Gemini lipid interfaces confer enhanced pH responsiveness and hemocompatibility on surface-engineered nanocrystals

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Developing stimuli-responsive interfaces on nanocrystals is crucial for their biomedical applications.
• Existing coatings like PEGylation have limitations in dynamic response and stability.

Purpose of the Study:

• To engineer novel gemini lipid-capped CuInZnS2 (CIZS) nanocrystals with reversible pH-responsive fluorescence.
• To evaluate their performance as a biocompatible alternative to PEGylated nanocrystals for biomedical imaging.

Main Methods:

• Synthesis of gemini N-palmitoyl homocysteine (GPHC) lipid-capped CIZS nanocrystals.
• Characterization of their pH-responsive fluorescence, photostability, and hemocompatibility.
• In vitro and in vivo studies including cytocompatibility, coagulation, tumor uptake, and biodistribution.

Main Results:

• GPHC-CIZS nanocrystals demonstrated reversible pH-responsive fluorescence and enhanced photostability (>90% emission).
• They exhibited superior hemocompatibility, improved cytocompatibility, and minimal fluorescence loss in acidic conditions.
• In vivo studies showed tumor-selective uptake, prolonged intratumoral retention, and minimal systemic toxicity.

Conclusions:

• Gemini lipid interfaces offer a compact, adaptive, and biocompatible alternative to PEGylation for nanocrystals.
• These engineered nanocrystals are suitable for environmentally responsive imaging and diagnostic applications.
• The pH-dependent aggregation behavior drives tumor selectivity and retention.