Polymeric Iron Chelator with Enhanced Iron Affinity as a Broad-Spectrum Antifungal Agent

Developing broad-spectrum antifungal drugs represents a pressing need for reducing the global burden of fungal infections. We took advantage of the conformational stability effect to develop a high-avidity polymeric iron chelator, 2,3-dihydroxybenzoic acid-conjugated poly(L-lysine hydrochloride) (PLL-DHBA), which exhibited a stronger iron affinity than typical siderophores produced by fungi. Minimum inhibitory concentration studies against 8 types of fungi including 37 strains showed that the PLL-DHBA iron chelator exhibited a broad-spectrum antifungal effect. Moreover, PLL-DHBA was even more potent than some traditional antifungal drugs for certain drug-resistant fungi.