Nano Zinc Oxide-Loaded Calcium Alginate Films with Potential Antibacterial Properties

作者：Bajpai Sunil K^*; Chand Navin; Chaurasia Varsha

来源：Food and Bioprocess Technology, 2012, 5(5): 1871-1881.

DOI：10.1007/s11947-011-0587-6

• Alginate
• Zinc oxide nanoparticles
• Water vapor permeability
• GAB isotherm
• E. coli

In this work, zinc oxide nanoparticles-loaded calcium alginate films were investigated for their moisture uptake behavior at different temperatures. The equilibrium uptake data was interpreted quantitatively by GAB isotherm models. The monolayer moisture contents were 0.301 +/- 0.003, 0.0214 +/- 0.092, and 0.171 +/- 0.102 at 20, 30, and 37A degrees C, respectively. The water vapor transmission rate was found to be 0.816 A +/- 0.143, 1.42 A +/- 0.045, and 1.632 A +/- 0.064 g s(-1) m(-2) respectively. For the moisture content range of 0.2 to 0.6, the net a dagger H and a dagger S values were found to be 22.73 to 11.14 KJ/mol and 0.064 to 0.034 KJ/mol/K, respectively. The moisture uptake of films increased with water activity but showed negative temperature dependence. The enthalpy of sorption (a dagger H) and differential entropy (a dagger S) were determined at different moisture content values, ranging from 0.2 to 0.6 g/g db. The two parameters showed a higher degree of correlation. The equilibrium moisture content data was used to evaluate harmonic mean temperature T (hm). Finally, the biocidal action of films was tested against model bacteria Escherichia coli.

• 出版日期2012-7