Marine diatoms as optical biosensors

Area of Science:

• Biotechnology
• Materials Science
• Nanotechnology

Background:

• Marine diatoms possess intricate silica nanostructures (frustules).
• These frustules can be chemically modified for biomolecule immobilization.
• Diatom frustules offer a sustainable and cost-effective alternative to synthetic nanomaterials.

Purpose of the Study:

• To chemically modify diatom frustules for antibody binding.
• To utilize photoluminescence changes for monitoring molecular recognition events.
• To evaluate diatom frustules as a platform for biosensing applications.

Main Methods:

• Chemical modification of Coscinodiscus concinnus diatom frustules.
• Immobilization of antibodies onto the modified frustules.
• Measurement of photoluminescence emission changes upon antibody-ligand binding.
• Comparison of binding affinity with standard Biacore measurements.

Main Results:

• Successful chemical modification of frustules for antibody conjugation.
• Photoluminescence monitoring accurately reflects molecular recognition.
• Estimated dissociation constant is comparable to Biacore measurements.
• Achieved high sensitivity (1.2±0.2 nm μM⁻¹) and a low detection limit (100 nM).

Conclusions:

• Chemically modified diatom frustules are effective for biosensing.
• This approach provides a sensitive and cost-effective method for detecting molecular interactions.
• Diatom frustules are promising candidates for lab-on-particle systems.