Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures
Purpose. The aim of the present work is to study the interaction of phosphate salts with trehalose and sucrose in freeze-dried matrices, particularly the effect of the salts on the glass transition temperature (T g) of the sugars. Methods. Freeze-dried trehalose and sucrose systems containing differ...
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paper:paper_07248741_v21_n9_p1615_Ohtake2023-06-08T15:43:42Z Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures Schebor, Carolina C. Freeze-drying Glass transition, sucrose Phosphate Trehalose hydroxyl group phosphate potassium dihydrogen phosphate sodium dihydrogen phosphate sucrose trehalose water acidity alkalinity analytic method article differential scanning calorimetry freeze drying glass transition temperature infrared spectroscopy molecular interaction pH priority journal temperature dependence chemistry freeze drying pH temperature thermodynamics Calorimetry, Differential Scanning Freeze Drying Hydrogen-Ion Concentration Phosphates Spectroscopy, Fourier Transform Infrared Sucrose Temperature Thermodynamics Trehalose Water Purpose. The aim of the present work is to study the interaction of phosphate salts with trehalose and sucrose in freeze-dried matrices, particularly the effect of the salts on the glass transition temperature (T g) of the sugars. Methods. Freeze-dried trehalose and sucrose systems containing different amounts of sodium or potassium phosphate were analyzed by differential scanning calorimetry to determine the Tg and by Fourier-transform infrared spectroscopy (FTIR) analysis to evaluate the strength of the interaction between sugars and phosphate ions. Results. Sucrose-phosphate mixtures show an increase in Tg up to 40°C in a broad pH range (4-9) compared to that of pure sucrose. Sucrose-phosphate mixtures exhibit a higher Tg than pure sucrose while retaining higher water contents. Trehalose-phosphate mixtures (having a Tg of 135°C at a pH of 8.8) are a better option than pure trehalose for preservation of labile materials. The -OH stretching of the sugars in the presence of phosphates decreases with increase in pH, indicating an increase in the sugar-phosphate interaction. Conclusions. Sugar-phosphate mixtures exhibit several interesting features that make them useful for lyophilization of labile molecules; Tg values much higher than those observed for the pure sugars can be obtained upon the addition of phosphate. © 2004 Springer Science+Business Media, Inc. Fil:Schebor, C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2004 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_07248741_v21_n9_p1615_Ohtake http://hdl.handle.net/20.500.12110/paper_07248741_v21_n9_p1615_Ohtake |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Freeze-drying Glass transition, sucrose Phosphate Trehalose hydroxyl group phosphate potassium dihydrogen phosphate sodium dihydrogen phosphate sucrose trehalose water acidity alkalinity analytic method article differential scanning calorimetry freeze drying glass transition temperature infrared spectroscopy molecular interaction pH priority journal temperature dependence chemistry freeze drying pH temperature thermodynamics Calorimetry, Differential Scanning Freeze Drying Hydrogen-Ion Concentration Phosphates Spectroscopy, Fourier Transform Infrared Sucrose Temperature Thermodynamics Trehalose Water |
| spellingShingle |
Freeze-drying Glass transition, sucrose Phosphate Trehalose hydroxyl group phosphate potassium dihydrogen phosphate sodium dihydrogen phosphate sucrose trehalose water acidity alkalinity analytic method article differential scanning calorimetry freeze drying glass transition temperature infrared spectroscopy molecular interaction pH priority journal temperature dependence chemistry freeze drying pH temperature thermodynamics Calorimetry, Differential Scanning Freeze Drying Hydrogen-Ion Concentration Phosphates Spectroscopy, Fourier Transform Infrared Sucrose Temperature Thermodynamics Trehalose Water Schebor, Carolina C. Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures |
| topic_facet |
Freeze-drying Glass transition, sucrose Phosphate Trehalose hydroxyl group phosphate potassium dihydrogen phosphate sodium dihydrogen phosphate sucrose trehalose water acidity alkalinity analytic method article differential scanning calorimetry freeze drying glass transition temperature infrared spectroscopy molecular interaction pH priority journal temperature dependence chemistry freeze drying pH temperature thermodynamics Calorimetry, Differential Scanning Freeze Drying Hydrogen-Ion Concentration Phosphates Spectroscopy, Fourier Transform Infrared Sucrose Temperature Thermodynamics Trehalose Water |
| description |
Purpose. The aim of the present work is to study the interaction of phosphate salts with trehalose and sucrose in freeze-dried matrices, particularly the effect of the salts on the glass transition temperature (T g) of the sugars. Methods. Freeze-dried trehalose and sucrose systems containing different amounts of sodium or potassium phosphate were analyzed by differential scanning calorimetry to determine the Tg and by Fourier-transform infrared spectroscopy (FTIR) analysis to evaluate the strength of the interaction between sugars and phosphate ions. Results. Sucrose-phosphate mixtures show an increase in Tg up to 40°C in a broad pH range (4-9) compared to that of pure sucrose. Sucrose-phosphate mixtures exhibit a higher Tg than pure sucrose while retaining higher water contents. Trehalose-phosphate mixtures (having a Tg of 135°C at a pH of 8.8) are a better option than pure trehalose for preservation of labile materials. The -OH stretching of the sugars in the presence of phosphates decreases with increase in pH, indicating an increase in the sugar-phosphate interaction. Conclusions. Sugar-phosphate mixtures exhibit several interesting features that make them useful for lyophilization of labile molecules; Tg values much higher than those observed for the pure sugars can be obtained upon the addition of phosphate. © 2004 Springer Science+Business Media, Inc. |
| author |
Schebor, Carolina C. |
| author_facet |
Schebor, Carolina C. |
| author_sort |
Schebor, Carolina C. |
| title |
Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures |
| title_short |
Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures |
| title_full |
Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures |
| title_fullStr |
Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures |
| title_full_unstemmed |
Effect of pH, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures |
| title_sort |
effect of ph, counter ion, and phosphate concentration on the glass transition temperature of freeze-dried sugar-phosphate mixtures |
| publishDate |
2004 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_07248741_v21_n9_p1615_Ohtake http://hdl.handle.net/20.500.12110/paper_07248741_v21_n9_p1615_Ohtake |
| work_keys_str_mv |
AT scheborcarolinac effectofphcounterionandphosphateconcentrationontheglasstransitiontemperatureoffreezedriedsugarphosphatemixtures |
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1768543185382932480 |