2007 · 63 citations · 14 references
EducationInstructionScience EducationPhysics EducationProblem-based LearningScience InstructionConcept FormationExplanationActivitiesClassroom ExplanationsExplanation By ExamplesExplanation In Science TeachingInstructional ExplanationSelf-explanation PromptsStudent ExplanationsStudent Learning Outcomes
In this study, green chemistry was used as a tool to obtain gold nanoparticles using <i>Amphipterygium adstringens</i> extracts as a synthesis medium. Green ethanolic and aqueous extracts were obtained using ultrasound and shock wave-assisted extraction. Gold nanoparticles with sizes ranging between 100 and 150 nm were obtained with ultrasound aqueous extract. Interestingly, homogeneous quasi-spherical gold nanoparticles with sizes between 50 and 100 nm were achieved with shock wave aqueous-ethanolic extracts. Furthermore, 10 nm gold nanoparticles were obtained by the traditional methanolic macerate extraction method. The physicochemical characteristics, morphology, size, stability, and Z potential of the nanoparticles were determined using microscopic and spectroscopic techniques. The viability assay in leukemia cells (Jurkat) was performed using two different sets of gold nanoparticles, with final IC<sub>50</sub> values of 87 µM and 94.7 µM, reaching a maximum cell viability decrease of 80% The results do not indicate a significant difference between the cytotoxic effects produced by the gold nanoparticles synthesized in this study and vincristine on normal lymphoblasts (CRL-1991).
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The Cambridge handbook of multimedia learning
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