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.

Conventional cancer treatments have limited efficacy for aggressive subtypes such as triple-negative breast cancer (TNBC), which points to the importance of new therapeutic strategies. Functionalized nanoparticles in conjunction with photodynamic therapy (PDT) represent a promising alternative. Additionally, 3D cell culture emerges as a more effective model, as it better replicates the structural and functional characteristics of the tumor microenvironment. In this study, 3D microtumors of TNBC were cultivated and treated with PDT using gold nanoparticles functionalized with Chlorin e6 (AuNPs@Ce6). Cell viability was assessed using the MTT colorimetric assay, combined with histological analysis using hematoxylin-eosin staining. The MTT assay and histological evaluation of the 3D spheroids demonstrated that PDT with AuNPs@Ce6 effectively reduced cell viability and induced necrotic morphological changes, while maintaining biocompatibility with the non-irradiated control group. These findings reinforce the potential of this approach for further investigation in TNBC models and underscore the value of 3D cultures as physiologically relevant and ethical alternatives to animal testing.

Glioblastoma multiforme is one of the most aggressive primary brain tumours and remains highly resistant to conventional therapeutic approaches. Photodynamic therapy has emerged as a promising alternative. However, the clinical application of many photosensitisers is limited by low stability, poor solubility, and non-specific distribution in biological systems. In this study, iron oxide nanoparticles (SPIONs) were synthesised by a coprecipitation method and subsequently functionalised with 3-aminopropyltriethoxysilane (APTES) to enable the conjugation of the photosensitiser Chlorin E6 (Ce6). The resulting SPIONs@APTES–Ce6 nanoprobes were characterised using dynamic light scattering, Zeta Potential analysis, UV–Vis spectroscopy, fluorescence spectroscopy, and Fourier Transform infrared spectroscopy, confirming successful surface functionalisation and preservation of the photophysical properties of Ce6. The photodynamic activity of the nanoprobes was evaluated in vitro using the M059J glioblastoma cell line. Cell viability was assessed through complementary assays, including MTT, Trypan Blue exclusion, and resazurin reduction. The nanoprobes exhibited low dark cytotoxicity under the tested conditions. Upon light activation at 660 nm, a significant reduction in cell viability was observed, demonstrating effective photodynamic activity. These findings suggest that SPIONs@APTES–Ce6 nanoprobes may represent a potential nanostructured platform for further investigation in glioblastoma photodynamic therapy.