Soybean cultivation is an important source of protein for humans and animals. Brazil is the second largest producer of soybeans and the largest exporter in the world.1 In 2019, the country was responsible for producing 115 million tonnes.2 Considering the importance of soybean for the world’s economy, collecting information throughout cultivation is indispensable when it comes to trade planning, as well as local and global supply.
Topical photodynamic therapy (PDT) is a minimally invasive, clinically approved treatment for non-melanoma skin cancer that relies on the conversion of photosensitizer (PS) precursors such as 5-aminolevulinic acid (ALA) into protoporphyrin IX (PpIX), followed by light activation. However, the low skin penetration of topically applied ALA cream remains a major limitation, restricting effective PpIX accumulation in deeper tumor layers. To address this challenge, we produced dissolving microneedles (DMN) as an alternative intradermal delivery platform. Two mold types were evaluated for DMN fabrication, one with a slight edge (DMNe) and another without edges (DMNf), both maintaining a conical tip geometry. DMN were prepared with a formulation containing initially 10% ALA and 20% Gantrez® AN-139 polymer in water, produced in a few steps, and characterized. In vitro insertion studies demonstrated consistent penetration depths of approximately 250μm with minimal tip deformation. DMNf showed a better penetration efficiency than the DMNe and cream groups, and mass spectrometry confirmed uniform ALA distribution. In vitro assays in darkness confirmed the formulation's biocompatibility with tumor cells. In a murine xenograft model of nodular epidermoid carcinoma, DMN-mediated ALA delivery generated up to twice the amount of PpIX in deeper tumor regions and also caused greater PDT damage compared to cream application. These findings highlight DMN as a promising approach to enhance PDT efficacy, especially for thicker or nodular skin lesions, by enabling superior and uniform intradermal drug delivery.
Photodynamic therapy is a treatment modality that can be used to treat various types of lesions. To produce cell death, reaching a certain threshold dose of reactive oxygen species (ROS) is required. The estimation of ROS production is of paramount importance to predict the depth of necrosis and to ensure that the volume to be treated receives doses higher than the threshold. In this study, we compared a theoretical model for PDT based on Monte Carlo simulations of light irradiance and rate equations with a rat liver model. At the end of the simulation, necrosis depths and volumes were estimated, as well as the photosensitizer (PS), oxygen, and ROS concentrations at each position of the treated area. From the in vivo study, we obtained the ROS concentration threshold of about 1 mM for Photogem in rat liver. This proposed method can be used for any PS or tissue, including tissues with multiple layers. The proposed method can be used to estimate parameters for any PS or tissue, including layered tissues, as long as their parameters are known. In addition, other protocols can be tested, or compared with the standard ones, providing the bases for analyzing a diverse range of photodynamic treatment scenarios.