Table III.
Apparent first order rate constants (k, h-1) and half-lives (t1/2, day) of THC-HG in various surfactant solutions in IPBS at 4 °C, 25 °C and 40 °C. Results are depicted as mean ± SD (n=3).
| Formulation | Concentration (% w/v) | 4 °C | 25 °C | 40 °C | Ea (cal/mol) | |
|---|---|---|---|---|---|---|
| IPBS | - | k x 104 | 161 ± 34.5 | 1755.7 ± 84.3 | 2556.7 ± 97.4 | 13722 |
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| t1/2 | 45.5 ± 11.3 | 3.9 ± 0.2 | 2.7 ± 0.1 | |||
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| Ion Pair | k x 104 | NDD* | 21.1 ± 0.5 | 72.2 ± 0.3 | ND** | |
|
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|||||
| t1/2 | 13.7 ± 0.3 | 4.0 ± 0.02 | ||||
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| Cremophor RH 40 | 0.1 | K x 104 | 1.9 ± 0.4 | 5.3 ± 0.1 | 13.6 ± 0.4 | 9202 |
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| t1/2 | 155.3 ± 34.4 | 54.2 ± 0.5 | 21.1 ± 0.6 | |||
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| Poloxamer 407 | 0.1 | k x 104 | 4.4 ± 1.8 | 6.8 ± 0.4 | 17.5 ± 0.6 | 3887 |
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| t1/2 | 77.1 ± 30.1 | 42.2 ± 2.3 | 16.4 ± 0.6 | |||
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| Polysorbate 80 | 0.1 | k x 104 | 1.7 ± 0.2 | 4.3 ± 0.1 | 10.7 ± 0.5 | 8536 |
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| t1/2 | 167.7 ± 15.6 | 67.7 ± 2 | 27.1 ± 1.2 | |||
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| Tyloxapol | 0.1 | k x 104 | 1.8 ± 0.5 | 4.5 ± 0.1 | 13 ± 3.5 | 9295 |
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| t1/2 | 174.9 ± 52.4 | 64.7 ± 1.8 | 23.7 ± 5.4 | |||
*
NDD – No degradation detected for one month
**
ND – Not determined