Bathing water quality standards are based on international standards and legislations. However, in Europe, only the microbiological parameters are to be accomplished. Recent research has focused on chemical indicators that can determine human fecal contaminants in water. Therefore, the suitability of caffeine as a chemical marker of seawater pollution in the north Portuguese coastal area in the Atlantic Ocean during the bathing season was assessed in this study. The quality of water from the coasts of five cities was monitored. 101 seawater samples were collected from 14 beaches, and their water quality was classified as sufficient, good, and excellent. Caffeine was detected in all samples in concentration range of 18 to 525ng/L. The highest average concentration of caffeine was found in seawater samples collected in July from beaches classified as having sufficient water quality, which were located in cities with high population density and high tourist affluence. ; info:eu-repo/semantics/publishedVersion
In cancer, screening and early detection are critical for the success of the patient's treatment and to increase the survival rate. The development of analytical tools for non‐invasive detection, through the analysis of cancer biomarkers, is imperative for disease diagnosis, treatment and follow‐up. Tumour biomarkers refer to substances or processes that, in clinical settings, are indicative of the presence of cancer in the body. These biomarkers can be detected using biosensors, that, because of their fast, accurate and point of care applicability, are prominent alternatives to the traditional methods. Moreover, the constant innovations in the biosensing field improve the determination of normal and/or elevated levels of tumour biomarkers in patients' biological fluids (such as serum, plasma, whole blood, urine, etc.). Although several biomarkers (DNA, RNA, proteins, cells) are known, the detection of proteins and circulating tumour cells (CTCs) are the most commonly reported due to their approval as tumour biomarkers by the specialized entities and commonly accepted for diagnosis by medical and clinical teams. Therefore, electrochemical immunosensors and cytosensors are vastly described in this review, because of their fast, simple and accurate detection, the low sample volumes required, and the excellent limits of detection obtained. The biosensing strategies reported for the six most commonly diagnosed cancers (lung, breast, colorectal, prostate, liver and stomach) are summarized and the distinct phases of the sensors' constructions (surface modification, antibody immobilization, immunochemical interactions, detection approach) and applications are discussed. ; Maria Freitas is grateful to FCT‐Fundação para a Ciência e a Tecnologia for her PhD grant (SFRH/BD/111942/2015), financed by POPH‐QREN‐Tipologia 4.1‐Formaçãpo Avançada, subsidized by Fundo Social Europeu and Ministério da Ciência, Tecnologia e Ensino Superior. This work received financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT) through project UID/QUI/50006/2013. ; info:eu-repo/semantics/publishedVersion
Screening and early diagnosis are crucial to increase the success of cancer patients' treatments and improve the survival rate. To contribute to this success, distinct electrochemical immunosensing platforms were developed for the analysis of the ExtraCellular Domain of the Human Epidermal growth factor Receptor 2 (HER2‐ECD) through sandwich assays on nanomaterial‐modified screen‐printed carbon electrodes (SPCEs). The most promising platforms showed to be SPCEs modified with (i) gold nanoparticles (AuNPs) and (ii) multiwalled carbon nanotubes combined with AuNPs. The antibody‐antigen interaction was detected using a secondary antibody labelled with alkaline phosphatase and 3‐indoxyl phosphate and silver ions as the enzymatic substrate. The electrochemical signal of the enzymatically generated metallic silver was recorded by linear sweep voltammetry. Under the optimized conditions, linear calibration plots were obtained between 7.5 and 50 ng/mL and the total assay time was 2 h 20 min, achieving LODs of 0.16 ng/mL (SPCE‐MWCNT/AuNP) and 8.5 ng/mL (SPCE‐AuNP), which are well below the established cut‐off value of 15 ng/mL for this cancer biomarker. ; Maria Freitas is grateful to FCT‐Fundação para a Ciência e a Tecnologia for her PhD grant (SFRH/BD/111942/2015), financed by POPH‐QREN‐Tipologia 4.1‐Formação Avançada, subsidized by Fundo Social Europeu and Ministério da Ciência, Tecnologia e Ensino Superior. This work received financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT) through project UID/QUI/50006/2013. ; info:eu-repo/semantics/publishedVersion
AbstractThe application of sewage sludge (SS) in agriculture, as an alternative to manufactured fertilizers, is current practice worldwide. However, as wastewater is collected from households, industries, and hospitals, the resulting sludge could contaminate land with creeping levels of pharmaceuticals, pesticides, heavy metals, polycyclic aromatic hydrocarbons, and microplastics, among others. Thus, the sustainable management of SS requires the development of selective methods for the identification and quantification of pollutants, preventing ecological and/or health risks. This study presents a thorough evaluation of emerging and priority micropollutants in SS, through the lens of environmental insights, by developing and implementing an integrated analytical approach. A quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method, coupled with gas chromatography and liquid chromatography, was optimized for the determination of 42 organic compounds. These include organophosphorus pesticides, organochlorine pesticides, pyrethroid pesticides, organophosphate ester flame retardants, polybrominated diphenyl ethers, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons. The optimization of the dispersive-solid phase for clean-up, combined with the optimization of chromatographic parameters, ensured improved sensitivity. Method validation included assessments for recovery, reproducibility, limit of detection (LOD), and limit of quantification (LOQ). Recoveries ranged from 59.5 to 117%, while LODs ranged from 0.00700 to 0.271 µg g-1. Application of the method to seven SS samples from Portuguese wastewater treatment plants revealed the presence of sixteen compounds, including persistent organic pollutants. The quantification of α-endosulfan, an organochlorine pesticide, was consistently observed in all samples, with concentrations ranging from 0.110 to 0.571 µg g-1. Furthermore, the study encompasses the analysis of agronomic parameters, as well as the mineral and metal content in SS samples. The study demonstrates that the levels of heavy metals comply with legal limits. By conducting a comprehensive investigation into the presence of micropollutants in SS, this study contributes to a deeper understanding of the environmental and sustainable implications associated with SS management. Graphical Abstract
This work characterizes the dimension and the exceptionality of 2017 large- and mega-fires that occurred in the center region of Portugal through the assessment of their impact on the ambient levels of particulate matter (PM10 and PM2.5), retrieved from local monitoring stations, and the associated public health risks. PM10 and PM2.5 concentrations were increased during the occurrence of large fires and megafires, with daily concentrations exceeding the European/national guidelines in 7–14 and 1–12 days of 2017 (up to 704 µg/m3 for PM10 and 46 µg/m3 for PM2.5), respectively. PM10 concentrations were correlated with total burned area (0.500 0.05) and with monthly total burned area/distance2 (0.500 0.05). The forest fires of 2017 took the life of 112 citizens. A total of 474 cases of hospital admissions due to cardiovascular diseases and 3524 cases of asthma incidence symptoms per 100,000 individuals at risk were assessed due to exposure to 2017 forest fires. Real-time and in situ PM methodologies should be combined with protection action plans to reduce public health risks. Portuguese rural stations should monitor other health-relevant pollutants (e.g., carbon monoxide and volatile organic compounds) released from wildfires to allow performing more robust and comprehensive measurements that will allow a better assessment of the potential health risks for the exposed populations. ; This work was financially supported by European Union (FEDER funds through COMPETE) and National Funds (Fundação para a Ciência e Tecnologia) [projects UIDB/50006/2020, UID/EQU/00511/2013-LEPABE], by the FCT/MEC with national funds and cofounded by FEDER in the scope of the P2020 Partnership Agreement. This study was also supported by the project "PCIF/SSO/0017/2018- A panel of (bio)markers for the surveillance of firefighter's health and safety", funded by Portuguese National Funds through FCT—Fundação para a Ciência e Tecnologia. M. Oliveira thanks to FCT/MCTES for the CEEC-Individual 2017 Program Contract [CEECIND/03666/2017]. ; info:eu-repo/semantics/publishedVersion
Histamine is an important biogenic amine because of its role in immune responses and the regulation of physiological functions. It is also used as a food freshness indicator, so its maximum concentration in fish is legally regulated. Although several robust and sensitive methods for histamine detection are already available, it continues to be a challenge to develop simple and portable devices that allow rapid histamine screening at any point of the fish production chain. Thus, in this work, a simple, miniaturized and low-cost sensor for histamine analysis was developed. The construction of the sensor only takes 30 min and consists of the immobilization of the enzyme diamine oxidase on the surface of a screen-printed carbon electrode by cross-linking. The quantification of histamine was achieved by chronoamperometry (+ 0.2V,120 s) using hexacyanoferrate (III) as a redox mediator. This selective sensor provided a low limit of detection (0.97 mg L−1) and accurate and precise results and was successfully applied to the analysis of spiked tuna and mackerel extracts,obtaining recovery values of 99–100%. Moreover, the sensor shows good stability, maintaining 87.7% of its initial signalafter 35 days. ; This work was supported by UID/QUI/50006/2019 with funding from the Fundação para a Ciência e a Tecnologia (FCT)/the Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) through national funds. The authors also thank FCT and the EU for funding through the projects: FOODnanoHEALTH - Qualidade e Segurança Alimentar –uma abordagem (nano)tecnológica (Portugal2020, Norte-01-0145-FEDER-000011), FishBioSensing - Portable electrochemical (bio)sensing devices for safety and quality assessment of fishery products (02/SAICT/2016, POCI-01-0145-FEDER-023817), PTDC/ASP-PES/29547/2017 –CECs(Bio)Sensing - (Bio)sensors for assessment of contaminants of emerging concern in fishery commodities, (POCI-01-0145-FEDER-029547) and PTDC/QUI-QAN/30735/2017 –TracAllerSens - Electrochemical sensors for the detection and quantification of trace amounts of allergens in food products (POCI-01-0145-FEDER-030735), supported by national funds by FCT / MCTES and co-supported by Fundo Europeu de esenvolvimento Regional (FEDER) through COMPETE 2020 –Programa Operacional Competitividade e Internacionalização. E. Costa-Rama thanks the Government of Principado de Asturias and Marie Curie-Cofund Actions for the post-doctoral grant "Clarín-Cofund"ACA17-20. R. Torre is grateful for her PhD grant from FCT (SFRH/BD/143753/2019), fi- nanced by POPH–QREN–Tipologia 4.1–Formação Avançada, and subsidized by FSE and MCTES ; info:eu-repo/semantics/publishedVersion
According to the recent statistics, Salmonella is still an important public health issue in the whole world. Legislated reference methods, based on counting plate methods, are sensitive enough but are inadequate as an effective emergency response tool, and are far from a rapid device, simple to use out of lab. An overview of the commercially available rapid methods for Salmonella detection is provided along with a critical discussion of their limitations, benefits and potential use in a real context. The distinguished potentialities of electrochemical biosensors for the development of rapid devices are highlighted. The state-of-art and the newest technologic approaches in electrochemical biosensors for Salmonella detection are presented and a critical analysis of the literature is made in an attempt to identify the current challenges towards a complete solution for Salmonella detection in microbial food control based on electrochemical biosensors. ; This work received financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT, Fundação para a Ciência e Tecnologia) through project UID/QUI/50006/2013. Nádia Silva is gratefully to FCT grant SFRH/BD/112414/2015, financed by POPH–QREN–Tipologia 4.1–Formação Avançada, subsidized by Fundo Social Europeu and Ministério da Ciência, Tecnologia e Ensino Superior. ; info:eu-repo/semantics/publishedVersion
Food spoilage is caused by the development of microorganisms, biogenic amines, and other harmful substances, which, when consumed, can lead to different health problems. Foodborne diseases can be avoided by assessing the safety and freshness of food along the production and supply chains. The routine methods for food analysis usually involve long analysis times and complex instrumentation and are performed in centralized laboratories. In this context, sensors based on screen-printed electrodes (SPEs) have gained increasing importance because of their advantageous characteristics, such as ease of use and portability, which allow fast analysis in point-of-need scenarios. This review provides a comprehensive overview of SPE-based sensors for the evaluation of food safety and freshness, focusing on the determination of bacteria and biogenic amines. After discussing the characteristics of SPEs as transducers, the main bacteria, and biogenic amines responsible for important and common foodborne diseases are described. Then, SPE-based sensors for the analysis of these bacteria and biogenic amines in food samples are discussed, comparing several parameters, such as limit of detection, analysis time, and sample type. ; This work was supported by UIDB/50006/2020 and UIDP/50006/2020 with funding from the Fundação para a Ciência e a Tecnologia (FCT)/the Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) through national funds. The authors also thank FCT and the EU for funding through the projects: FishBioSensing—Portable electrochemical (bio)sensing devices for safety and quality assessment of fishery products (02/SAICT/2016, POCI-01-0145-FEDER-023817), PTDC/QUI-QAN/30735/2017—TracAllerSens—Electrochemical sensors for the detection and quantification of trace amounts of allergens in food products (POCI-01-0145-FEDER-030735), and PTDC/ASP-PES/29547/2017—CECs(Bio)Sensing—(Bio)sensors for assessment of contaminants of emerging concern in fishery commodities (POCI-01-0145-FEDER-029547), supported by national funds by FCT/MCTES and co-supported by Fundo Europeu de Desenvolvimento Regional (FEDER) through COMPETE 2020—Programa Operacional Competitividade e Internacionalização. E. Costa-Rama thanks the Government of Principado de Asturias and Marie Curie-Cofund Actions for the post-doctoral grant "Clarín-Cofund" ACA17-20. R. Torre is grateful to FCT for her PhD grant (SFRH/BD/143753/2019), financed by POPH–QREN–Tipologia 4.1–Formação Avançada, subsidized by FSE and MCTES. ; info:eu-repo/semantics/publishedVersion
Chayote (Sechium edule) has gained widespread consuming acceptance and recognized by its nutritional and bio-functional properties. The present review surveys and describes the current findings about the nutritional, phytochemical and pharmacological properties of chayote and identifies opportunities for further research. It also discusses chayote's versatile utility in nutrition, as a functional ingredient in food, cosmetic and pharmaceutical industries, as well as in nanotechnology and biotechnological processes. It was concluded that although the pharmacological properties of chayote are currently well-established, only a few reports have been conducted on the isolation and identification of individual chemical constituents, and similarly, only a few in vivo studies have been conducted to assess their biological efficacy. In addition, the valorisation of the underutilized chayote by-products can be an important aspect in waste management from both economic and environmental standpoints. Thus, the recovery and utilization of valuable compounds from chayote is an important challenge for scientists. ; This work was supported by European Union (FEDER funds through COMPETE) and National Funds (Fundação para a Ciência e a Tecnologia) through the project UID/QUI/50006/2013. ; info:eu-repo/semantics/publishedVersion
The extracellular domain of the human epidermal growth factor receptor 2 (HER2-ECD) is a protein breast cancer biomarker. Its quantification in peripheral blood could provide an important contribution to diagnostics and patient follow-up. In this work an electrochemical molecularly imprinted polymer (MIP) sensor for the quantification of HER2-ECD was developed. The MIP was electropolymerized by cyclic voltammetry using a solution containing phenol and HER2-ECD on a screen-printed gold electrode (AuSPE). The sensor was characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The analysis of HER2-ECD was performed by differential pulse voltammetry using ([Fe(CN)6]3−/4−as redox probe. The linear range was established in the concentration interval from 10 to 70 ng/mL HER2-ECD, with a limit of detection of 1.6 ng/L and a limit of quantification of 5.2 ng/mL. Through the analysis of other protein biomarkers, the MIP sensor was found to be selective. Furthermore, these proteins did not interfere in the analysis of the selected biomarker. The developed sensor was used for the analysis of spiked human serum samples, providing adequate recovery values and precise results. The outcomes of this study indicate that the developed MIP sensor could be useful in the non-invasive analysis of HER2-ECD in breast cancer patients. ; Maria Freitas is grateful to FCT (Fundação para a Ciência e a Tecnologia) for her PhD grant (SFRH/BD/111942/2015). Patrícia Rebelo is grateful to FCT (Fundação para a Ciência e a Tecnologia) for her PhD grant (SFRH/BD/132384/2017). João Pacheco is grateful to FCT for his Postdoc. grant (SFRH/BPD/101419/2014), financed by POPH-QREN-Tipologia 4.1-Formação Avançada, subsidized by Fundo Social Europeu and Ministério da Ciência, Tecnologia e Ensino Superior. This work received financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT) through project UID/QUI/50006/2013. ; info:eu-repo/semantics/publishedVersion
