Cadmium Selenide Silica Core Shell Nanoparticles (CdSe/SiO2, 99.9%, APS: 80-100nm, Metal Salt Core)

Cadmium Selenide Silica Core-Shell Nanoparticles

Introduction

Cadmium selenide (CdSe) silica core-shell nanoparticles are composite nanomaterials consisting of a CdSe (Cadmium Selenide) core, typically composed of quantum dots, encapsulated by a silica (SiO₂) shell. This combination offers enhanced optical properties, chemical stability, and biocompatibility for a wide range of applications. The CdSe core is renowned for its luminescence properties, particularly in the visible spectrum, making it a popular material for fluorescence imaging, sensing, and light-emitting devices. The silica shell, on the other hand, provides protection from environmental degradation, enhances surface functionalization, and improves biocompatibility.

Properties CdSe-Silica Core-Shell Nanoparticles

Optical Properties:

Fluorescence: CdSe quantum dots are known for their bright fluorescence in the visible range, and their emission wavelength can be tuned based on their size, from blue to red. This makes them ideal for use in imaging, sensing, and biolabeling.

Photostability: The silica shell greatly enhances the photostability of the CdSe core by protecting it from environmental factors like oxidation and aggregation, which can degrade the optical properties over time.

Size-dependent Emission: The emission wavelength of CdSe quantum dots is size-dependent, allowing for the creation of a spectrum of fluorescent colors by controlling nanoparticle size during synthesis.

Chemical Stability:

The silica shell acts as a chemical barrier, preventing the CdSe core from direct exposure to environmental agents (e.g., moisture, oxygen) that could lead to degradation, aggregation, or leaching of toxic cadmium ions.

Surface Functionalization:

The silica shell provides a surface that is easy to functionalize with various chemical groups (e.g., amines, carboxyls, thiols) for specific targeting or biological applications. The shell can also be modified to bind biomolecules, such as antibodies, aptamers, or drugs, making these nanoparticles useful for drug delivery and biomolecular sensing.

Biocompatibility:

Silica is well-known for its biocompatibility, which ensures that these core-shell nanoparticles can be used in in vivo applications (e.g., imaging, therapy) without inducing significant toxic effects. The silica shell serves as a protective layer to ensure the safe interaction of the CdSe quantum dot with biological systems.