Plant-Nanoparticle Interactions with g-C₃N₄: Regulator Development, Metabolic Responses, and Physiological...

Area of Science:

• Materials Science
• Environmental Science
• Agricultural Science

Background:

• Graphitic carbon nitride (g-C3N4) is gaining attention for environmental and agricultural uses.
• Understanding the structure-property relationships of different g-C3N4 forms is crucial for optimizing applications.

Purpose of the Study:

• To synthesize and compare homogeneous (H-CN) and heterogeneous (He-CN) g-C3N4.
• To evaluate their structural, photocatalytic, and biological effects.
• To establish a structure-performance-biological effect relationship for H-CN.

Main Methods:

• Synthesis of H-CN and He-CN.
• Characterization of structure and charge separation.
• Methylene blue degradation assays for photocatalysis.
• Hydroponic lettuce growth experiments.
• Photosynthetic rate, chlorophyll content, and antioxidant enzyme activity measurements.
• Metabolomics analysis.
• HepG2 cell cytotoxicity assays.

Main Results:

• H-CN exhibited an ordered lamellar structure and superior charge separation compared to He-CN.
• H-CN achieved 92% methylene blue degradation in 3 h, versus 76% for He-CN.
• H-CN significantly enhanced lettuce growth (height, stem diameter, leaf area), photosynthesis, and chlorophyll content.
• H-CN reduced nitrate levels and reactive oxygen species (ROS) while increasing antioxidant enzyme activity.
• Metabolomics indicated enhanced nitrogen assimilation and beneficial compounds in lettuce treated with H-CN.
• H-CN showed significantly lower cytotoxicity to HepG2 cells than He-CN.

Conclusions:

• H-CN possesses superior photocatalytic activity and plant growth-promoting effects compared to He-CN.
• The findings establish a clear link between H-CN structure, its performance in environmental remediation and agriculture, and its biological impact.
• H-CN shows significant promise for agricultural applications, but careful dosage control is essential for safety and efficacy.