How do you synthesize silica nanoparticles?
Bottom-up or chemical approach involves a common route used to produce silica nanoparticles from atomic or molecular scale. Some of the widely used methods to synthesize silica nanoparticles are sol-gel process, reverse microemulsion, and flame synthesis.
What is a silica sphere?
Silica spheres are manufactured using proprietary technologies which allow the essential properties of amorphous silica to be maintained while simultaneously achieving controlled spherical shape and uniform particle size. Untreated silica spheres are typically hydrophilic and negatively charged.
How do you synthesis silica?
Synthesis of the SiO2 particle can be done by several methods such as chemical vapour deposition, plasma and combustion synthesis, hydrothermal method and also sol-gel processing [3]. Silica nanoparticles obtain by proper control over their physical and chemical characteristics.
What is hollow silica nanoparticles?
Hollow nanoparticles exhibit unique functions such as thermal insulation, low dielectricity, and abnormal light scattering, especially when the inner size reaches less than twice the mean free path of air molecules (mean free path of air is 68 nm).
How do you synthesize mesoporous silica?
The synthesis process of mesoporous silica nanoparticles (MSNPs) using the sol–gel method. (A) The surfactant (CTAB) is dissolved in water. (B) Silica precursor is then added dropwise and condensed around the surfactant template. (C) The sol–gel occurs, and silica NPs are produced.
What is sol-gel method for nanoparticle synthesis?
The sol-gel process is a more chemical method (wet chemical method) for the synthesis of various nanostructures, especially metal oxide nanoparticles. In this method, the molecular precursor (usually metal alkoxide) is dissolved in water or alcohol and converted to gel by heating and stirring by hydrolysis/alcoholysis.
What is silica microspheres used for?
These particles provide higher opacity than glass microspheres and are often used as contrast particles. Aqueous suspensions of silica microspheres rarely require the use of surfactants or stabilizers. Silane coatings enable silica microspheres to be modified to generate functional groups or alter surface properties.
How are silica microspheres made?
Silica microspheres and nanospheres are composed of synthetic amorphous silica made in a laboratory batch environment. Additional advantage of silica microspheres is glass transition temperature of over 1000 degrees Celsius, which makes them suitable for high temperature applications. …
How is precipitated silica made?
Precipitated silica is produced by the controlled neutralization of dilute sodium silicate (waterglass) by either concentrated sulfuric, hydrochloric, or carbonic acids. The raw materials are those required for the silicate: sand, soda ash, caustic soda, and water.
How is colloidal silica made?
In the most general terms colloidal silica is a dispersion of amorphous silicon dioxide (silica) particles in water. These amorphous silica particles are produced by polymerizing silica nuclei from silicate solutions under alkaline conditions to form nanometer sized silica sols with high surface area.
What are mesoporous silica nanoparticles?
Mesoporous silica nanoparticles (MSNs) are one of the most well-studied inorganic nanoparticles for the delivery of drugs and contrast agents. In order to deliver nucleic acid agents, the silica surface of the MSNs is converted to carry positive charges for the binding of DNA or siRNA.
How are mesoporous silica nanoparticles made?
Mesoporous silica nanoparticles are synthesized by reacting tetraethyl orthosilicate with a template made of micellar rods. The result is a collection of nano-sized spheres or rods that are filled with a regular arrangement of pores. The template can then be removed by washing with a solvent adjusted to the proper pH.