Chalcone is an important biosynthetic precursor, due to the diverse pharmacological activities. The aim of this current study was to synthesize 14 new chalcone derivatives compounds by incorporating p-alkoxyacetophenones with substituted benzaldehydes. Two new series of chalcone derivatives have been synthesized using the alkylation and the base catalysed Claisen-Schmidt condensation. All the synthesized compounds were fully characterized by IR, 1D NMR (1H and 13C NMR) and 2D NMR (COSY, HMQC, HMBC) as well as mass spectrometry analysis. All the synthesized compounds were assayed in vitro for their antituberculosis activities against Mycobacterium tuberculosis strain. Among them, compounds (E)-1-[4-(heptoxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5a), (E)-1-[4-(octyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5b) and (E)-1-[4-(decyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5d) showed good activities with the lowest MIC value of 12.5 μg/mL.
{"title":"Synthesis of some chalcones derivatives series and their antituberculosis activity","authors":"Noviany Noviany, Hasnah Osman, Suriyati Mohamad, Sutopo Hadi, Heri Satria, Buhani Buhani","doi":"10.1515/pac-2023-1127","DOIUrl":"https://doi.org/10.1515/pac-2023-1127","url":null,"abstract":"Chalcone is an important biosynthetic precursor, due to the diverse pharmacological activities. The aim of this current study was to synthesize 14 new chalcone derivatives compounds by incorporating <jats:italic>p</jats:italic>-alkoxyacetophenones with substituted benzaldehydes. Two new series of chalcone derivatives have been synthesized using the alkylation and the base catalysed Claisen-Schmidt condensation. All the synthesized compounds were fully characterized by IR, 1D NMR (<jats:sup>1</jats:sup>H and <jats:sup>13</jats:sup>C NMR) and 2D NMR (COSY, HMQC, HMBC) as well as mass spectrometry analysis. All the synthesized compounds were assayed <jats:italic>in vitro</jats:italic> for their antituberculosis activities against <jats:italic>Mycobacterium tuberculosis</jats:italic> strain. Among them, compounds (<jats:italic>E</jats:italic>)-1-[4-(heptoxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5a), (<jats:italic>E</jats:italic>)-1-[4-(octyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5b) and (<jats:italic>E</jats:italic>)-1-[4-(decyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5d) showed good activities with the lowest MIC value of 12.5 μg/mL.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"171 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Silver and lanthanide (Tm3+, Yb3+) doped oxyfluoride glasses have been prepared by melt-quenching method. The absorption of the glasses was measured in the range from 350 to 550 nm revealing the absorption edges of Ag nanoclusters and Tm3+ transition. The photoluminescence spectra of the glasses were detected in the range from 400 to 1100 nm under excitation in the range from 300 to 500 nm. The photoluminescence excitation spectra showed that Ag nanoclusters and Tm3+ ions can effectively harvest energy in UV-range and convert to visible and infrared (through emission by Yb3+ ions) ranges making the glasses perspective as white light emitters and solar spectrum downconverters.
{"title":"Luminescence of silver, thulium and ytterbium doped oxyfluoride glasses","authors":"Mikhail V. Shestakov, Victor V. Moshchalkov","doi":"10.1515/pac-2023-1106","DOIUrl":"https://doi.org/10.1515/pac-2023-1106","url":null,"abstract":"Silver and lanthanide (Tm<jats:sup>3+</jats:sup>, Yb<jats:sup>3+</jats:sup>) doped oxyfluoride glasses have been prepared by melt-quenching method. The absorption of the glasses was measured in the range from 350 to 550 nm revealing the absorption edges of Ag nanoclusters and Tm<jats:sup>3+</jats:sup> transition. The photoluminescence spectra of the glasses were detected in the range from 400 to 1100 nm under excitation in the range from 300 to 500 nm. The photoluminescence excitation spectra showed that Ag nanoclusters and Tm<jats:sup>3+</jats:sup> ions can effectively harvest energy in UV-range and convert to visible and infrared (through emission by Yb<jats:sup>3+</jats:sup> ions) ranges making the glasses perspective as white light emitters and solar spectrum downconverters.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"115 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giuseppe Resnati, David L. Bryce, Gautam R. Desiraju, Antonio Frontera, Ingo Krossing, Anthony C. Legon, Pierangelo Metrangolo, Francesco Nicotra, Kari Rissanen, Steve Scheiner, Giancarlo Terraneo
This recommendation proposes a definition for the term “pnictogen bond”; the term pnictogen bond designates a subset of the attractive interactions between an electrophilic region on a pnictogen atom in a molecular entity and a nucleophilic region in another, or the same, molecular entity.
{"title":"Definition of the pnictogen bond (IUPAC Recommendations 2023)","authors":"Giuseppe Resnati, David L. Bryce, Gautam R. Desiraju, Antonio Frontera, Ingo Krossing, Anthony C. Legon, Pierangelo Metrangolo, Francesco Nicotra, Kari Rissanen, Steve Scheiner, Giancarlo Terraneo","doi":"10.1515/pac-2020-1002","DOIUrl":"https://doi.org/10.1515/pac-2020-1002","url":null,"abstract":"This recommendation proposes a definition for the term “pnictogen bond”; the term pnictogen bond designates a subset of the attractive interactions between an <jats:italic>electrophilic</jats:italic> region on a <jats:italic>pnictogen</jats:italic> atom in a <jats:italic>molecular entity</jats:italic> and a <jats:italic>nucleophilic</jats:italic> region in another, or the same, molecular entity.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"383 2 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is widely recognized that electrostatics plays a central role in the intermolecular interactions in condensed phases, as evidenced by the “electrostatics + Lennard-Jones” form of the potential functions that are commonly used in classical molecular dynamics simulations. Then, do we understand all about electrostatics in condensed phases? In this review, recent theoretical advances in relation to this topic will be discussed: (1) vibrational spectroscopic probing of the electrostatics in condensed phases, and (2) some phenomena affected by deviation from the scheme of isotropic fixed atomic partial charges, i.e., anisotropy and intermolecular transfer of electron distributions. A theoretical basis for better understanding on them and some theoretical models for practical calculations will be shown with some typical example cases of hydrogen- and halogen-bonded systems.
{"title":"Roles of electrostatics and intermolecular electronic motions in the structural and spectroscopic features of hydrogen- and halogen-bonded systems","authors":"Hajime Torii","doi":"10.1515/pac-2023-1202","DOIUrl":"https://doi.org/10.1515/pac-2023-1202","url":null,"abstract":"It is widely recognized that electrostatics plays a central role in the intermolecular interactions in condensed phases, as evidenced by the “electrostatics + Lennard-Jones” form of the potential functions that are commonly used in classical molecular dynamics simulations. Then, do we understand all about electrostatics in condensed phases? In this review, recent theoretical advances in relation to this topic will be discussed: (1) vibrational spectroscopic probing of the electrostatics in condensed phases, and (2) some phenomena affected by deviation from the scheme of isotropic fixed atomic partial charges, <jats:italic>i.e.</jats:italic>, anisotropy and intermolecular transfer of electron distributions. A theoretical basis for better understanding on them and some theoretical models for practical calculations will be shown with some typical example cases of hydrogen- and halogen-bonded systems.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"72 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139510064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Poly(ethylene terephthalate) (PET) is a widely used thermoplastic polymer with exceptional properties, making it a cornerstone in various industries. However, the extensive global demand for PET, particularly in the packaging sector, has led to significant ecological concerns due to inadequate recycling rates. This paper explores the potential of Meldrum’s acid-based chain extenders as a solution to enhance PET recycling. Initially, 2,2,5-trimethyl-5-(4-vinylbenzyl)-1,3-dioxane-4,6-dione (St-MA) was synthesized, and its homopolymers were produced through free radical polymerization and characterized through 1H NMR, FTIR and TGA analyses. Dynamic interactions between recycled PET (rPET) and the synthesized chain extender (HP) in an extrusion environment was further explored, resulting in higher Tg and Tc for rPET when 0.5 wt% of HP was added as a reactive chain extender. The chemical tunability of this functional ketene-based chain extender holds promise to enhance PET recycling practices. The continuous evolution of regulatory frameworks and environmental concerns may prompt the exploration of novel approaches, such as tailored Meldrum’s acid-bearing chain extenders, which might have the potential to reduce the ecological consequences associated with post-consumer PET waste.
聚对苯二甲酸乙二醇酯（PET）是一种广泛使用的热塑性聚合物，其优异的性能使其成为各行各业的基石。然而，全球对 PET 的广泛需求，尤其是在包装领域，却因回收率不足而引发了严重的生态问题。本文探讨了美杜伦酸基扩链剂作为提高 PET 回收利用率的解决方案的潜力。首先合成了 2,2,5-三甲基-5-(4-乙烯基苄基)-1,3-二恶烷-4,6-二酮（St-MA），然后通过自由基聚合生产了其均聚物，并通过 1H NMR、FTIR 和 TGA 分析对其进行了表征。进一步探讨了再生 PET（rPET）和合成的扩链剂（HP）在挤出环境中的动态相互作用，结果发现当添加 0.5 wt%的 HP 作为活性扩链剂时，rPET 的 T g 和 T c 都较高。这种功能性酮基扩链剂的化学可调性为改进 PET 回收利用实践带来了希望。监管框架和环境问题的不断演变可能会促使人们探索新的方法，例如量身定制的 Meldrum 含酸扩链剂，这种方法有可能减少与消费后 PET 废弃物相关的生态后果。
{"title":"Exploring the potential of Meldrum’s acid-bearing chain extenders for mechanical recycling of PET","authors":"Yonca Alkan Goksu","doi":"10.1515/pac-2023-1123","DOIUrl":"https://doi.org/10.1515/pac-2023-1123","url":null,"abstract":"Poly(ethylene terephthalate) (PET) is a widely used thermoplastic polymer with exceptional properties, making it a cornerstone in various industries. However, the extensive global demand for PET, particularly in the packaging sector, has led to significant ecological concerns due to inadequate recycling rates. This paper explores the potential of Meldrum’s acid-based chain extenders as a solution to enhance PET recycling. Initially, 2,2,5-trimethyl-5-(4-vinylbenzyl)-1,3-dioxane-4,6-dione (St-MA) was synthesized, and its homopolymers were produced through free radical polymerization and characterized through <jats:sup>1</jats:sup>H NMR, FTIR and TGA analyses. Dynamic interactions between recycled PET (rPET) and the synthesized chain extender (HP) in an extrusion environment was further explored, resulting in higher <jats:italic>T</jats:italic> <jats:sub>g</jats:sub> and <jats:italic>T</jats:italic> <jats:sub>c</jats:sub> for rPET when 0.5 wt% of HP was added as a reactive chain extender. The chemical tunability of this functional ketene-based chain extender holds promise to enhance PET recycling practices. The continuous evolution of regulatory frameworks and environmental concerns may prompt the exploration of novel approaches, such as tailored Meldrum’s acid-bearing chain extenders, which might have the potential to reduce the ecological consequences associated with post-consumer PET waste.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"35 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139496605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antonio Possolo, David Brynn Hibbert, Jürgen Stohner, Olha Bodnar, Juris Meija
This Brief Guide reintroduces readers to the main concepts and technical tools used for the evaluation and expression of measurement uncertainty, including both classical and Bayesian statistical methods. The general approach is the same that was adopted by the Guide to the Expression of Uncertainty in Measurement (GUM): quantities whose values are surrounded by uncertainty are modeled as random variables, which enables the application of a wide range of techniques from probability and statistics to the evaluation of measurement uncertainty. All the methods presented are illustrated with examples involving real measurement results from a wide range of fields of chemistry and related sciences, ranging from classical analytical chemistry as practiced at the beginning to the 20th century, to contemporary studies of isotopic compositions of the elements and clinical trials. The supplementary material offers profusely annotated computer codes that allow the readers to reproduce all the calculations underlying the results presented in the examples.
{"title":"A brief guide to measurement uncertainty (IUPAC Technical Report)","authors":"Antonio Possolo, David Brynn Hibbert, Jürgen Stohner, Olha Bodnar, Juris Meija","doi":"10.1515/pac-2022-1203","DOIUrl":"https://doi.org/10.1515/pac-2022-1203","url":null,"abstract":"This <jats:italic>Brief Guide</jats:italic> reintroduces readers to the main concepts and technical tools used for the evaluation and expression of measurement uncertainty, including both classical and Bayesian statistical methods. The general approach is the same that was adopted by the <jats:italic>Guide to the Expression of Uncertainty in Measurement</jats:italic> (GUM): quantities whose values are surrounded by uncertainty are modeled as random variables, which enables the application of a wide range of techniques from probability and statistics to the evaluation of measurement uncertainty. All the methods presented are illustrated with examples involving real measurement results from a wide range of fields of chemistry and related sciences, ranging from classical analytical chemistry as practiced at the beginning to the 20th century, to contemporary studies of isotopic compositions of the elements and clinical trials. The supplementary material offers profusely annotated computer codes that allow the readers to reproduce all the calculations underlying the results presented in the examples.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"31 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139496636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Madelaine S. Woodward, Danielle E. Runacres, Julian Grigg, Imtiaz Khan, William Levason, Graeme McRobbie, Gillian Reid
The manual radiofluorination and purification of [FeF3(BnMe2-tacn)] (tacn = 1,4,7-triazacyclononane) using 18F− in aqueous EtOH has been translated to a GE FASTLab™ automatic synthesis platform and optimised by conducting a series of low-activity radiolabelling experiments to explore the effects of varying the precursor concentration, temperature, heating time, addition of NaOAc buffer and EtOH:H2O ratio. The optimal conditions were determined to be 1 mg/mL of the precursor being heated at 120 °C for 10 min in 75 %:25 % EtOH:H2O containing 18F−, with elution using 10 mM NaOAc, giving 61 % radiochemical yield (RCY). These conditions were then employed with high-activity 18F− giving a 97 % radiochemical purity (RCP) at t = 0, which decreases by 22 % over 5 h. Sodium ascorbate, nicotinamide and p-benzoic acid (pABA) were then tested as potential radiostabilisers for this system, initially using low-activity 18F−. These experiments revealed very rapid defluorination of the radioproduct in the presence of sodium ascorbate. In contrast, both nicotinamide and pABA appear to be effective radiostabilisers, resulting in RCP values of 91 % and 89 %, respectively, after 2 h, which compare with an RCP of 81 % under analogous conditions at t = 2 h in their absence. High-activity experiments were then undertaken with addition of 5 mg/mL of nicotinamide, with a radio-active concentration (RAC) of 220 MBq/mL, giving RCY of 26 % and following purification, RCP values for the [Fe18FF2(BnMe2-tacn)] product of 97 % at t = 0 and 86 % after 3 h.
{"title":"Automating the production of [Fe18FF2(BnMe2-tacn)] and investigating radiostabilisers for use with high-activity [18F]F−","authors":"Madelaine S. Woodward, Danielle E. Runacres, Julian Grigg, Imtiaz Khan, William Levason, Graeme McRobbie, Gillian Reid","doi":"10.1515/pac-2023-1008","DOIUrl":"https://doi.org/10.1515/pac-2023-1008","url":null,"abstract":"The manual radiofluorination and purification of [FeF<jats:sub>3</jats:sub>(BnMe<jats:sub>2</jats:sub>-tacn)] (tacn = 1,4,7-triazacyclononane) using <jats:sup>18</jats:sup>F<jats:sup>−</jats:sup> in aqueous EtOH has been translated to a GE FASTLab™ automatic synthesis platform and optimised by conducting a series of low-activity radiolabelling experiments to explore the effects of varying the precursor concentration, temperature, heating time, addition of NaOAc buffer and EtOH:H<jats:sub>2</jats:sub>O ratio. The optimal conditions were determined to be 1 mg/mL of the precursor being heated at 120 °C for 10 min in 75 %:25 % EtOH:H<jats:sub>2</jats:sub>O containing <jats:sup>18</jats:sup>F<jats:sup>−</jats:sup>, with elution using 10 mM NaOAc, giving 61 % radiochemical yield (RCY). These conditions were then employed with high-activity <jats:sup>18</jats:sup>F<jats:sup>−</jats:sup> giving a 97 % radiochemical purity (RCP) at <jats:italic>t</jats:italic> = 0, which decreases by 22 % over 5 h. Sodium ascorbate, nicotinamide and <jats:italic>p</jats:italic>-benzoic acid (<jats:italic>p</jats:italic>ABA) were then tested as potential radiostabilisers for this system, initially using low-activity <jats:sup>18</jats:sup>F<jats:sup>−</jats:sup>. These experiments revealed very rapid defluorination of the radioproduct in the presence of sodium ascorbate. In contrast, both nicotinamide and <jats:italic>p</jats:italic>ABA appear to be effective radiostabilisers, resulting in RCP values of 91 % and 89 %, respectively, after 2 h, which compare with an RCP of 81 % under analogous conditions at <jats:italic>t</jats:italic> = 2 h in their absence. High-activity experiments were then undertaken with addition of 5 mg/mL of nicotinamide, with a radio-active concentration (RAC) of 220 MBq/mL, giving RCY of 26 % and following purification, RCP values for the [Fe<jats:sup>18</jats:sup>FF<jats:sub>2</jats:sub>(BnMe<jats:sub>2</jats:sub>-tacn)] product of 97 % at <jats:italic>t</jats:italic> = 0 and 86 % after 3 h.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139376401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Holger Schönherr, Sergey I. Druzhinin, Stephan Handschuh-Wang, Daniel Wesner
We report on the analysis of individual dye loaded block copolymer (BCP) vesicles via a combination of confocal laser scanning microscopy (CSLM)/fluorescence lifetime imaging microscopy (FLIM) on the one hand and atomic force microscopy (AFM) on the other hand. AFM measurements on ATTO 647N-loaded poly(styrene-block-poly(acrylic acid)) (PS115-b-PAA15) vesicles were carried out with high spatial resolution and afforded morphology and dimensions of BCP vesicles on solid substrates. By contrast the CSLM and FLIM data are diffraction limited, but from the time resolved fluorescence data information on the local vicinity of the reporter dye can be extracted. In the combined experiment individual dye-loaded vesicles and vesicle aggregates were discerned, analyzed metrologically by AFM and in more detail by CSLM and FLIM. On the basis of FLIM data the partitioning of the reporter dye was analyzed. The dye resides preferentially in the hydrophilic corona inside the vesicles. The dye concentration in the polymersome was about 90 times higher than in the solution used for encapsulation. These results underline that the combination of AFM with sensitive optical techniques, especially FLIM, is a promising approach for obtaining a deeper understanding of molecular interactions and nanoenvironments in supramolecular macromolecular structures and beyond.
{"title":"Analysis of individual nanoscale block copolymer vesicles by atomic force microscopy combined with time-resolved fluorescence microscopy","authors":"Holger Schönherr, Sergey I. Druzhinin, Stephan Handschuh-Wang, Daniel Wesner","doi":"10.1515/pac-2023-1006","DOIUrl":"https://doi.org/10.1515/pac-2023-1006","url":null,"abstract":"We report on the analysis of individual dye loaded block copolymer (BCP) vesicles via a combination of confocal laser scanning microscopy (CSLM)/fluorescence lifetime imaging microscopy (FLIM) on the one hand and atomic force microscopy (AFM) on the other hand. AFM measurements on ATTO 647N-loaded poly(styrene-<jats:italic>block</jats:italic>-poly(acrylic acid)) (PS<jats:sub>115</jats:sub>-<jats:italic>b</jats:italic>-PAA<jats:sub>15</jats:sub>) vesicles were carried out with high spatial resolution and afforded morphology and dimensions of BCP vesicles on solid substrates. By contrast the CSLM and FLIM data are diffraction limited, but from the time resolved fluorescence data information on the local vicinity of the reporter dye can be extracted. In the combined experiment individual dye-loaded vesicles and vesicle aggregates were discerned, analyzed metrologically by AFM and in more detail by CSLM and FLIM. On the basis of FLIM data the partitioning of the reporter dye was analyzed. The dye resides preferentially in the hydrophilic corona inside the vesicles. The dye concentration in the polymersome was about 90 times higher than in the solution used for encapsulation. These results underline that the combination of AFM with sensitive optical techniques, especially FLIM, is a promising approach for obtaining a deeper understanding of molecular interactions and nanoenvironments in supramolecular macromolecular structures and beyond.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"23 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139104642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The use of molecular hydrogen (H2) in the energy sector faces several technical and economic hurdles related to its chemical and physical properties, particularly volumetric energy density and mass. The production, transport and storage of hydrogen, both in gas and liquid form, are intrinsically inefficient and expensive. Moreover, the mass production of green hydrogen would preferably use surpluses of renewable electricity that will be largely available not before the next decade. To fulfill the great potential of H2 in the decarbonization of the global economy – which should greatly accelerate – applications must be carefully selected, favoring for instance hard-to-abate sectors with respect to low-temperature residential heating or long-distance transportation versus light duty vehicles. In the meantime, research on production, transportation and storage of H2 must substantially leap forward.
{"title":"Hydrogen as an energy carrier: constraints and opportunities","authors":"Nicola Armaroli, Elisa Bandini, Andrea Barbieri","doi":"10.1515/pac-2023-0801","DOIUrl":"https://doi.org/10.1515/pac-2023-0801","url":null,"abstract":"The use of molecular hydrogen (H<jats:sub>2</jats:sub>) in the energy sector faces several technical and economic hurdles related to its chemical and physical properties, particularly volumetric energy density and mass. The production, transport and storage of hydrogen, both in gas and liquid form, are intrinsically inefficient and expensive. Moreover, the mass production of green hydrogen would preferably use surpluses of renewable electricity that will be largely available not before the next decade. To fulfill the great potential of H<jats:sub>2</jats:sub> in the decarbonization of the global economy – which should greatly accelerate – applications must be carefully selected, favoring for instance hard-to-abate sectors with respect to low-temperature residential heating or long-distance transportation versus light duty vehicles. In the meantime, research on production, transportation and storage of H<jats:sub>2</jats:sub> must substantially leap forward.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"133 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139104945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This critical review explores the quantification, analysis, and detection of radionuclides in the environment using the diffusive gradients in thin films (DGT) technique. Radionuclides, unstable isotopes emitting ionising radiation, are present in the environment due to natural and anthropogenic sources for which concerns are raised about their impact on human health and ecosystems. DGT offers a unique passive sampling approach for understanding the behaviour of radionuclides and other trace elements. This review provides insights into method development, real case scenarios, advantages, limitations, and future perspectives of DGT in radionuclide analysis. In terms of method development, various isotopes have been analysed with varying significance based on origin, concentration, risks, and persistence. Notably, U, Th, Pu, Am, Cm, 99Tc, 226Ra, 137Cs, 134Cs, 232U, 237Np, and 152Eu have been measured, revealing their diverse roles in environmental radioactivity. Real case scenarios illustrate applications in uranium mining, water quality monitoring, and metal speciation studies, shedding light on mobility, bioavailability, and ecological impacts. DGT’s advantages include in-situ monitoring, time-averaged mean concentrations, and comprehensive speciation insights. Challenges include potential influences from biofouling, temperature changes and specifically the possible degradation of the binding and diffuse layer due to ionising radiation in long term exposures. In addition, the distinction between fully labile free metal ions and partially labile metal-ligand complexes introduces a potential limitation in the DGT technique, hence being an opportunity for future studies. Looking forward, DGT is expected to contribute to radiation dose modelling, environmental risk assessment, and water quality monitoring, with ongoing developments enhancing its utility and accuracy.
{"title":"A critical review of the quantification, analysis and detection of radionuclides in the environment using diffusive gradients in thin films (DGT): advances and perspectives","authors":"Leonardo Pantoja, Hemda Garelick","doi":"10.1515/pac-2023-0809","DOIUrl":"https://doi.org/10.1515/pac-2023-0809","url":null,"abstract":"This critical review explores the quantification, analysis, and detection of radionuclides in the environment using the diffusive gradients in thin films (DGT) technique. Radionuclides, unstable isotopes emitting ionising radiation, are present in the environment due to natural and anthropogenic sources for which concerns are raised about their impact on human health and ecosystems. DGT offers a unique passive sampling approach for understanding the behaviour of radionuclides and other trace elements. This review provides insights into method development, real case scenarios, advantages, limitations, and future perspectives of DGT in radionuclide analysis. In terms of method development, various isotopes have been analysed with varying significance based on origin, concentration, risks, and persistence. Notably, U, Th, Pu, Am, Cm, 99Tc, 226Ra, 137Cs, 134Cs, 232U, 237Np, and 152Eu have been measured, revealing their diverse roles in environmental radioactivity. Real case scenarios illustrate applications in uranium mining, water quality monitoring, and metal speciation studies, shedding light on mobility, bioavailability, and ecological impacts. DGT’s advantages include <jats:italic>in-situ</jats:italic> monitoring, time-averaged mean concentrations, and comprehensive speciation insights. Challenges include potential influences from biofouling, temperature changes and specifically the possible degradation of the binding and diffuse layer due to ionising radiation in long term exposures. In addition, the distinction between fully labile free metal ions and partially labile metal-ligand complexes introduces a potential limitation in the DGT technique, hence being an opportunity for future studies. Looking forward, DGT is expected to contribute to radiation dose modelling, environmental risk assessment, and water quality monitoring, with ongoing developments enhancing its utility and accuracy.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"114 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138823972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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