Fabrizio Malaspina, Federica D’Aloise, Marco Pazzi, Vincenzo Bennardo
The background and current studies in the area of fire investigation at the Turin Fire Department’s Forensic Laboratory. It is uncommon to find an investigation facility, and even less often within fire brigade headquarters, that uses GC-MS and GC-TOF extensively to look for accelerants. During 16 years of intense effort, the Turin Fire Department in Italy accomplished various research projects on the identification of flame accelerants and more in fire residues. This collaborative effort between academics and firefighters is unique. It is based on the perspectives of individuals who often fight fires before going on to investigation. The article will outline the study that was done, explain how advances in instrumentation have produced ever-better outcomes and the next steps in the foreseeable future.
{"title":"Fire fighters and mass spectrometry: from the world of combustion to the molecular ion","authors":"Fabrizio Malaspina, Federica D’Aloise, Marco Pazzi, Vincenzo Bennardo","doi":"10.1515/pac-2024-0020","DOIUrl":"https://doi.org/10.1515/pac-2024-0020","url":null,"abstract":"The background and current studies in the area of fire investigation at the Turin Fire Department’s Forensic Laboratory. It is uncommon to find an investigation facility, and even less often within fire brigade headquarters, that uses GC-MS and GC-TOF extensively to look for accelerants. During 16 years of intense effort, the Turin Fire Department in Italy accomplished various research projects on the identification of flame accelerants and more in fire residues. This collaborative effort between academics and firefighters is unique. It is based on the perspectives of individuals who often fight fires before going on to investigation. The article will outline the study that was done, explain how advances in instrumentation have produced ever-better outcomes and the next steps in the foreseeable future.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"178 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141506947","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 reactions of trans-[PtX2(pic)2] (pic = γ-picoline, X = Cl−, NO3−) with N-acetyl-l-cysteine (acSH) and glutathione (GSH) were monitored and followed by 1H and 195Pt NMR. In the reaction of trans-[Pt(pic)2(D2O)2](NO3)2 with acSH, in the 195Pt NMR spectra, the most intense peak observed was trans-[Pt(pic)2(acS)}2(µ-acS)]+ (3). The intermediate product which was not clearly seen in the spectra was formulated as trans-[Pt (pic)2(acS)(D2O)]+ (2), with the weaker peak one as trans-[Pt(pic)2(acS)2] (1). With GSH, the main product observed was trans-[Pt(pic)2(GS)2] (4), while the intermediate product was not observed during this study. In the reactions of trans-[PtCl2(pic)2] with acSH, besides complexes 1 and 3 formed, the formation of trans-[Pt(pic)2Cl(acS)] (6) was also observed in the NMR spectra, while when it was reacted with GSH, followed a similar course to that of with acSH, but more slowly.
{"title":"Reactions of trans-[PtX2(pic)2] (Pic = γ-PICOLINE, X = Cl−, NO3 −) with N-acetyl-l-cysteine and glutathione","authors":"Sutopo Hadi, Noviany Noviany, Yandri Yandri","doi":"10.1515/pac-2023-1206","DOIUrl":"https://doi.org/10.1515/pac-2023-1206","url":null,"abstract":"The reactions of <jats:italic>trans</jats:italic>-[PtX<jats:sub>2</jats:sub>(pic)<jats:sub>2</jats:sub>] (pic = γ-picoline, X = Cl<jats:sup>−</jats:sup>, NO<jats:sub>3</jats:sub> <jats:sup>−</jats:sup>) with N-acetyl-<jats:sc>l</jats:sc>-cysteine (acSH) and glutathione (GSH) were monitored and followed by <jats:sup>1</jats:sup>H and <jats:sup>195</jats:sup>Pt NMR. In the reaction of <jats:italic>trans</jats:italic>-[Pt(pic)<jats:sub>2</jats:sub>(D<jats:sub>2</jats:sub>O)<jats:sub>2</jats:sub>](NO<jats:sub>3</jats:sub>)<jats:sub>2</jats:sub> with acSH, in the <jats:sup>195</jats:sup>Pt NMR spectra, the most intense peak observed was <jats:italic>trans</jats:italic>-[Pt(pic)<jats:sub>2</jats:sub>(acS)}<jats:sub>2</jats:sub>(µ-acS)]<jats:sup>+</jats:sup> (3). The intermediate product which was not clearly seen in the spectra was formulated as <jats:italic>trans</jats:italic>-[Pt (pic)<jats:sub>2</jats:sub>(acS)(D<jats:sub>2</jats:sub>O)]<jats:sup>+</jats:sup> (2), with the weaker peak one as <jats:italic>trans</jats:italic>-[Pt(pic)<jats:sub>2</jats:sub>(acS)<jats:sub>2</jats:sub>] (1). With GSH, the main product observed was <jats:italic>trans</jats:italic>-[Pt(pic)<jats:sub>2</jats:sub>(GS)<jats:sub>2</jats:sub>] (4), while the intermediate product was not observed during this study. In the reactions of <jats:italic>trans</jats:italic>-[PtCl<jats:sub>2</jats:sub>(pic)<jats:sub>2</jats:sub>] with acSH, besides complexes 1 and 3 formed, the formation of <jats:italic>trans</jats:italic>-[Pt(pic)<jats:sub>2</jats:sub>Cl(acS)] (6) was also observed in the NMR spectra, while when it was reacted with GSH, followed a similar course to that of with acSH, but more slowly.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"20 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141514692","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}
Thien Vuong Nguyen, Truc Vy Do, Thu Ha Hoang, Tuan Anh Nguyen, Le Trong Lu, Thi Mat Le, Thanh Minh Pham, Raa Khimi Shuib, Dai Lam Tran
The purpose of this work is to fabricate the advanced organic antibacterial coating containing the strong photocatalytic nanomaterials. For this purpose, firstly the TiO2–Ag hybrid nanoparticles are synthesized by chemical reduction method. Then, the antibacterial coating based on acrylic polyol, polyisocyanate, and these TiO2–Ag hybrid nanoparticles has been prepared. Mechanical properties show that the optimal content of TiO2–Ag hybrid nanoparticles in the coating matrix is 2 wt%, with its abrasion resistance of 166.2 L/mil; impact strength of 195 kg cm; adhesion of size #1 and relative hardness of 0.78. In addition, FE-SEM analysis shows that the nanocomposite coating has a tight structure with homogeneous dispersion of TiO2–Ag nanoparticles in the polymer matrix. The paint film has good antibacterial activity and has great application prospects. Data from the antibacterial test indicates that in the presence of an acrylic polyurethane coating containing 2 wt% TiO2–Ag, the number of viable Escherichia coli decreased from 3.4 × 105 CFU/ml to 1.5 × 102 CFU/ml after 24 h of culture.
{"title":"An antimicrobial acrylic polyurethane coating with TiO2-Ag hybrid nanoparticles","authors":"Thien Vuong Nguyen, Truc Vy Do, Thu Ha Hoang, Tuan Anh Nguyen, Le Trong Lu, Thi Mat Le, Thanh Minh Pham, Raa Khimi Shuib, Dai Lam Tran","doi":"10.1515/pac-2024-0019","DOIUrl":"https://doi.org/10.1515/pac-2024-0019","url":null,"abstract":"The purpose of this work is to fabricate the advanced organic antibacterial coating containing the strong photocatalytic nanomaterials. For this purpose, firstly the TiO<jats:sub>2</jats:sub>–Ag hybrid nanoparticles are synthesized by chemical reduction method. Then, the antibacterial coating based on acrylic polyol, polyisocyanate, and these TiO<jats:sub>2</jats:sub>–Ag hybrid nanoparticles has been prepared. Mechanical properties show that the optimal content of TiO<jats:sub>2</jats:sub>–Ag hybrid nanoparticles in the coating matrix is 2 wt%, with its abrasion resistance of 166.2 L/mil; impact strength of 195 kg cm; adhesion of size #1 and relative hardness of 0.78. In addition, FE-SEM analysis shows that the nanocomposite coating has a tight structure with homogeneous dispersion of TiO<jats:sub>2</jats:sub>–Ag nanoparticles in the polymer matrix. The paint film has good antibacterial activity and has great application prospects. Data from the antibacterial test indicates that in the presence of an acrylic polyurethane coating containing 2 wt% TiO<jats:sub>2</jats:sub>–Ag, the number of viable <jats:italic>Escherichia coli</jats:italic> decreased from 3.4 × 10<jats:sup>5</jats:sup> CFU/ml to 1.5 × 10<jats:sup>2</jats:sup> CFU/ml after 24 h of culture.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"331 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141196636","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}
Regarding economic significance, the Dioscoreaceae family, which includes the well-known Dioscorea (yam) species, is the fourth most important tuber crop globally. A basic meal found all across the world, yams encourage and ensure the food security of households. Although they are challenging to preserve and store however a post-harvest deterioration control must be developed. Over the years, Nigerian farmers have employed medicinal herbs to manage post-harvest pest invasion; nevertheless, the scientific basis for this fungal management has not yet been well documented. As a result, Landolphia owarensis leaf extract was used as a biological control, and fungi were isolated from Dioscorea cayenensis, Dioscorea alata, and Discorea rotundata. Samples of yam tubers – both rotten and healthy – were procured in the markets and brought to the lab for fungus isolation and identification. Leaves of Landolphia oweriensis were collected, air-dried, milled, and macerated in pure methanol for 72 h, extracted and concentrated with a rotary evaporator. The agar-well diffusion method was used for the biological control assay against the fungal isolates. The biological control results were presented as mean ± SD (standard deviation) while analysis of variance (Anova) was used to deduce least significant difference (LSD). A total number of 605 fungi isolates were observed in which D. cayenensis had the highest, 50.58 %, D. alata and Discorea rotundata 24.71 % respectively. Aspergillus niger and Aspergillus fumigatus were found in the three species while Aspergillus flavus, Rhizopus stolonifer, Collentotricum spp. and Penicillium spp. in either of the species. L. owarensis methanolic leaves extracts possesses biological potentials against Colletotrium spp., A. fumigatus, A. niger and A. flavus only. The problem of postharvest fungal invasion of Dioscorea species can be solved with the inhibition observed with L. owarensis methanolic leaves extracts as a biological control measure thereby sustaining food security in the world.
{"title":"Biological potentials of Landolphia owariensis leaf methanolic extract against pathogenic fungi isolates from different Dioscorea species","authors":"Olaitan C. Okechukwu, Enitan O. Adesanya","doi":"10.1515/pac-2023-1129","DOIUrl":"https://doi.org/10.1515/pac-2023-1129","url":null,"abstract":"Regarding economic significance, the Dioscoreaceae family, which includes the well-known Dioscorea (yam) species, is the fourth most important tuber crop globally. A basic meal found all across the world, yams encourage and ensure the food security of households. Although they are challenging to preserve and store however a post-harvest deterioration control must be developed. Over the years, Nigerian farmers have employed medicinal herbs to manage post-harvest pest invasion; nevertheless, the scientific basis for this fungal management has not yet been well documented. As a result, <jats:italic>Landolphia owarensis</jats:italic> leaf extract was used as a biological control, and fungi were isolated from <jats:italic>Dioscorea cayenensis</jats:italic>, <jats:italic>Dioscorea alata</jats:italic>, and <jats:italic>Discorea rotundata</jats:italic>. Samples of yam tubers – both rotten and healthy – were procured in the markets and brought to the lab for fungus isolation and identification. Leaves of <jats:italic>Landolphia oweriensis</jats:italic> were collected, air-dried, milled, and macerated in pure methanol for 72 h, extracted and concentrated with a rotary evaporator. The agar-well diffusion method was used for the biological control assay against the fungal isolates. The biological control results were presented as mean ± SD (standard deviation) while analysis of variance (Anova) was used to deduce least significant difference (LSD). A total number of 605 fungi isolates were observed in which <jats:italic>D</jats:italic>. <jats:italic>cayenensis</jats:italic> had the highest, 50.58 %, <jats:italic>D. alata</jats:italic> and <jats:italic>Discorea rotundata</jats:italic> 24.71 % respectively. <jats:italic>Aspergillus niger</jats:italic> and <jats:italic>Aspergillus fumigatus</jats:italic> were found in the three species while <jats:italic>Aspergillus flavus</jats:italic>, <jats:italic>Rhizopus stolonifer</jats:italic>, <jats:italic>Collentotricum spp</jats:italic>. and <jats:italic>Penicillium spp</jats:italic>. in either of the species. <jats:italic>L. owarensis</jats:italic> methanolic leaves extracts possesses biological potentials against <jats:italic>Colletotrium spp., A. fumigatus</jats:italic>, <jats:italic>A. niger</jats:italic> and <jats:italic>A. flavus</jats:italic> only. The problem of postharvest fungal invasion of <jats:italic>Dioscorea</jats:italic> species can be solved with the inhibition observed with <jats:italic>L. owarensis</jats:italic> methanolic leaves extracts as a biological control measure thereby sustaining food security in the world.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"21 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141169579","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}
Tuan Anh Nguyen, Thu Ha Hoang, Truc Vy Do, Thien Vuong Nguyen, Thi My Hanh Trinh, Minh Nguyet Ha, Khanh Linh Duong, Le Trong Lu, Raa Khimi Shuib, Dai Lam Tran
This work aims to fabricate the antibacterial coating with green biocide successfully. For this purpose, mimosa tannins were acylated with lauroyl chloride’s aid and pyridine’s support as a catalyst in the 1,4-dioxane, hexane and xylene solvents. Infrared analysis showed that mimosa tannins synthesized in the 1,4-dioxane were acylated better than in the other two solvents. FE-SEM analysis of the paint film showed that the acylated mimosa tannins at a content of 5 % dispersed quite well in the polymer matrix. The results of analyzing the mechanical properties of the paint film containing acylated mimosa tannins with contents ≤5 % show that the mechanical properties of the paint film are only slightly reduced compared to the mechanical properties of the pure coating, reaching the values: adhesion of size #1; abrasion resistance of 132.8 L/mil; impact strength of 170 kg cm and a relative hardness of 0.78. Antibacterial testing shows that the paint film containing 5 wt% acylated mimosa tannins have good antibacterial activity.
{"title":"Producing an antibacterial acrylic polyurethane coating with acylated mimosa tannins","authors":"Tuan Anh Nguyen, Thu Ha Hoang, Truc Vy Do, Thien Vuong Nguyen, Thi My Hanh Trinh, Minh Nguyet Ha, Khanh Linh Duong, Le Trong Lu, Raa Khimi Shuib, Dai Lam Tran","doi":"10.1515/pac-2024-0018","DOIUrl":"https://doi.org/10.1515/pac-2024-0018","url":null,"abstract":"This work aims to fabricate the antibacterial coating with green biocide successfully. For this purpose, mimosa tannins were acylated with lauroyl chloride’s aid and pyridine’s support as a catalyst in the 1,4-dioxane, hexane and xylene solvents. Infrared analysis showed that mimosa tannins synthesized in the 1,4-dioxane were acylated better than in the other two solvents. FE-SEM analysis of the paint film showed that the acylated mimosa tannins at a content of 5 % dispersed quite well in the polymer matrix. The results of analyzing the mechanical properties of the paint film containing acylated mimosa tannins with contents ≤5 % show that the mechanical properties of the paint film are only slightly reduced compared to the mechanical properties of the pure coating, reaching the values: adhesion of size #1; abrasion resistance of 132.8 L/mil; impact strength of 170 kg cm and a relative hardness of 0.78. Antibacterial testing shows that the paint film containing 5 wt% acylated mimosa tannins have good antibacterial activity.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"43 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141169858","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}
Mycotoxins are common contaminants in food and feed in Africa, and their occurrence presents negative health and economic impacts. One step towards control is the adoption of highly efficient extraction methods for effective monitoring. QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) has gained popularity among researchers for multiple mycotoxin analyses. Various modifications of the original QuEChERS method have emerged as means to achieve maximum mycotoxin recoveries from different matrices, such as cereals, animal feed, nuts, edible oils, and spices. This review provides a summary of the occurrence of multiple mycotoxins in Africa as well as a summary of the QuEChERS modifications done to increase the extraction of mycotoxins from food and feed samples.
{"title":"Current advances in QuEChERS extraction of mycotoxins in various food and feed matrices","authors":"Mesha Mbisana, Dikabo Mogopodi, Inonge Chibua","doi":"10.1515/pac-2023-1133","DOIUrl":"https://doi.org/10.1515/pac-2023-1133","url":null,"abstract":"Mycotoxins are common contaminants in food and feed in Africa, and their occurrence presents negative health and economic impacts. One step towards control is the adoption of highly efficient extraction methods for effective monitoring. QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) has gained popularity among researchers for multiple mycotoxin analyses. Various modifications of the original QuEChERS method have emerged as means to achieve maximum mycotoxin recoveries from different matrices, such as cereals, animal feed, nuts, edible oils, and spices. This review provides a summary of the occurrence of multiple mycotoxins in Africa as well as a summary of the QuEChERS modifications done to increase the extraction of mycotoxins from food and feed samples.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"18 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141169613","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}
Subhasri Bogadi, Pooja Rao, Vasudha KU, Gowthamarajan Kuppusamy, SubbaRao V. Madhunapantula, Vetriselvan Subramaniyan, Veera Venkata Satyanarayana Reddy Karri, Jamuna Bai Aswathanarayan
Biofilms are complex bacterial colonies embedded in an extracellular matrix. These pose a major obstacle to wound healing and are noticeable in chronic wounds. It protects the bacteria from the host’s immune system and conventional antibiotic treatments. The biofilm’s protective matrix prevents essential nutrients and oxygen from diffusing into the surrounding healthy tissue. In addition, microbes living in biofilms naturally have increased resistance to antibiotics, which reduces the effectiveness of traditional therapies. As such, biofilms serve as persistent reservoirs of infection, which further disrupts the normal course of wound healing. In this review, the current formulation strategies such as hydrogels, polymeric nanoparticles, and nanofibers that are used in wound healing to counteract biofilms have been comprehensively discussed. The formulations have been meticulously designed and developed to disturb the biofilm matrix, prevent the growth of microorganisms, and increase the potency of antimicrobials and antibiotics. The mechanism of action, advantages and limitations associated with the existing formulation strategies have been reviewed. The formulation strategies that have been translated into clinical applications and patented are also discussed in this paper.
{"title":"Management of biofilm-associated infections in diabetic wounds – from bench to bedside","authors":"Subhasri Bogadi, Pooja Rao, Vasudha KU, Gowthamarajan Kuppusamy, SubbaRao V. Madhunapantula, Vetriselvan Subramaniyan, Veera Venkata Satyanarayana Reddy Karri, Jamuna Bai Aswathanarayan","doi":"10.1515/pac-2023-1117","DOIUrl":"https://doi.org/10.1515/pac-2023-1117","url":null,"abstract":"Biofilms are complex bacterial colonies embedded in an extracellular matrix. These pose a major obstacle to wound healing and are noticeable in chronic wounds. It protects the bacteria from the host’s immune system and conventional antibiotic treatments. The biofilm’s protective matrix prevents essential nutrients and oxygen from diffusing into the surrounding healthy tissue. In addition, microbes living in biofilms naturally have increased resistance to antibiotics, which reduces the effectiveness of traditional therapies. As such, biofilms serve as persistent reservoirs of infection, which further disrupts the normal course of wound healing. In this review, the current formulation strategies such as hydrogels, polymeric nanoparticles, and nanofibers that are used in wound healing to counteract biofilms have been comprehensively discussed. The formulations have been meticulously designed and developed to disturb the biofilm matrix, prevent the growth of microorganisms, and increase the potency of antimicrobials and antibiotics. The mechanism of action, advantages and limitations associated with the existing formulation strategies have been reviewed. The formulation strategies that have been translated into clinical applications and patented are also discussed in this paper.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"156 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930589","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}
Anastasia I. Ioannou, Demetris E. Apostolides, Costas S. Patrickios
Five randomly cross-linked amphiphilic copolymer networks (ACPN) were prepared via the free radical cross-linking copolymerization of the hydrophobic <jats:italic>n</jats:italic>-butyl acrylate (BuA) and the hydrophilic <jats:italic>N</jats:italic>,<jats:italic>N</jats:italic>-dimethylacrylamide (DMAAm), in the presence of a small amount (5 mol% with respect to the sum of BuA plus DMAAm monomers) of the hydrophobic 1,6-hexanediol diacrylate (HexDA) cross-linker, initiated by 4,4ʹ-azobis(4-cyanovaleric acid) in 1,4-dioxane at a 10 % w/v total monomer concentration. The five ACPNs differed in their BuA content, fixed at 10, 30, 50, 70 and 90 mol%. The two homopolymer networks, BuA and DMAAm, were also prepared using the same polymerization method. Thus, this study involved a total of seven polymer networks, forming a homologous series with BuA contents ranging from 0 to 100 mol%. These networks were characterized in terms of their degrees of swelling in tetrahydrofuran (THF) and water, their mechanical properties in water, and their adhesion to human skin. The degrees of swelling (DS) of the networks in THF were higher than those in water because THF is a non-selective solvent, whereas water is selective for the hydrophilic DMAAm units. The DSs in THF increased with the network content in the less polar BuA units, while the opposite was true for the DSs in water which decreased with the content in the hydrophobic BuA units from 11 (0 mol% BuA) down to 1.1 (100 mol% BuA). A maximum in the elastic modulus was observed for the hydrogel with 50 mol% BuA, reflecting the opposing effects of polymer composition in soft polymer (polyBuA) content and hydrogel water content. In contrast, the tensile strain at break increased monotonically with the hydrogel BuA content, reaching a remarkable ∼900 % for the hydrogel with 90 mol% BuA. Finally, the adhesion of the ACPNs, both in their dried and hydrated states, onto human skin was explored. The adhesion of the hydrated samples onto skin was stronger than that of the dried ones. The hydrated ACPN with 30 mol% BuA exhibited the strongest adhesion onto skin, attributable to the best combination of a rather high content in polar DMAAm units (70 mol%), and a rather low aqueous DS (∼2.5), with the low DS value causing only a small dilution in the DMAAm units participating in the polar interactions with skin. The present work demonstrates that, even in this synthetically simple ACPN system, the multiple effects of ACPN composition on a certain property, in some cases opposing and in some other cooperating, lead to a rather complicated behavior. In particular, as the BuA content increases, some properties display maxima (elastic modulus, stress at break and fracture energy of hydrated ACPNs, and adhesion of hydrated ACPNs onto skin) while some other properties exhibit monotonic increases (strain at break of hydrated ACPNs, and adhesion of dried ACPNs onto skin). Thus, the optimal ACPN for a particular application will h
{"title":"Randomly cross-linked amphiphilic copolymer networks of n-butyl acrylate and N,N-dimethylacrylamide: synthesis and characterization","authors":"Anastasia I. Ioannou, Demetris E. Apostolides, Costas S. Patrickios","doi":"10.1515/pac-2024-0201","DOIUrl":"https://doi.org/10.1515/pac-2024-0201","url":null,"abstract":"Five randomly cross-linked amphiphilic copolymer networks (ACPN) were prepared via the free radical cross-linking copolymerization of the hydrophobic <jats:italic>n</jats:italic>-butyl acrylate (BuA) and the hydrophilic <jats:italic>N</jats:italic>,<jats:italic>N</jats:italic>-dimethylacrylamide (DMAAm), in the presence of a small amount (5 mol% with respect to the sum of BuA plus DMAAm monomers) of the hydrophobic 1,6-hexanediol diacrylate (HexDA) cross-linker, initiated by 4,4ʹ-azobis(4-cyanovaleric acid) in 1,4-dioxane at a 10 % w/v total monomer concentration. The five ACPNs differed in their BuA content, fixed at 10, 30, 50, 70 and 90 mol%. The two homopolymer networks, BuA and DMAAm, were also prepared using the same polymerization method. Thus, this study involved a total of seven polymer networks, forming a homologous series with BuA contents ranging from 0 to 100 mol%. These networks were characterized in terms of their degrees of swelling in tetrahydrofuran (THF) and water, their mechanical properties in water, and their adhesion to human skin. The degrees of swelling (DS) of the networks in THF were higher than those in water because THF is a non-selective solvent, whereas water is selective for the hydrophilic DMAAm units. The DSs in THF increased with the network content in the less polar BuA units, while the opposite was true for the DSs in water which decreased with the content in the hydrophobic BuA units from 11 (0 mol% BuA) down to 1.1 (100 mol% BuA). A maximum in the elastic modulus was observed for the hydrogel with 50 mol% BuA, reflecting the opposing effects of polymer composition in soft polymer (polyBuA) content and hydrogel water content. In contrast, the tensile strain at break increased monotonically with the hydrogel BuA content, reaching a remarkable ∼900 % for the hydrogel with 90 mol% BuA. Finally, the adhesion of the ACPNs, both in their dried and hydrated states, onto human skin was explored. The adhesion of the hydrated samples onto skin was stronger than that of the dried ones. The hydrated ACPN with 30 mol% BuA exhibited the strongest adhesion onto skin, attributable to the best combination of a rather high content in polar DMAAm units (70 mol%), and a rather low aqueous DS (∼2.5), with the low DS value causing only a small dilution in the DMAAm units participating in the polar interactions with skin. The present work demonstrates that, even in this synthetically simple ACPN system, the multiple effects of ACPN composition on a certain property, in some cases opposing and in some other cooperating, lead to a rather complicated behavior. In particular, as the BuA content increases, some properties display maxima (elastic modulus, stress at break and fracture energy of hydrated ACPNs, and adhesion of hydrated ACPNs onto skin) while some other properties exhibit monotonic increases (strain at break of hydrated ACPNs, and adhesion of dried ACPNs onto skin). Thus, the optimal ACPN for a particular application will h","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"129 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930612","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 present study investigates the electrochemistry spectroscopy of Sm(III), and electrodeposition of samarium metal in neutral ligand-based ionic liquid (solvate ionic liquid). Mixture consisted of a samarium precursor (either samarium triflate or samarium nitrate hexahydrate) in the solvate ionic liquid, 1.3-dimethyl-2-imidazolidone (DMI). FT-IR analysis of Sm(III)-DMI electrolytes indicates that Sm3+ ion coordinates with DMI through carbonyl group (C=O); the band splits into two with emergence of new peak at 1630 cm−1 and 1649 cm−1 for the triflate and nitrate solutions, respectively. Raman spectroscopy also confirms the solvation of Sm(III) with DMI through oxygen atom of the carbonyl group. Voltametric behaviour of Sm(III) ion indicates two-step reduction mechanism via Sm(III)/Sm(II) at ca. −2.0 V and Sm(II)/Sm(0) at ca. −3.0 V vs. Ag/Ag+ for both samarium(III)-containing electrolytes. Diffusion coefficient value of Sm(III) was determined to be 2.185 × 10−6 cm2/s and 2.418 × 10−8 cm2/s for triflate and nitrate electrolytes, respectively. Electrodeposition of samarium was achieved through constant potential electrolysis using copper substrate as the working electrode which yielded compact deposits from triflate-DMI and non-uniform granular deposit from nitrate-DMI electrolyte. Ex situ X-ray photoelectron spectroscopy analysis of the as-deposited samples revealed the presence of metallic Sm (1081 eV) co-existing with its oxide form (1083 eV).
{"title":"Electrodeposition behaviour of samarium in 1,3-dimethyl-2-imidazolidone solvent","authors":"Chrysanthus Andrew, Jayakumar Mani","doi":"10.1515/pac-2024-0110","DOIUrl":"https://doi.org/10.1515/pac-2024-0110","url":null,"abstract":"The present study investigates the electrochemistry spectroscopy of Sm(III), and electrodeposition of samarium metal in neutral ligand-based ionic liquid (solvate ionic liquid). Mixture consisted of a samarium precursor (either samarium triflate or samarium nitrate hexahydrate) in the solvate ionic liquid, 1.3-dimethyl-2-imidazolidone (DMI). FT-IR analysis of Sm(III)-DMI electrolytes indicates that Sm<jats:sup>3+</jats:sup> ion coordinates with DMI through carbonyl group (C=O); the band splits into two with emergence of new peak at 1630 cm<jats:sup>−1</jats:sup> and 1649 cm<jats:sup>−1</jats:sup> for the triflate and nitrate solutions, respectively. Raman spectroscopy also confirms the solvation of Sm(III) with DMI through oxygen atom of the carbonyl group. Voltametric behaviour of Sm(III) ion indicates two-step reduction mechanism <jats:italic>via</jats:italic> Sm(III)/Sm(II) at <jats:italic>ca.</jats:italic> −2.0 V and Sm(II)/Sm(0) at <jats:italic>ca.</jats:italic> −3.0 V vs. Ag/Ag<jats:sup>+</jats:sup> for both samarium(III)-containing electrolytes. Diffusion coefficient value of Sm(III) was determined to be 2.185 × 10<jats:sup>−6</jats:sup> cm<jats:sup>2</jats:sup>/s and 2.418 × 10<jats:sup>−8</jats:sup> cm<jats:sup>2</jats:sup>/s for triflate and nitrate electrolytes, respectively. Electrodeposition of samarium was achieved through constant potential electrolysis using copper substrate as the working electrode which yielded compact deposits from triflate-DMI and non-uniform granular deposit from nitrate-DMI electrolyte. <jats:italic>Ex situ</jats:italic> X-ray photoelectron spectroscopy analysis of the as-deposited samples revealed the presence of metallic Sm (1081 eV) co-existing with its oxide form (1083 eV).","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930591","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}
Yetunde Bunmi Oyeyiola, Francis Bayo Lewu, Beatrice Olutoyin Opeolu
Nitrogenous fertilizer drift from farmlands accelerates nitrogen loads in groundwaters. Biochar potential to mitigate nitrogen leaching in urea treated sandy soil was monitored in a four weeks screenhouse leaching column experiment. The trial was a factorial combination of two biochar types (B1 and B2 applied at 5 t/ha) and two urea treatments (with urea at 120 kg/ha and without urea) laid in completely randomized design with three replications. Control that received neither urea nor biochar was compared. Four weekly leaching events were conducted in each leaching column containing 300 g soil amended with appropriate treatments. Amaranthus hybridus was the test crop. The NH4-N and NO3-N leached were generally highest during the week 2 leaching event such that total NO3-N leached was 427.3 % higher than total NH4-N leached with highest contributions from sole urea treatment. Biochar pretreatment reduced total N leached by 9.5 (B1) and 26.8 % (B2) relative to sole urea. Percentage of N added lost to leaching was highest (34.1 %) in sole urea treatment with B1 and B2 pretreatment reducing the value by 54.5 and 46.9 % respectively. Correlation analysis revealed electrical conductivity of the leachate and soil as dominant indicators for N leached in the soil studied.
{"title":"Nitrogen leaching mitigation by tithonia biochar (Tithochar) in urea fertilizer treated sandy soil","authors":"Yetunde Bunmi Oyeyiola, Francis Bayo Lewu, Beatrice Olutoyin Opeolu","doi":"10.1515/pac-2023-1137","DOIUrl":"https://doi.org/10.1515/pac-2023-1137","url":null,"abstract":"Nitrogenous fertilizer drift from farmlands accelerates nitrogen loads in groundwaters. Biochar potential to mitigate nitrogen leaching in urea treated sandy soil was monitored in a four weeks screenhouse leaching column experiment. The trial was a factorial combination of two biochar types (B1 and B2 applied at 5 t/ha) and two urea treatments (with urea at 120 kg/ha and without urea) laid in completely randomized design with three replications. Control that received neither urea nor biochar was compared. Four weekly leaching events were conducted in each leaching column containing 300 g soil amended with appropriate treatments. <jats:italic>Amaranthus hybridus</jats:italic> was the test crop. The NH<jats:sub>4</jats:sub>-N and NO<jats:sub>3</jats:sub>-N leached were generally highest during the week 2 leaching event such that total NO<jats:sub>3</jats:sub>-N leached was 427.3 % higher than total NH<jats:sub>4</jats:sub>-N leached with highest contributions from sole urea treatment. Biochar pretreatment reduced total N leached by 9.5 (B1) and 26.8 % (B2) relative to sole urea. Percentage of N added lost to leaching was highest (34.1 %) in sole urea treatment with B1 and B2 pretreatment reducing the value by 54.5 and 46.9 % respectively. Correlation analysis revealed electrical conductivity of the leachate and soil as dominant indicators for N leached in the soil studied.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"22 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930709","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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