Response of platelets to silver nanoparticles designed with different surface functionalization

Area of Science:

• Nanomedicine
• Biomaterials Science
• Hematology

Background:

• Silver nanoparticles (AgNPs) are increasingly used in medicine, but their effects on hemostasis and platelet function remain poorly understood.
• Limited data exists on platelet oxidative stress response to AgNPs and how their physicochemical properties influence platelet activation.

Purpose of the Study:

• To investigate the impact of AgNP surface functionalization on platelet viability, particle uptake, oxidative stress, and activation.
• To elucidate the role of surface chemistry in AgNP-biocompatibility with platelets.

Main Methods:

• Surface functionalization of AgNPs with AOT, PVP, PLL, and BSA.
• Evaluation of platelet viability, activation, and particle uptake using flow cytometry.
• Assessment of oxidative stress markers (glutathione, radical formation, mitochondrial membrane potential) via fluorescence assays.
• Confirmation of particle internalization using transmission electron microscopy.

Main Results:

• AgNP cytotoxicity and uptake were dose-dependent and followed the order: PLL-AgNP > BSA-AgNP > AOT-AgNP > PVP-AgNP.
• AgNP treatment induced platelet oxidative stress, including superoxide radical formation and glutathione depletion.
• All tested AgNPs caused a significant increase in P-selectin expression, indicating platelet activation.
• PLL-AgNPs uniquely increased PAC-1 expression, suggesting a stronger activation pathway.

Conclusions:

• Surface functionalization significantly dictates the biological effects of AgNPs on platelets.
• AgNP interaction with platelets involves dose-dependent uptake, cytotoxicity, and induction of oxidative stress and activation.
• Tailoring AgNP surface properties is essential for developing safe and effective AgNP-based nanomedicines.