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Doxorubicin delivery performance of superparamagnetic carbon multi-core shell nanoparticles: pH dependence, stability and kinetic insight

Publication . Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Sayuri Berberich, Thais; Inglez, Simone Delezuk; Bertão, Ana Raquel; Çaha, Ihsan; Deepak, Francis Leonard; Bañobre-López, Manuel; Gomes, Helder

In the past decade, magnetic nanoparticles (MNPs) have been among the most attractive nanomaterials used in different fields, such as environmental and biomedical applications. The possibility of designing nanoparticles with different functionalities allows for advancing the biomedical applications of these materials. Additionally, the magnetic characteristics of the nanoparticles enable the use of magnetic fields to drive the nanoparticles to the desired sites of delivery. In this context, the development of new MNPs in new approaches for drug delivery systems (DDSs) for cancer treatment has increased. However, the synthesis of nanoparticles with high colloidal stability triggered drug delivery, and good biocompatibility remains a challenge. Herein, multi-core shell MNPs functionalized with Pluronic ® F-127 were prepared and thoroughly characterized as drug carriers for doxorubicin delivery. The functionalized nanoparticles have an average size of 17.71 ± 4.2 nm, high water colloidal stability, and superparamagnetic behavior. In addition, the nanoparticles were able to load 936 μg of DOX per mg of functionalized nanomaterial. Drug release studies at different pH values evidenced a pH-triggered DOX release effect. An increase of 62% in cumulative drug release was observed at pH simulating tumor endosome/lysosome microenvironments (pH 4.5) compared to physiological conditions (pH 7.4). In addition, an innovative dynamic drug delivery study was performed as a function of pH. The results from this test confirmed the pH-induced doxorubicin release capability of carbon multi-core shell MNPs. The validity of traditional kinetic models to fit dynamic pH-dependent drug release was also studied for predictive purposes.

2022Journal article

Open access

Simultaneous removal of o-and p-nitrophenol from contaminated water by wet peroxide oxidation using carbon-coated magnetic ferrite as catalyst

Publication . Dias, Arnaldo; Silva, Adriano S.; Silva, Ana P. F.; Roman, Fernanda; Díaz de Tuesta, Jose Luis; Oliveira, Jéssica; Ferrari, Ana M.; Lenzi, Giane G.; Gomes, Helder; Oliveira, Jessíca

Groundwater is the most common source of drinking water worldwide and is currently facing contamination problems with the discharge of pollutants into aquatic systems through different means, namely through municipal, industrial and agricultural activities. Contaminants, such as herbicides, pharmaceuticals, phenolic compounds and personal care products are not removed by conventional treatments from wastewater treatment plants, leading to their accumulation in the environment. In this regard, o-nitrophenol (o-NP) and p-nitrophenol (p-NP), commonly used as raw materials in chemical and pharmaceutical engineering, represent a severe risk to humans and aquatic life, leading to the necessity to properly treat wastewaters containing these contaminants before discharge into the aquatic environment. Catalytic wet peroxide oxidation (CWPO) showed promising results for removing nitrophenols from wastewater in previous works. In this technology, H2O2 is used as an oxidant, and its interaction with a suitable catalyst leads to the formation of hydroxyl radicals under determined conditions already established in literature (pH and temperature have a strong influence) [1]. Typical catalysts employed have a transition metal in its structure. Carbon-based catalysts also have activity in this technology, mostly ascribed to the electronic properties of the carbonaceous surface. Furthermore, carbon-coated metal oxide materials (hybrid) have also demonstrated potential applications in CWPO. Those structures combine carbon and metal activities with the advantage of protecting the metal core from leaching, increasing the efficiency and stability of the catalysts.

2022Conference object

Open access

Hybrid multi-core shell magnetic nanoparticles for wet peroxide oxidation of paracetamol: application in synthetic and real matrices

Publication . Silva, Adriano S.; Roman, Fernanda; Dias, Arnaldo; Díaz de Tuesta, Jose Luis; Narcizo, Alexandre; Silva, Ana P. F.; Çaha, Ihsan; Deepak, Francis Leonard; Bañobre-López, Manuel; Ferrari, Ana M.; Gomes, Helder

Clean water availability is becoming a matter of global concern in the last decades. The responsible entities for wastewater treatment do not have the proper facilities to deal with a wide range of pollutants. Special attention should be given to emerging contaminants, whose presence in water bodies may cause adverse effects on the aquatic ecosystem and human health. Most studies in the literature do not consider the development of their solution in real matrices, which can hinder the applicability of the explored alternative in the real scenario. Therefore, in this work, we demonstrate the applicability of hybrid magnetic nanoparticles for removing paracetamol (PCM) from simulated and real matrices by catalytic wet peroxide oxidation (CWPO). To achieve carbon coating, the nanoparticles were prepared via the traditional route (resorcinol/formaldehyde, CoFe@CRF). A new methodology was also considered for synthesizing thin-layered carbon-coated magnetic nanoparticles (phloroglucinol/ glyoxalic acid, CoFe@CPG). TEM images revealed a multi-core shell structure formation, with an average carbon layer size of 7.8 ± 0.5 and 3.2 ± 0.3 nm for resorcinol/formaldehyde and phloroglucinol/ glyoxalic acid methodology, respectively. Screening the materials’ activity for PCM oxidation by CWPO revealed that the nanoparticle prepared by phloroglucinol/glyoxalic acid methodology has higher performance for the degradation of PCM, achieving 63.5% mineralization after 24 h of reaction, with similar results for more complex matrices. Iron leaching measured at the end of all reactions has proven that the carbon layer protects the core against leaching.

2023Journal article

Open access

Selective denitrification of a simulated oily wastewater using Janus-structured carbon nanotubes

Publication . Roman, Fernanda; Sanches, Flávia Kim; Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Marin, Pricila; Machado, Bruno; Serp, Philippe; Silva, Adrián; Faria, Joaquim; Gomes, Helder

Carbon nanotubes (CNTs) bearing a Janus-like structure were synthesized by chemical vapor deposition considering ethylene and acetonitrile as carbon and nitrogen sources. The developed materials were applied as catalyst in the oxidation of 4-nitrophenol (4-NP) dissolved in a biphasic medium (water/2,2,4-trimeylpentane) simulating a contaminated oily wastewater. The CNT prepared using both ethylene and acetonitrile precursors shows a Janus-structure, leading to the highest abatement of 4-NP as well as to the highest removal of TOC, proving to be an alternative towards the removal of lipophilic pollutants from oily effluents, allowing to reclaim the oily phase.

2022Conference object

Open access

Dynamic waste collection strategy to optimize routes using open-source tool