Table 4.
Storage stability of the lyophilized selected uncoated and coated nanoparticles at refrigerator temperature (4±1°C)
| Month | Size (nm) | PDI | EE% | Drug retention (%) | ζ-potential (mV) |
|---|---|---|---|---|---|
| Uncoated nanoparticles (F5) | |||||
| 0 | 140.30±1.50 | 0.20±0.15 | 75.30±2.60 | – | −10.50±0.20 |
| 1 | 155.90±3.10** | 0.30±0.05 | 73.50±7.30 | 97.39±6.20 | −11.70±0.30 |
| 2 | 197.80±4.40*** | 0.26±0.13 | 68.00±2.80 | 95.40±2.90 | −9.70±0.49 |
| 3 | 233.20±4.50*** | 0.40±0.030 | 71.90±4.70 | 90.20±0.58 | −10.70±0.30 |
| Coated nanoparticles (F14) | |||||
| 0 | 337.60±41.00 | 0.30±0.09 | 67.40±2.90 | – | 27.40±2.90 |
| 1 | 345.40±15.90 | 0.30±0.10 | 64.60±2.10 | 95.70±1.10 | 29.40±1.70 |
| 2 | 378.50±6.60 | 0.49±0.01 | 65.30±5.10 | 96.70±3.50 | 29.40±1.00 |
| 3 | 379.60±20.90 | 0.49±0.01 | 65.20±4.70 | 96.50±3.30 | 24.60±0.80 |
Notes: Data are expressed as mean±SD (n=3). **P<0.01 and ***P<0.001 vs initially determined size at the beginning of the storage period.
Abbreviations: PDI, polydispersity index; EE%, entrapment efficiency percentage.