specific conjugation of the Fab in the region where it is naturally bound to the hinge in a MAb to each terminus of a linear PEG molecule yields the FpF. Since the PEG in FpFs appears to allow good avidity of the Fabs, and better stabi...

the characteristics of the reactions differ at the two temperatures; at 22°C the reactions follow second-order kinetics for at least 85 % of the total reaction. However, at the lower temperature, the second-order kinetic plots show distinct curvature, reflecting a differential reactivity of the thiol groups on the two subunits of the enzyme. With the largest iodoacetamide derivative studied, 2-...

The crystal structure of acetylcholinesterase from Torpedo californica complexed with the uncharged inhibitor, PEG-SH-350 (containing mainly heptameric polyethylene glycol with a terminal thiol group) is determined at 2.3 A resolution. This is an untypical acetylcholinesterase inhibitor, since it lacks the cationic moiety typical of the substrate (acetylcholine). In the crystal structure, the e...

The acetylcholine receptor from denervated rat skeletal muscle was purified by affinity chromatography and, after reduction, was treated with the affinity alkylating agent 4-(N-maleimido)benzyltri[3H]methylammonium iodide. The receptor specifically incorporated approximately 1 mol of alkylating agent per mol of 125I-labeled alpha-bungarotoxin bound. Analysis of the labeled receptor by polyacryl...

Poly(ethylene glycol) (PEG) is a linear polymer with a wide range of applications in chemical manufacturing, drug development and nanotechnology. PEG derivatives are being increasingly used to covalently modify small molecule and peptide drugs, as well as bioactive nanomaterials in order to improve solubility in biological serum, reduce immunogenicity, and enhance pharmacokinetic profiles. Here...