The Museo Nazionale della Scienza e della Tecnologia “Leonardo da Vinci” in Milan is exposing two... more The Museo Nazionale della Scienza e della Tecnologia “Leonardo da Vinci” in Milan is exposing two pairs of canal lock gates, used to control the water flow in Milan canal system, whose design appears in the Leonardo’s Codex Atlanticus. The wood present in the gates has been deeply characterised by mean of a multidisciplinary investigation involving i) DNA barcoding of wood fragments; ii) microbial community characterisation, and iii) chemical analyses. DNA barcoding revealed that two fragments of the gates belonged to wood species widely used in the middle age: Fagus sylvatica and Picea abies. The chemical characterisations were based on the use of ionic liquid as dissolving medium in order to analyse the entire cell wall material by means of Gel Permeation Chromatography (GPC) and 2D-NMR-HSQC techniques. This multidisciplinary analytical approach was able to highlight the complex nature of the degradation occurred during the gate operation (XVI-XVIII centuries): an intricate interp...
According to the 2021 World Drug Report, around 275 million people use drugs of abuse, and 36 mil... more According to the 2021 World Drug Report, around 275 million people use drugs of abuse, and 36 million people suffer from addiction, fostering a thriving market for illicit substances. In Italy, 30,083 people were reported to the Judicial Authority for offenses in violation of the Italian Law D.P.R. 309/1990. These offences are sentenced after a qualitative–quantitative analysis of seized materials. Given the large quantity of seized drugs and the need to perform accurate analytical determinations, Italian forensic laboratories struggle to complete analyses in a short time, delaying the entire reporting process needed to achieve sentencing. For this purpose, an UHPLC-MS/MS-based platform was developed at the University of Milano-Bicocca to support law-enforcement authorities. Software was designed to easily manage street seizure acquisition, documentation registration, and sampling. A sensitive UHPLC-MS/MS method was fully validated for the quantification of the traditional illicit s...
Optical emission spectroscopy was used to characterize the gas phase in a gliding arc tornado rea... more Optical emission spectroscopy was used to characterize the gas phase in a gliding arc tornado reactor used for plasma applications. Results concerning the transition between spark and fully developed arc regimes are presented, by comparing with the electrical characteristics of the discharge. An extended analysis of spectra of air and helium discharges mixed with water and hexamethyldisiloxane vapors was performed, with the identification of active radical species involved in the surface functionalization of polymeric nanoparticles. Graphic abstract
Neural networks are rapidly gaining popularity in chemical modeling and Quantitative Structure–Ac... more Neural networks are rapidly gaining popularity in chemical modeling and Quantitative Structure–Activity Relationship (QSAR) thanks to their ability to handle multitask problems. However, outcomes of neural networks depend on the tuning of several hyperparameters, whose small variations can often strongly affect their performance. Hence, optimization is a fundamental step in training neural networks although, in many cases, it can be very expensive from a computational point of view. In this study, we compared four of the most widely used approaches for tuning hyperparameters, namely, grid search, random search, tree-structured Parzen estimator, and genetic algorithms on three multitask QSAR datasets. We mainly focused on parsimonious optimization and thus not only on the performance of neural networks, but also the computational time that was taken into account. Furthermore, since the optimization approaches do not directly provide information about the influence of hyperparameters,...
Aromatics with polar substituents such as phenol, benzoic acid, nitrophenols, nitrocresols and ot... more Aromatics with polar substituents such as phenol, benzoic acid, nitrophenols, nitrocresols and others have been found in concentrations in the jig L"* range in the Rhein-Ruhr area in western Germany and in urban Los Angeles rain (Hansen et aL, 1991). Aqueous phase nitration of aromatics may lead to the production of harmful products. Several reports are available related to the toxicity of nitrophenols to organisms. While there is considerable evidence for the occurrence of aromatic and nitroaromatic compounds in cloud and rainwater, different possibilities exist with regard to the origin of the latter compounds. Aromatic nitroderivatives may either be directly emitted from anthropogenic sources, they may be formed by tropospheric gas phase reactions and finally they may be formed within the tropospheric aqueous phase. Whereas the assessment of emissions of harmful compounds such as nitroaromatics represents an environmental research issue by itself, some gas phase studies of n...
Their physicochemical properties and relatively low cost make cellulose nanocrystals (CNCs) a pot... more Their physicochemical properties and relatively low cost make cellulose nanocrystals (CNCs) a potential candidate for future large-scale production in many fields including nanomedicine. Prior to a sustained and responsible development as theranostic agents, robust and reliable data concerning their safety, biocompatibility, and tissue distribution should be provided. In the present study, CNCs were extracted from Whatman filters functionalized with a fluorescent dye, and their interaction with living organisms has been thoroughly assessed. Our experimental evidence demonstrated that CNCs (1) are well tolerated by healthy mice after systemic injection; (2) are rapidly excreted, thus avoiding bioaccumulation in filter organs such as the kidneys and liver; (3) transiently migrate in bones; and (4) are able to penetrate in the cytoplasm of cancer cells without inducing material-related detrimental effects in terms of cell survival. Our results strongly suggest that the peculiar tropism...
Wood artefacts undergo complex alteration and degradation during ageing, and gaining information ... more Wood artefacts undergo complex alteration and degradation during ageing, and gaining information on the chemical composition of wood in archaeological artefacts is fundamental to plan conservation strategies. In this work, an integrated analytical approach based on innovative NMR spectroscopy procedures, gel permeation chromatography and analytical pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC-MS) was applied for the first time on archaeological wood from the Oseberg collection (Norway), in order to evaluate the chemical state of preservation of the wood components, without separating them. We adopted ionic liquids (ILs) as non-derivatising solvents, thus obtaining an efficient dissolution of the wood, allowing us to overcome the difficulty of dissolving wood in its native form in conventional molecular solvents. Highly substituted lignocellulosic esters were therefore obtained under mild conditions by reacting the solubilised wood with either acetyl chloride or...
The octocoral family Alcyoniidae represents a rich source of bioactive substances with intriguing... more The octocoral family Alcyoniidae represents a rich source of bioactive substances with intriguing and unique structural features. This review aims to provide an updated overview of the compounds isolated from Alcyoniidae and displaying potential cytotoxic activity. In order to allow a better comparison among the bioactive compounds, we focused on molecules evaluated in vitro by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, by far the most widely used method to analyze cell proliferation and viability. Specifically, we surveyed the last thirty years of research, finding 153 papers reporting on 344 compounds with proven cytotoxicity. The data were organized in tables to provide a ranking of the most active compounds, to be exploited for the selection of the most promising candidates for further screening and pre-clinical evaluation as anti-cancer agents. Specifically, we found that (22S,24S)-24-methyl-22,25-epoxyfurost-5-ene-3β,20β-diol (16), ...
Increasing the profitability of lignin side-streams is a challenge in the scientific community. L... more Increasing the profitability of lignin side-streams is a challenge in the scientific community. Lignin residue originates from black liquor and lignin cake, which are residues from pulp and bio-ethanol production. This paper presents a life cycle assessment study to investigate how pulp and bio-ethanol processes vary in their environmental performance when a fraction of lignin is removed and to identify the best alternative energy source. Fossil energy, natural gas, and cogeneration were evaluated as heat and power alternative sources. The results showed that lignin removal does not considerably affect the environmental performance of the baseline systems and does not generate a relevant risk of “burdens shifting.” Natural gas was the best alternative of power source in a bio-ethanol system, whereas cogeneration showed better compatibility with pulp mills. For the analyzed systems, the necessary allocation distributed the impact contributions between the main products (bio-ethanol/p...
Liquid chromatography coupled to a photodiode array detector and atmosphericpressure chemical ion... more Liquid chromatography coupled to a photodiode array detector and atmosphericpressure chemical ionization ion sources were used for the determination of a variety of nitrophenols in air samples after solid phase extraction using silica gel and XAD-7 resin-absorbents (rainwater), In order to predict the toxicity of these relevtmt compounds on animals we determined in vitro both the uncoupling activity of the ox\dative phosphorylation and the inhibitory effect of oxygen consumption in mammalian mitochondria for 18 available phenol derivatives. The experimental data were modelled in a QSAR approach using theoretical molecular descriptors,
The OHand the NOs-initiated oxidation of aromatic hydrocarbons are major sinks for these species,... more The OHand the NOs-initiated oxidation of aromatic hydrocarbons are major sinks for these species, observed in high concentrations in urban areas. This demands a better knowledge of mechanisms and reaction products. The plot of log k (six compounds) for para-substituted toluenes vs Hammett's p for the reaction with OH has a p = 2.3 ± 0.2; r% = 0.96. This is in line with the known rate-determining addition of OH involving a polar transition state. The analogous plot with NOs (nine compounds) gives p = 4.3 ± 0.6; r% = 0.87. This negative value suggests again a polar transition state very similar to that occurring with OH and indicates a rate-determining addition for this reaction. Unrestricted Hartree-Foch (UHF)-Austin Model 1 (AMI) calculations suggest that the isomeric cyclohexadienyl radicals formed in the addition of OH or NO] to toluene and xylenes have similar stability, with the exception of the "ipso" adduct, which is less stable. The adducts formed by addition of...
The Museo Nazionale della Scienza e della Tecnologia “Leonardo da Vinci” in Milan is exposing two... more The Museo Nazionale della Scienza e della Tecnologia “Leonardo da Vinci” in Milan is exposing two pairs of canal lock gates, used to control the water flow in Milan canal system, whose design appears in the Leonardo’s Codex Atlanticus. The wood present in the gates has been deeply characterised by mean of a multidisciplinary investigation involving i) DNA barcoding of wood fragments; ii) microbial community characterisation, and iii) chemical analyses. DNA barcoding revealed that two fragments of the gates belonged to wood species widely used in the middle age: Fagus sylvatica and Picea abies. The chemical characterisations were based on the use of ionic liquid as dissolving medium in order to analyse the entire cell wall material by means of Gel Permeation Chromatography (GPC) and 2D-NMR-HSQC techniques. This multidisciplinary analytical approach was able to highlight the complex nature of the degradation occurred during the gate operation (XVI-XVIII centuries): an intricate interp...
According to the 2021 World Drug Report, around 275 million people use drugs of abuse, and 36 mil... more According to the 2021 World Drug Report, around 275 million people use drugs of abuse, and 36 million people suffer from addiction, fostering a thriving market for illicit substances. In Italy, 30,083 people were reported to the Judicial Authority for offenses in violation of the Italian Law D.P.R. 309/1990. These offences are sentenced after a qualitative–quantitative analysis of seized materials. Given the large quantity of seized drugs and the need to perform accurate analytical determinations, Italian forensic laboratories struggle to complete analyses in a short time, delaying the entire reporting process needed to achieve sentencing. For this purpose, an UHPLC-MS/MS-based platform was developed at the University of Milano-Bicocca to support law-enforcement authorities. Software was designed to easily manage street seizure acquisition, documentation registration, and sampling. A sensitive UHPLC-MS/MS method was fully validated for the quantification of the traditional illicit s...
Optical emission spectroscopy was used to characterize the gas phase in a gliding arc tornado rea... more Optical emission spectroscopy was used to characterize the gas phase in a gliding arc tornado reactor used for plasma applications. Results concerning the transition between spark and fully developed arc regimes are presented, by comparing with the electrical characteristics of the discharge. An extended analysis of spectra of air and helium discharges mixed with water and hexamethyldisiloxane vapors was performed, with the identification of active radical species involved in the surface functionalization of polymeric nanoparticles. Graphic abstract
Neural networks are rapidly gaining popularity in chemical modeling and Quantitative Structure–Ac... more Neural networks are rapidly gaining popularity in chemical modeling and Quantitative Structure–Activity Relationship (QSAR) thanks to their ability to handle multitask problems. However, outcomes of neural networks depend on the tuning of several hyperparameters, whose small variations can often strongly affect their performance. Hence, optimization is a fundamental step in training neural networks although, in many cases, it can be very expensive from a computational point of view. In this study, we compared four of the most widely used approaches for tuning hyperparameters, namely, grid search, random search, tree-structured Parzen estimator, and genetic algorithms on three multitask QSAR datasets. We mainly focused on parsimonious optimization and thus not only on the performance of neural networks, but also the computational time that was taken into account. Furthermore, since the optimization approaches do not directly provide information about the influence of hyperparameters,...
Aromatics with polar substituents such as phenol, benzoic acid, nitrophenols, nitrocresols and ot... more Aromatics with polar substituents such as phenol, benzoic acid, nitrophenols, nitrocresols and others have been found in concentrations in the jig L"* range in the Rhein-Ruhr area in western Germany and in urban Los Angeles rain (Hansen et aL, 1991). Aqueous phase nitration of aromatics may lead to the production of harmful products. Several reports are available related to the toxicity of nitrophenols to organisms. While there is considerable evidence for the occurrence of aromatic and nitroaromatic compounds in cloud and rainwater, different possibilities exist with regard to the origin of the latter compounds. Aromatic nitroderivatives may either be directly emitted from anthropogenic sources, they may be formed by tropospheric gas phase reactions and finally they may be formed within the tropospheric aqueous phase. Whereas the assessment of emissions of harmful compounds such as nitroaromatics represents an environmental research issue by itself, some gas phase studies of n...
Their physicochemical properties and relatively low cost make cellulose nanocrystals (CNCs) a pot... more Their physicochemical properties and relatively low cost make cellulose nanocrystals (CNCs) a potential candidate for future large-scale production in many fields including nanomedicine. Prior to a sustained and responsible development as theranostic agents, robust and reliable data concerning their safety, biocompatibility, and tissue distribution should be provided. In the present study, CNCs were extracted from Whatman filters functionalized with a fluorescent dye, and their interaction with living organisms has been thoroughly assessed. Our experimental evidence demonstrated that CNCs (1) are well tolerated by healthy mice after systemic injection; (2) are rapidly excreted, thus avoiding bioaccumulation in filter organs such as the kidneys and liver; (3) transiently migrate in bones; and (4) are able to penetrate in the cytoplasm of cancer cells without inducing material-related detrimental effects in terms of cell survival. Our results strongly suggest that the peculiar tropism...
Wood artefacts undergo complex alteration and degradation during ageing, and gaining information ... more Wood artefacts undergo complex alteration and degradation during ageing, and gaining information on the chemical composition of wood in archaeological artefacts is fundamental to plan conservation strategies. In this work, an integrated analytical approach based on innovative NMR spectroscopy procedures, gel permeation chromatography and analytical pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC-MS) was applied for the first time on archaeological wood from the Oseberg collection (Norway), in order to evaluate the chemical state of preservation of the wood components, without separating them. We adopted ionic liquids (ILs) as non-derivatising solvents, thus obtaining an efficient dissolution of the wood, allowing us to overcome the difficulty of dissolving wood in its native form in conventional molecular solvents. Highly substituted lignocellulosic esters were therefore obtained under mild conditions by reacting the solubilised wood with either acetyl chloride or...
The octocoral family Alcyoniidae represents a rich source of bioactive substances with intriguing... more The octocoral family Alcyoniidae represents a rich source of bioactive substances with intriguing and unique structural features. This review aims to provide an updated overview of the compounds isolated from Alcyoniidae and displaying potential cytotoxic activity. In order to allow a better comparison among the bioactive compounds, we focused on molecules evaluated in vitro by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, by far the most widely used method to analyze cell proliferation and viability. Specifically, we surveyed the last thirty years of research, finding 153 papers reporting on 344 compounds with proven cytotoxicity. The data were organized in tables to provide a ranking of the most active compounds, to be exploited for the selection of the most promising candidates for further screening and pre-clinical evaluation as anti-cancer agents. Specifically, we found that (22S,24S)-24-methyl-22,25-epoxyfurost-5-ene-3β,20β-diol (16), ...
Increasing the profitability of lignin side-streams is a challenge in the scientific community. L... more Increasing the profitability of lignin side-streams is a challenge in the scientific community. Lignin residue originates from black liquor and lignin cake, which are residues from pulp and bio-ethanol production. This paper presents a life cycle assessment study to investigate how pulp and bio-ethanol processes vary in their environmental performance when a fraction of lignin is removed and to identify the best alternative energy source. Fossil energy, natural gas, and cogeneration were evaluated as heat and power alternative sources. The results showed that lignin removal does not considerably affect the environmental performance of the baseline systems and does not generate a relevant risk of “burdens shifting.” Natural gas was the best alternative of power source in a bio-ethanol system, whereas cogeneration showed better compatibility with pulp mills. For the analyzed systems, the necessary allocation distributed the impact contributions between the main products (bio-ethanol/p...
Liquid chromatography coupled to a photodiode array detector and atmosphericpressure chemical ion... more Liquid chromatography coupled to a photodiode array detector and atmosphericpressure chemical ionization ion sources were used for the determination of a variety of nitrophenols in air samples after solid phase extraction using silica gel and XAD-7 resin-absorbents (rainwater), In order to predict the toxicity of these relevtmt compounds on animals we determined in vitro both the uncoupling activity of the ox\dative phosphorylation and the inhibitory effect of oxygen consumption in mammalian mitochondria for 18 available phenol derivatives. The experimental data were modelled in a QSAR approach using theoretical molecular descriptors,
The OHand the NOs-initiated oxidation of aromatic hydrocarbons are major sinks for these species,... more The OHand the NOs-initiated oxidation of aromatic hydrocarbons are major sinks for these species, observed in high concentrations in urban areas. This demands a better knowledge of mechanisms and reaction products. The plot of log k (six compounds) for para-substituted toluenes vs Hammett's p for the reaction with OH has a p = 2.3 ± 0.2; r% = 0.96. This is in line with the known rate-determining addition of OH involving a polar transition state. The analogous plot with NOs (nine compounds) gives p = 4.3 ± 0.6; r% = 0.87. This negative value suggests again a polar transition state very similar to that occurring with OH and indicates a rate-determining addition for this reaction. Unrestricted Hartree-Foch (UHF)-Austin Model 1 (AMI) calculations suggest that the isomeric cyclohexadienyl radicals formed in the addition of OH or NO] to toluene and xylenes have similar stability, with the exception of the "ipso" adduct, which is less stable. The adducts formed by addition of...
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Papers by Marco Orlandi