Evaluation in zebrafish model of the toxicity of rhodamine B‐conjugated crotamine, a peptide potentially useful for diagnostics and therapeutics

Crotamine is defensin‐like cationic peptide from rattlesnake venom that possesses anticancer, antimicrobial, and antifungal properties. Despite these promising biological activities, toxicity is a major concern associated with the development of venom‐derived peptides as therapeutic agents. In the present study, we used zebrafish as a system model to evaluate the toxicity of rhodamine B‐conjugated (RhoB) crotamine derivative. The lethal toxic concentration of RhoB‐crotamine was as low as 4 μM, which effectively kill zebrafish larvae in less than 10 min. With non‐lethal concentrations (