Chen Chia-Yu, Papadopoulos Kyriakos D
Department of Chemical & Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States.
ACS Omega. 2020 Apr 2;5(14):7738-7744. doi: 10.1021/acsomega.9b02836. eCollection 2020 Apr 14.
The dissolution rate of nicotine in aqueous solutions of sodium chloride (NaCl) was investigated at room temperature and 70 °C by quantitatively visualizing the shrinkage rate of microscopic nicotine droplets. Four different salt concentrations were used: 15 wt % (3.0 M), 20 wt % (4.3 M), 25 wt % (5.7 M), and the saturation NaCl concentration of 26 wt % (6.0 M). These results, together with the Epstein-Plesset mathematical model, provided estimates of nicotine's diffusion coefficient in the NaCl solutions. At room temperature, the dissolution rate of nicotine and diffusion coefficients decreased with increasing NaCl concentration, and below 15 wt %, the dissolution kinetics were too fast to measure accurately via optical microscopy. At the higher temperature of 70 °C, nicotine's dissolution rate showed a decrease for 15 and 20% NaCl. However, at near-saturation 25% NaCl, nicotine's dissolution rate did not exhibit significant change for the two temperatures, and for 26%, dissolution was higher at 70 °C than at room temperature.
通过定量观察微观尼古丁液滴的收缩速率，研究了室温及70℃下尼古丁在氯化钠（NaCl）水溶液中的溶解速率。使用了四种不同的盐浓度：15 wt%（3.0 M）、20 wt%（4.3 M）、25 wt%（5.7 M）以及饱和NaCl浓度26 wt%（6.0 M）。这些结果与爱泼斯坦-普列塞特数学模型一起，提供了尼古丁在NaCl溶液中扩散系数的估计值。在室温下，尼古丁的溶解速率和扩散系数随NaCl浓度的增加而降低，在15 wt%以下，溶解动力学太快，无法通过光学显微镜准确测量。在70℃的较高温度下，对于15%和20%的NaCl，尼古丁的溶解速率降低。然而，在接近饱和的25% NaCl时，尼古丁的溶解速率在两个温度下没有显著变化，对于26%，70℃时的溶解高于室温。
