Synthesis of polyamidoamine dendrimers having poly(ethylene glycol) grafts and their ability to encapsulate anticancer drugs.
ABSTRACT Polyamidoamine dendrimers having poly(ethylene glycol) grafts were designed as a novel drug carrier which possesses an interior for the encapsulation of drugs and a biocompatible surface. Poly(ethylene glycol) monomethyl ether with the average molecular weight of 550 or 2000 was combined to essentially every chain end of the dendrimer of the third or fourth generation via urethane bond. The poly(ethylene glycol)-attached dendrimers encapsulating anticancer drugs, adriamycin and methotrexate, were prepared by extraction with chloroform from mixtures of the poly(ethylene glycol)-attached dendrimers and varying amounts of the drugs. Their ability to encapsulate these drugs increased with increasing dendrimer generation and chain length of poly(ethylene glycol) grafts. Among the poly(ethylene glycol)-attached dendrimers prepared, the highest ability was achieved by the dendrimer of the fourth generation having the poly(ethylene glycol) grafts with the average molecular weight of 2000, which could retain 6.5 adriamycin molecules or 26 methotrexate molecules/dendrimer molecule. The methotrexate-loaded poly(ethylene glycol)-attached dendrimers released the drug slowly in an aqueous solution of low ionic strength. However, in isotonic solutions, methotrexate and adriamycin were readily released from the poly(ethylene glycol)-attached dendrimers.
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ABSTRACT: Materials offering the ability to change their characteristics in response to presented stimuli have demonstrated application in the biomedical arena, allowing control over drug delivery, protein adsorption and cell attachment to materials. Many of these smart systems are reversible, giving rise to finer control over material properties and biological interaction, useful for various therapeutic treatment strategies. Many smart materials intended for biological interaction are based around pH or thermo-responsive materials, although the use of magnetic materials, particularly in neural regeneration, has increased over the past decade. This review draws together a background of literature describing the design principles and mechanisms of smart materials. Discussion centres on recent literature regarding pH-, thermo-, magnetic and dual responsive materials, and their current applications for the treatment of neural tissue.Advanced drug delivery reviews 07/2012; · 11.96 Impact Factor
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ABSTRACT: Recent advances in drug design have led to the development of new small molecular weight chemotherapeutic agents, peptides, proteins, and nucleic acid molecules that can be used for treatment of breast cancer. However, transformation of these drug candidates into actual therapies with well-defined dosing regimens remains a significant challenge due to the limited ability to selectively deliver these drug molecules into the cytoplasm of breast cancer cells. In this article, we describe the use of liposomes, dendrimers, and polymeric micelles as carriers that can be used for delivery of anticancer drugs and their potential in breast cancer therapy. We also summarize the challenges facing the development of nucleic acid–based therapies. KeywordsBreast cancer-Chemotherapy-Nucleic acids-Liposomes-Dendrimers-MicellesCurrent Breast Cancer Reports 04/2012; 2(3):146-151.
Dataset: 7. Curr Pharm Des