Amino Compound-Synthesized Gold Nanoparticles for SARS-CoV-2 Antigen Delivery

Autor(es)

Rego, Layane Souza ; Favaro, Marianna Teixeira Pinho ; Rodrigues-Jesus, Monica Josiane ; Andreata-Santos, Robert ; Janini, Luiz Mario Ramos ; Seckler, Marcelo Martins ; Ferreira, Luis Carlos de Souza ; Azzoni, Adriano Rodrigues

• Tipo de documento: Artigo Científico
• Fonte: PHARMACEUTICS; v. 17, n. 9, p. 15-pg., 2025-09-17.

Resumo

Background: Gold nanoparticles (AuNPs) are a promising platform for vaccine antigen delivery due to their ability to stimulate both innate and adaptive immune responses. These effects depend strongly on physicochemical properties such as size, polydispersity, morphology, and surface charge, which are in turn determined by the synthesis method. While amino acids are often used as capping agents for AuNPs, their direct use as both reducing and stabilizing agents has been rarely investigated. Objectives: This study aimed to establish an ultrasound-assisted method for synthesizing AuNPs using amino compounds as both reducing and stabilizing agents, and assess their physicochemical characteristics, antigen-binding capacity, and immunogenicity. Methods: AuNPs were synthesized using L-cysteine, L-arginine, and cysteamine as dual reducing/stabilizing agents under ultrasonic conditions. The nanoparticles were combined with a recombinant receptor-binding domain (RBD) of SARS-CoV-2 and evaluated in mice for their ability to induce antibody responses. Results: The synthesized AuNPs exhibited hydrodynamic diameters ranging from 6.3 to 12.4 nm and zeta potentials from -40.5 to +36.5 mV, depending on the amino compound used. All formulations elicited robust anti-RBD IgG responses, but virus neutralization activity varied significantly. Notably, AuNP-arginine induced the strongest neutralizing response despite lower adsorption capacity and stability, suggesting that epitope preservation and antigen presentation quality were more decisive than antigen density. Conclusions: These findings underscore the importance of nanoparticle design in optimizing antigen presentation and highlight the potential of amino compound-synthesized AuNPs as effective antigen delivery vehicles for future vaccine development. (AU)

• Processo FAPESP: 23/01153-7 - Avanços em vacinologia contra a COVID-19: desenvolvimento de novos antígenos vacinais com potencial de mitigar o escape imunológico do SARS-CoV-2
• Beneficiário: Luis Carlos de Souza Ferreira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 20/05204-7 - Desenvolvimento de nanovacinas proteicas que se auto-estruturam contra SARS-CoV-2
• Beneficiário: Luis Carlos de Souza Ferreira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 21/05661-1 - Caracterização virológica de isolados brasileiros de SARS-CoV-2 e suas capacidades de neutralização por soro de indivíduos previamente infectados e/ou vacinados
• Beneficiário: Robert Andreata Santos
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 20/08943-5 - Investigação de elementos induzidos pela resposta vacinal nos indivíduos submetidos aos testes clínicos com a vacina ChAdOx1 nCOV-19
• Beneficiário: Luiz Mário Ramos Janini
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 23/16234-2 - Nanopartículas de Ouro como Veículos de Entrega de mRNA no contexto de Vacinas e Terapias Avançadas
• Beneficiário: Adriano Rodrigues Azzoni
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 20/10700-3 - Desenvolvimento de nanovacinas SAPN contra SARS-CoV-2 utilizando os antígenos estruturais S e N
• Beneficiário: Marianna Teixeira de Pinho Favaro
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado