Abstract Osteoarthritis (OA) is a common degenerative disease that develops over time, characterized mainly by inflammatory joints, cartilage deterioration, and ultimately loss of normal joint function. Some of the limitations that restrict the effectiveness of current OA treatment procedures include minimal penetration of medications into cartilage and lack of vascularity, leading to insufficient bioavailability and systemic toxicity. To increase the effectiveness of treatment, it is necessary to create novel non‐invasive OA treatment techniques. Porous nanomaterials (PNMs) show great promise as sustained drug delivery systems (DDSs) due to their functionality, variable porosity, and high loading capacity. In addition, they can provide targeted drug delivery, facilitate controlled release of drugs, and prolong drug circulation and retention time while reducing adverse reactions and improving drug solubility. First, the current treatment methods and challenges are summarized. Subsequently, recent advances in DDSs for OA treatment based on PNMs with various pore sizes and structures are presented. Lastly, the parameters that affect the performance of DDSs are discussed by giving some suggestions for their design. The purpose of this review is to provide new insights into PNM‐based DDS design and to inspire readers to adopt the smart design of intra‐articular DDSs in the future.
{"title":"Recent advances in porous nanomaterials‐based drug delivery systems for osteoarthritis","authors":"Senem Çitoğlu, Hatice Duran","doi":"10.1002/nano.202300099","DOIUrl":"https://doi.org/10.1002/nano.202300099","url":null,"abstract":"Abstract Osteoarthritis (OA) is a common degenerative disease that develops over time, characterized mainly by inflammatory joints, cartilage deterioration, and ultimately loss of normal joint function. Some of the limitations that restrict the effectiveness of current OA treatment procedures include minimal penetration of medications into cartilage and lack of vascularity, leading to insufficient bioavailability and systemic toxicity. To increase the effectiveness of treatment, it is necessary to create novel non‐invasive OA treatment techniques. Porous nanomaterials (PNMs) show great promise as sustained drug delivery systems (DDSs) due to their functionality, variable porosity, and high loading capacity. In addition, they can provide targeted drug delivery, facilitate controlled release of drugs, and prolong drug circulation and retention time while reducing adverse reactions and improving drug solubility. First, the current treatment methods and challenges are summarized. Subsequently, recent advances in DDSs for OA treatment based on PNMs with various pore sizes and structures are presented. Lastly, the parameters that affect the performance of DDSs are discussed by giving some suggestions for their design. The purpose of this review is to provide new insights into PNM‐based DDS design and to inspire readers to adopt the smart design of intra‐articular DDSs in the future.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"133 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136351831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hanna Sopha, Mahnaz Alijani, Marcela Sepúlveda, Jan M. Macak
Abstract Self‐organized anodic TiO 2 nanotube (TNT) layers prepared by anodization of Ti substrates have attracted great interest within the last 20 years, due to their unique properties and low‐cost synthesis. This mini review article aims to shortly summarize the most recent developments in the TNT layer synthesis and applications. It presents the synthesis of high aspect ratio (HAR) TNT layers in a short time by accelerating the TNT layer growth rates in lactic acid containing electrolytes. Furthermore, the etching of TNT layers towards TNT bundles of homogeneous size and single tube powders is discussed, as well as the possibility to grow TNT layers on non‐planar Ti substrates, which cannot be directly connected to the potentiostat (e.g., Ti spheres or 3D Ti meshes). As a relatively new application, the employment of TNT layers in microwave resonator sensors is introduced. Last, but not least, approaches of upscaling the TNT layer size from the laboratory scale towards significantly larger scale are outlined and reviewed.
{"title":"Recent advances in TiO<sub>2</sub> nanotube layers – A mini review of the latest developments in nanotube preparation and applications in photocatalysis and microwave sensing","authors":"Hanna Sopha, Mahnaz Alijani, Marcela Sepúlveda, Jan M. Macak","doi":"10.1002/nano.202300140","DOIUrl":"https://doi.org/10.1002/nano.202300140","url":null,"abstract":"Abstract Self‐organized anodic TiO 2 nanotube (TNT) layers prepared by anodization of Ti substrates have attracted great interest within the last 20 years, due to their unique properties and low‐cost synthesis. This mini review article aims to shortly summarize the most recent developments in the TNT layer synthesis and applications. It presents the synthesis of high aspect ratio (HAR) TNT layers in a short time by accelerating the TNT layer growth rates in lactic acid containing electrolytes. Furthermore, the etching of TNT layers towards TNT bundles of homogeneous size and single tube powders is discussed, as well as the possibility to grow TNT layers on non‐planar Ti substrates, which cannot be directly connected to the potentiostat (e.g., Ti spheres or 3D Ti meshes). As a relatively new application, the employment of TNT layers in microwave resonator sensors is introduced. Last, but not least, approaches of upscaling the TNT layer size from the laboratory scale towards significantly larger scale are outlined and reviewed.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"18 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135393073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nazia Tabassum, David Rudd, Li Yan, Nicolas H. Voelcker, Maria Alba
Abstract There is a global trend of increasing antibiotic resistance to Gram‐negative bacteria and the medical research community is looking for alternative antibiotics. Antibiotics such as polymyxin B (PMB) show excellent efficacy and low resistance rates against Gram‐negative bacteria. The topical administration of PMB, however, has clinical limitations such as minimal residence time, making it difficult for its use to treat skin infections. Here, we present porous silicon microneedle (pSi MN) patches to deliver PMB to the skin. pSi MN patches are fabricated by, first, generating the projections by dry Si etching techniques, followed by an electrochemical etching to create porous layers around the MNs. After loading PMB into the porous layer, the antibacterial activity of pSi MNs is determined by measuring the inhibition zone of Gram‐negative Escherichia coli . Next, PMB is efficiently delivered into the epidermal layer of ex vivo skin models, as confirmed by chemical mapping using matrix‐assisted laser desorption/ionization mass spectrometry imaging (MALDI‐MSI). The results demonstrate that pSi MN patches are an efficient and versatile tool for the transdermal delivery of PMB with maintained bioactivity and antimicrobial efficacy, thus expanding the possibilities of current transdermal drug delivery systems.
{"title":"Porous silicon microneedle patches for delivery of polymyxin‐based antimicrobials","authors":"Nazia Tabassum, David Rudd, Li Yan, Nicolas H. Voelcker, Maria Alba","doi":"10.1002/nano.202300116","DOIUrl":"https://doi.org/10.1002/nano.202300116","url":null,"abstract":"Abstract There is a global trend of increasing antibiotic resistance to Gram‐negative bacteria and the medical research community is looking for alternative antibiotics. Antibiotics such as polymyxin B (PMB) show excellent efficacy and low resistance rates against Gram‐negative bacteria. The topical administration of PMB, however, has clinical limitations such as minimal residence time, making it difficult for its use to treat skin infections. Here, we present porous silicon microneedle (pSi MN) patches to deliver PMB to the skin. pSi MN patches are fabricated by, first, generating the projections by dry Si etching techniques, followed by an electrochemical etching to create porous layers around the MNs. After loading PMB into the porous layer, the antibacterial activity of pSi MNs is determined by measuring the inhibition zone of Gram‐negative Escherichia coli . Next, PMB is efficiently delivered into the epidermal layer of ex vivo skin models, as confirmed by chemical mapping using matrix‐assisted laser desorption/ionization mass spectrometry imaging (MALDI‐MSI). The results demonstrate that pSi MN patches are an efficient and versatile tool for the transdermal delivery of PMB with maintained bioactivity and antimicrobial efficacy, thus expanding the possibilities of current transdermal drug delivery systems.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"80 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135432691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This investigation emphasizes the study of the structural, mechanical, thermophysical, thermodynamical, and optoelectronic properties of a Dion‐Jacobson Perovskite‐like Layered Structured (PLS) CsLaNb 2 O 7 using the first‐principles. The former experimental investigation accepts the estimated lattice parameters and unit cell volume at the ground state. The material is mechanically stable, ductile, and anisotropic in nature. The phonon dispersion characteristics, phonon density of states, zero‐point energy and temperature‐dependent‐ enthalpy, entropy, and Debye temperature have been studied for the first time. The band gap is found to be direct. Different orbital contributions in electronic bonding have been visualized in the PDOS diagram. Optical anisotropic properties have also been investigated along the [100] and [001] polarizing directions. This material shows promising properties in the fabrication of multifunctional materials.
{"title":"First‐principles investigations of the Dion‐Jacobson PLS CsLaNb<sub>2</sub>O<sub>7</sub>: An outstanding multifunctional material for green technology","authors":"Mehedi Hasan, A. K. M. Akther Hossain","doi":"10.1002/nano.202300095","DOIUrl":"https://doi.org/10.1002/nano.202300095","url":null,"abstract":"Abstract This investigation emphasizes the study of the structural, mechanical, thermophysical, thermodynamical, and optoelectronic properties of a Dion‐Jacobson Perovskite‐like Layered Structured (PLS) CsLaNb 2 O 7 using the first‐principles. The former experimental investigation accepts the estimated lattice parameters and unit cell volume at the ground state. The material is mechanically stable, ductile, and anisotropic in nature. The phonon dispersion characteristics, phonon density of states, zero‐point energy and temperature‐dependent‐ enthalpy, entropy, and Debye temperature have been studied for the first time. The band gap is found to be direct. Different orbital contributions in electronic bonding have been visualized in the PDOS diagram. Optical anisotropic properties have also been investigated along the [100] and [001] polarizing directions. This material shows promising properties in the fabrication of multifunctional materials.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"18 24","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135819173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rafael Miguel Sábio, Gabriela Corrêa Carvalho, Jiachen Li, Marlus Chorilli, Hélder A. Santos
Infectious diseases are a global public health concern generated by uncontrolled uses of antimicrobials resulting in multidrug‐resistant (MDR) pathogens. The antimicrobial resistance (AMR) has made explicit the ineffective action of the current medicines and vaccines. Rapid diagnosis and effective treatment are the keys to reduce the capacity of MDR pathogens spreading very fast, avoiding high socioeconomic impact, severe and prolonged illness and death. Advanced porous materials have emerged as promising alternatives to the conventional diagnoses and therapy due to their low‐cost production, high biocompatibility, adjustable porous structure, large surface area, easy surface functionalization and capacity of loading high drugs amount. In this review, we first highlighted the current strategies to fight against infectious diseases. Then, we introduce the main advanced porous materials used in infectious diseases, including mesoporous silica nanoparticles (MSNs), porous silicon nanoparticles (PSiNPs), metal–organic frameworks (MOFs), covalent–organic frameworks (COFs), hydrogen‐bonded organic frameworks (HOFs) and porous carbon materials. The strategies to fabricate these materials and their characterization for the application in the recent years for antimicrobial treatment is also discussed. Finally, we present an overview outlook and challenges on the future application of such materials for infectious diseases.
{"title":"Advanced porous materials for antimicrobial treatment","authors":"Rafael Miguel Sábio, Gabriela Corrêa Carvalho, Jiachen Li, Marlus Chorilli, Hélder A. Santos","doi":"10.1002/nano.202300114","DOIUrl":"https://doi.org/10.1002/nano.202300114","url":null,"abstract":"Infectious diseases are a global public health concern generated by uncontrolled uses of antimicrobials resulting in multidrug‐resistant (MDR) pathogens. The antimicrobial resistance (AMR) has made explicit the ineffective action of the current medicines and vaccines. Rapid diagnosis and effective treatment are the keys to reduce the capacity of MDR pathogens spreading very fast, avoiding high socioeconomic impact, severe and prolonged illness and death. Advanced porous materials have emerged as promising alternatives to the conventional diagnoses and therapy due to their low‐cost production, high biocompatibility, adjustable porous structure, large surface area, easy surface functionalization and capacity of loading high drugs amount. In this review, we first highlighted the current strategies to fight against infectious diseases. Then, we introduce the main advanced porous materials used in infectious diseases, including mesoporous silica nanoparticles (MSNs), porous silicon nanoparticles (PSiNPs), metal–organic frameworks (MOFs), covalent–organic frameworks (COFs), hydrogen‐bonded organic frameworks (HOFs) and porous carbon materials. The strategies to fabricate these materials and their characterization for the application in the recent years for antimicrobial treatment is also discussed. Finally, we present an overview outlook and challenges on the future application of such materials for infectious diseases.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"212 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135869626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This study investigated the characterization, antifungal activity, and biocompatibility of green agar/silver and collagen/silver bionanocomposite films for wound healing and cell growth scaffolds. Silver nanoparticles (AgNPs) are known for their antimicrobial properties, but their toxicity and harsh synthesis limit their applications. To address this, green‐synthesized AgNPs G‐AgNPs were incorporated into agar/collagen suspensions at specific concentrations and three different G‐AgNP‐agar and two different G‐AgNP‐col bionanocomposite films were produced. Nanoparticle homogeneity and film quality were characterized through SEM analysis. Mechanical properties were tested using a uniaxial tensile tester, revealing that the bioplastic control samples exhibited UTS of 3.86 MPa compared to 0.60 MPa for collagen, a 6‐fold improvement. Viable cell metabolic activity derived from MTT assay showed that Col‐4%AgNPs and Bio‐30%AgNPs had a 42.9% and 51.6% increase in net metabolic activity respectively compared to control on day 4. Fluorescence microscopy confirmed enhanced cell adhesion and proliferation in G‐AgNP‐incorporated samples. Antifungal properties were evaluated against Cladosporium spores, able to cause severe diseases when in contact with human skins, following ISO 16869:2008 standards. The demonstrated unique properties and tunability of G‐AgNPs bionanocomposites can be employed in a variety of specialties for wound‐healing applications, to improve rate and quality of healing while reducing the risk of infection.
{"title":"In vitro characterization of bionanocomposites with green silver nanoparticles: A step towards sustainable wound healing materials","authors":"Federico Trotta, Alna Dony, Monica Mok, Alessandra Grillo, Thomas Whitehead‐Clarke, Shervanthi Homer‐Vanniasinkam, Alvena Kureshi","doi":"10.1002/nano.202300087","DOIUrl":"https://doi.org/10.1002/nano.202300087","url":null,"abstract":"Abstract This study investigated the characterization, antifungal activity, and biocompatibility of green agar/silver and collagen/silver bionanocomposite films for wound healing and cell growth scaffolds. Silver nanoparticles (AgNPs) are known for their antimicrobial properties, but their toxicity and harsh synthesis limit their applications. To address this, green‐synthesized AgNPs G‐AgNPs were incorporated into agar/collagen suspensions at specific concentrations and three different G‐AgNP‐agar and two different G‐AgNP‐col bionanocomposite films were produced. Nanoparticle homogeneity and film quality were characterized through SEM analysis. Mechanical properties were tested using a uniaxial tensile tester, revealing that the bioplastic control samples exhibited UTS of 3.86 MPa compared to 0.60 MPa for collagen, a 6‐fold improvement. Viable cell metabolic activity derived from MTT assay showed that Col‐4%AgNPs and Bio‐30%AgNPs had a 42.9% and 51.6% increase in net metabolic activity respectively compared to control on day 4. Fluorescence microscopy confirmed enhanced cell adhesion and proliferation in G‐AgNP‐incorporated samples. Antifungal properties were evaluated against Cladosporium spores, able to cause severe diseases when in contact with human skins, following ISO 16869:2008 standards. The demonstrated unique properties and tunability of G‐AgNPs bionanocomposites can be employed in a variety of specialties for wound‐healing applications, to improve rate and quality of healing while reducing the risk of infection.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135618871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diego Gomez‐Maldonado, Gabriel Au, Sarah Zohdy, Virginia A. Davis, Maria S. Peresin
Abstract Enhanced and rapid surveillance for diseases is critical to public health and meeting United Nations' Sustainable Development Goal for Good Health and Well‐being by allowing for targeted and accelerated prevention and control response strategies. Human malaria, caused by Plasmodium spp. and transmitted by mosquitoes is no exception. Advances in sustainable materials provide an opportunity to improve fast, sustainable, and equitable testing assays. Here, naturally abundant polymers and biomaterials, such as cellulose nanocrystals (CNCs) and chitosan, were used to increase antibody density deposition on the assay detection line when compared to traditional free antibody deposition, and thus the sensitivity, of easily assembled rapid tests designed to detect Plasmodium vivax infective (sporozoite) parasites in mosquitoes, a critical indicator of malaria transmission. The immobilization of antibodies onto chitosan‐coated CNCs allowed for antigen detection with a lower number of antibodies used in each test; likewise, the immobilization allowed to directly place the CNC‐Ab without the traditionally needed blockers layer on the paper like bovine serum albumin (BSA). This bio‐based prototype of a paper‐based dipstick assay shows a promising pathway for the development of rapid disease surveillance tools using sustainable and globally available materials.
{"title":"Rapid production of <i>Plasmodium</i> sporozoite detection paper dipstick assays using cellulose nanocrystals: Proof‐of‐concept for bio‐based, locally developed, point‐of‐care devices","authors":"Diego Gomez‐Maldonado, Gabriel Au, Sarah Zohdy, Virginia A. Davis, Maria S. Peresin","doi":"10.1002/nano.202300093","DOIUrl":"https://doi.org/10.1002/nano.202300093","url":null,"abstract":"Abstract Enhanced and rapid surveillance for diseases is critical to public health and meeting United Nations' Sustainable Development Goal for Good Health and Well‐being by allowing for targeted and accelerated prevention and control response strategies. Human malaria, caused by Plasmodium spp. and transmitted by mosquitoes is no exception. Advances in sustainable materials provide an opportunity to improve fast, sustainable, and equitable testing assays. Here, naturally abundant polymers and biomaterials, such as cellulose nanocrystals (CNCs) and chitosan, were used to increase antibody density deposition on the assay detection line when compared to traditional free antibody deposition, and thus the sensitivity, of easily assembled rapid tests designed to detect Plasmodium vivax infective (sporozoite) parasites in mosquitoes, a critical indicator of malaria transmission. The immobilization of antibodies onto chitosan‐coated CNCs allowed for antigen detection with a lower number of antibodies used in each test; likewise, the immobilization allowed to directly place the CNC‐Ab without the traditionally needed blockers layer on the paper like bovine serum albumin (BSA). This bio‐based prototype of a paper‐based dipstick assay shows a promising pathway for the development of rapid disease surveillance tools using sustainable and globally available materials.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135888818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ruth Fabiola Balderas Valadez, Augusto David Ariza Flores, Claudia Pacholski
Abstract Porous silicon 1D photonic crystals, namely rugate filters, are covered with a loosely packed hexagonally ordered array of stimuli‐responsive hydrogel microgels, and the optical properties of the resulting hybrid sensor are thoroughly investigated. For this purpose, both rugate filters with and without hydrogel microgel on top are immersed in ethanol/water mixtures possessing different compositions and NaCl solutions. Reflectance spectra of all samples are taken and analyzed concerning the spectral positions and reflectance intensity of the strong peak related to the photonic crystal rugate peak as well as the side bands resulting from Fabry–Pérot interference at the interfaces bordering the porous silicon. For the latter analysis, a Fourier transform is applied to the side bands for calculating the effective optical thickness (EOT). Thereby it can be shown that the spectral position of both the rugate peak and the EOT peak is best suited for monitoring refractive index changes in the immersion medium whereas the swelling and collapse of the stimuli‐responsive hydrogel microgel can be only detected by variations in the amplitude of the rugate peak and the EOT peak. These results are confirmed by simulations using a simple geometrical model and shall serve as guide for developing tailor‐made optical sensors.
{"title":"Stimuli‐responsive hydrogel microgels on porous silicon one‐dimensional photonic crystals: Tapping the full potential for optical sensor applications","authors":"Ruth Fabiola Balderas Valadez, Augusto David Ariza Flores, Claudia Pacholski","doi":"10.1002/nano.202300100","DOIUrl":"https://doi.org/10.1002/nano.202300100","url":null,"abstract":"Abstract Porous silicon 1D photonic crystals, namely rugate filters, are covered with a loosely packed hexagonally ordered array of stimuli‐responsive hydrogel microgels, and the optical properties of the resulting hybrid sensor are thoroughly investigated. For this purpose, both rugate filters with and without hydrogel microgel on top are immersed in ethanol/water mixtures possessing different compositions and NaCl solutions. Reflectance spectra of all samples are taken and analyzed concerning the spectral positions and reflectance intensity of the strong peak related to the photonic crystal rugate peak as well as the side bands resulting from Fabry–Pérot interference at the interfaces bordering the porous silicon. For the latter analysis, a Fourier transform is applied to the side bands for calculating the effective optical thickness (EOT). Thereby it can be shown that the spectral position of both the rugate peak and the EOT peak is best suited for monitoring refractive index changes in the immersion medium whereas the swelling and collapse of the stimuli‐responsive hydrogel microgel can be only detected by variations in the amplitude of the rugate peak and the EOT peak. These results are confirmed by simulations using a simple geometrical model and shall serve as guide for developing tailor‐made optical sensors.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134973534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andreas Eigen, Victoria Schmidt, Marco Sarcletti, Selina Freygang, Andreas Hartmann‐Bausewein, Vanessa Schneider, Anna Zehetmeier, Vincent Mauritz, Lukas Müller, Henrik Gaß, Linda Rockmann, Ryan W. Crisp, Marcus Halik
Abstract Many charged organic molecules behave as persistent and hazardous pollutants with harmful effects on human health and ecosystems. They are widely distributed related to their charged molecular structure that provides water solubility. In order to track the fate and behavior of such pollutants, charged dyes with specific absorption in the visible spectra serve as convenient model compounds. We provide a platform of smart adsorbers that efficiently remediate positively and negatively charged dyes (crystal violet and Amaranth) from water. Metal oxide nanoparticles serve as a core with an intrinsically large surface area. The surface potential was tuned towards positive or negative by decorating the cores with self‐assembled monolayers of dedicated long‐chained phosphonic acid derivatives. Selective remediation of the dyes was obtained with corresponding oppositely charged core‐shell nanoparticles. Mixed dye solution can be cleaned by a cascade approach or by applying both particle systems simultaneously. The removal efficiency was determined as a function of particle concentration via UV‐spectroscopy. The results of remediation experiments at different pH values and using superparamagnetic iron oxide nanoparticle cores lead to a simple process with recycling capability.
{"title":"Remediation of charged organic pollutants—binding motifs for highly efficient water cleaning with nanoparticles","authors":"Andreas Eigen, Victoria Schmidt, Marco Sarcletti, Selina Freygang, Andreas Hartmann‐Bausewein, Vanessa Schneider, Anna Zehetmeier, Vincent Mauritz, Lukas Müller, Henrik Gaß, Linda Rockmann, Ryan W. Crisp, Marcus Halik","doi":"10.1002/nano.202300130","DOIUrl":"https://doi.org/10.1002/nano.202300130","url":null,"abstract":"Abstract Many charged organic molecules behave as persistent and hazardous pollutants with harmful effects on human health and ecosystems. They are widely distributed related to their charged molecular structure that provides water solubility. In order to track the fate and behavior of such pollutants, charged dyes with specific absorption in the visible spectra serve as convenient model compounds. We provide a platform of smart adsorbers that efficiently remediate positively and negatively charged dyes (crystal violet and Amaranth) from water. Metal oxide nanoparticles serve as a core with an intrinsically large surface area. The surface potential was tuned towards positive or negative by decorating the cores with self‐assembled monolayers of dedicated long‐chained phosphonic acid derivatives. Selective remediation of the dyes was obtained with corresponding oppositely charged core‐shell nanoparticles. Mixed dye solution can be cleaned by a cascade approach or by applying both particle systems simultaneously. The removal efficiency was determined as a function of particle concentration via UV‐spectroscopy. The results of remediation experiments at different pH values and using superparamagnetic iron oxide nanoparticle cores lead to a simple process with recycling capability.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136237406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jianyi Xu, Guofang Zhang, Xin Zhao, Feng Hu, Dandan Ke
In this study, the perovskite‐type oxide LaFeO3 is treated by electroless Ni deposition with different reaction time and the electrochemical properties of the resulting material are investigated as the anode for MH‐Ni batteries. XRD, SEM, and TEM measurements reveal a uniform deposition of crystalline nickel on the oxide surface and a clear increase in the amount of Ni coating with the deposition time. The electrochemical analysis shows that the electroless deposition can significantly improve the maximum discharge capacity of the battery. Furthermore, the coated electrodes exhibit excellent activation performance and superior cyclic stability. With the increase in the reaction temperature, improvements in the discharge ability, exchange current density, and diffusing coefficient of hydrogen are also observed.
{"title":"Surface modification of perovskite‐type oxide LaFeO3 with electroless nickel deposition for application in MH‐Ni batteries","authors":"Jianyi Xu, Guofang Zhang, Xin Zhao, Feng Hu, Dandan Ke","doi":"10.1002/nano.202300091","DOIUrl":"https://doi.org/10.1002/nano.202300091","url":null,"abstract":"In this study, the perovskite‐type oxide LaFeO3 is treated by electroless Ni deposition with different reaction time and the electrochemical properties of the resulting material are investigated as the anode for MH‐Ni batteries. XRD, SEM, and TEM measurements reveal a uniform deposition of crystalline nickel on the oxide surface and a clear increase in the amount of Ni coating with the deposition time. The electrochemical analysis shows that the electroless deposition can significantly improve the maximum discharge capacity of the battery. Furthermore, the coated electrodes exhibit excellent activation performance and superior cyclic stability. With the increase in the reaction temperature, improvements in the discharge ability, exchange current density, and diffusing coefficient of hydrogen are also observed.","PeriodicalId":74238,"journal":{"name":"Nano select : open access","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136236672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}