SAMPLING AND SENSING STRATEGIES FOR NOVEL APPLICATIONS WITH AN ARTIFICIAL OLFACTORY SYSTEM

L’utilizzo dei cinque sensi, di cui ognuno di noi è normalmente dotato, ci permette quotidianamente di percepire ed interpretare il mondo che ci circonda, molto spesso senza aver coscienza di farne uso, ma semplicemente sfruttando i risultati che ne otteniamo per l’interazione con l’ambiente circostante. L’olfatto è probabilmente uno dei sensi del quale l’essere umano, nella sua evoluzione, ha perso maggiormente la capacità di sfruttare al massimo le potenzialità. Tuttavia l’odore rappresenta una importante sorgente di informazioni, grazie alla capacità di sintesi di una serie di parametri e di interazioni che noi non siamo in grado di raccogliere, interpretare ed elaborare contemporaneamente. L’oggetto di questa tesi è il naso elettronico realizzato presso i laboratori del Gruppo Sensori e Microsistemi dell’Università degli Studi di Roma ‘Tor Vergata’. L’obiettivo del lavoro è quello di individuare le problematiche fondamentali relative all’utilizzo di questa tecnologia e, tramite lo studio delle possibili soluzioni, raggiungere un generale perfezionamento dell’intero sistema. Sono svariati i campi nei quali le grandi potenzialità di un sistema olfattivo artificiale possono trovare utile applicazione. La caratteristica multidisciplinare di un così differenziato ventaglio di applicazioni, richiede la progettazione di una serie di sistemi di campionamento specifici per ogni scopo. Sebbene il cuore dell’intero sistema consista nei suoi principi di funzionamento e nel tipo di materiale sensibile utilizzato, il campionamento riveste una importanza fondamentale all’interno della catena di misura, perché attraverso la sua ottimizzazione si rende possibile un efficace utilizzo dello strumento nella pratica dei problemi reali relativi ai diversi campi. Proprio per questa ragione, il modo migliore di operare è quello di progettare dei protocolli sperimentali ‘ad hoc’ specifici per ogni applicazione. In questa tesi sono considerate tre differenti sperimentazioni: applicazioni in campo medico ed ambientale, e campionamento dell’odore in condizioni statiche. In particolare viene presentata l’esperienza di sei anni di sperimentazioni relative allo studio del tumore al polmone tramite l’analisi dell’espirato per mezzo del naso elettronico.Everyday, everyone of us uses the five senses, very often without consciousness at all of using them, but simply exploiting the results. The results consist in an interpretation of the real world around us. Olfaction is probably one of the senses humans have lost potentiality to exploit during evolution, but odour is a very important source of data, because of the power of synthesis of a lot of interactions and parameters we are not able to collect, read and elaborate at the same time. An existing technology, the Electronic Nose of the Sensors and Microsystems Group of the University of Rome ‘Tor Vergata’, is the objective of this Thesis. The aim is to ask fundamental questions about it, and by studying the possible solutions, reach the whole system improvement. The great potentialities of artificial olfactory systems can be exploited in many fields. This multidisciplinary range of applications asks for designing of dedicated sampling systems depending on the different scope. Although the working principle and the sensitive material are the basis on which these devices are developed, the sampling, within the measure chain, is a fundamental step to optimize the whole system performances. According to these considerations the best way for designing “ad hoc“ experimental set is to specialize a specific sampling procedure for each application. In this thesis three different studies are considered: medical and environmental applications, and odour sampling in static conditions. In particular, the experience of the six years of experiments dedicated to lung cancer study by mean of e-nose breath analysis is illustrated

Smart Device for the Determination of Heart Rate Variability in Real Time

This work presents a first approach to the design, development, and implementation of a smart device for the real-time measurement and detection of alterations in heart rate variability (HRV). The smart device follows a modular design scheme, which consists of an electrocardiogram (ECG) signal acquisition module, a processing module and a wireless communications module. From five-minute ECG signals, the processing module algorithms perform a spectral estimation of the HRV. The experimental results demonstrate the viability of the smart device and the proposed processing algorithms.Fundación Pública Andaluza Progreso y Salud. Gobierno de Andalucía PI-0010-2013 y PI-0041-2014Ministerio de Economía y Competitividad (Instituto de Salud Carlos III) PI15 / 00306 y DTS15 / 00195CIBER-BBN INT-2-CAR

A Novel Approach for Prostate Cancer Diagnosis using a Gas Sensor Array

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Biosensors for Detection and Monitoring of Joint Infections

The aim of this review is to assess the use of biosensors in the diagnosis and monitoring of joint infection (JI). JI is worldwide considered a significant cause of morbidity and mortality in developed countries. Due to the progressive ageing of the global population, the request for joint replacement increases, with a significant rise in the risk of periprosthetic joint infection (PJI). Nowadays, the diagnosis of JI is based on clinical and radiological findings. Nuclear imaging studies are an option but are not cost-effective. Serum inflammatory markers and the analysis of the aspirated synovial fluid are required to confirm the diagnosis. However, a quick and accurate diagnosis of JI may remain elusive as no rapid and highly accurate diagnostic method was validated. A comprehensive search on Medline, EMBASE, Scopus, CINAH, CENTRAL, Google Scholar, and Web of Science was conducted from the inception to June 2021. The PRISMA guidelines were used to improve the reporting of the review. The MINORS was used for quality assessment. From a total of 155 studies identified, only four articles were eligible for this study. The main advantages of biosensors reported were accuracy and capability to detect bacteria also in negative culture cases. Otherwise, due to the few studies and the low level of evidence of the papers included, it was impossible to find significant results. Therefore, further high-quality studies are required

FIRB "SQUARE" project: nano-structured sensors for the detection of the polluting in engine exhaust gases and for indoor air quality monitoring

The present work is a final dissemination of activities carried out and main results obtained in the national founded project Firb "Square". The project is leaded by Centro Ricerche Fiat and it involves the most qualified national public Research Institutes and Universities active in the fields of nanomaterials synthesis, nanotechnology and gas sensors development

Methodological considerations for large-scale breath analysis studies : lessons from the U-BIOPRED severe asthma project

Methods for breath sampling and analysis require robust quality assessment to minimise the risk of false discoveries. Planning large-scale multi-site breath metabolite profiling studies also requires careful consideration of systematic and random variation as a result of sampling and analysis techniques. In this study we use breath sample data from the recent U-BIOPRED cohort to evaluate and discuss some important methodological considerations such as batch variation and correction, variation between sites, storage and transportation, as well as inter-instrument analytical differences. Based on this we provide a summary of recommended best practices for new large scale multi-site studies

Breathomics can discriminate between anti IgE-treated and non-treated severe asthma adults

Rationale: Omalizumab, an anti-IgE monoclonal antibody, is indicated in adults with severe persistent allergic asthma. Exhaled molecular markers can provide phenotypic information in asthma. Objectives: Determine whether adults with severe asthma on omalizumab (anti-IgE+) have a different breathprint compared with those who were not on anti-IgE therapy (anti-IgE-) as assessed by eNoses and gas chromatography/mass spectrometry (GC/MS) (breathomics). Methods: This was a cross-sectional analysis of the U- BIOPRED adult cohort. Severe asthma was defined by IMI-criteria [Bel, Thorax 2011]. Anti-IgE+ patients were on a regular treatment with s.c. omalizumab (150-375 mg) every 2-4 weeks. Exhaled volatile compounds trapped on adsorption tubes were analysed by a centralized eNose platform (Owlstone Lonestar, two Cyranose 320, Comon Invent, Tor Vergata TEN), including a total of 190 sensors, and GC/MS. Recursive feature elimination (http://topepo.github.io/caret/rfe.html) was used for feature selection and random forests, more robust to overfitting, for classification. Results: 9 anti- IgE+ (females/males 2/7, age 52.6±16.3 years, mean±SD, 1/2/6 current/ex/nonsmokers, pre-bronchodilator FEV1 70.6±21.1% predicted value) and 30 anti-IgE- patients (18/12 females/males, age 53.2±14.2 years, 0/16/14 current/ex/nonsmokers, pre-bronchodilator FEV1 59.6±30.7% predicted value) were studied. Conclusions: Preliminary results suggest that breathomics can distinguish between anti-IgE+ and anti-IgE- severe asthma patients

SAMPLING AND SENSING STRATEGIES FOR NOVEL APPLICATIONS WITH AN ARTIFICIAL OLFACTORY SYSTEM

L’utilizzo dei cinque sensi, di cui ognuno di noi è normalmente dotato, ci permette quotidianamente di percepire ed interpretare il mondo che ci circonda, molto spesso senza aver coscienza di farne uso, ma semplicemente sfruttando i risultati che ne otteniamo per l’interazione con l’ambiente circostante. L’olfatto è probabilmente uno dei sensi del quale l’essere umano, nella sua evoluzione, ha perso maggiormente la capacità di sfruttare al massimo le potenzialità. Tuttavia l’odore rappresenta una importante sorgente di informazioni, grazie alla capacità di sintesi di una serie di parametri e di interazioni che noi non siamo in grado di raccogliere, interpretare ed elaborare contemporaneamente. L’oggetto di questa tesi è il naso elettronico realizzato presso i laboratori del Gruppo Sensori e Microsistemi dell’Università degli Studi di Roma ‘Tor Vergata’. L’obiettivo del lavoro è quello di individuare le problematiche fondamentali relative all’utilizzo di questa tecnologia e, tramite lo studio delle possibili soluzioni, raggiungere un generale perfezionamento dell’intero sistema. Sono svariati i campi nei quali le grandi potenzialità di un sistema olfattivo artificiale possono trovare utile applicazione. La caratteristica multidisciplinare di un così differenziato ventaglio di applicazioni, richiede la progettazione di una serie di sistemi di campionamento specifici per ogni scopo. Sebbene il cuore dell’intero sistema consista nei suoi principi di funzionamento e nel tipo di materiale sensibile utilizzato, il campionamento riveste una importanza fondamentale all’interno della catena di misura, perché attraverso la sua ottimizzazione si rende possibile un efficace utilizzo dello strumento nella pratica dei problemi reali relativi ai diversi campi. Proprio per questa ragione, il modo migliore di operare è quello di progettare dei protocolli sperimentali ‘ad hoc’ specifici per ogni applicazione. In questa tesi sono considerate tre differenti sperimentazioni: applicazioni in campo medico ed ambientale, e campionamento dell’odore in condizioni statiche. In particolare viene presentata l’esperienza di sei anni di sperimentazioni relative allo studio del tumore al polmone tramite l’analisi dell’espirato per mezzo del naso elettronico.Everyday, everyone of us uses the five senses, very often without consciousness at all of using them, but simply exploiting the results. The results consist in an interpretation of the real world around us. Olfaction is probably one of the senses humans have lost potentiality to exploit during evolution, but odour is a very important source of data, because of the power of synthesis of a lot of interactions and parameters we are not able to collect, read and elaborate at the same time. An existing technology, the Electronic Nose of the Sensors and Microsystems Group of the University of Rome ‘Tor Vergata’, is the objective of this Thesis. The aim is to ask fundamental questions about it, and by studying the possible solutions, reach the whole system improvement. The great potentialities of artificial olfactory systems can be exploited in many fields. This multidisciplinary range of applications asks for designing of dedicated sampling systems depending on the different scope. Although the working principle and the sensitive material are the basis on which these devices are developed, the sampling, within the measure chain, is a fundamental step to optimize the whole system performances. According to these considerations the best way for designing “ad hoc“ experimental set is to specialize a specific sampling procedure for each application. In this thesis three different studies are considered: medical and environmental applications, and odour sampling in static conditions. In particular, the experience of the six years of experiments dedicated to lung cancer study by mean of e-nose breath analysis is illustrated

Electronic Nose Technology in Respiratory Diseases

Electronic noses (e-noses) are based on arrays of different sensor types that respond to specific features of an odorant molecule, mostly volatile organic compounds (VOCs). Differently from gas chromatography and mass spectrometry, e-noses can distinguish VOCs spectrum by pattern recognition. E-nose technology has successfully been used in commercial applications, including military, environmental, and food industry. Human-exhaled breath contains a mixture of over 3000 VOCs, which offers the postulate that e-nose technology can have medical applications. Based on the above hypothesis, an increasing number of studies have shown that breath profiling by e-nose could play a role in the diagnosis and/or screening of various respiratory and systemic diseases. The aim of the present study was to review the principal literature on the application of e-nose technology in respiratory diseases

Design and Test of a Biosensor-Based Multisensorial System: A Proof of Concept Study

Sensors are often organized in multidimensional systems or networks for particular applications. This is facilitated by the large improvements in the miniaturization process, power consumption reduction and data analysis techniques nowadays possible. Such sensors are frequently organized in multidimensional arrays oriented to the realization of artificial sensorial systems mimicking the mechanisms of human senses. Instruments that make use of these sensors are frequently employed in the fields of medicine and food science. Among them, the so-called electronic nose and tongue are becoming more and more popular. In this paper an innovative multisensorial system based on sensing materials of biological origin is illustrated. Anthocyanins are exploited here as chemical interactive materials for both quartz microbalance (QMB) transducers used as gas sensors and for electrodes used as liquid electrochemical sensors. The optical properties of anthocyanins are well established and widely used, but they have never been exploited as sensing materials for both gas and liquid sensors in non-optical applications. By using the same set of selected anthocyanins an integrated system has been realized, which includes a gas sensor array based on QMB and a sensor array for liquids made up of suitable Ion Sensitive Electrodes (ISEs). The arrays are also monitored from an optical point of view. This embedded system, is intended to mimic the working principles of the nose, tongue and eyes. We call this setup BIONOTE (for BIOsensor-based multisensorial system for mimicking NOse, Tongue and Eyes). The complete design, fabrication and calibration processes of the BIONOTE system are described herein, and a number of preliminary results are discussed. These results are relative to: (a) the characterization of the optical properties of the tested materials; (b) the performance of the whole system as gas sensor array with respect to ethanol, hexane and isopropyl alcohol detection (concentration range 0.1-7 ppm) and as a liquid sensor array (concentration range 73-98 μM). © 2013 by the authors; licensee MDPI, Basel, Switzerland