Showing: 10 from total: 26 publications
1. Marine waste derived carbon materials for use as sulfur hosts for Lithium-Sulfur batteries
Forde, R ; State, S ; Costa, R ; Enache, LB ; Enachescu, M ; Pereira, CM ; Geaney, H ; Mcnulty, D ; Brandao, ATSC ; Bowman, D ; Ryan, KM
in BIORESOURCE TECHNOLOGY, 2024, ISSN: 0960-8524,  Volume: 406, 
Article,  Indexed in: crossref, scopus, wos 
Abstract Lithium-sulfur batteries are a promising alternative to lithium-ion batteries as they can potentially offer significantly increased capacities and energy densities. The ever-increasing global battery market demonstrates that there will be an ongoing demand for cost effective battery electrode materials. Materials derived from waste products can simultaneously address two of the greatest challenges of today, i.e., waste management and the requirement to develop sustainable materials. In this study, we detail the carbonisation of gelatin from blue shark and chitin from prawns, both of which are currently considered as waste biproducts of the seafood industry. The chemical and physical properties of the resulting carbons are compared through a correlation of results from structural characterisation techniques, including electron imaging, X-ray diffraction, Raman spectroscopy and nitrogen gas adsorption. We investigated the application of the resulting carbons as sulfur-hosting electrode materials for use in lithium-sulfur batteries. Through comprehensive electrochemical characterisation, we demonstrate that value added porous carbons, derived from marine waste are promising electrode materials for lithium-sulfur batteries. Both samples demonstrated impressive capacity retention when galvanostatically cycled at a rate of C/5 for 500 cycles. This study highlights the importance of looking towards waste products as sustainable feeds for battery material production.

2. γ-Conglutin Immunoreactivity Is Differently Affected by Thermal Treatment and Gastrointestinal Digestion in Lupine Species
Villa, C ; Carriço-Sá, B ; Teixeira, CSS ; Dias, C ; Costa, R ; Pereira, CM ; Mafra, I ; Costa, J
in FOODS, 2024, ISSN: 2304-8158,  Volume: 13, 
Article,  Indexed in: crossref, scopus, wos 
Abstract Lupine is a legume commonly used in human diet as a functional food due to its high nutritional content and important technological properties. However, its consumption can lead to the manifestation of adverse immunological reactions, posing significant health issues in sensitized/allergic patients. This work aims to investigate the effect of food processing combined with simulated gastrointestinal (GI) digestion on the immunoreactivity of lupine gamma-conglutin. Model foods of wheat pasta containing 35% of lupine flour (Lupinus albus, L. luteus, and L. angustifolius) were prepared and submitted to a boiling process. The proteins were extracted and their profiles characterized by SDS-PAGE. Simulated GI digestion was performed on thermally treated pasta using the INFOGEST harmonized digestion protocol 2.0. The IgG binding capacity of gamma-conglutin was assessed by immunoblotting in non-reducing conditions and indirect ELISA with specific antibodies. Results demonstrate that the boiling treatment affected the immunoreactivity of the three lupine species differently. Simulated GI digestion led to extensive destruction of the protein structure, more significant in the intestinal phase, reducing but not abolishing the IgG affinity to gamma-conglutin and its potential presentation to immunocompetent cells. This information can offer valuable insights to the food industry for developing food formulations with reduced allergenic properties.

3. In-situ electrochemically synthesized artificial Gly m TI antibody for soybean allergen quantification in complex foods
Dias, C ; Fernandes, D ; Costa, J ; Villa, C ; Moreira, P ; Brandão, TSC ; Mafra, I ; Silva, A ; Pereira, M ; Costa, R
in ANALYTICA CHIMICA ACTA, 2024, ISSN: 0003-2670,  Volume: 1332, 
Article,  Indexed in: crossref, scopus, wos 
Abstract Biosensors, especially those designed for detecting food allergens like Gly m TI in soybean, play a crucial role in safeguarding individuals who suffer from adverse food allergies, extending to both individual well-being and broader public health considerations. Furthermore, their integration into food production and monitoring processes aids in compliance with regulatory standards, reducing the incidence of allergen-related recalls and protecting vulnerable populations. Technological advancements in biosensor development, such as increased portability, real-time monitoring capabilities, and user-friendly interfaces, have expanded their practical applications, making them indispensable in various settings, including manufacturing plants, food service establishments, and even at-home use by consumers. For the first time, a biosensor targeting the Gly m TI allergen based on molecularly imprinted polymer (MIP) technology was developed to detect/quantify soybean in complex food matrices and effectively address the detection challenges of complex and processed foods. The Gly m TI-MIP underwent a thorough validation process using anti-Gly m TI IgG raised as a polyclonal response to the trypsin inhibitor. Gly m TI-MIP was successfully tested across a range of food matrices, including tree nuts (e.g., peanuts, walnuts, and hazelnuts) and legumes (e.g., lentils, beans, and lupine), presenting minimal cross-reactivity with lupine and walnut. The innovative approach provided a linear response in the 1 ag mL(-1) - 10 mu g mL(-1) range, with a LOD<1 ag mL(-1). Applying the Gly m TI-MIP sensor to complex model foods allowed to detect 0.1 mg kg(-1) (0.00001 %) of soybean protein isolate in biscuits, ham, and sausages before and after the respective thermal treatments. The innovative biosensor can significantly improve food safety protocols by addressing the complexities of tracing allergens in processed and unprocessed food products. By ensuring rigorous allergen control, these biosensors may support global food trade compliance with international safety standards, boost consumer confidence, and promote transparency in food labeling, ultimately contributing to a safer food supply chain.

4. Characterization of Carbon Nanomaterials Dispersions: Can Metal Decoration of MWCNTs Improve Their Physicochemical Properties?
Brandao, ATSC ; Rosoiu, S ; Costa, R ; Silva, AF ; Anicai, L ; Enachescu, M ; Pereira, CM
in NANOMATERIALS, 2022, Volume: 12, 
Article,  Indexed in: crossref, scopus, wos 
Abstract A suitable dispersion of carbon materials (e.g., carbon nanotubes (CNTs)) in an appropriate dispersant media, is a prerequisite for many technological applications (e.g., additive purposes, functionalization, mechanical reinforced materials for electrolytes and electrodes for energy storage applications, etc.). Deep eutectic solvents (DES) have been considered as a promising "green" alternative, providing a versatile replacement to volatile organic solvents due to their unique physical-chemical properties, being recognized as low-volatility fluids with great dispersant ability. The present work aims to contribute to appraise the effect of the presence of MWCNTs and Ag-functionalized MWCNTs on the physicochemical properties (viscosity, density, conductivity, surface tension and refractive index) of glyceline (choline chloride and glycerol, 1:2), a Type III DES. To benefit from possible synergetic effects, AgMWCNTs were prepared through pulse reverse electrodeposition of Ag nanoparticles into MWCNTs. Pristine MWCNTs were used as reference material and water as reference dispersant media for comparison purposes. The effect of temperature (20 to 60 degrees C) and concentration on the physicochemical properties of the carbon dispersions (0.2-1.0 mg cm(-3)) were assessed. In all assessed physicochemical properties, AgMWCNTs outperformed pristine MWCNTs dispersions. A paradoxical effect was found in the viscosity trend in glyceline media, in which a marked decrease in the viscosity was found for the MWCNTs and AgMWCNTs materials at lower temperatures. All physicochemical parameters were statistically analyzed using a two-way analysis of variance (ANOVA), at a 5% level of significance.

5. Electrochemical and optical biosensing platforms for the immunorecognition of hazelnut Cor a 14 allergen
Costa, R ; Costa, J ; Sagastizábal, I ; Brandao, ATSC ; Moreira, P ; Mafra, I ; Silva, AF ; Pereira, CM
in FOOD CHEMISTRY, 2021, ISSN: 0308-8146,  Volume: 361, 
Article,  Indexed in: crossref, scopus, unpaywall, wos 
Abstract Two immunosensors were advanced to target hazelnut Cor a 14 based on electrochemical and optical transduction. Both approaches were developed with two types of custom-made antibodies, namely anti-Cor a 14 IgG (rabbit) and anti-Cor a 14 IgY (hen's egg) targeting the Cor a 14 allergen. Antibody immobilisation was performed via EDC/NHS onto disposable screen-printed electrodes. The detection limit (LOD) of the electrochemical immunoassay for Cor a 14 was 5-times lower than the optical, being down to 0.05 fg mL-1 with a dynamic range of 0.1 fg mL-1 to 0.01 ng mL-1. Antibody selectivity was verified against non-target 2S albumins (potential crossreactive plant species). Anti-Cor a 14 IgY exhibited the best specificity, presenting minor cross-reactivity with peanut/walnut. Preliminary results of the application of anti-Cor a 14 IgY electrochemical immunosensor to incurred foods established a LOD of 1 mg kg- 1 of hazelnut in wheat (0.16 mg kg- 1 hazelnut protein).

6. Sustainable Preparation of Nanoporous Carbons via Dry Ball Milling: Electrochemical Studies Using Nanocarbon Composite Electrodes and a Deep Eutectic Solvent as Electrolyte
Brandao, ATSC ; Costa, R ; Silva, AF ; Pereira, CM
in NANOMATERIALS, 2021, ISSN: 2079-4991,  Volume: 11, 
Article,  Indexed in: crossref, scopus, wos 
Abstract The urgent need to reduce the consumption of fossil fuels drives the demand for renewable energy and has been attracting the interest of the scientific community to develop materials with improved energy storage properties. We propose a sustainable route to produce nanoporous carbon materials with a high-surface area from commercial graphite using a dry ball-milling procedure through a systematic study of the effects of dry ball-milling conditions on the properties of the modified carbons. The microstructure and morphology of the dry ball-milled graphite/carbon composites are characterized by BET (Brunauer-Emmett-Teller) analysis, SEM (scanning electron microscopy), ATR-FTIR (attenuated total reflectance-Fourier transform infrared spectroscopy) and Raman spectroscopy. As both the electrode and electrolyte play a significant role in any electrochemical energy storage device, the gravimetric capacitance was measured for ball-milled material/glassy carbon (GC) composite electrodes in contact with a deep eutectic solvent (DES) containing choline chloride and ethylene glycol as hydrogen bond donor (HBD) in a 1:2 molar ratio. Electrochemical stability was tracked by measuring charge/discharge curves. Carbons with different specific surface areas were tested and the relationship between the calculated capacitance and the surface treatment method was established. A five-fold increase in gravimetric capacitance, 25.27 F center dot g(-1) (G40) against 5.45 F center dot g(-1), was found for commercial graphene in contact with DES. Optimal milling time to achieve a higher surface area was also established.

7. Characterization and electrochemical studies of MWCNTs decorated with Ag nanoparticles through pulse reversed current electrodeposition using a deep eutectic solvent for energy storage applications
Brandao, ATSC ; Rosoiu, S ; Costa, R ; Lazar, OA ; Silva, AF ; Anicai, L ; Pereira, CM ; Enachescu, M
in JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T, 2021, ISSN: 2238-7854,  Volume: 15, 
Article,  Indexed in: crossref, scopus, wos 
Abstract Carbon nanotubes (CNTs) are receiving special attention due to their remarkable thermal, electrical, and mechanical properties. The present work reports an innovative synthesis procedure to decorate MWCNTs with silver nanoparticles (Ag-NPs) via pulsed reverse deposition technique using a deep eutectic solvent (DES) based on choline chloride and glycerol as an electrolyte at room temperature, not requiring any previous surface modification of MWCNTs. MWCNTs decorated with Ag-NPs disclose a significant enhancement of their electrochemical performance as demonstrated by the increase of electrode stability and specific capacitance. Electrochemical characterization of the composite material was performed using cyclic voltammetry and charge/discharge curves, achieving a specific capacitance up to 28.50 F. g-1, against 4.70 F. g-1 for the commercial MWCNTs in a three-electrode system. Retention of the specific capacitance up to 99% for the Ag-MWCNTs composites compared with a value of 78% for electrodes modified with commercial MWCNTs. The Ag-MWCNTs composites were characterized through SEM/EDX analysis, ultrahighresolution STEM, in which the Z - Contrast image was collected, and Raman analysis to prove the successful attachment of the Ag-NPs to the MWCNTs surface. AFM was performed to evaluate the conductivity of the composites. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

8. Ordering and Nonideality of Air-Ionic Liquid Interfaces in Surface Second Harmonic Generation
Costa, R ; Pereira, CM ; Silva, AF ; Brevet, PF ; Benichou, E
in JOURNAL OF PHYSICAL CHEMISTRY B, 2020, ISSN: 1520-6106,  Volume: 124, 
Article,  Indexed in: crossref, scopus, wos 
Abstract The air-ionic liquid interface for a series of ionic liquids involving imidazolium cations [C(n)mim] with different alkyl chain lengths (n = 2, 4, 6, 8, 10, and 12) and the same [NTf2] imide anion has been studied by polarization-resolved second harmonic generation (SHG). An increase as a function of the alkyl chain length of the orientational parameter reveals the increasing ordering of the air-pure ionic liquid interfaces although it is not possible to disentangle the change in mean tilt angle from a change in the tilt angle probability distribution width. Besides, the study of the air-mixed ([C(12)mim])(x)([C(2)mim])(1-x)[NTf2] ionic liquid interface clearly demonstrates the interfacial nonideality of the mixed ionic liquids. The long alkyl chain cation perturbs the interface as seen from the orientational parameter and displaces the short alkyl chain one for bulk mixture contents as low as 10%. At higher long alkyl chain cation bulk mixture contents, the interface behaves close to a pure long alkyl chain ionic liquid.

9. 5. Ionic liquids at electrified interfaces for advanced energy/charge storage applications
Costa, R ; Pereira, CM ; Silva, AF
in Ionic Liquids, 2019,
Book Chapter,  Indexed in: crossref 

10. Molecularly imprinted polymer SPE sensor for analysis of CA-125 on serum
Rebelo, TSCR ; Costa, R ; Brandao, ATSC ; Silva, AF ; Sales, MGE ; Pereira, CM
in ANALYTICA CHIMICA ACTA, 2019, ISSN: 0003-2670,  Volume: 1082, 
Article,  Indexed in: crossref, scopus, wos 
Abstract Considering the high incidence level and mortality rate of ovarian cancer, particularly among the European female population, the carbohydrate antigen 125 (CA-125) was selected as the protein target for this study for the development of a MIP-based biosensor. This work presents the development of molecular imprinting polymers (MIPs) on gold electrode surface for CA-125 biomarker recognition. The preparation of the CA-125 imprinting was obtained by electropolymerization of pyrrole (Py) monomer in a gold electrode using cyclic voltammetry (CV) in order to obtain highly selective materials with great molecular recognition capability. The quantification of CA-125 biomarker was made through the comparison of two methods: electrochemical (square wave voltammetry -SWV) and optical transduction (surface plasmon resonance -SPR). SWV has been widely used in biological molecules analysis since it is a fast and sensitive technique. In turn, SPR is a non-destructive optical technique that provides high-quality analytical data of CA-125 biomarker interactions with MIP. Several analytical parameters, such as sensitivity, linear response interval, and detection limit were determined to proceed to the performance evaluation of the electrochemical and optical transduction used in the development of the CA-125 biosensor. The biosensor based in the electrochemical transduction was the one that presented the best analytical parameters, yielding a good selectivity and a detection limit (LOD) of 0.01 U/mL, providing a linear concentration range between 0.01 and 500 U/mL. This electrochemical biosensor was selected for the study and it was successfully applied in the CA-125 analysis in artificial serum samples with recovery rates ranging from 91 to 105% with an average relative error of 5.8%.