Flow cytometry is a pivotal technique in biological and clinical research, enabling the analysis of cells and particles typically larger than 1 micrometer. Recent advancements in flow cytometry have extended its capabilities to detect and analyze nanoparticles, including engineered nanoparticles, viruses, and small bacteria, down to the nanometer scale. This progression has opened new avenues for studying nanoscale entities that were previously challenging to assess.
Gold nanoparticles (AuNPs) have emerged as essential tools in this context. Their unique optical properties, particularly surface plasmon resonance (SPR), make them highly effective in enhancing fluorescence signals, thereby improving the sensitivity of flow cytometric analyses. For instance, AuNPs conjugated with specific antibodies can amplify fluorescent signals at low antibody concentrations, facilitating more precise detection of target moleculesRoyal Society of Chemistry Publications
To optimize flow cytometer settings and performance for particles ranging from 50 nm to 400 nm, specialized size reference gold nanoparticles have been developed. These standards are crucial for calibrating instruments, ensuring consistent results across experiments, and maintaining quality control over time. For example, 90 nm size reference gold nanoparticles are specifically designed for such optimization, aiding in the evaluation of particles or organisms within this size rangeCytodiagnostics
Incorporating gold nanoparticles into flow cytometry not only enhances detection capabilities but also broadens the scope of applications, including:
Cellular Uptake Studies: Evaluating how cells internalize nanoparticles, which is vital for drug delivery research.Immunophenotyping: Identifying specific cell populations by labeling surface markers with AuNP-conjugated antibodies.
Quantification of Low-Abundance Proteins: Detecting proteins present in minimal quantities by leveraging the signal amplification properties of AuNPs.
The integration of gold nanoparticles into flow cytometry represents a significant advancement in nanobiotechnology, offering enhanced sensitivity and specificity in the analysis of nanoscale particles and cellular components. This synergy facilitates a deeper understanding of complex biological systems and supports the development of innovative diagnostic and therapeutic strategies.