Surface Coating

The surface is the interface of the nanoparticle with the environment and the ability to manipulate the surface of nanoparticles is essential for their use. Surface coating of nanoparticles refers to modification or functionalization of the surface properties of nanoparticles to enhance their imaging, drug delivery, stability, solubility, antireflection, anticorrosion, antifogging, UV resistant, prevent sulfurization, anti-microbial, self-cleaning, biological response, biocompatibility, safety, reactivity properties etc. The surface of a nanoparticle (the “core”) can be covered with a wide range of substances, which, in return, creates single- or multi-layers layer(s) (the “shell”) that can be either complete of incomplete.

Common Coating Materials

• Polymers
  • Surfactants: Compounds like cetyltrimethylammonium bromide (CTAB) or polyvinyl alcohol (PVA) can reduce surface tension and prevent aggregation.
  • Natural Polymers: Chitosan, alginate, and gelatin are biocompatible and often used in biomedical applications.
  • Synthetic Polymers: Polyethylene glycol (PEG) and polymethylmethacrylate (PMMA) can enhance stability and reduce immunogenicity.
• Silica

Silica coatings can enhance the stability and biocompatibility of metal nanoparticles. Silica is also often used to create a protective layer that can be further functionalized.

• Biomolecules

Proteins, peptides, and DNA can be used for targeted delivery and specific interaction with cells or tissues. These biomolecules can impart bioactivity to the nanoparticles.

• Inorganic Materials

Metal oxides (like titanium dioxide or iron oxide) can provide additional functionalities, such as magnetic or optical properties.

• Functionalized Ligands

Molecules that have specific affinities for targets (like antibodies or small molecules) can be used to impart functionalities to the nanoparticles, enabling targeted delivery in drug delivery systems.

• Graphene and Carbon-based Materials

Graphene oxide and carbon nanotubes can serve as coatings to enhance electrical, thermal, or mechanical properties.

• Self-assembled Monolayers

Specially designed molecules can form self-assembled monolayers on the nanoparticle surface to control properties like solubility, reactivity, and targeting characteristics.

The choice of coating materials based on the intended application, the properties of the nanoparticles, and their interaction with the environment.

STEMart employs proprietary coating technology to tailor the surface of the nanoparticles by discreetly encapsulating individual particles. This process can be used to impart a wide range of functionality to the particles which, in addition to helping to ensure success in the application, provides our customers with a great deal of flexibility in formulation with the nanoparticles. For more information about our nanoparticle surface coating service, please contact us.