Preparation and Characterization of Azadirachtin Alginate-Biosorbent Based Formulations: Water Release Kinetics and Photodegradation Study.
The botanical insecticide azadirachtin was incorporated in alginate-based granules to obtain controlled release formulations (CRFs). The basic formulation [sodium alginate (1.47%) - azadirachtin (0.28%) - water] was modified by the addition of biosorbents, obtaining homogeneous hybrid hydrogels with high azadirachtin entrapment efficiency. The effect on azadirachtin release rate caused by the incorporation of biosorbents such as lignin, humic acid, and olive pomace in alginate formulation was studied by immersion of the granules in water under static conditions. The addition of the biosorbents to the basic alginate formulation reduces the rate of release because the lignin-based formulation produces a slower release. Photodegradation experiments showed the potential of the prepared formulations in protecting azadirachtin against simulated sunlight, thus improving its stability. The results showed that formulation prepared with lignin provided extended protection. Therefore, this study provides a new procedure to encapsulate the botanical insecticide azadirachtin, improving its delivery and photostability.
Department of Chemistry and Physics, Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería , Agrifood Campus of International Excellence, CeiA3, E-04120 Almería, Spain.
Francisco
F
Flores-Céspedes
Department of Chemistry and Physics, Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería , Agrifood Campus of International Excellence, CeiA3, E-04120 Almería, Spain.
Gerardo P
GP
Martínez-Domínguez
Department of Chemistry and Physics, Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería , Agrifood Campus of International Excellence, CeiA3, E-04120 Almería, Spain.
Matilde
M
Villafranca-Sánchez
Department of Chemistry and Physics, Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería , Agrifood Campus of International Excellence, CeiA3, E-04120 Almería, Spain.
Manuel
M
Fernández-Pérez
D000327:Adsorption / Q000528:radiation effects; D000464:Alginates / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D003692:Delayed-Action Preparations / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D007306:Insecticides / Q000737:chemistry*; D007700:Kinetics; D036701:Limonins / Q000737:chemistry*; D010782:Photolysis
D000464:Alginates; D003692:Delayed-Action Preparations; D006603:Hexuronic Acids; D007306:Insecticides; D036701:Limonins; D020723:Glucuronic Acid; C010329:azadirachtin
alginate hydrogels; azadirachtin; biosorbents; controlled release; photostability