Crotalus Durissus Terrificus venom ad- sorbed onto silica nanoparticles for potential use in serotherapy

Abstract

Ophidism is a globally neglected health problem. In Argentina, Cro-talus durissus terrificus (C.d.t.) is one of the species of greater med-ical importance since its venom (V) contains mainly crotoxin (CTX),a potent toxin responsible for its high lethality. The generation of an-tivenoms (AVs) is a costly and difficult task, and the possibility of us-ing Silica nanoparticles (SiNPs) transporting snake toxins (complexcalled nanovenom-NV-) appears as a new tool to produce them. Inthis work, we study some physicochemical properties of NV complexformed by C.d.t. V and SiNPs with diameters of 150 nm and 330 nm.Proper C.d.t V adsorption to both sizes of Stber SiNPs was con-firmed by TEM micrographs. The concentration of adsorbed V wasdetermined using UV-visible spectrometry by measuring absor-bance at 280 nm. As a result, more than 50% of different concen-trations of V (0.025 – 2 mg/ml) were adsorbed to the SiNPs. Ad-sorption isotherms were analyzed using Langmuir and Freundlichmodels to explain different forms of adsorption-NPs interaction. Itwas observed that the 150 nm NVs fit both models well (R2 0.98)whether 330 nm NVs presented a lower R2 (0.88 for Freundlich and0.87 for Langmuir). These results suggest that the proteins of theV assume the formation of multiple layers due to a heterogeneous surface with regions of high and low affinity. These findings demonstrate that SiNPs can effectively adsorb C.d.t. venom and may actas promising platforms for controlled antigen delivery. This approachopens the possibility of improving antivenom production strategies.