Cancer cell targeting using multiple aptamers conjugated on nanorods

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Molecular Biology

Background:

• Effective cancer diagnosis and therapy rely on precise molecular recognition of specific cells.
• Existing molecular probes like aptamers and antibodies may exhibit weak binding affinities, leading to suboptimal signaling and cell targeting.
• Improving the binding strength and signal amplification of molecular probes is crucial for advancing cellular studies.

Purpose of the Study:

• To develop a nanoplatform for multivalent binding of aptamers to enhance cancer cell recognition.
• To increase both the signal and binding strengths of aptamer probes for improved cellular studies.
• To create advanced molecular binders with enhanced properties for cellular imaging and targeting.

Main Methods:

• Assembly of multiple fluorophore-labeled aptamers onto gold-silver nanorods (Au-Ag NRs).
• Utilizing Au-Ag NRs as a nanoplatform to achieve multivalent interactions with cancer cell membrane receptors.
• Employing flow cytometry to quantify fluorescence signal enhancement and binding affinity.

Main Results:

• Up to 80 aptamers were attached to a single Au-Ag NR, yielding significantly stronger fluorescence signals compared to individual probes.
• The multivalent assembly of aptamers on NRs increased binding affinity with cancer cells by at least 26-fold.
• Flow cytometry revealed over a 300-fold enhancement in fluorescence signal for NR-aptamer-labeled cells.

Conclusions:

• The molecular assembly of aptamers on Au-Ag NRs offers a powerful strategy to overcome limitations of weak binding probes.
• This approach significantly improves cellular imaging and targeting, particularly for cells with low-density binding sites.
• Nanomaterial-based platforms provide advanced molecular binders with greatly enhanced properties for cellular studies.