Amphiphilic Multi‐Arm Block Copolymer Based on Hyperbranched Polyester, Poly(L‐lactide) and Poly(ethylene glycol) as a Drug Delivery Carrier

Abstract

A novel type of biodegradable/biocompatible amphiphilic hyperbranched copolymer (H40-PLA-b-MPEG) was synthesized. Its micellar properties were studied by DLS, fluorescence spectroscopy and TEM. The drug release profile showed that the H40-PLA-b-MPEG micelles provide an initial burst release, followed by a sustained release of the entrapped hydrophobic model drug over a period of 4 to 58 h. The copolymer degraded hydrolytically within 6 weeks under physiological conditions. The MTT assay showed no obvious cytotoxicity against a human endothelial cell line at a concentration range of 0-400 microg x mL(-1). These results indicate that the H40-PLA-b-MPEG micelles have great potential as hydrophobic drug delivery carriers.

Biodegradable Core–Multishell Nanocarriers: Influence of Inner Shell Structure on the Encapsulation Behavior of Dexamethasone and Tacrolimus

“…13 8.5 g C18b-diacid (15.0 mmol) and 2.8 g mPEG750 (3.7 mmol) were added into a Schlenk flask and stirred at 60 • C for 30 min. Afterwards, the reaction mixture was heated to 180 • C and stirred under high vacuum (<0.5 × 10 −2 mbar) for 3 h. After cooling down, the mixture was purified via column chromatography using the eluents chloroform/acetic acid (80:1), chloroform/methanol 20:1, and methanol, which yielded the product as 3.8 g of a yellow oil (yield 78%).…”

“…While a unimolecular micelle consists of simple, usually hydrophilic polymeric chains anchored to a dendritic core [12], the CMS nanocarrier is a unimolecular structure that has a branched core-unit with amphiphilic polymeric chains attached to it, which at least consist of one hydrophilic and one hydrophobic block (see Figure 1). Frequently used core structures are the polyester Boltorn ® H40 [13,14], poly (ethyleneimine) (PEI) and the highly hydrophilic hyperbranched polyglycerolamine (hPG-NH2) [15,16]. Initially designed as a unimolecular liposome, the CMS nanotransporter has been reported by our group for the transport of both hydrophilic and lipophilic guest molecules [11,15].…”

Self‐Assembly of Hyperbranched Polymers and Its Biomedical Applications

“…[ 34 , 35 ] Gong and coworkers observed the micelles around 52-111 nm from the self-assembly of hyperbranched multiarm copolymer H 40 star -(PLA-b -PEO) [PLA = poly(lactic acid), PEO = poly(ethylene oxide)]. [ 36 ] Jiang et al prepared micelles more than 100 nm from the aqueous self-assembly of HPAE grafted with PLA (HPAE-star -PLA) in the presence of bovine serum albumin (BSA). [ 37 ] Besides, some small micelles below 50 nm were advantage in encapsulating small molecules or inorganic nanoparticles (NPs) as well as in directing the self-assembly of inorganic precursors through various interactions such as host-guest interaction, hydrogen bonding or electrostatic adsorption.…”

MRI‐Visual Order–Disorder Micellar Nanostructures for Smart Cancer Theranostics

“…[21] The folic acid binds to the folate receptors on the tumour cells by active targeting, which leads to receptor-mediated endocytosis and controlled release of drug delivered to the cancer cells. [22] The hydrazone linkage is sensitive to low pH and hence the attached DOx in the nanocarrier is cleaved easily by the highly acidic environment in the tumour cells resulting in controlled release. Moreover, the inner hydrophobic shell of SPION@PS-b-PAA retains DOx without leakage during transportation.…”