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Synthesis of Functionalized 10-nm Polymer-coated Gold Particles for Endothelium Targeting and Drug Delivery
Published on: January 15, 2018
Binary self-assembled monolayers modified Au nanoparticles as carriers in biological applications
Hsun-Yun Chang1, Yun-Wen You2, Hua-Yang Liao2
1Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300, Taiwan and Nano Science and Technology Program, Taiwan International Graduate Program, Institute of Physics, Academia Sinica, Taipei 115, Taiwan.
Gold nanoparticles (AuNPs) modified with binary self-assembled monolayers (SAMs) show enhanced biocompatibility and gene delivery efficiency. Optimizing surface charge and isoelectric point (IEP) is key for effective nonviral gene carriers.
Area of Science:
- Biochemistry
- Nanotechnology
- Biomaterials
Background:
- Gold nanoparticles (AuNPs) are promising nonviral carriers due to facile synthesis and conjugation.
- Self-assembled monolayers (SAMs) offer tunable interfacial properties for AuNPs.
- Surface modification is crucial for optimizing nanoparticle function in biological systems.
Purpose of the Study:
- To investigate the impact of surface potential and isoelectric point (IEP) on AuNP biocompatibility and gene delivery.
- To evaluate binary-SAM modified AuNPs as carriers for plasmid DNA.
- To determine optimal surface chemistry for enhanced endosomal escape and transfection efficiency.
Main Methods:
- Synthesis of binary-SAM modified AuNPs with varying ratios of carboxylic acid (COOH) and amine (NH2) functional groups.
- Assessment of AuNP biocompatibility using the MTT assay with HEK293T cells.
- Quantification of AuNP cellular uptake via scanning transmission electron microscopy (STEM).
- Evaluation of gene delivery efficiency using plasmid DNA encoding eGFP and fluorescence imaging.
Main Results:
- Binary-SAM modified AuNPs demonstrated high biocompatibility with HEK293T cells.
- Cellular uptake of AuNPs increased with higher surface potential.
- Transfection efficiency improved with increasing surface potential.
- Optimal transfection efficiency (60% NH2, 40% COOH) was achieved when AuNP IEP was between endosomal and cytoplasmic pH, facilitating DNA protection and release.
Conclusions:
- Binary-SAM modification provides a versatile platform for tuning AuNP surface properties.
- Surface potential and IEP are critical parameters for enhancing AuNP-mediated gene delivery.
- Targeting specific IEP values can improve endosomal escape and cytoplasmic delivery of genetic material.
