Table 2.
Characteristics of spray-dried drug-free (P) and ZVD-loaded microparticles (MB1–MB2) differed in chitosan glutamate to zidovudine mass ratio.
| Formulation | Encapsulation efficiencya (%) | Moisture Content (%) | Particle size distributionb (µm) |
Viscosity (mPas at 25 °C)c | ||
|---|---|---|---|---|---|---|
| D 10 | D 50 | D 90 | ||||
| MB1 | 87.2 ± 0.8 | 5.2 ± 0.1 | 2.0 | 10.3 | 26.7 | 170 |
| MB2 | 79.0 ± 1.2 | 5.0 ± 0.2 | 2.2 | 12.2 | 28.2 | 2420 |
| P | – | 4.3 ± 0.1 | n.d. | 2850 | ||
a
Percentage of the amount of active agent encapsulated in microparticles assessed by HPLC method (Agilent Technologies 1200) vs. theoretical drug content × 100.
b
D90 value describes cumulative percentage particle undersize values for 10%, 50%, and 90% of MB by volume; assessed by Mastersizer 3000 (Malvern Instruments, Malvern, UK); n.d. – not determined.
c
Measured with a rotational viscometer Viscotester 6 Plus ThermoHaake (Thermo Scientific, Braunschweig, Germany) upon microparticles dilution in SVF (pH 4.2) in the amount corresponded to drug dose 10 mg per mL.