Table 3. Association constant (Ka) and thermodynamic parameters ΔHo and ΔSo of different vitamin-β-cyclodextrin inclusion complexes.
| Temp/Ka | Ka × 10−3/M−1b | ΔHo/kJ mol−1b | ΔSo/J mol−1K−1b | |
|---|---|---|---|---|
| Nicotinic acid | 288.15 | 1.62 | −20.59 | −9.96 |
| 293.15 | 1.39 | |||
| 298.15 | 1.25 | |||
| 303.15 | 1.07 | |||
| 308.15 | 0.92 | |||
| 313.15 | 0.82 | |||
| Ascorbic acid | 288.15 | 4.19 | −21.67 | −5.87 |
| 293.15 | 3.58 | |||
| 298.15 | 3.10 | |||
| 303.15 | 2.68 | |||
| 308.15 | 2.33 | |||
| 313.15 | 2.03 |
aStandard uncertainties in temperature u are: u(T) = ±0.01 K.
bMean errors in Ka = ±0.02 × 10−3 M−1; ΔHo = ±0.01 kJ mol−1; ΔSo = ±0.01 J mol−1K−1.