Nanoparticle-aptamer conjugates for cancer cell targeting and detection

Area of Science:

• Biotechnology
• Molecular Biology
• Nanotechnology

Background:

• Aptamers are oligonucleotide sequences selected for high-affinity binding to specific targets.
• Cell-SELEX enables the selection of aptamers that recognize whole living cells.
• Existing methods for cancer cell detection require improvement in sensitivity and specificity.

Purpose of the Study:

• To generate aptamers targeting acute leukemia cells (CCRF-CEM) using cell-SELEX.
• To enhance aptamer selectivity and sensitivity through conjugation with a dual-nanoparticle system.
• To evaluate the potential of this aptamer-nanoparticle system for rapid, low-cost cancer diagnostics.

Main Methods:

• Selection of aptamers against CCRF-CEM cells via cell-SELEX.
• Conjugation of selected aptamers with magnetic nanoparticles (MNP) for cell enrichment.
• Coupling of aptamers to fluorescent silica nanoparticles (FNP) for sensitive detection.
• Validation using confocal microscopy and fluorescence microplate reader.

Main Results:

• Aptamers with nanomolar dissociation constants were generated for leukemia cells.
• The MNP-aptamer conjugate enabled selective cell collection and enrichment from complex matrices.
• The FNP-aptamer conjugate allowed highly sensitive detection of cancer cells.
• Specific cell collection and detection were confirmed at concentrations as low as 250 cells.

Conclusions:

• The developed aptamer-nanoparticle system demonstrates high affinity and specificity for cancer cells.
• This approach offers a promising rapid, low-cost method for cancer cell detection and enrichment.
• The dual-nanoparticle system enhances diagnostic capabilities for leukemia and potentially other cancers.