Daniel Armada- Development of miniaturized air sampling methods for the monitorization and analysis of different pollutants in indoor and
outdoor environments (WG4)
Host: Dr Nuno Ratola, LEPABE, University of Porto, Portugal
Figure 1: Evaporation of extracts from air samples for concentration prior to GC-MS analysis.
During the Short-Term Scientific Mission (STSM) supported by the COST Action CA 16215 I have been able to learn about several sustainable sample preparation techniques for the analysis of air pollutants, as well as to deepen my knowledge of passive air sampling. The families of pollutants studied were polycyclic aromatic hydrocarbons, synthetic musks and siloxanes. For this purpose, air samples collected by passive sampling using a polymer resin were analysed by gas chromatography coupled to mass spectrometry (GC-MS) after the extraction of the target compounds with a sustainable methodology employing low energy. In addition, I was able to spend a few days preparing samples of wastewater from the sewage treatment plant for the monitoring of siloxanes in them.
This scientific exchange experience has been very positive and has given me a lot of new knowledge. It was very fruitful for me to have been able to work with Dr. Nuno Ratola, as well as with his entire team. I hope that this stay will help both research groups to collaborate in future scientific projects
Prof Nikola Sakač - Estradiol detection in water by Quartz-Crystal Microbalance (QCM) and optical based biosensors (Phase 3)
Host: Prof Raffaele Velotta, Università di Napoli Federico II, Italy [16th of February - 3rd of March 2020]
Discussion of magnetic nanoparticles
Results obtained by DLS measurement
CQM measuring setup
The work carried out during STSM Phase 3 was divided in two parts: a)Preparation of the new developed estradiol sensors: Assembling and testing the measuring equipment for QCM sensing/Synthesize the magnetic nanoparticles for pre-concetration protocol; and b) pre-concentration protocol and measurement campaign on real samples.
There were two main results of the STSM research: a) We finished and tested the QCM based estradiol biosensor; and b) We synthesized and characterized magnetic core-shell nanoparticles and successfully employed them for pre-concentration All the results were directly connected to the main aims of the WG5 of the Action. The data obtained by the QCM determination will be presented in the incoming paper obtained by the new proposed STSM. The STSM was very intensive also in networking and discussion about project applications.
Dr Claudio Larosa - Dynamic light scattering: an easy portable device for spherical nanoparticles detection
Host: Prof Dr Mile Ivanda, Ruđer Bošković Institute of Zagreb, Croatia [29th of November - 12th of December 2020]
The Ruđer Bošković Institute of Zagreb, Croatia located in a vaster green park and the main board used for our test connected to the photodiode.
The STSM of Dr. Claudio Larosa was performed at the Ruđer Bošković Institute of Zagreb, Croatia under the guide of the Head of laboratory Dr. Mile Ivanda and his colleague Dr. Lara Mikac. The laboratory unit in the last decade have added competence on synthesis and nano-fabrication concerning the silica particles with several highlight output; one of them is the implication in small batteries of new generation within Ph.D. program and master thesis. internationalization of the claimant.
The purpose of this mission was to realize a smart device employing two main board USB cards, arranged them in comparison and then define the best high-quality of new device. On the other hand, device have the following characteristics: it is a 5 V power dispositive, low cost, stable over time with resistor protections into main circuit board and configured as minor electronic compounds with an automatic set control loop. Two approach were followed, first of all was utilized an Open-smart Rich UNO R3 Atmega328P card made in china compatible with Arduino software equipped with a multi expanded-card, while the second analogic card use a diverse approach more simplified but also more effective: The Theremino main board, made in Italy work without an amplified system on the sensor track. The first difference is based on the extensions card able to receive filtered signals with high signal / noise ratio and a gain from sensors and actuators. As first results we deduced that Theremino card programmed with Python language have more facilities respect to the Arduino approach. Thought Arduino offer updated software with some pre writing codes of easy availability, Theremino approach with its master card connected to Acd24 card offers greater signal gain without saturation of the input.
Dr Lorena Franco Martínez - Clinical validation of lateral flow assays for the detection of inflammation in canine samples
Host: Prof Dr Roman Dąbrowski, the University of Life Sciences in Lublin, Poland [1st June – 31st July 2021]
The STSM of Dr. Lorena Franco Martínez took place in the Veterinary Clinical Hospital of the Faculty of Veterinary Medicine, University of Life Sciences in Lublin under the supervision of Professor Dr. Roman Dąbrowski.
The main aim of this STSM is to analytically and clinically validate a prototype of a new lateral flow immunoassay (LFIA) developed for the detection of C-reactive protein (CRP) in dogs. During the stay, the lateral flow immunoassay was evaluated using surplus serum samples from dogs attending the veterinary hospital. The obtained data was recorded and will serve for the assay optimization and improvement.
The STSM was also very fruitful in terms of collaboration and changes of knowledge between the applicant and the host group. While the host group received a brief description about LFIA use and development, the applicant was able to evaluate her assay in real time and was aware about the clinicians needs in terms of test diagnosis.
Dr René Herrera - Characterization of chemical components used for biobased treatments of wood with portable NIR sensors
Host: Université de Pau et des Pays de l'Adour (UPPA), IPREM, IUT des Pays de l’Adour, Mont de Marsan, France [17th of June - 4th of July 2021]
The main objective of the STSM was to study formulations for wood treatments based on natural products and their effect on specific properties. My research focused on the study and preparation of natural resins and additives, along with the use of NIR for the quality control of targeted properties. During the STSM different products were prepared and some physical-chemical properties were measured. Moreover, a set of products for spectral measurements with portable NIR devices was prepared.
The goal of this collaborative research is to assess whether portable NIR techniques are suitable for the identification, evaluation, and prediction of the quality/performance of biobased products. This STSM allowed me to prepare different products in the laboratory and start the development of a robust database that combines the results of selected physical-chemical parameters. After completing the data analysis, a scientific publication is planned in collaboration with researchers from the Xylomat group (IPREM, host institution).
Dr Milos Dvorak – Miniaturised-μSPE-3D printed devices coupled to μ-EME for automatic sample Pretreatment
Host: University of the Balearic Islands, Palma de Mallorca, Illes Balears, Palma de Mallorca, Spain [3th of July - 13th of August 2021]
The sketch of the novel 3D-printed microextraction system is presented on the Fig. 1.
The sketch presents an efficient platform for µ-electro membrane extraction (µ-EME) and it is based on 3D printed technology. The design allows an easy, but the robust connection with the sequential injection system for fully automated handling of operational solutions and two inputs for electrodes.
The resulted chromatogram of the analysed acceptor phase after µ-EME is presented in fig. 2, where various acidic drugs have been extracted.
This system was successfully tested as a first stage of the idea to incorporate monolithic sorbent in predestinated part of this platform. This idea is currently being tested in the framework of the cooperation of working groups established thanks to the COST programme.
Dr Stavroula Golfomitsou - Analysis of silver tarnish using Linear Sweep Voltammetry
Host: Christian Degrigny, Haute École Arc Conservation-restoration (HE-Arc CR), Neuchâtel, Switzerland [6th - 12th of June 2021]
The STSM took place in the scientific laboratories of Haute Ecole Arc(HE-Arc CR) and its conservation-restoration department hosted by Prof Christian Degrigny. The aim was to explore MiCorr as an educational and research tool to create digital models of corrosion stratigraphies observed on metals. I documented two objects creating digital stratigraphies of the corrosion structures observed macroscopically and under binocular microscope. The two objects documented and drawn were an aluminium alloy fork and a copper alloy bracelet which was sampled earlier and photos of the section under a binocular and SEM were available and used to complement my observations. The objects were analysed using XRF. The stratigraphies once imported into MiCorr were compared with those available in the database.
The fork was also analysed as part of training to use DiscoveryMat, an application based on the measurement of the corrosion potential (Ecorr) of a metal versus time. . The measurements are taken three times in three solutions and are compared to those of known alloys stored in a database allowing the identification of the alloy analysed. Finally, I was trained in the use of the Pleco, an electrolytic pen used in the conservation of silver objects.
All tools are low cost, easy to use and make use of open access software. Digital tools are of extreme importance and sharing of such resources are valuable for all researchers in conservation.
Dr Nicola Ricotta - Analysis of silver tarnish using Linear Sweep Voltammetry
Host: Christian Degrigny, Haute École Arc Conservation-restoration (HE-Arc CR), Neuchâtel, Switzerland [6th - 12th of June 2021]
Open Circuit Potential (OCP) and Linear Sweep Voltammetry (LSV) measurement phases in progress. Left: Christian Degrigny. Right: Nicola Ricotta.
Silver tarnish causes the modification of the surface appearance of silver artefacts. To remove it, electrolytic cleaning is often used. The parameters for electrolytic cleaning are derived from those for silver tarnish analysis obtained with Linear Sweep Voltammetry (LSV). LSV is a very sensitive surface analysis technique. Our work aims to apply LSV with an electrolytic pencil called Pleco to locally identify silver tarnish on artefacts. Eventually, the defined parameters will be used for the controlled electrolytic cleaning of their metal surface. Although the Pleco was developed by the Haute École Arc Conservation-restoration (HE-Arc CR) in Neuchâtel, the host institute of this STSM, the robustness of the electrochemical device (relevance of the data collected, reproducibility of results) has not been the subject of much work. Thus, the behavior of the reference electrode used, namely a glassy carbon rod, which is normally employed as an auxiliary electrode, is not perfectly controlled. Furthermore, the LSV plots obtained show fluctuations which are due to the circulation of the electrolyte (it is constantly renewed) within the Pleco and which must be limited to a minimum in order to correctly visualize the cathodic peaks produced during the reduction of the silver tarnish. To achieve this, the work carried out was structured in three main steps: - Production of artificial silver tarnish on sterling silver coupons that best matches the tarnish encountered on real artefacts (heterogeneous in colour and then thickness); - Control of the electrochemical behavior of the glassy carbon (GC) rod; - Adjustment of the Pleco electrolyte flow to produce relevant and reproducible LSV plots useful for correctly analyzing the silver tarnish formed on the coupons. The work carried out during this STSM has allowed us to deepen our knowledge on how to better use the Pleco electrolytic pencil in order to obtain LSV plots without too many fluctuations.
Ms Angeliki Pateraki - Vac-HSSPME sampling of volatiles emitted by tomato fruits and relation to organics present in the fruit
Host: Department of Drug Science and Technology at the University of Turin, Italy [1st of June – 2nd of July 2021]
Figure 1. A. Scheme of the extraction procedure from Solanum lycopersicum sample. Proposed Vac-HSSPME method. B. B1. Spatial distribution of the experimental points in the Doehlert design, during the optimization of the Vac-HSSPME method. B2. Estimated response surface for peak areas sum of a) aldehyde b) alcohol c) ketone and d) acid compounds, considering extraction time and temperature factors. Response surfaces were calculated for both Vac-HSSPME and HSSPME method. C. Chromatograms from the volatile fingerprint of piccadilly tomato by adopting the Vac-HSSPME and Reg-HSSPME method. Sampling conditions: 30 min of extraction time and 50°C of extraction temperature. D. Extraction efficiencies of target analytes emitted from piccadilly cherry tomato puree, obtained with (i) HSSPME and (ii) Vac-HSSPME at 50oC and 30min sampling.
The development of a vacuum assisted headspace solid phase microextraction (Vac-HSSPME) procedure for the ex vivo monitoring of the volatile fraction emitted by tomato, was carried out by visiting the Department of Drug Science and Technology at the University of Turin (Italy) under the supervision of Professor Cecilia Cagliero from June 1st to July 2nd. The optimization of the technique was performed by applying an experimental design, while the performance of the Vac-HSSPME sampling was compared to that of sampling under regular conditions. As optimal conditions were considered the following: 2 gr of frozen puree, 1gr of NaCl, 30 sec airevacuation, 30 min sampling time and 50°C sampling temperature. By using this optimized method, 55 volatiles were detected in piccadilly tomato fruit samples. These compounds included aldehydes, alcohols, ketones, acids, oxygen‐containing heterocyclic compounds as well as sulfur- and nitrogen- containing heterocyclic compounds. In addition, it was proved that the application of the air-evacuation enhanced the number and the quantity of the most extracted volatiles. Vacuum showed slightly better performance on lower volatility compounds. Thus, sampling under vacuum is a new and powerful approach for the volatile
analysis in food samples.
Prof Nikola Sakač - New potentiometric sensor for anionic surfactants – Phase 1
Host: Prof Rafaelle Velotta, Dipartamento di Fisica Ettore Pancini, Università di Napoli Federico II, Italy [3rd –26th of July 2021]
Upper left to right: Synthesized molecules of cationic surfactants; Selected cationic surfactant; Sensing membrane fabrication.
Lower left to right: Fabricated sensors; Research group.
Tensides or surfactants are surface active agents. They decrease the tension of water surface. They are used for washing, cleaning and disinfection in broad spectra of industries and everyday home products. Rapid industrialization, the population growth and increased standard of living caused the constant growth of surfactants demands. Anionic surfactants take the biggest part of the global production (about 70%) with the estimated CAGR of 4.2 % for the forecast period of 2020 to 2027. (MarketsandMarkets, 2020) Anionic surfactants have a negative impact on the environment and there is a need to establish fast, low cost and sensitive devices and sensors to monitor anionic surfactants not just in environment but also in quality control.
The development of the new low-cost potentiometric sensor for surfactants is planned in two phases. This first phase was done by Prof. Sakač with the group of Prof. Velotta in Italy. We synthesized a new cationic surfactant molecules, characterized them by LC-MS, NMR, IR and elemental analysis, then we synthesized the ion-pair, which is the sensing element in the sensor membrane. Next, the sensing membrane was used to fabricate the surfactant sensor prototype. The sensors were characterized on response, LOD, dynamic response, interferences, stability, drift, pH influence, etc. Prototype showed promising properties and potential use in a broad range of concentrations from 10-7 M to 10-3M During the STSM we made intensive discussions about potential project applications on the topic. Next step in development was a phase two.
Prof Elefteria Psillakis – Vac-HSSPME followed by GCxGC for the analysis of perishable food and food samples
Host: Department of Drug Science and Technology at the University of Turin, Italy [5th - 15th of July 2021]
The aim of this work was to develop a methodology based on vacuum headspace solid-phase microextraction (HS-SPME) and vacuum headspace SPME Arrow (representing low and high capacity sorbents repsectively) at low sampling temperatures coupled with GC×GC-MS to obtain a qualitative characterization of the total volatile components of milk. Initially the experimental parameters affecting extraction were optimized under regular pressure conditions (1 atm). The optimum conditions found were tested under vacuum using both SPME and SPME Arrow and results were compared to those at 1 atm. Samples from one raw milk sample were also tested. GCxGC allowed the separation and identification of a large number of volatiles present in the milk. From these close to 100 markers were selected and their variation in volume was monitored during optimization of the methods and analysis of real samples. At all cases, methods working under vacuum yielded higher volumes and a larger number of analytes could be detected. In particular, the result with the vacuum approach at 4 °C yielded extraction efficiencies that were similar to those obtained with the regular methodology at 40 °C. The proposed method eliminates the need for heating the sample, thus avoiding sample deterioration or creation of artefacts. The approach also opens the door t. anew era of analyses of perishable food.