Isothermal Adsorption of Aflatoxin B(1) on HSCAS Clay

Area of Science:

• * Environmental Chemistry
• * Materials Science
• * Toxicology

Background:

• * Hydrated sodium calcium aluminosilicate (HSCAS), a phyllosilicate clay, is a commercial feed additive approved as an anticaking agent.
• * HSCAS has demonstrated efficacy in binding aflatoxins and preventing aflatoxicosis in animals.
• * Aflatoxin B(1) (AfB(1)) is a potent mycotoxin commonly found in animal feed.

Purpose of the Study:

• * To investigate and characterize the isothermal adsorption process of aflatoxin B(1) onto hydrated sodium calcium aluminosilicate (HSCAS).
• * To elucidate the binding mechanisms and physical interactions between AfB(1) and HSCAS particles.
• * To evaluate HSCAS as a potential adsorbent for AfB(1) in feed applications.

Main Methods:

• * Isothermal adsorption experiments were conducted by mixing AfB(1) with HSCAS at temperatures of 15, 25, and 37°C.
• * Adsorption data were fitted to various isotherm equations, including Langmuir, Freundlich, and Toth models, to characterize the adsorption behavior.
• * Physical characteristics of AfB(1) and HSCAS were measured and modeled to understand the adsorption mechanism.

Main Results:

• * An L-type adsorption isotherm was characterized, indicating a high affinity of HSCAS for AfB(1).
• * Analysis using multiple isotherm equations provided insights into adsorption capacity, binding affinity, enthalpy, and heterogeneity.
• * The data support a chemisorption hypothesis, suggesting AfB(1) binds to diverse sites on HSCAS, including interlamellar regions, edges, and basal surfaces.

Conclusions:

• * HSCAS exhibits significant potential as an adsorbent for aflatoxin B(1) due to its chemisorption capabilities.
• * The study provides a detailed understanding of the adsorption mechanism, crucial for optimizing HSCAS application in feed safety.
• * Chemisorption onto multiple sites on HSCAS offers a robust mechanism for mitigating aflatoxin contamination in animal feed.