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Funding Information: This work was supported by the NoAW project (‘‘Innovative approaches to turn agricultural waste into ecological and economic assets”), founded by the European Union Horizon 2020 research and innovation program under the grant agreement No 688338. This research was carried out within the Agritech National Research Center and received funding from the European Union Next-GenerationEU (PIANO NAZIONALE DI RIPRESA E RESILIENZA (PNRR)–MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4–D.D. 1032 17/06/2022, CN00000022), Italy. This study was also funded by national funding by FCT, Foundation for Science and Technology, MCTES, and by ESF (European Social Fund) through NORTE 2020 (Programa Operacional Região Norte), Portugal, through the individual PhD research grant (SFRH/BD/146080/2019) of V.L. This work was also supported by the MEtRICs unit which is funded by national funds from FCT/MCTES (UIDB/04077/2020 and UIDP/04077/2020) and by the Associate Laboratory for Green Chemistry–LAQV which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020). Publisher Copyright: © 2023 by the authors. In the last 20 years, an increased interest has been shown in the application of different types and combinations of enzymes to obtain phenolic extracts from grape pomace in order to maximize its valorization. Within this framework, the present study aims at improving the recovery of phenolic compounds from Merlot and Garganega pomace and at contributing to the scientific background of enzyme-assisted extraction. Five commercial cellulolytic enzymes were tested in different conditions. Phenolic compound extraction yields were analyzed via a Design of Experiments (DoE) methodology and a second extraction step with acetone was sequentially added. According to DoE, 2% w/w enzyme/substrate ratio was more effective than 1%, allowing a higher total phenol recovery, while the effect of incubation time (2 or 4 h) variation was more enzyme-dependent. Extracts were characterized via spectrophotometric and HPLC-DAD analyses. The results proved that enzymatic and acetone Merlot and Garganega pomace extracts were complex mixtures of compounds. The use of different cellulolytic enzymes led to different extract compositions, as demonstrated using PCA models. The enzyme effects were observed both in water enzymatic and in the subsequent acetone extracts, probably due to their specific grape cell wall degradation and leading to the recovery of different molecule arrays. publishersversion published

Uso del QPCS con matricole universitarie (PLS–Chimica Unibo) dall’a.a. 2018-19, con ipotesi di partenza: lo sviluppo dell’autodirezione nell’apprendimento favorisce la continuità negli studi. Il percorso è in tre fasi: a) somministrazione del QPCS a matricole chimiche (N=436); b) restituzione in presenza dei risultati; c) tutorato a 44 studenti. Riflessioni: modalità di restituzione, uso dei risultati QPCS, reazioni degli studenti. Obiettivo: costruire un quadro concettuale per futura ricerca., Dirigere se stessi nello studio e nel lavoro. Competenzestrategiche.it: strumenti e applicazioni

The present review proposes an exhaustive focus on what are the metals of interest, and what is the state of the art about analytical methodologies suitable to detect these toxic metals in herbal medicines. This review would also be a stimulus to solicit International Organizations to fill the gap of the lack of strict and comprehensive laws regulating the maximum allowable concentrations for an increasing number of contaminants in these matrices, especially considering their enormous consumption. Herbal medicines are more and more worldwide used. This fact certainly presents serious problems for the potential human health risks. This is due to the fact that the laws in force generally do not provide for strict quality controls of herbal medicines to certify the concentration of compounds and elements that may be hazardous for human health, and sometimes very severe or even lethal. Heavy metals have a decidedly substantial part of the contaminants in herbal medicines.

Summary/Riassunto The aim of this work is to clarify some aspects that should allow an interpretation of the analytical data unique, shared and accepted by the community as obtained through statisticalmathematical tools (chemometric) essential in the expression and interpretation of any measurements. There is objectively a difficulty of communication between scientists and jurists when applying regulations involving the use of statistical and mathematical tools: literature is filled by several lawsuits resulting from this difficulty; it being understood the right of defense that a party has, however, you need to put a fundamental point on certain aspects (numeric, and therefore objective) that should not be matter for discussion anymore. Regarding the breathalyzer, it is already accepted the conversion constant between the concentration of ethanol in exhaled air and blood concentration: for such constant, regardless of how it can be scientifically shareable its interpretation, during a judicial procedure no objection is admissible. But, about the verification of exceeding the legal limits, are still needed to establish an indisputable method, which must take into account all the law prescriptions: both the established limits, both the measurement uncertainties associated with the breathalyzer. This paper aims to highlight how, once the analytical result expressed in the correct form (significant digits, uncertainty, etc.), you can beyond any reasonable doubt compare the limit values to express an objective and unequivocal judgment of compliance to the norm. Lo scopo della presente riflessione è chiarire alcuni aspetti che dovrebbero permettere un'interpretazione del dato analitico unica, condivisa e da tutti accettata in quanto ottenuta attraverso strumenti statistico-matematici (chemiometrici) essenziali nell'espressione ed interpretazione di qualsiasi misurazione tecnica. Esiste obiettivamente una difficoltà di comunicazione tra Scienziati e Giuristi quando si applicano normative che comportano l’uso di strumenti statistici e matematici: numerose cause derivanti da tale difficoltà riempiono la letteratura giudiziaria; fermo restando il diritto di difesa che una controparte ha, è necessario però porre un punto fermo su certi aspetti (numerici, e quindi oggettivi) che non dovrebbero più essere motivo di discussione. Nel caso dell’etilometro, si è già posto un punto fermo nell’utilizzo della costante di conversione tra concentrazione di etanolo nell’aria espirata e concentrazione nel sangue: per tale costante, indipendentemente da quanto possa essere scientificamente condivisibile una sua interpretazione, in sede dibattimentale non viene più ammessa alcuna contestazione. Ma per quanto riguarda la verifica del superamento dei limiti di legge c’è ancora bisogno di stabilire un metodo incontestabile, che deve tenere conto di tutte le indicazioni della legge: sia i limiti stabiliti, sia le incertezze di misura associate alle misure effettuate su persone soggette a controlli mediante etilometro. Nel presente lavoro si vuole mettere in luce come, una volta espresso il risultato analitico nella forma corretta (cifre significative, incertezza, etc.), si può oltre ogni ragionevole dubbio confrontarlo con i valori-limite per esprimere un oggettivo ed inequivocabile giudizio di conformità o meno alla norma.

Recently, the problem relevant to the increasing presence in the environment of platinum group metals (PGMs) have been a topical subject of great interest, even if the scientific attention has been generally addressed to platinum(II), palladium(II) and rhodium(III), and in few cases to iridium(III), osmium(VIII) and ruthenium(III). This is because the PGMs concentration is significantly growing as a consequence of their increasing use in the production of industrial catalysts, anticancer drugs, jewels, and especially autocatalytic converters. In the case of the last tools, their continuous incorrect use “stop and go” with consequent deterioration implies a considerable release of these metals in the environment. Even if initially the metals used in autocatalytic converters were platinum, palladium and rhodium, in recent years such PGMs were gradually replaced in part, or alloyed with osmium, ruthenium and, especially, iridium. In particular, in the last decade, and always more frequently, iridium is employed as alloying (10-20 % w/w) with platinum, palladium and rhodium in the manufacture of autocatalytic converters in order to withstand high temperature and high wear. Finally, it is also important to highlight that iridium is one of the least abundant elements in the environment, and, probably for this reason, very few data are available. Thus, this work intends to propose voltammetric methods for the determination of ultra-trace iridium in environmental samples: airborne particulate matter, superficial waters, soils/sediments, vegetables, mussels, clams and algae. To better validate the proposed analytical procedures, a critical comparison with spectroscopic measurements — electro-thermal atomic absorption spectroscopy (ET–AAS) because of its well established and tested robustness — has been also carried out and discussed here, taking into account all the parameters of interest to set-up an analytical method, such as precision, trueness, limit of detection and quantification, selectivity and, especially, sensitivity.

The widespread use has made preservatives become a special monitored group in commercial cosmetics, especially in the leave-on products due to the prolonged exposure. Additionally, recently there has been an increase in the demand for preservative-free cosmetics related to undesired adverse effects on human health, in order to minimize the amount in personal care products or produce preservative-free-cosmetics and verify the contents to avoid health risk. Hence, the simultaneous separation and trace-level determination in personal care products are important for both merchandise reliability and quality assurance. However, is not possible to exclude that heavy metals can be accumulated in the body over time and repetitive metal-containing product application can lead to significant exposure levels. In the case of some metallic powders such as nickel (Ni), lead (Pb), and cadmium (Cd), they are unintentionally added to the cosmetics as impurities during manufacturing of an ingredient or product, and represent a minor source of exposure compared to other pathways such as water, food or air. For these reasons it is necessary a deep knowledge of real toxics (organic and inorganic) content into personal care products and cosmetics using reliable, high-throughput, sensitive and selective analytical assays. In this chapter, recently developed method for the extraction, separation, and quantitative determination of organic (phthalates and parabens) and inorganic toxic (heavy metals) in cosmetic products are reported.

Cosmetics are widely used even for daily usage. Raw materials and industrial machines used for their preparation are inevitably affected by contamination from metals, because these species are ubiquitous in the world. For instance, nickel, lead and cadmium are frequently unintentionally added to cosmetics as impurities during manufacturing. In fact, some metals are very dangerous for human health. This is true over safe limits of concentration even in the case of metals which are essential for human metabolism. Moreover, heavy metals may accumulate in the body over time and repetitive product applications, leading to significant exposure levels. International regulation about metals in cosmetics is very heterogeneous from Country to Country. Moreover, in many Countries the regulation is incomplete or absent. In some cases, regulations provide safe limits, but the analytical techniques useful to check for those limits are not indicated. In other cases, the safe limits are below the limit of detection of available analytical methodologies, hence the development of new methods is necessary. For these reasons, a deep knowledge of metals content in personal care products and cosmetics is necessary using reliable, and high-throughput, sensitive and selective analytical assays are needed. The present review proposes an exhaustive focus onwhat arethemetalsof interest, and what is the state of the art about analytical methodologies suitable to detectthesetoxic metals in cosmetics and personal care products (PCPs). This review would also be a stimulus to solicit International Organizations to fill the gap of the lack of strict and comprehensive laws regulating the maximum allowable concentrations for an increasing number of contaminants in these matrices, especially considering their enormous daily use.

Recently, pollution linked to airborne particulate matter has drawn attention. The issue is due to a drastic increase of anthropic activities: industrial activities, in all their different typologies, and more and more increasing vehicular traffic. As a consequence, the totality of the pollutants associated with the various types of particulate are everywhere strictly dependent on the type of source of the same particulate. Moreover, the particle size evidently has a particular importance, since the decrease of the aerodynamic diameter of particulate corresponds to greater ease of penetration of the same particulate in the deeper levels of the respiratory system. This obviously is a serious problem for human and animal health, implying high costs in health care. Due to multiple simultaneous sources in areas at high anthropic impact, there are many pollutants associated with airborne particulate matter, both of inorganic and organic kind, and even simultaneously present on the same particulate samples. In any case, the pollutant determination in airborne particulate matter certainly must be accurate, reproducible and it must be especially characterized by very low limits of detection. In particular, the present work reports and discusses the different analytical procedures for the voltammetric and spectroscopic determination of heavy metals and metalloids (copper, lead, cadmium, zinc, mercury, tellurium, arsenic, selenium, tin, antimony, vanadium, nickel, chromium) in airborne particulate matter sampled in two sites, differently influenced by anthropic pollution. An additional sampling, carried out in a zone at very low anthropic impact, was chosen for eventual comparisons. The chosen particulate-matter size was PM2.5 (aerodynamic diameter < 2.5 µm) even if the proposed methodologies evidently can be also applied to all other particle sizes of interest. A separate section will be dedicated to the analytical procedure for the determination in airborne particulate matter of new emerging anthropic polluting traffic-related pollutants, i.e. the platinum group metals (PGMs) — platinum, palladium, rhodium, osmium, ruthenium and iridium — that, in the last decade, have aroused much interest from scientific community.

L’orientamento negli studi è di fondamentale importanza per la felicità personale e collettiva: non trovare la propria strada negli studi e di conseguenza nel lavoro può causare insoddisfazione, e può impedire di dare il proprio meglio a sé stessi ed alla società di cui si fa parte. Risulta quindi determinante ogni azione che permetta ad un adolescente di comprendere quali siano i propri talenti, in modo da poterli spendere con la massima efficienza ed efficacia possibili. In questo lavoro vengono presentate le attività di orientamento svolte nell’ambito del Progetto/Piano Lauree Scientifiche dal 2005 al 2014. L’attività ha riguardato intere classi di scuole superiori, ed ha coinvolto 3732 alunni suddivisi in 204 classi di 40 scuole diverse, accompagnati da 112 insegnanti diversi; essa si proponeva un obiettivo di orientamento all’Università in generale ed alla Chimica in particolare. L’orientamento generale è stato perseguito mediante una lezione nella quale si spiegava agli alunni quale sia la missione degli Atenei, come sia strutturato l’Ateneo di Bologna e quali criteri si possano adottare per entrare consapevolmente nella complessa e ricca struttura accademica, diventando matricole motivate e di talento. L’orientamento alla Chimica è stato perseguito facendo entrare gli alunni dentro questa disciplina, vivendo in prima persona la giornata-tipo dello studente di Chimica dentro il Dipartimento di Chimica Ciamician: la lezione teorica in aula, l’esercitazione nel laboratorio chimico, l’elaborazione dei dati nel laboratorio informatico, la stesura di una relazione concisa ma esauriente; sono i vari aspetti del lavoro dello scienziato: studiare, sperimentare, elaborare e comunicare. Il tutto rigorosamente scientifico - anche se semplificato per poter essere compreso da alunni di scuola superiore - ma soprattutto divertente! Il tema della Chimica Forense nell’ambito delle “Indagini di Polizia Scientifica” è accattivante, quindi cattura l’attenzione e permette di superare l’iniziale smarrimento che può essere generato dalla rigorosa oggettività della scienza e dall’astrazione dei metodi matematici e statistici che essa usa.

The work regards the voltammetric determination of trace metals in different kinds of food matrices. First goal is relevant to the correct analytical procedure for the voltammetric determination of trace and ultra-trace metals - Platinum Group Metals (PGMs), Mercury (II), Copper (II), Lead (II), Cadmium (II) and Zinc (II) - in meals, vegetables, mussels, clams and fishes: this allows, evidently, to check high quality foodstuffs. The second goal is to show the advantages that the electrochemical approach may offer over atomic absorption spectroscopy. First, voltammetry, together with the standard addition method, is a valid analytical technique (good selectivity and, especially sensitivity) for the simultaneous element determination in complex matrices and it does not require enrichment steps, like solvent extraction, and/or particular sample treatments. Second, as regards precision, accuracy and limits of detection, the results obtained with the two techniques are both good and comparable in all cases, although voltammetry is better than atomic absorption spectroscopy, allowing simultaneous metal determinations in most cases. In fact, also Inductively Coupled Plasma (ICP) and Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) permit multi-element determination, but the great advantage in using voltammetry is certainly the equipment-related costs: very low in the case of voltammetry, extremely high in the case of ICP and ICP-MS, in the latter case as much as 25-30 times higher. In this work Electrothermal Atomic Absorption Spectroscopy (ETAAS) was also chosen as comparison technique because of its well-established and tested robustness.

The problem related to the presence of Platinum Group Metals (PGMs) in the environment has raised much attention and great interest in the scientific community. This is due to the fact that the PGMs are widely used in various fields, such as anticancer drugs, jewels production, photographic operations, industrial catalysts, and especially autocatalytic converters. In the last case, their continuous use and deterioration implies a considerable release of these metals in the environment. It should be noted that the metals initially used in autocatalytic converters were platinum, palladium and rhodium, but in recent years such PGMs were gradually and partially replaced, or alloyed with osmium and especially ruthenium. Their addition in the manufacture of autocatalytic converters helps them withstand high temperatures and wear, thus increasing the product life. Thus, the increasing use of autocatalytic converters shows two decidedly conflictual effects on the environment: an evident and drastic reduction of the concentration levels of lead, and, at the same time, an equally evident and widespread increase of the PGMs concentration, and in particular of ruthenium, due to its increasing use in recent years. This work proposes a voltammetric method for the determination of ultra-trace ruthenium in environmental samples: airborne particulate matter, vegetables, superficial waters, mussels, clams and soils/sediments. To better validate the proposed analytical procedure, a critical comparison with spectroscopic measurements - electrothermal atomic absorption spectroscopy (ET- AAS) because of its well established and tested robustness - has been also carried out and discussed here. All the parameters of interest for the set-up of an analytical method, such as trueness and precision (accuracy), limit of detection and quantification, selectivity and, especially, sensitivity were taken into account.

The paper proposes an analytical procedure regarding the voltammetric determination of chromium(VI), copper(II), lead(II), cadmium(II), zinc(II) and mercury(II) by differential pulse catalytic voltammetry (DPCV) in matrices involved in the food chain, but also employed as possible biological monitors for trace metal. The digestion of each matrix was carried out using a concentrated HCl-HNO3-H2SO4 acidic attack mixture. 0.23 mol L-1 dibasic ammonium tartrate buffer pH 4.9 + 5.9x10-2 mol L-1 NaBrO3 was employed as the supporting electrolyte. The voltammetric measurements were carried out using, as working electrodes, a stationary hanging mercury drop electrode (HMDE) [simultaneous determination of Cr(VI), Cu(II), Pb(II), Cd(II) and Zn(II)] and a gold electrode (GE) [determination of Hg(II)], a platinum electrode and Ag⎪AgCl⎪KClsat electrode as auxiliary and reference electrodes, respectively. The analytical procedure has been verified on the standard reference materials Mussel Tissue BCR-CRM 278 and Cod Muscle BCRCRM 422. For all the elements in the certified matrices, the precision as repeatability, expressed as relative standard deviation (sr) was lower than 6 %, while the trueness, expressed as relative error (e) was of the order of 5-6 %. Once set up on the standard reference materials, the analytical procedure was transferred and applied to fishes and molluscs sampled in the Po river mouth area.

In the environmental field and in the last decade, the scientific attention has been addressed to platinum group metals (PGMs) owing to their increasing concentration in all the environmental matrices. This is due to the increasing use of these metals in several fields as for example production of industrial catalysts, anticancer drugs, jewels, even if in any case the cause of their growing concentrations in the environment is consequence of the compelling employment of autocatalytic converters. In fact the incorrect use “stop and go” of these converters, with consequent deterioration and abrasion, certainly implies a considerable release in the environment of airborne particulate matter at high PGMs concentration, which results to be the greatest, if not the only, source of contamination of the various environmental matrices, i.e. superficial water, soils, sediments, vegetables and so on. Really, after the first massive use of platinum, palladium and rhodium in the production of autocatalytic converters, there has been a gradual reduction of these PGMs with consequent growing use of iridium, ruthenium and, especially, osmium. Indeed, in the last decade, and more and more frequently, osmium together with iridium has been employed as alloying with platinum, palladium and rhodium in the manufacturing of autocatalytic converters in order to withstand high temperature and high wear. In fact, osmium in particular is rarely used in its pure state, and it is instead considered an important alloying agent especially in high-wear applications, owing to its strong corrosion resistance even at very high temperatures. Thus, this work intends to propose voltammetric methods for the osmium determination at ultra-trace level concentration in environmental samples: airborne particulate matter, superficial waters, soils/sediments, vegetables, mussels, clams and algae. To better validate the proposed analytical procedures, a critical comparison with spectroscopic measurements — electro-thermal atomic absorption spectroscopy (ET–AAS) because of its well established and tested robustness — has been also carried out and discussed here, taking into account all the parameters of interest to set-up an analytical method, such as precision and trueness (that together give accuracy), limit of detection and quantification, selectivity and, especially, sensitivity.

A rapid diffusion of heavy metals as environmental contaminants has called the attention to their determination. Indeed, heavy metals, together with pesticides, are very dangerous pollutants owing to their bioaccumulation and toxicity. It is therefore necessary to determine these metals at trace and ultra-trace level especially in aquatic ecosystems to establish reasonable water quality criteria. Moreover, toxic metals accumulate in certain marine species and thus enter the aquatic food chain. In particular mussels and clams, but also oysters, shrimps, fish and algae, sequestrate and concentrate several metals from their aqueous environment, possibly becoming dangerous to human health in consequence of their consumption. In particular mussels, clams and oysters, being filtering organisms - an adult organism is able to filter also up to 4-5 L h-1, depending on its weight - they require particular attention and inspections before being sold on the market. In addition to this important and fundamental aspect of public health, the determination of heavy metals in mussels and clams, that are not only filtering organisms but also sessile species, can be usefully employed for bio-monitoring campaigns, that evaluate the long-term trend of the pollution load of an aquatic ecosystem, information that evidently cannot be provided by punctual determinations. For completely mapping environmental pollution, the sampling duration and cadence are very important. In our opinion, the use of bio-monitors (mussels and clams in the present case), just proposed by several authors, but certainly not scientifically supported, is possible only in the case of a long sampling plan. In any case, the metal determination in mussels and clams evidently must be accurate, reproducible and especially it must show very low limits of detection. The present work reports and discusses the different analytical methodologies for the voltammetric and spectroscopic determination of heavy metals (copper, lead, cadmium, zinc, mercury, arsenic, selenium, tin and antimony) in oysters, mussels and clams. A separate section will be dedicated to the analytical procedure for the determination in such organisms of new emerging anthropic polluting traffic-related pollutants, i.e., the platinum group metals (platinum, palladium, rhodium, osmium, ruthenium and iridium).

Yeasts are widely used in several areas of food industry, e.g. baking, beer brewing, and wine production. Interest in new analytical methods for quality control and characterization of yeast cells is thus increasing. The biophysical properties of yeast cells, among which cell size, are related to yeast cell capabilities to produce primary and secondary metabolites during the fermentation process. Biophysical properties of winemaking yeast strains can be screened by field-flow fractionation (FFF). In this work we present the use of flow FFF (FlFFF) with turbidimetric multi-wavelength detection for the number–size distribution analysis of different commercial winemaking yeast varieties. The use of a diode-array detector allows to apply to dispersed samples like yeast cells the recently developed method for number–size (or mass–size) analysis in flow-assisted separation techniques. Results for six commercial winemaking yeast strains are compared with data obtained by a standard method for cell sizing (Coulter counter). The method here proposed gives, at short analysis time, accurate information on the number of cells of a given size, and information on the total number of cells.

Naphthenic acids (NAs) are an important group of organic pollutants comprised predominantly of saturated aliphatic and alicyclic carboxylic acids. Although these compounds are toxic, recalcitrant, and persistent in oil sands deposits, we are just learning the diversity of microorganisms involved in NAs-degradation and the mechanisms by which NAs are biodegraded. Here, we described the ability of Rhodococcus sp. BCP1 and Rhodococcus opacus R7 to utilize two model naphthenic acids (NAs) i.e. cyclohexancarboxylic acid (CHCA) and cyclopentanecarboxylic acid (CPCA) as sole carbon and energy source. BCP1 strain degraded both the NAs with higher rates compared to R7; moreover, CHCA was shown to be metabolized faster than CPCA by both the Rhodococcus spp. Furthermore, genes coding for enzymes putatively involved in β-oxidation metabolism were identified in BCP1 genome. RT-PCR experiments showed that all these genes are induced by the growth of BCP1 on either CPCA or CHCA. These results suggest their involvement in β-oxidation metabolism of NAs by R. sp. BCP1.

Drug development is a time-consuming and costly process. Recently, the need of very sensitive and selective assays for the complete characterization of New Chemical Entities (NCE) has become very stringent. From Analytical Chemists, a partial answer to this problem was the development and validation of new methods that permit an improvement in terms of productivity (-high-throughput"), sensitivity and selectivity, especially using very recent hyphenated analytical assays, such as HPLC-MS/MS, GC-MS/MS or further complex couplings, that can provide more complete information in a single analysis. All data obtained by these novel techniques require a very deep and multifaceted analysis, in order to check the principal and fundamentals variables and to reject the others. In this scenario, chemometrics provide scientists with useful tools to interpret the large amounts of data generated by these complex analytical assays and allows for quality control, classification procedures, modelling studies. Discrimination between different molecules available as novel drugs and molecules having no interesting biological activities is easy by means of multivariate analysis. In this chapter we report recent advantages in analytical method hyphenation and chemometric approach applied to drug development.

1. MOTIVAZIONI E FINALITÀ Le finalità sono: 1) Introdurre gli alunni al metodo scientifico sperimentale, mediante la progettazione e l'esecuzione di semplici ma rigorose esperienze su metodiche basilari della chimica. 2) Informare gli alunni sulle scienze, facendogliele incontrare mediante esperimenti accattivanti sulle indagini forensi, con qualche "effetto speciale" che dia un tocco di aspetto ludico all'apprendimento. 3) Unire sperimentazione in prima persona e informazione sull'Università per guidare i ragazzi verso scelte consapevoli dopo il Diploma: continuare gli studi o no? Se sì, quale corso di Laurea scegliere? Con quali criteri? La motivazione sta nell’esperienza scientifica e didattica della responsabile dell’attività, che ha portato ad evidenziare come la piena consapevolezza di quali siano l’oggetto di indagine ed i metodi della chimica debba necessariamente passare attraverso lo svolgimento in prima persona di esperienze pratiche che siano in qualche modo ”divertenti”. Tale piena consapevolezza è necessaria affinché un diplomato effettui una scelta consapevole in merito al proprio percorso formativo post-diploma. 2. OBIETTIVI L’attività non ha l’obiettivo di insegnare agli alunni nozioni nuove. Lo scopo è partire dalle nozioni scientifiche apprese a scuola ed approfondirle con approccio meno scolastico e più accademico, ma sempre alla portata di un alunno non ancora diplomato, al fine di portarlo verso la consapevolezza di cosa sia l’oggetto di studio della chimica e di quale sia la sua importanza nel sapere universale. Su queste basi poggia l’obiettivo di orientamento: far capire ai ragazzi la natura di questa disciplina per dar loro strumenti per capire se essa sia tra i propri talenti naturali. Lo scopo finale è avere matricole di chimica che siano motivate e di talento. Riguardo all’effetto sugli insegnanti, essi hanno manifestato una significativa crescita professionale nell’interagire con docenti universitari. Spesso si tratta di insegnanti che non hanno una formazione universitaria in chimica: le attività qui proposte permettono loro di inquadrare meglio la disciplina e proporla ai loro alunni in modo più coinvolgente e interessante. 3. METODOLOGIA UTILIZZATA La progettazione avviene mediante incontri preliminari nei quali il docente unversitario valuta per ciascuna classe partecipante le conoscenze scientifiche già in possesso degli alunni, il programma didattico già da essi seguito ed i programmi didattici seguenti. Poiché ogni classe di alunni riceve una lezione frontale di 2 ore che è personalizzata sulla classe stessa, la progettazione serve a collocare l’attività PLS nel percorso scolastico degli alunni in modo armonioso e coerente. Inoltre si valuta quali tecniche analitiche siano meno note agli alunni in modo da mostrare loro qualcosa di nuovo rispetto alla scuola: l’esperienza di chimica quantitativa è opzionabile tra due (HPLC e AAS); quindi se per esempio se una classe ha già sperimentato l’AAS a scuola, allora la si farà esercitare su HPLC. Discorso dettagliato merita l’elaborazione statistica del dato analitico, la quale spesso è trattata marginalmente persino negli istituti tecnici: si approfondisce molto l’elaborazione dei dati e gli alunni vengono portati a svolgere lavoro individuale al calcolatore. Modalità di lavoro con gli studenti. Tutti gli alunni seguono una lezione introduttiva, nella quale vengono richiamati o spiegati i principi teorici alla base delle esperienze proposte e vengono date istruzioni su come svolgere il lavoro sperimentale. Dopo la lezione, i ragazzi vengono portati nel laboratorio chimico, dove svolgono esercitazioni lavorando in prima persona, a coppie, seguiti da insegnanti e tutori universitari. Al termine dell’esercitazione, i ragazzi passano in aula informatica, dove individualmente elaborano i dati da loro raccolti. Le esperienza proposte sono: 1) QUALITATIVA: ricerca di tracce di emoglobina mediante test al LUMINOLO; riconoscimento di droghe mediante TLC. 2) QUANTITATIVA: quantificazione di metalli nei residui dello sparo mediante AAS; analisi di eroina mediante HPLC. 4. ANALISI DEI RISULTATI E AUTOVALUTAZIONE Non è stata svolta verifica su tutti gli alunni. Il 2% degli alunni ha svolto un esame finale, con riconoscimento di 2 CFU. Esso prevedeva una relazione scritta e la discussione davanti ad una commissione composta dall’insegnante di riferimento e dalla responsabile dell’attività PLS. Buona parte dei partecipanti ha compilato il questionario sul grado di interesse e di soddisfazione. L’andamento crescente nel tempo del numero di alunni partecipanti (fino a 800 l’anno) è coerente con le impressioni raccolte da testimonianze degli insegnanti: gli alunni che hanno partecipato all’attività PLS hanno successivamente svolto le verifiche di classe con maggiore profitto.

This study takes the first step toward in situ analysis of powder drugs which does not require any alteration of the samples. A fast, inexpensive analytical method based on reflectance near-infrared spectrometry and multivariate calibration was applied. Samples were laboratory-prepared ternary powders (diacetylmorphine, caffeine, and paracetamol) chosen through a D-optimal experimental design. Partial least squares regression was applied.

Pirolisi analitica e analisi chemiometrica per la rapida classificazione di specie batteriche utilizzando gli acidi grassi come biomarkers

Calibrazione multivariata basata sul metodo PLS per la determinazione quantitativa di esplosivi e droghe mediante voltammetria

Si verifica un metodo per la determinazione dell’intervallo di confidenza nel caso di interpolazione su modello multivariato basato su spettri NIR di droghe solide.

Fattibilità dell'utilizzo della DAD-NIR in riflettanza per l'analisi non alterativa e in-situ di droghe solide da sequestro

Il presente lavoro, riguarda la determinazione di Pt(II), Pd(II), Rh(III) e Pb(II) mediante voltammetria di ridissoluzione anodica ad onda quadra (SWASV). La procedura analitica è stata verificata mediante l’analisi di materiali standard di riferimento. La precisione e l’accuratezza, espresse rispettivamente come deviazione standard relativa ed errore relativo, sono risultate inferiori al 6 % in tutti i casi. Viene valutata la possibilità di usare l’area di picco come parametro strumentale1. Sono valutate inoltre le possibili interferenze2. Una volta messa a punto su soluzioni acquose di riferimento e verificata su materiali standard di riferimento, la procedura analitica proposta è stata trasferita ed applicata su campioni reali prelevati in ecosistemi diversamente influenzati dal traffico veicolare. Nel presente lavoro viene anche discusso un confronto critico con misure spettroscopiche effettuate sugli stessi campioni. 1. C. Locatelli, C. Electroanalysis 2003, 15, 1397-1402. 2. C. Locatelli, C.; G. Torsi, G. J. of Electroanal. Chem. 2001, 509, 80-89.

Il numero di immatricolazioni ai corsi di studio universitari in ambito scientifico è andato calando negli ultimi anni, con conseguente scarsità di laureati in alcuni ambiti lavorativi e di ricerca. Per esempio da una recente indagine di Federchimica risulta che il turnover di lavoratori del settore chimico è insufficiente per carenza di laureati in chimica. Il Progetto Lauree Scientifiche nasce per iniziativa del MIUR, degli Atenei, degli Uffici Regionali Scolastici e di Confindustria. Tale progetto ha l’obiettivo di portare studenti ed insegnanti delle Scuole dentro l’Università, per seguire brevi e strutturati percorsi formativi. Tali percorsi possono portare a riconoscimenti ufficiali, quali ad esempio conseguimento di Crediti Formativi Universitari. In questo lavoro si descrivono il percorso formativo e le lezioni ed esercitazioni proposte nell’ambito della linea di azione: “Esercitazioni di laboratorio per studenti: Chimica e Indagini di Polizia Scientifica”. Si propone poi un resoconto sulla risposta da parte di studenti ed insegnanti: schede di valutazione e risultati delle verifiche di profitto.

Biocompatible methods capable of rapid purification and fractionation of analytes from complex natural matrices are increasingly in demand, particularly at the forefront of biotechnological applications. Fieldflow fractionation is a separation technique suitable for nano-sized and micro-sized analytes among which bioanalytes are an important family. The objective of this preliminary study is to start a more general approach to field-flow fractionation for bio-samples by investigation of the correlation between channel surface composition and biosample adhesion. For the first time we report on the use of X-ray photoelectron spectroscopy (XPS) to study the surface properties of channels of known performance. By XPS, a polar hydrophobic environment was found on PVC material commonly used as accumulation wall in gravitational field-flow fractionation (GrFFF), which explains the low recovery obtained when GrFFF was used to fractionate a biological sample such as Staphylococcus aureus. An increase in separation performance was obtained first by conditioning the accumulation wall with bovine serum albumin and then by using the ion-beam sputtering technique to cover the GrFFF channel surface with a controlled inert film. XPS analysis was also employed to determine the composition of membranes used in hollow-fiber flow fieldflow fractionation (HF FlFFF). The results obtained revealed homogeneous composition along the HF FlFFF channel both before and after its use for fractionation of an intact protein such as ferritin.

Appunti di lezione per l’insegnamento di Chemiometria del corso di laurea di II livello in Metodologie Chimiche Avanzate della Facoltà di Scienze di Bologna. L’autrice del presente testo è responsabile didattico del suddetto insegnamento da quando esso è stato istituito ovvero dall’anno accademico 2005-2006. Questi “appunti” sono basati sul testo di riferimento (1) e sono il frutto di un paziente lavoro di riassunto, riscrittura e semplificazione di tutte e sole le parti del testo di riferimento che vengono trattate ed applicate nel corso di Chemiometria. L’obiettivo dell’autrice nello scrivere questi appunti è stato quello di fornire agli studenti un “prontuario” semplice ma non banale, conciso ma completo ed esauriente per affrontare i problemi multivariati di interesse chimico-analitico. Per affrontare lo studio dei presenti appunti, chi legge deve avere le conoscenze di base acquisibili negli insegnamenti di Chimica Analitica e di Laboratorio di Chimica Analitica II del corso di laurea di I livello in Chimica della Facoltà di Scienze di Bologna. Tali conoscenze sono acquisibili anche consultando i riferimenti bibliografici (2) e (3). (1) Roberto Todeschini, Introduzione alla chemiometria, Edises, 1998 (2) J. C. Miller, J. N. Miller - Statistics For Analytical Chemistry - John Wiley & Sons, NewYork, 1984 (3) Skoog, West, Holler, Crouch- Fondamenti di Chimica Analitica - EdiSES srl, Napoli, 2005