Effect and safety evaluation of MIL-101 loaded with prochloraz against rice sheath blight

Rice sheath blight (ShB), a fungal disease caused by Rhizoctonia solani, seriously threatens rice yield and quality. Prochloraz (PRO), a broad-spectrum imidazole fungicide, may cause some harm to the environment and organisms when overused. To improve its efficiency and reduce environmental impact, MIL-101, a metal-organic framework, was chosen as carrier to load prochloraz to make PRO@MIL-101.

Characterizations including high-performance liquid chromatography (HPLC), thermogravimetric analysis (TGA) and X-ray diffraction (XRD) confirmed successful drug loading, with MIL-101 maintaining a regular octahedral structure and good stability. In vitro release studies showed that PRO@MIL-101 exhibited a rapid release behavior, with a faster release under acidic conditions, and fitted the Ritger-Peppas model. PRO@MIL-101 also showed better wetting properties in contact angle and adhesion function assays. Antifungal tests indicated that PRO@MIL-101 achieved strong inhibitory effects at relatively low concentrations. Safety evaluations demonstrated that MIL-101 promoted rice growth and chlorophyll synthesis at low-to-medium concentrations, which may enhance rice disease resistance by increasing antioxidant enzyme activities.

The study successfully constructs a prochloraz delivery system based on MIL-101. The system has a drug-loading rate of ≈10%, and exhibits excellent drug release performance in an acidic environment and strong adhesion to leaf surfaces. MIL-101 is safe for rice, as it can promote rice growth and enhance stress resistance. Overall, these results suggest that the drug-loading system shows an excellent control effect on ShB, providing a new idea for reducing pesticide usage while improving efficacy of its control effect. © 2026 Society of Chemical Industry.