Posted by Modern agriculture faces increasing pressure to enhance crop productivity and resilience in the face of climate change, resource limitations, and sustainability demands. One promising strategy involves improving the efficiency of plant growth regulators like 6-benzylaminopurine (BAP), which is widely used in micropropagation but suffers from poor solubility and stability.
These drawbacks significantly restrict its application in agricultural micropropagation. To overcome this, we explored the complexation of BAP with cyclodextrins (CDs) and cyclodextrin-based nanosponges (CD-NS) to enhance its solubility, stability, and bioavailability.
Among various natural CDs, β-cyclodextrin demonstrated the highest affinity for BAP (KF = 289.5 M⁻¹). Based on this, we synthesized two β-CD-based nanosponges using eco-friendly, solvent-free methods: one with carbonyldiimidazole (βNS-CDI) and the other with citric acid (βNS-CA). Both nanosponges showed significantly improved complexation efficiency (>87%) compared to β-CD alone (67%).
The complexes provided better protection against thermal degradation and showed favorable sustained release profiles in vitro. When applied in Prunus salicina (plum) micropropagation, BAP-loaded nanosponges—particularly βNS-CA—boosted shoot proliferation and increased endogenous BAP levels compared to standard BAP application.
These findings highlight the potential of CD-based polymers as green and efficient carriers for plant hormones, laying the foundations of the future start-up DEWY of the University of Turin. Our study lays the groundwork for more sustainable and effective hormone delivery systems in plant biotechnology.