Silica magnetic particles are a type of nanoparticle that has both silica and magnetic properties. These nanoparticles are typically composed of a magnetic core, such as magnetite or maghemite, coated with a layer of silica. Silica magnetic particles are widely used in the biomedicine field.

Biomedical Applications of Silica Magnetic Particles： 

Silica magnetic particles hold significant promise in biomedical applications such as molecular and cellular imaging, targeted drug delivery and magnetic hyperthermia.

Molecular and Cellular Imaging: Silica magnetic particles can be functionalized with specific imaging agents, such as fluorescent dyes or contrast agents, allowing for targeted and sensitive detection of specific biomolecules or cells. This approach has shown great potential for disease diagnosis and monitoring, including cancer detection.

Targeted Drug Delivery: Silica magnetic particles have also been engineered to deliver therapeutic agents directly to targeted cells. By functionalizing the surface of the particles with specific ligands or antibodies, they can be targeted to bind to specific cells and deliver therapeutic agents, such as drugs or siRNA molecules.

Magnetic Hyperthermia: By applying alternating magnetic fields to cells targeted with these particles, the magnetic nanoparticles within the cells generate heat, leading to cell death.

Fig 1 Silica Magnetic Particles

Production of Silica Magnetic Particles： 

The most common method of producing silica magnetic particles involves a dual approach of a sol-gel process combined with functionalization of the surface of the magnetic core. During the sol-gel process, a hydrolyzed silica precursor is deposited onto a magnetic core, followed by a condensation reaction that forms the silica shell. The surface of the particles can then be functionalized with specific ligands or antibodies to target specific applications.

Another method of producing silica magnetic particles is through the controlled thermal decomposition of organometallic precursors. This process involves the reduction of magnetic ions, followed by the deposition of silica around the magnetic core.

In addition, a new method for synthesizing magnetic particles of silicon dioxide has been developed: Using calcium ions as a template to induce the growth of silica shells around magnetic cores. This method produced particles of uniform size and improved magnetic properties.

Product Description： 

Silica Magnetic Particles are prepared according to the Stober process by hydrolysis of orthosilicates in the presence of magnetite and have a hydrophilic surface with terminal Si-OH-bonds. These particles can easily be separated with conventional permanent magnets. They are extremely stable in organic solvents and at high temperatures. Silica magnetic particles can be used for nucleic acid separation and purification with high efficiency and simple operation. Magnetic silica particles are used with functional protein ligands and can be used to bind histidine-labeled proteins. Alpha Lifetech Inc. offers a list of silica magnetic particles with uniform sizes and shapes.

Quality Advantage： 

1. Highly uniform in size and shape

2. Fast magnetic response

3. Flexible: manual or automated high-throughput isolation

4. Reproducible results and lot to lot consistency: CV < 5%

Applications： 

1. Magnetic hyperthermia

2. Biomolecular separation

3. Magnetic targeting drug carrier

4. Molecular and cellular imaging