Speciation of chitosan with low and high molecular weight carboxylates in aqueous solution
| العنوان: | Speciation of chitosan with low and high molecular weight carboxylates in aqueous solution |
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| المؤلفون: | Concetta De Stefano, Salvatore Cataldo, Antonio Gianguzza, Silvio Sammartano, Daniela Piazzese |
| المساهمون: | Cataldo, S, De Stefano, C, Gianguzza, A, Piazzese, D, Sammartano, S |
| المصدر: | Chemical Speciation & Bioavailability. 21:81-91 |
| بيانات النشر: | Informa UK Limited, 2009. |
| سنة النشر: | 2009 |
| مصطلحات موضوعية: | Chemical Health and Safety, Aqueous solution, polyammonium-polycarboxylate interactions, Supporting electrolyte, Ligand, Health, Toxicology and Mutagenesis, Inorganic chemistry, chitosan, Chemical speciation, sequestration, effect of ionic strength on sequestration, Toxicology, Tricarboxylate, Medicinal chemistry, chitosan, polyammonium, polycarboxylate, speciation, sequestration, ionic strenght, Chitosan, chemistry.chemical_compound, Malonate, chemistry, Ionic strength, Settore CHIM/01 - Chimica Analitica, Carboxylate |
| الوصف: | Quantitative data on the speciation of chitosan (310 kDa) with low and high molecular weight carboxylates in aqueous solution are reported. The following carboxylic ligands were considered: monocarboxylate (butyrate); dicarboxylates (malonate, succinate, azelate); tricarboxylate (1,2,3-propa- netricarboxylate); tetracarboxylate (1,2,3,4-butanetetracarboxylate); polyacrylates (2.0 and 20 kDa); polymethacrylate (5.4 kDa). The investigation was performed by potentiometry at t 1/4 25 C, at low ionic strength (without addition of supporting electrolyte) and at I 1/4 0:15 mol L 1 (NaCl). For all the systems the formation of (chitosan)LHi species was found (L 1/4 carboxylic ligand; i 1/4 1 to 4 depending on the carboxylic ligand considered). The stability of proton – chitosan – carboxylate species depends on the number of carboxylic groups involved in the complexation, and it was possible to calculate a rough free energy value per bond DGn 1/4 15 2 kJ mol 1. By using the stability data, the quantitative seques- tering capacity of chitosan towards the carboxylates here considered [expressed as the – log(total chitosan concentration) necessary to bind 50% of carboxylate, i.e., pL50] was calculated for different pH values, at low ionic strength and at I 1/4 0:15 mol L 1. The pL50 values, ranging from 3 to 7, show that chitosan is quite a strong sequestering agent towards carboxylates. Evidences were also obtained for the different behaviour between low and high molecular weight carboxylates. |
| تدمد: | 2047-6523 0954-2299 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::241ef71ca4e84c2edf5287b7fa29e41bTest https://doi.org/10.3184/095422909x449418Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....241ef71ca4e84c2edf5287b7fa29e41b |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 20476523 09542299 |
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