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Chitosan nanoparticles (NPCS) have been widely used in various fields, i.e., drug delivery, antibacterial and antifungal agents. In this study, the optimum synthesis condition of NPCS by the ionic gelation method using tripolyphosphate (TPP) as counter-ions and its characterization were determined. NPCS was prepared by mixing 10 ml of chitosan (CS) solution and 3 ml of TPP solution at various ranges of pH (3 to 4.5), the mole ratio of CS/TPP (0.02:1 to 0.1:1), and speed of 400 to 900 rpm. The molecular weight (Mv) of CS was evaluated using Ostwald viscometer. The NPCS were characterized using Particle Size Analyzer (PSA), Fourier Transform Infrared (FTIR) spectroscopy, X-Ray Diffraction (XRD) analysis, and Scanning Electron Microscopy (SEM). The results exhibited that the molecular weight of CS is 33,382.34 g/mol, in the range of low molecular weight chitosan. The optimum conditions for NPCS synthesis were obtained at pH of 3.5, CS/TPP mole ratio of 0.05:1, and mixing speed of 700 rpm. The smallest average particle size was 77.71 nm, with spherical-like shape proven by the SEM images. The FTIR spectra and X-Ray diffractogram confirmed the NPCS formation that predominantly occurred via ionic interactions of CS with TPP. [ABSTRACT FROM AUTHOR]

This study has been investigated the mass ratio effect of chitosan and sodium tripolyphosphate in the ionic gelation method to produce fine chitosan suspension. In addition, the introduced of Lab-scale beads milling using 0.08 to 0.12 mm yttrium stabilized zirconia and applied the food-grade surfactant to obtain well-dispersed particles. The suspension was characterized by particle size analyzer, FT-IR spectroscopy, and SEM. The results show that the increase in mass ratio Cs/TPP could be gradually decreasing of size based on mean size distribution. After beads milling proses and addition of tween 80 as the surfactant, the morphology of Cs/TPP can breakdown of large particles into downsizing agglomerated particles with the solid surface. It was found that the beads milling process can be applied to prepare fine Cs/TPP suspension by proper adjustment of surfactant. [ABSTRACT FROM AUTHOR]

The objective of this research was to get the mechanism of nano size chitosan particle growth during storage by observing the effect of temperature and initial concentration of chitosan. The products were analyzed using PSA to have the average of particle radius. Nanochitosan solution was prepared by ionic gelation method. This method is described as an electrostatic interaction between positively charged amine with negatively charged polyanion, such as tripolyphosphate (TPP). Chitosan was dissolved in 1% acetic acid and was stirred for 30 minutes. Tween 80 was added to avoid agglomeration. TPP was prepared by dissolving 0.336 g into distilled water. The nano size chitosan was obtained by mixing TPP and chitosan solution dropwise while stirring for 30 minutes. This step was done at 15°C and ambient temperature (about 30°C) and chitosan concentration 0.2%, 0.4% and 0.6%. The results show that temperature during ionic gelation process (15°C and 30°C) does not affect the initial size of the nanoparticles produced as well as the growth of the nanoparticles during storage. On the other hand, initial chitosan concentration strongly affects initial size of the nanoparticles produced and the growth of the nanoparticles during storage. The concentration of chitosan at 0.2%, 0.4%, 0.6% gave initial size of nanoparticle chitosan of 175.3 nm, 337.9 nm, 643.3 nm respectively. On the other hand, the growth mechanism of chitosan nanoparticle depended on its radius(R). At R<500 nm, the growth rate of nanoparticles is controlled by adsorption at the surface of the particles, while at R>500 nm, it is controlled by diffusion in the liquid film around the particles. [ABSTRACT FROM AUTHOR]

The microsphere formulations of Chit/TPP/Sm/Fe3O4/Rn were prepared by an ionic gelation technique, where Chit = chitosan, TPP = tripolyphosphate, Sm = samarium and Rn = ranitidine. Optimum of microsphere formulation exhibit magnetic and fluorescent properties with adsorption efficiency of ~92% was obtained for Chit/TPP/Sm/Fe3O4/Rn with ratio 400:500:50:1:20. Fluorescence intensity of microsphere formulations increased with the cumulative amount release of ranitidine, so that the changing of fluorescence intensity at wavelength of 590 nm referring to the Sm3+ ion could be used as indicator in DDS. With the demonstration of sustained release from microsphere formulation, it allows to investigate the applications to other drugs. [ABSTRACT FROM AUTHOR]

The aim of this study is to synthesize magnetic Fe3O4-chitosan nano and microparticles (Fe3O4-CPs) by suspension cross-linking and ionic gelation methods and investigate the effect of ultrasonication on the size, morphology and magnetic properties. The synthesized particles were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS) and vibrating sample magnetometry (VSM). The results showed that the ultrasonication decreased the mean particle diameter and enhanced magnetic properties of Fe3O4-CPs due to the Fe3O4 content. [ABSTRACT FROM AUTHOR]