Ultrasmall-in-Nano: Why Size Matters.

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Gold nanoparticles (AuNPs) are increasingly utilized in nanomedicine due to their tunable physicochemical properties.
• Controlling AuNP properties is crucial for optimizing their biological fate in diagnostics and therapy.
• Particle size significantly influences AuNP behavior, including optical properties and biological interactions.

Purpose of the Study:

• To review the impact of gold nanoparticle size on key properties relevant to in vivo applications.
• To explore synthesis methods for ultrasmall AuNPs and novel ultrasmall-in-nano constructs.
• To summarize the in vitro and in vivo applications and outcomes of these advanced AuNP architectures.

Main Methods:

• Literature review of synthesis techniques for ultrasmall gold nanoparticles.
• Analysis of studies investigating size-dependent optical and biological properties of AuNPs.
• Examination of research on ultrasmall-in-nano constructs and their performance.

Main Results:

• Particle size critically affects optical characteristics, opsonization, cellular uptake, renal clearance, biodistribution, and tumor accumulation.
• Ultrasmall AuNPs exhibit unique properties beneficial for specific biomedical applications.
• Ultrasmall-in-nano constructs integrate advantages from both small and larger AuNP ranges.

Conclusions:

• Tailoring gold nanoparticle size is essential for effective in vivo diagnostics and therapeutics.
• Ultrasmall AuNPs and ultrasmall-in-nano architectures represent promising advancements in nanomedicine.
• Further research into these engineered nanoparticles will enhance their clinical translation.