Effect of Synthesis Time on Morphology of Hollow Porous Silica Microspheres

Abstract

Hollow porous silica microspheres may be applicable as containers for the controlled release in drug delivery systems (DDS), foods, cosmetics, agrochemical, textile industry, and in other technological encapsulation use. In order to control the surface morphological properties of the silica microspheres, the effect of synthesis time on their formation was studied by a method of water-in-oil (W/O) emulsion mediated sol-gel techniques. An aqueous phase of water, ammonium hydroxide and a surfactant Tween 20 was emulsified in an oil phase of 1-octanol with a stabilizer, hydroxypropyl cellulose (HPC), and a surfactant, sorbitan monooleate (Span 80) with low hydrophile-lipophile balance (HLB) value. Tetraethyl orthosilicate (TEOS) as a silica precursor was added to the emulsion. The resulting silica particles at different synthesis time 24, 48, and 72 hours were air-dried at room temperature and calcinated at 773 K for 3 hours. The morphology of the particles was characterized by scanning electron microscopy and the particle size distribution was measured by laser diffraction. The specific surface areas were studied by 1-point BET method, and pore sizes were measured by Image Tool Software. Both dense and porous silica microspheres were observed after all three syntheses. Hollow porous silica microspheres were formed at 24 and 48 hours synthesis time. Under base catalyzed sol-gel solution, the size of silica particles was in the range of 5.4 μm to 8.2 μm, and the particles had surface area of 111 m²/g–380 m²/g. The longer synthesis time produced denser silica spheres with decreased pore sizes.<p>DOI: <a href="http://dx.doi.org/10.5755/j01.ms.18.1.1344">http://dx.doi.org/10.5755/j01.ms.18.1.1344</a></p

Facile Synthesis of Surface-Modified Hollow-Silica (SiO2) Aerogel Particles via Oil–Water–Oil Double Emulsion Method

“…Hollow silica particles can be loaded with drugs or therapeutic agents and used as carriers for targeted drug delivery. The hollow interior provides space for drug loading, while the shell can protect the drug from premature release and degradation [7]. Furthermore, Gels 2024, 10, 380 2 of 14 the controlled pore size of the silica shell also can provide a desirable release rate [8].…”

Effect of Surfactant, Solvent and Stirring Rate on the Synthesis of Silica Nanoparticles Entrapped Rifampicin

“…Other than that, most DDS are invented from silica due to the inexpensive cost and simple preparation. (Chen et al, 2012).…”

Effect of Sol-Gel Ageing Time on Three Dimensionally Ordered Macroporous Structure of 80SiO2-15CaO-5P2O5 Bioactive Glasses

“…Recently, the sol-gel method has increasingly been employed as an altemafive to the traditional high temperature techniques [2][3][4]. A variety composifions were obtained in sol-gel derived bioactive glasses [5][6][7][8][9].…”