The particle size of PALN increased with the amount of lecithin and chitosan used in the nanoparticles. As more lecithin and chitosan were used, more drugs attracted and entrapped in the core, forming bulkier nanoparticle. The nanoparticles formed showed a size smaller than 200 nm, as a proven larger proportion of smaller nanoparticle size area in Fig. 4. To decrease the amount of chitosan injudiciously was not preferred as it might be insufficient to form a complete spherical structure with lecithin, which was bulkier with attached drug. Thus, lecithin to chitosan ratio must be adjust to ensure complete self-assembling process as it leads to rigid spherical nanoparticle occupying less space. On the other hand, increment in PEG 2000 thickens the layer on PALN, resulting in size increment (32). It is also observed that without sufficient PEG 2000, the drug residence time in systemic blood circulation might not be able to be significantly prolonged for nanoparticles.
Fig. 4 SEM image of PALN1 at a × 12,000, b× 30,000, and HRTEM image of PALNs at c× 7800