I am a PhD Student in Health Sciences at U.Lusófona/U.Alcalá, which researcher area is Ionic Liquids and Controlled Delivery Systems, such as Nanotechnology.
For the scientific point of view, I am interested in Chemical Synthesis, Nanotechnology, Pharmaceutical Technology and Drug Delivery Systems.
EDUCATION
Master Degree in Pharmaceutical Sciences by U.Lusófona
Upcycled Carbon Dots as Multifunctional Boosters for Broad-Spectrum Photostable Sunscreens Gustavo Teixeira Machado, Caio Rui Chiabai, Isaac dos Santos Orgino, Leticia Neves Ferraz, Flavia Dayrell França, et al. Photochem, 2025 Sustainable ultraviolet (UV) filters that couple photoprotection with antioxidant activity are needed. Carbon dots (CDots) derived from agro-industrial waste have emerged as promising candidates. CDots were prepared from Coffea canephora (coffee leaf) residues by a one-pot microwave route and characterized by UV–Vis, FTIR, and TEM. Antioxidant capacity was determined by CUPRAC and DPPH-EPR. The photoprotective efficacy was assessed in vitro by diffuse reflectance spectrophotometry before and after solar-simulator exposure. Nearly spherical CDots (3.3 ± 0.7 nm) displayed a 4.16 eV optical bandgap and broad absorption from 200 to 400 nm. At 10 μg mL−1, CDots exhibited 24.62 ± 0.19% antioxidant activity relative to Trolox by CUPRAC, while by DPPH-EPR, they showed 99.9 ± 12.5% of radical quenching at 240 µg mL−1. Addition of 4.5% w/w (dry basis) CDots to the sunscreen system increased the in vitro SPF from 26 ± 13 to 161 ± 8 (p < 0.05) while maintaining the critical wavelength at 380 ± 0.64 nm. After 30 min of irradiation, the SPF dropped only 10%, versus 44% for the CDots-free sample (control), indicating superior photostability. Coffee leaf CDots acted as an efficient broadband UV absorber and antioxidant that markedly enhanced and stabilized a conventional sunscreen formulation. The work positions waste-derived CDots as an eco-friendly, next-generation multifunctional ingredient, aligning with circular economy principles.
Roots and rhizomes of wild Asparagus: Nutritional composition, bioactivity and nanoencapsulation of the most potent extract Khaoula Adouni, Ana Júlio, Celestino Santos-Buelga, Ana M. González-Paramás, Patrícia Filipe, et al. Food Bioscience, 2022 The nutritional composition and bioactive properties of roots and rhizomes of Asparagus stipularis were evaluated. Antioxidant activity of extracts obtained by infusion was evaluated using free radicals scavenging and reducing power methods. Porcine liver primary cell was used to check the hepatotoxicity of infusions. Results revealed that Asparagus samples are likely a source of nutrients, such as dietary fibre and essential fatty acids. HPLC-DAD-ESI/MS characterization of infusions allowed the identification and quantitation of 7 phenolic compounds, all hydroxycinnamoyl derivatives, with caffeic acid as the most abundant. Roots infusion contained the highest amounts of these compounds. It also exhibited the highest antioxidant activity in all assays, with EC50 values of 0.44 ± 0.01, 0.98 ± 0.03 and 0.64 ± 0.01 mg/mL for DPPH, ABTS and FRAP assays, respectively, with no toxicity towards PLP2 primary cell cultures (GI50 > 400 μg/mL). PLGA nanoparticles loaded with root extract were prepared using solvent-evaporation double emulsion method. Nanoparticles size was about 260 nm and a polydispersity index around 0.1, with a zeta potential of about -36 mV, as well as a good encapsulation efficiency of approximately 83%. Their morphology was analysed by SEM and spherical polymeric nanoparticles with a smooth surface were observed. FTIR and DSC were also performed, which allowed corroborating the efficacy of the encapsulation and to confirm the production of a stable and robust system to load Asparagus extracts. The developed nanoparticles are expected to be used as delivery systems for bioactive compounds of A. stipularis and they could be used as an innovative dietary supplement.
Transfersomils: From ionic liquids to a new class of nanovesicular systems Ana Júlio, João Guilherme Costa, Catarina Pereira-Leite, Tânia Santos de Almeida Nanomaterials, 2022 Ionic liquids (ILs) have increasingly been studied as key materials to upgrade the performance of many pharmaceutical formulations. In controlled delivery systems, ILs have improved multiple physicochemical properties, showing the relevance of continuing to study their incorporation into these formulations. Transfersomes are biocompatible nanovesicular systems, quite useful in controlled delivery. They have promising characteristics, such as elasticity and deformability, making them suitable for cutaneous delivery. Nonetheless, their overall properties and performance may still be improved. Herein, new TransfersomILs systems to load rutin were developed and the physicochemical properties of the formulations were assessed. These systems were prepared based on an optimized formulation obtained from a Box–Behnken factorial design (BBD). The impact of imidazole-based ILs, cholinium-based ILs, and their combinations on the cell viability of HaCaT cells and on the solubility of rutin was initially assessed. The newly developed TransfersomILs containing rutin presented a smaller size and, in general, a higher association efficiency, loading capacity, and total amount of drug release compared to the formulation without IL. The ILs also promoted the colloidal stability of the vesicles, upgrading storage stability. Thus, ILs were a bridge to develop new TransfersomILs systems with an overall improved performance.
Ionic liquids as tools to improve gel formulations containing sparingly soluble phenolic acids Ana Júlio, Nádia Remtula, Marisa Nicolai, Tânia Santos de Almeida Biomedical and Biopharmaceutical Research, 2022 Hydroxycinnamic acids, namely caffeic and p-coumaric acids, have several pharmaceutical and cosmetic applications, but due to their low aqueous solubility, their applicability can be limited. Ionic liquids (ILs) have been shown to be a valuable tool to improve the solubility and assist in the incorporation of various phenolic compounds into delivery systems. Thus, this work aims to evaluate the impact of incorporating three choline-based ILs, namely (2-hydroxyethyl)-trimethylammonium-L-phenylalanine [Cho][Phe], (2-hydroxyethyl)-trimethylammonium-L-glutamate [Cho][Glu] and (2-hydroxyethyl)-trimethylammonium-glycinate [Cho][Gly], into an aqueous gel formulation containing the poorly soluble caffeic and p-coumaric acids. The results obtained confirm that the ILs not only increase the drug solubility, but also allow higher amounts of both studied drugs to be incorporated into the gels, without interfering with the stability of the aqueous gels. Moreover, the ILs altered the fluidity of the gels, both in the absence and presence of both phenolic acids, as they increase the viscosity of the formulations, contributing to higher flow resistance of the gel, which may be better accepted by the consumer. Keywords: Ionic liquids; Hydroxycinnamic acids; Poorly soluble drugs; Gels; Increased Viscosity
Biobased ionic liquids as multitalented materials in Lipidic drug implants Ana Júlio, Anaisa Sultane, Ana Silveira Viana, Joana Portugal Mota, Tânia Santos de Almeida Pharmaceutics, 2021 Lipidic implants are valuable controlled delivery systems that present good biocompatibility and are useful for long-lasting therapies. However, these promising systems can present inflexible drug release profiles that limit their performance. Thus, finding new materials to overcome this drawback is crucial. Herein, lipidic implants containing caffeine and poorly soluble salicylic acid and rutin were developed. The inclusion of Gelucire® 50/02, sucrose, and two biobased ionic liquids, [Cho][Phe] and [Cho][Glu], were evaluated as a mean to improve the performance of the systems. The formulation procedure, dye content distribution, drug content, drug release, water content, and lipidic erosion of the developed systems were assessed. AFM analysis of the implants containing ILs was also performed. The results demonstrated that neither Gelucire® 50/02 nor sucrose were suitable tools to improve the drug release profile. In contrast, the ILs proved to be promising materials for multiple reasons; not only did they facilitate the formulation and incorporation of the studied drugs into the implants, but they also allowed a more suitable release profile, with [Cho][Glu] allowing a higher drug release due to its ability to increase surface wrinkling. Hence, this study showcases ILs as multitalented materials in lipid-based drug implants.
Upgrading the topical delivery of poorly soluble drugs using ionic liquids as a versatile tool Rita Caparica, Ana Júlio, Filipe Fernandes, Maria Eduarda M. Araújo, João Guilherme Costa, et al. International Journal of Molecular Sciences, 2021 Numerous studies are continuously being carried out in pursuit of formulations with higher performance. Problems such as poor drug solubility, which hinders drug incorporation into delivery systems and bioavailability, or limitations concerning the stability and performance of the formulations may cause difficulties, since solving all these drawbacks at once is a huge challenge. Ionic liquids (ILs), due to their tunable nature, may hypothetically be synthesized for a particular application. Therefore, predicting the impact of a particular combination of ions within an IL in drug delivery could be a useful strategy. Eight ILs, two choline amino acid ILs, two imidazole halogenated ILs, and four imidazole amino acid ILs, were prepared. Their applicability at non-toxic concentrations, for improving solubility and the incorporation of the poorly soluble, ferulic, caffeic, and p-coumaric acids, as well as rutin, into topical emulsions, was assessed. Next, the impact of the ILs on the performance of the formulations was investigated. Our study showed that choosing the appropriate IL leads to a clear upgrade of a topical emulsion, by optimizing multiple features of its performance, such as improving the delivery of poorly soluble drugs, altering the viscosity, which may lead to better sensorial features, and increasing the stability over time.
Development of ionic liquid-polymer nanoparticle hybrid systems for delivery of poorly soluble drugs Ana Júlio, Sofia A. Costa Lima, Salette Reis, Tânia Santos de Almeida, Pedro Fonte Journal of Drug Delivery Science and Technology, 2020 The low solubility and permeability of drugs are two major challenges in the development of delivery systems, thus the aim of this work was to develop ionic liquid-nanocarrier hybrid systems for delivery of poorly soluble drugs. The ionic liquid-nanocarrier hybrid system loading a poorly soluble drug model, rutin, was obtained by a modified double-emulsion technique. The ionic liquids, (2-hydroxyethyl)-trimethylammonium- l -phenylalaninate [Cho][Phe] or (2-hydroxyethyl)-trimethylammonium- l -glutaminate [Cho][Glu] were used, to obtain the systems, at concentrations where cell viability is maintained. The formulation was optimized to obtain carriers with optimal physicochemical features. The hybrid nanosystems had a diameter less than 500 nm, with good polydispersity index and colloidal stability. The association efficiency of the drug ranged between 35 and 50%, which for a poorly soluble drug is a good achievement, and in formulations with pH 6.7 this parameter increased significantly. A robust ionic liquid-polymer nanoparticle hybrid system was obtained in the presence of polyvinyl alcohol at 2% (w/v), demonstrating their potential to incorporate higher amounts of poorly soluble drugs. The developed hybrid systems may ultimately enhance the therapy of several health problems increasing the quality of life of patients treated with this type of drugs.
Anticancer activity of rutin and its combination with ionic liquids on renal cells Rita Caparica, Ana Júlio, Maria Eduarda Machado Araújo, André Rolim Baby, Pedro Fonte, et al. Biomolecules, 2020 The renal cell carcinoma (RCC) is the most common type of kidney cancer. Identifying novel and more effective therapies, while minimizing toxicity, continues to be fundamental in curtailing RCC. Rutin, a bioflavonoid widely found in nature, has shown promising anticancer properties, but with limited applicability due to its poor water solubility and pharmacokinetics. Thus, the potential anticancer effects of rutin toward a human renal cancer cell line (786-O), while considering its safety in Vero kidney cells, was assessed, as well as the applicability of ionic liquids (ILs) to improve drug delivery. Rutin (up to 50 µM) did not show relevant cytotoxic effects in Vero cells. However, in 786-O cells, a significant decrease in cell viability was already observed at 50 µM. Moreover, exposure to rutin caused a significant increase in the sub-G1 population of 786-O cells, reinforcing the possible anticancer activity of this biomolecule. Two choline-amino acid ILs, at non-toxic concentrations, enhanced rutin’s solubility/loading while allowing the maintenance of rutin’s anticancer effects. Globally, our findings suggest that rutin may have a beneficial impact against RCC and that its combination with ILs ensures that this poorly soluble drug is successfully incorporated into ILs–nanoparticles hybrid systems, allowing controlled drug delivery.
