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Complexation hydrogels for the oral delivery of growth hormone and salmon calcitonin / Daniel A. Carr in Industrial & engineering chemistry research, Vol. 49 N° 23 (Décembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp. 11991–11995 Titre : Complexation hydrogels for the oral delivery of growth hormone and salmon calcitonin Type de document : texte imprimé Auteurs : Daniel A. Carr, Auteur ; Marta Gomez-Burgaz, Auteur ; Mathilde C. Boudes, Auteur Année de publication : 2011 Article en page(s) : pp. 11991–11995 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Hydrogels Résumé : The hydrogel system of poly(methacrylic acid-co-N-vinyl pyrrolidone) P(MAA-co-NVP) was evaluated for use as an oral delivery system for growth hormone and salmon calcitonin. These proteins were selected because of their therapeutic importance and the insight provided by evaluating the delivery of a therapeutic agent with a high molecular weight (growth hormone) and a drug with a high isoelectric point (salmon calcitonin). Growth hormone loading and release studies were performed for both P(MAA-co-NVP) and P(MAA-g-poly(ethylene glycol)) (P(MAA-g-PEG)). Loading efficiencies for the respective systems were 50.9 ± 1.8% and 57.8 ± 4.1%; weight incorporation of the protein was determined to be 3.5 ± 0.1% and 4.0 ± 0.3%. At pH 7.4, growth hormone release of 90% occurred within 45 min for P(MAA-co-NVP) microparticles; 90% release was not achieved with P(MAA-g-PEG) microparticles until 180 min. At pH 1.2, no release occurred from P(MAA-co-NVP) microparticles, but 10% release occurred from P(MAA-g-PEG) microparticles. Salmon calcitonin loading and release were shown to be affected by the negative charges of deprotonated MAA; for systems with monomer molar feed ratios of 4:1, 1:1, and 1:4 MAA/NVP, loading efficiencies were determined to be 70.6 ± 3.0%, 25.3 ± 1.2%, and 1.6 ± 1.3%. Salmon calcitonin release was minimal from the copolymer with 4:1 MAA/NVP monomer feed at pH 7.4. The release improved when the pH was raised above physiological levels. These studies confirmed that P(MAA-co-NVP) was an effective oral delivery system for high molecular weight drugs, but improvements are needed before the system could be utilized for high isoelectric point therapeutic delivery. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1008025 [article] Complexation hydrogels for the oral delivery of growth hormone and salmon calcitonin [texte imprimé] / Daniel A. Carr, Auteur ; Marta Gomez-Burgaz, Auteur ; Mathilde C. Boudes, Auteur . - 2011 . - pp. 11991–11995. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 23 (Décembre 2010) . - pp. 11991–11995 Mots-clés : Hydrogels Résumé : The hydrogel system of poly(methacrylic acid-co-N-vinyl pyrrolidone) P(MAA-co-NVP) was evaluated for use as an oral delivery system for growth hormone and salmon calcitonin. These proteins were selected because of their therapeutic importance and the insight provided by evaluating the delivery of a therapeutic agent with a high molecular weight (growth hormone) and a drug with a high isoelectric point (salmon calcitonin). Growth hormone loading and release studies were performed for both P(MAA-co-NVP) and P(MAA-g-poly(ethylene glycol)) (P(MAA-g-PEG)). Loading efficiencies for the respective systems were 50.9 ± 1.8% and 57.8 ± 4.1%; weight incorporation of the protein was determined to be 3.5 ± 0.1% and 4.0 ± 0.3%. At pH 7.4, growth hormone release of 90% occurred within 45 min for P(MAA-co-NVP) microparticles; 90% release was not achieved with P(MAA-g-PEG) microparticles until 180 min. At pH 1.2, no release occurred from P(MAA-co-NVP) microparticles, but 10% release occurred from P(MAA-g-PEG) microparticles. Salmon calcitonin loading and release were shown to be affected by the negative charges of deprotonated MAA; for systems with monomer molar feed ratios of 4:1, 1:1, and 1:4 MAA/NVP, loading efficiencies were determined to be 70.6 ± 3.0%, 25.3 ± 1.2%, and 1.6 ± 1.3%. Salmon calcitonin release was minimal from the copolymer with 4:1 MAA/NVP monomer feed at pH 7.4. The release improved when the pH was raised above physiological levels. These studies confirmed that P(MAA-co-NVP) was an effective oral delivery system for high molecular weight drugs, but improvements are needed before the system could be utilized for high isoelectric point therapeutic delivery. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1008025