Superparamagnetic iron oxide nanoparticles (SPIONs) have some limitations in the physiological environment, however, a modification on their surface, such as a core–shell structure with gold (SPIONs@Au), can enhance their applicability. In this study, SPIONs were synthesized by the chemical coprecipitation method, stabilized by sodium citrate, and followed by the gold-coating process. SPIONs@Au were functionalized with EGF-α-lipoic acid and chlorin e6 (Ce6)-cysteamine complexes, composing a Theranostic Nanoprobe (TP). The outcomes showed that the SPIONs@Au had changed in color to red and had an absorption band centered at 530 nm. The coating was verified in the TEM micrographs in bright and dark fields by EDS mapping, which indicated the presence of Au and Fe. The Ce6-cysteamine complex had a resonant band at 670 nm that enabled the diagnosis of biological samples using fluorescence analysis. In the measure of TNBC cell uptake, the maximum value of TP fluorescence intensity was obtained within 4 h of internalization. At 2 h, the incorporation of the TP in the cytoplasm as well as in the nuclei was observed, suggesting that it could be employed as a diagnostic marker. The PTT results showed significant percentages of apoptosis in the TNBC cell line, which confirms the efficacy of the TP.

Deforestation is a common occurrence driven by agricultural expansion, urbanization, and infrastructure development. These activities often lead to increased human interaction with ecosystems, potentially exposing individuals to Paracoccidioides spores (P. brasiliensis and P. lutzii) found in the soil, resulting in Paracoccidioidomycosis (PCM). This fungal infection is endemic to specific regions in Latin America, such as Brazil, Colombia, Venezuela, and Argentina. Diagnosis typically involves a combination of clinical assessment, imaging techniques, and laboratory examinations. P. lutzii lacks the glycoprotein Gp43, a key antigenic protein utilized in serological tests for PCM diagnosis. In this study, a colorimetric test employing gold nanoparticles (AuNPs) and label-free methodology was employed for P. lutzii detection. The effectiveness of the label-free colorimetric test was assessed using a total of 100 samples. This detection was achieved through the amplification of the gp43 gene and the use of a specific probe (5′CAGGGGTGCG3′) in conjunction with AuNPs. The receiver operating characteristic curve was employed to assess the test, revealing that the method can accurately detect P. lutzii with a sensitivity of 100% and a specificity of 100%. The findings indicate a substantial impact on remote endemic regions attributable to the implementation of cost-effective diagnostic methodologies.

Paracoccidioidomicose é uma doença que afeta principalmente os pulmões, podendo progredir por meio da disseminação para outros sistemas. A infecção é causada pelo Paracoccidioides brasiliensis, um fungo termodimórfico, que modifica sua forma de micélio para levedura a uma temperatura de 37 ºC. O objetivo deste estudo foi identificar a presença do Paracoccidioides brasiliensis por meio de nanopartículas de Ouro, combinadas com o gene gp27, usando a metodologia Label-free. Inicialmente, AuNPs foram sintetizadas com caracterização do diâmetro em 22 nm + 2 nm e uma banda de SPR centrada em 523 nm. O DNA do fungo foi amplificado usando a região do gene gp27 utilizando os oligonucleotídeos CTGTTGTTTCCGTCCTTGCGC-F e AACTCTTGGCTTTGGTTGAAG-R. Os testes colorimétricos são compostos de oligonucleotídeos específicos, AuNPs e DNA teste. Os resultados mostraram mudança de coloração da solução coloidal na presença de DNA do fungo.

Iron oxide nanoparticles (IONPs) represents a class of magnetic and biocompatible nanomaterials that have been widely used in research and medical applications, such as hyperthermia studies, as contrast agents for magnetic resonance imaging, biosensors, among others. However, their application depends on factors as surface properties, size, and morphology being appropriately balanced. IONPs can be obtained by different synthesis methods, however, chemical coprecipitation represents a simpler, easier and faster route, in which aqueous solutions of precursors containing iron (Fe³⁺) and ferrous (Fe²⁺) ions are alkalized under control of temperature and pH. This study proposes to synthesize iron oxide nanoparticles by the chemical coprecipitation method and to stabilize them with sodium citrate (IONPs-CIT) and tetramethylammonium hydroxide (IONPs-TMAOH). Furthermore, to characterize the hydrodynamic diameter and the Zeta Potential of the samples by Dynamic Light Scattering. The cytotoxicity of IONPs- CIT in the MDA-MB-468 cell line was evaluated through the analysis of mitochondrial activity.

A nanotecnologia associada a diagnóstico e tratamento de câncer está emergindo como um novo campo de pesquisa interdisciplinar, focada na concepção e aplicação de nanomateriais. O direcionamento de ativos funcionalizados a nanopartículas para a terapia fotodinâmica (TFD) vem sendo estudado por ser menos agressivo e invasivo ao organismo. Neste âmbito, este trabalho propõe o desenvolvimento de uma nanopartícula de ouro bifuncional, composta de Clorina e6 (Ce6) com o direcionamento ativo por meio do fator de crescimento epidérmico, o qual foi testado na linhagem celular MDA‑MB‑468, via TFD. Os resultados mostraram uma viabilidade celular e atividade mitocondrial dez vezes menores em comparação com Ce6 livre, considerando a mesma concentração. A espectroscopia UV-Visível e o espalhamento dinâmico de luz foram utilizada na síntese e funcionalização das nanossondas bifuncionais.