pH-sensitive nanoparticles prepared from amphiphilic and biodegradable methoxy poly(ethylene glycol)-block-(polycaprolactone-graft-poly(methacrylic acid)) for oral drug delivery

2013 ◽  
Vol 4 (5) ◽  
pp. 1430-1438 ◽  
Author(s):  
Longlong Chang ◽  
Jinjian Liu ◽  
Jianhua Zhang ◽  
Liandong Deng ◽  
Anjie Dong
Keyword(s):  
Drug Delivery ◽  
Ethylene Glycol ◽  
Methacrylic Acid ◽  
Oral Drug Delivery ◽  
Ph Sensitive ◽  
Oral Drug ◽  
Poly Ethylene Glycol ◽  
Poly Ethylene

Novel pH-Sensitive Hydrogels with Peg-Tethered Chains for Oral Delivery of Calcitonin

1998 ◽  
Vol 550 ◽  
Author(s):  
M. Torres-Lugo ◽  
N.A. Peppas
Keyword(s):  
Drug Delivery ◽  
Ionic Strength ◽  
Ethylene Glycol ◽  
Methacrylic Acid ◽  
Salmon Calcitonin ◽  
Oral Delivery ◽  
Ph Sensitive ◽  
Poly Ethylene Glycol ◽  
Poly Ethylene ◽  
Tethered Chains

AbstractMajor challenges in oral delivery of peptides include the need to overcome gastric and intestinal degradation. pH -Sensitive hydrogels are suitable candidates for oral drug delivery of peptides due to their ability to respond to their environment. We have developed a new type of hydrogel composed of poly(methacrylic acid) grafted with poly(ethylene glycol) which can be used as drug delivery carriers for salmon calcitonin. These hydrogels were prepared by free radical solution polymerization and were molecularly designed to contain poly(ethylene glycol) tethered chains promoting mucosal adhesion and providing calcitonin protection, as well as methacrylic acid moieties, which act as calcium binders leading to epithelial cell junction opening. Solutions of approximately 0.1 mg/ml of salmon calcitonin were used to load the protein into the gels at pH = 7 and constant ionic strength of 0.1 M. In vitro release studies were performed at pH=7 and 37 °C, while keeping an ionic strength of 0.1 M. Calcitonin release was achieved. The release behavior was explained in terms of diffusional theories.

scholarly journals Synthesis, Characterization, and Acute Oral Toxicity Evaluation of pH-Sensitive Hydrogel Based on MPEG, Poly(ε-caprolactone), and Itaconic Acid

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Liwei Tan ◽  
Xu Xu ◽  
Jia Song ◽  
Feng Luo ◽  
Zhiyong Qian
Keyword(s):  
Ethylene Glycol ◽  
Itaconic Acid ◽  
Oral Drug Delivery ◽  
Ph Sensitive ◽  
Oral Drug ◽  
Histopathological Study ◽  
Potential Candidate ◽  
Poly Ethylene Glycol ◽  
Oral Toxicity ◽  
Poly Ethylene

A kind of chemically cross-linked pH-sensitive hydrogels based on methoxyl poly(ethylene glycol)-poly(caprolactone)-acryloyl chloride (MPEG-PCL-AC, PECA), poly(ethylene glycol) methyl ether methacrylate (MPEGMA, MEG), N,N-methylenebisacrylamide (BIS), and itaconic acid (IA) were prepared without using any organic solvent by heat-initiated free radical method. The obtained macromonomers and hydrogels were characterized by1H NMR and FT-IR, respectively. Morphology study of hydrogels was also investigated in this paper, and it showed that the hydrogels had good pH-sensitivity. The acute toxicity test and histopathological study were conducted in BALB/c mice. The results indicated that the maximum tolerance dose of the hydrogel was higher than 10000 mg/kg body weight. No morality or signs of toxicity were observed during the whole 7-day observation period. Compared to the control groups, there were no important adverse effects in the variables of hematology routine test and serum chemistry analysis both in male or female treatment group. Histopathological study also did not show any significant lesions, including heart, liver, lung, spleen, kidney, stomach, intestine, and testis. All the results demonstrated that this hydrogel was nontoxic after gavage. Thus, the hydrogel might be the biocompatible potential candidate for oral drug delivery system.

RAFT Polymerization of Dual Responsive Hyperbranched-Star Copolymers of Methacrylic Acid and Poly(Ethylene Glycol)

2017 ◽  
Vol 890 ◽  
pp. 78-81 ◽  
Author(s):  
Eduardo C. Atayde Jr. ◽  
Monica M. Berenguel ◽  
Susan D. Arco
Keyword(s):  
Drug Delivery ◽  
Ethylene Glycol ◽  
Methacrylic Acid ◽  
Morphological Changes ◽  
Spectroscopic Techniques ◽  
Block Copolymerization ◽  
Poly Ethylene Glycol ◽  
Dual Responsive ◽  
Star Copolymers ◽  
Poly Ethylene

Smart polymers are materials that respond to external stimuli via reversible morphological changes, making them potential systems for drug delivery applications. In this study, dual-responsive star copolymers with a hyperbranched core composed of ethylene glycol dimethacrylate (EGDMA) - methacrylic acid (MAA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) arms were synthesized via two-step Reversible Addition-fragmentation Chain Transfer (RAFT) block copolymerization. The synthesis involved the formation of the hyperbranched MAA core followed by arm extension with PEGMA. The formation of the hyperbranched core and subsequent copolymerization with PEGMA were verified by FT-IR and 1H-NMR spectroscopic techniques. The distinct EGDMA peak was found at 4.3 ppm while the peak attributed to PEGMA was found at around 3.5 ppm. Furthermore, the synthesized block copolymers were both temperature and pH-responsive with LCST value at 57°C and morphological transition at pH 5.6. The synthesized smart polymer was also biocompatible based on Trypan blue cytotoxicity assay. The inherent dual responsive behavior and biocompatibility of the copolymer render it a good candidate for drug delivery systems.

Sign in / Sign up

Export Citation Format

Share Document