The use of microemulsion in the development of nanoparticle based on acrylated palm oil product is demonstrated. Acr ylated palm oil microemulsions were prepared using ionic surfactant. Combination methods of emulsion polymerization and radiation crosslinking were applied to the microemulsion system for synthesizing nanoparticle. The ionizing radiat ion technique was introduced to generate a crosslinking reaction in the development of nanoparticle. The nanoparticle was evaluated in terms of particle diameter, surface charge, pH and conductance. Their image was captured using Tra nsmission electron microscopy (TEM). Results show that the size, charge and shape of the particles are influenced by c oncentration of surfactants, monomer concentration, radiation dose and time of storage. The study showed a promising method to produced nanoparticle. This nano-sized product has the potential to be utilized as controlled-drug-release-carrier.
UV curable coating formulation comprises urethane acrylate resin and nanosilica as filler were synthesized to develop UV curable inorganic organic hybrid composite (PUA). The surface of the nanosilica was chemically modified to improve its chemical interaction within the urethane acrylate matrix. The modification had been undertaken by applying vinyltrymetoxysilane (VTMOS) that acted as a coupling agent to produce organophilic silica shell (SIMA). The shell is linked to the silica via reaction with the surface silanol group of the silica. The disappearance of metoxy groups in VTMOS was demonstrated by FTIR spectrum. The percentage of silica particles in UV curable hybrid formulation were varied on 5%, 10%, 15%, 20% and 250% respectively. In this work, the formulation was applied on medium density fiber board (11/IDF) substrate and subsequent has been irradiated under UV light. Then, the coated MDF were characterized by several testing equipments (TGA, DSC, scratch tester, instron, SEM). From the result, we found that the addition of silica nanoparticles exhibit significant improvement in coating film properties as compared to film without silica nanoparticle includes significant improvement in its modulus and scratch resistance. This make them as promising coating candidate for MDF product. On the other hand, we also found that an increase of silica particle up to 25 wt%, the viscosity has increased rapidly indicates that it is not suitable for acrylate coating formulation due to disappearance of desired effect known as tixotrophy.
Unilamellar liposomes composed of dipalmitoylphosphatidylcholine (DPPC) were prepared by the reverse-phase
evaporation method and extrusion through a polycarbonate membrane filter. Liposomes at 0.7 mg/mL lipid concentration
in deionized water were exposed to gamma irradiation at a dose in the range 0.5 to 25 kGy. Gamma irradiation of
liposomes resulted in the degradation of DPPC lipids into free fatty acids, lysophosphatidylcholine and 1,2-palmitoylphosphatidic
acid (DPPA). The effect of gamma irradiation towards the physical stability of liposomes was investigated
by means of dynamic light scattering (DLS), transmission electron microscopy (TEM) and zeta potential analysis. From
the DLS analysis, no significant changes were observed in the hydrodynamic size of liposomes. TEM images indicate that
the liposomes surface became smoother and rounder as higher irradiation doses were applied. Zeta potential analysis
showed that gamma irradiation of DPPC liposomes at radiation doses as low as 0.5 kGy resulted in a drastic rise in the
magnitude of the zeta potential. The results also demonstrate that gamma irradiation of liposomes suspension enhanced
the overall stability of liposomes. Hence, it can be concluded that gamma irradiation on DPPC liposomes may potentially
produce liposomes with higher stability.
The fermentation of Pleurotus pulmonarius (non-irradiated) and Pleurotus pulmonarius (irradiated) were carried out in Erlenmeyer flask 500 mL (working volume 250 mL) and screened for the presence of β-glucan (1, 3:1, 6). The biomass obtained was extracted using Modified Mizuno Method to get the endopolysaccharide. The endopolysaccharides of Pleurotus pulmonarius (irradiated) contained higher content of β-glucan (1, 3:1, 6) with 16.7 g/100g crude polysaccharide compared to the non-irradiated strain. The irradiated strain was chosen for further investigation. Fractionation of endopolysaccharide Pleurotus pulmonarius (irradiated) using column chromatograph yielded 7 fractions. The first fraction (F1) contained high molecular weight fraction ~ 105 Da which potential immunomodulation characteristics. The Pleurotus pulmonarius (irradiated) was produced in a 5 L air-lift bioreactor. The highest biomass was obtained at air flowrate of 2 L/min, yielding productivity of 2.56 g/L.d.