Controlling the degradation of pH/temperature-sensitive injectable hydrogels based on poly(β-amino ester)

Abstract

Poly (ethylene glycol) (PEG) -poly(ε-caprolactone(CL)-co-D,L-lactide (LA)) (PCLA-PEG-PCLA) was synthesized by ring-opening polymerization to form a temperature sensitive hydrogel triblock copolymer. Poly(β-amino ester) (PAE) obtained from 1,4-butanediol diacrylate (BDA), and 4,4'-trimethylene dipiperidine (TMDP) was used as a pH sensitive moiety to conjugate to the triblock copolymer. The physicochemical properties of the temperature-sensitive triblock and pH/temperature-sensitive pentablock copolymers (PAE-PCLA-PEG-PCLA-PAE) were characterized by 1 H NMR spectroscopy and gel permeation spectroscopy. The sol-gel phase transition behavior of the PAE-PCLA-PEG-PCLA-PAE block copolymers was investigated. An aqueous solution of the copolymers (20 wt%) changed from a sol phase at pH 6.4 and 10 o C to a gel phase at pH 7.4 and 37 o C. In addition, the degradation of PAE-PCLA-PEG-PCLA-PAE was compared with that of poly(ethylene glycol) -poly(ε-caprolactone) -poly (β-amino ester) (PAE-PCL-PEG-PCL-PAE) using both in vitro and in vivo experiments. The relationship between the insulin release profile from the matrix and the degradation of these materials also investigated.

Polymeric approach to combat drug-resistant methicillin-resistant Staphylococcus aureus

“…The polymeric micelles could release HA in the presence of lipase, on irradiation of light or in appropriate wavelength range and this improved the APDT activity. These mPEG-PCL/HA micelles showed high activity against MRSA and could be used to combat MRSA infections [131][132][133][134].…”

<p>Hydrogels For Peptide Hormones Delivery: Therapeutic And Tissue Engineering Applications</p>

“…Also, super porous hydrogel (SPH) and SPH composite (SPHC) polymers enhanced the gut absorption of insulin in healthy pigs 97. Further, a pH-temperature-sensitive hydrogel composed of poly(β-amino ester)–poly(ε-caprolactone)–poly(ethylene glycol)–poly(ε-caprolactone)–poly(β-amino ester) (PAE-PCL-PEG-PCL-PAE) pentablock copolymer, as a sustained injectable system was assessed 98…”

Physicochemical properties of chitosan-poly(ethylene oxide) hydrogel modified through linoleic acid

“…Because of these beneficial properties, injectable hydrogels have been employed as scaffolds for tissue engineering of cartilages, bones and skins, as well as a carrier for either cells or/ and drugs such as mesenchymal stem cells, 3 bone morphogenic proteins, vascular endothelial growth factors and fibroblasts growth factors. [4][5][6][7][8] Injectable hydrogels have been synthesized via various methods such as Michael type addition reaction, [9][10][11][12] thermoresponsive sol-gel transitions, [13][14][15][16][17] ionic reactions, [18][19][20] hydrophobic interactions [21][22][23] and photo-polymerizations. [24][25][26] These methods demonstrated many advantages in developing a gel product.…”