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1.
ACS Appl Mater Interfaces ; 16(35): 46771-46788, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39166375

ABSTRACT

Electronic skin (e-skin) is considered as a highly promising interface for human-computer interaction systems and wearable electronic devices. Through elaborate design and assembly of various materials, it possesses multiple characteristics similar to human skin, including remarkable flexibility, stretchability, sensitivity to temperature and humidity, biocompatibility, and efficient interfacial ion/electron transport capabilities. Here, we innovatively integrate multifunctional carbon quantum dots (CQDs), which exhibit conductivity, antibacterial properties, ultraviolet absorption, and fluorescence emission, with poly(acrylic acid) and glycerin (Gly) into a three-dimensional network structure of natural goatskin collagen fibers. Through a top-down design strategy enhanced by hydrogen bond reconstruction, we successfully fabricated a novel transparent e-skin (PAC-eSkin). This e-skin exhibited significant tensile properties (4.94 MPa of tensile strength and 263.42% of a maximum breaking elongation), while also possessing Young's modulus similar to human skin (2.32 MPa). It is noteworthy that the functionalized CQDs used was derived from discarded goat hair, and the addition of Gly gave PAC-eSkin excellent antifreezing and moisturizing properties. Due to the presence of ultrasmall CQDs, which creates efficient ion/electron transport channels within PAC-eSkin, it could rapidly sense human motion and physiological signals (with a gauge factor (GF) of 1.88). Furthermore, PAC-eSkin had the potential to replace traditional electrode patches for real-time monitoring of electrocardiogram, electromyogram, and electrooculogram signals, with a higher SNR (signal-to-noise ratio) of 25.1 dB. Additionally, the customizable size and shape of PAC-eSkin offer vast possibilities for the construction of single-electrode triboelectric nanogenerator systems. We have reason to believe that the design and development of this transparent e-skin based on CQDs-functionalized dermal collagen matrices can pave a new way for innovations in human-computer interaction interfaces and their sensing application in diverse scenarios.


Subject(s)
Carbon , Quantum Dots , Wearable Electronic Devices , Quantum Dots/chemistry , Humans , Carbon/chemistry , Animals , Acrylic Resins/chemistry , Glycerol/chemistry , Goats , Dermis , Tensile Strength , Collagen/chemistry , Electric Conductivity
2.
Biomacromolecules ; 25(8): 5359-5373, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39045793

ABSTRACT

Inspired by the animal skin fiber network, we developed an electronic skin (e-skin) utilizing natural sheepskin as the primary substrate. This innovative design addresses the limitations of conventional e-skins, including inadequate mechanical strength, overly complex artificial network construction, and limited health monitoring capabilities. This e-skin successfully retains the structure and properties of natural sheepskin while exhibiting exceptional mechanical strength (with a breaking strength of 4.01 MPa) and high elongation (with an elongation at a break of 304.8%). Moreover, it possesses various desirable attributes such as electrical conductivity, antibacterial properties, biocompatibility, and environmental stability. In addition, this e-skin has the advantage of diverse data collection (joint movement, bioelectricity, foot health detection, and speech disorder communication systems). Therefore, this e-skin breaks the traditional construction strategy and single-mode application and is expected to become an ideal material for building smart sensor devices.


Subject(s)
Wearable Electronic Devices , Humans , Animals , Monitoring, Physiologic/methods , Monitoring, Physiologic/instrumentation , Skin/pathology , Electric Conductivity , Biocompatible Materials/chemistry
3.
J Mater Chem B ; 12(28): 6940-6958, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-38912903

ABSTRACT

Conductive hydrogels (CHs) with high sensitivity and multifunctional property are considered as excellent materials for wearable devices and flexible electronics. Surface synapses and internal multilayered structures are key factors for highly sensitive pressure sensors. Nevertheless, current CHs lack environmental adaptability, multifunctional perception, and instrument portability, which seriously hinders their application as sensors. Here, waste collagen fibers (buffing dust of leather), polyvinyl alcohol (PVA) and gelatin (Gel) were used as the basic framework of the hydrogel, loaded with a conductive material (silver nanoparticles (BD-CQDs@AgNPs)) and an anti-freezing moisturizer (glycerol (Gly)), resulting in a multifunctional conductive organohydrogel (BPGC-Gly). As a temperature and humidity sensor, it demonstrated an excellent temperature response range (-20-60 °C) and was capable of rapid response (2.4 s) and recovery (1.6 s) to human breathing. As a strain/pressure sensor, it allowed real-time monitoring of human movement and had a high low-pressure sensitivity (S = 4.26 kPa-1, 0-12.5 kPa). Interestingly, BPGC-Gly could also be used as a portable bioelectrode or the acquisition, monitoring and analysis of EMG/ECG signals. In this work, BPGC-Gly was assembled with wireless transmission to achieve multimodal heath detection, which opens new avenues for multi-responsive CHs, comprehensive human health monitoring and next-generation wearable electronic skin (e-skin).


Subject(s)
Collagen , Electric Conductivity , Hydrogels , Silver , Wearable Electronic Devices , Hydrogels/chemistry , Humans , Silver/chemistry , Collagen/chemistry , Metal Nanoparticles/chemistry , Temperature , Particle Size
4.
Article in English | MEDLINE | ID: mdl-38676634

ABSTRACT

Conductive hydrogels are ideal materials for intelligent medical devices, human-machine interfaces, and flexible bioelectrodes due to their adjustable mechanical properties and electrical responsiveness, whereas it is still a great challenge to achieve the integration of excellent flexibility and biocompatibility into one hydrogel sensor while also incorporating self-healing, self-adhesion, environmental tolerance, and antimicrobial properties. Here, a nanocomposite conductive organohydrogel was constructed by using collagen (Col), alginate-derived carbon quantum dots (OSA-CQDs), poly(acrylic acid) (PAA), ethylene glycol reduced AgNPs, and Fe3+ ions. Depending on OSA-CQDs with multiple chemical binding sites and high specific surface area as cross-linkers, while coupling highly biologically active Col chains and PAA chains are serving as an energy dissipation module, the resulting organohydrogel exhibited excellent flexibility (795% of strain, 193 kPa of strength), high cell compatibility (>95% survival rate), self-healing efficiency (HE = 79.5%), antifreezing (-20 °C), moisturizing (>120 h), repeatable adhesion (strength >20 kPa, times >10), inhibitory activity against Escherichia coli and Staphylococcus aureus (9 and 21.5 cm2), conductivity, and strain sensitivity (σ = 1.34 S/m, gauge factor (GF) = 11.63). Based on the all-in-one integration of multifunction, the organohydrogel can collaboratively adapt to the multimode of strain sensing and electrophysiological sensing to realize wireless real-time monitoring of human activities and physiological health. Therefore, this work provides a new and common platform for the design and sensing of next-generation hydrogel-based smart wearable sensors.

5.
ACS Appl Mater Interfaces ; 15(34): 40975-40990, 2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37584619

ABSTRACT

Conductive hydrogels have attracted tremendous interest in the construction of flexible strain sensors and triboelectric nanogenerators (TENGs) owing to their good stretchability and adjustable properties. Nevertheless, how to simultaneously achieve high transparency, self-healing, adhesion, antibacterial, anti-freezing, anti-drying, and biocompatibility properties through a simple method remains a challenge. Herein, a transparent, freezing-tolerant, and multifunctional organohydrogel (PAOAM-PDO) as electrode for strain sensors and TENGs was constructed through a free radical polymerization in the 1,3-propanediol (PDO)/water binary solvent system, in which oxide sodium alginate, aminated gelatin, acrylic acid, and AlCl3 were used as raw materials. The obtained PAOAM-PDO exhibited good transparency (>90%), self-healing, adhesiveness, antibacterial property, good conductivity (1.13 S/m), and long-term environmental stability. The introduction of PDO endowed PAOAM-PDO with freezing resistance with a low freezing point of -60 °C, and PAOAM-PDO could serve as a protective skin barrier to prevent frostbite at low temperature. PAOAM-PDO could be assembled as strain sensors to monitor heterogeneous human movements with high strain sensitivity (gauge factor of 7.05, strain = 233%). Meanwhile, PAOAM-PDO could be further fabricated as a TENG with a "sandwich" structure in single electrode mode. Moreover, the resulting TENG achieved electrical outputs with simple hand tapping and served as a self-powered device to light light-emitting diodes. This work displays a feasible strategy to build environment-tolerant and multifunctional organohydrogels, which possess potential applications in the wearable electronics and self-powered devices.

6.
ACS Appl Mater Interfaces ; 15(9): 12350-12362, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36826788

ABSTRACT

Conductive hydrogels are ideal for flexible sensors, but it is still a challenge to produce such hydrogels with combined toughness, self-adhesion, self-healing, anti-freezing, moisturizing, and biocompatibility properties. Herein, inspired by natural skin, a highly stretchable, strain-sensitive, and multi-environmental stable collagen-based conductive organohydrogel was constructed by using collagen (Col), acrylic acid, dialdehyde carboxymethyl cellulose, 1,3-propylene glycol, and AlCl3. The resulting organohydrogel exhibited excellent tensile (strain >800%), repeatable adhesion (>10 times), self-healing [self-healing efficiency (SHE) ≈ 100%], anti-freezing (-60 °C), moisturizing (>20 d), and biocompatible properties. This organohydrogel also possessed good electrical conductivity (σ = 3.4 S/m) and strain-sensitive properties [GF (gauge factor) = 13.65 with the maximal strain of 400%]. Notably, the organohydrogel had a considerable low-temperature self-healing performance (SHE = 88% at -24 °C) and rapid underwater self-healing property (SHE = 92%, self-healing time <20 min). This type of strain sensor could not only accurately and continuously monitor the large-scale motions of the human body but also provide an accurate response to the human tiny motions. This work not only proposes a development strategy for a multifunctional conductive organohydrogel with multiple environmental stability but also provides potential research value for the construction of biomimetic electronic skin.


Subject(s)
Adhesives , Wearable Electronic Devices , Humans , Motion , Collagen , Hydrogels , Electric Conductivity
7.
ACS Appl Mater Interfaces ; 15(1): 2147-2162, 2023 Jan 11.
Article in English | MEDLINE | ID: mdl-36562537

ABSTRACT

Flexible sensing devices (FSDs) fabricated using conductive hydrogels have attracted researchers' extensive enthusiasm in recent years due to their versatility. Considering the complexity of their application environments, the integration of various functional characteristics (e.g., excellent mechanical, antibacterial, and antifreezing properties) is an important guarantee for FSDs to stably perform their applications in different environments. Herein, we developed a multifunctional conductive polyvinyl alcohol (PVA) organohydrogel PVA-CT-Ag-Al-Gly (PCAAG) by using a green, natural, and cheap biomass, chestnut tannin (CT), as a crosslinking agent, nano-silver particles (AgNPs) as an antimicrobial agent, aluminum trichloride (AlCl3) as a conducting medium, and the mixed water-glycerol as the solvent system. In this organohydrogel system, CT acted not only as the reducing and stabilizing agent for the preparation of antibacterial AgNPs but also as the crosslinking agent owing to its strong multiple hydrogen bonding interactions with PVA, realizing its multifunctional application. The PCAAG organohydrogel possessed outstanding physical and mechanical properties (350.54% of the maximum fracture strain and 1.55 MPa of the maximum tensile strength), considerable bacteriostatic effects against both Escherichia coli and Staphylococcus aureus, and excellent freeze resistance (it could function normally at -20 °C). The motion-monitoring sensor based on the PCAAG organohydrogel exhibited excellent specificity recognition for both large-amplitude (e.g., elbow bending, wrist bending, finger bending, running and walking, etc.) and small-amplitude (frowning and swallowing) human movements. The flexible keyboard constructed by using the PCAAG organohydrogel could easily achieve the transformation between digital signals and electrical signals, and the signal output had both specificity and stability. The velocity-monitoring sensor fabricated by using the PCAAG organohydrogel could accurately measure the speed of the object movement (less than 3% of relative error). In short, the present PCAAG organohydrogel solves the problems of the single application environment and a few application scenarios of traditional conductive hydrogels and possesses remarkable application potential as a multifunctional FSD in many fields such as artificial intelligence, sport management, soft robots, and human-computer interface.


Subject(s)
Artificial Intelligence , Tannins , Humans , Anti-Bacterial Agents/pharmacology , Motion , Electric Conductivity , Escherichia coli , Hydrogels
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(11): 1247-1251, 2022 Nov 10.
Article in Chinese | MEDLINE | ID: mdl-36317212

ABSTRACT

OBJECTIVE: To analyze the clinical features and pathogenic variant in a Chinese pedigree affected with cleidocranial dysplasia (CCD). METHODS: Clinical data of 8 patients from the pedigree was collected, including physical examination and X-ray images of head, face, spine, limbs, and mouth. Peripheral blood samples were collected from 6 affected members for the extraction of genomic DNA. The proband and other 3 patients were subjected to trio-whole exome sequencing. Candidate variant was verified by Sanger sequencing of the other 2 affected members from the pedigree. RESULTS: This pedigree has included 22 members (8 affected) from four generations. Genetic testing revealed that the proband has harbored a novel pathogenic variant of the RUNX2 gene [NM_001024630: c.1268_1277del (p.P425Afs*56)], which was inherited from her mother and carried by all affected members in the pedigree. The same variant was not detected among the unaffected members, suggesting co-segregation with the phenotype. CONCLUSION: The c.1268_1277del (p.P425Afs*56) variant of the RUNX2 gene probably underlay the pathogenesis of CCD in this pedigree. Genetic testing has facilitated the definite diagnosis and enabled prenatal diagnosis.


Subject(s)
Cleidocranial Dysplasia , Humans , Pregnancy , Female , Cleidocranial Dysplasia/genetics , Pedigree , Core Binding Factor Alpha 1 Subunit/genetics , Phenotype , China , Mutation
9.
ACS Appl Mater Interfaces ; 14(21): 24741-24754, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35580208

ABSTRACT

Tough, biocompatible, and conductive hydrogel-based strain sensors are attractive in the fields of human motion detection and wearable electronics, whereas it is still a great challenge to simultaneously integrate underwater adhesion and self-healing properties into one hydrogel sensor. Here, a highly stretchable, sensitive, and multifunctional polysaccharide-based dual-network hydrogel sensor was constructed using dialdehyde carboxymethyl cellulose (DCMC), chitosan (CS), poly(acrylic acid) (PAA), and aluminum ions (Al3+). The obtained DCMC/CS/PAA (DCP) composite hydrogels exhibit robust mechanical strength and good adhesive and self-healing properties, due to the reversible dynamic chemical bonds and physical interactions such as Schiff base bonds and metal coordination. The conductivity of hydrogel is 2.6 S/m, and the sensitivity (gauge factor (GF)) is up to 15.56. Notably, the DCP hydrogel shows excellent underwater repeatable adhesion to animal tissues and good self-healing properties in water (self-healing rate > 90%, self-healing time < 10 min). The DCP hydrogel strain sensor can sensitively monitor human motion including finger bending, smiling, and wrist pulse, and it can steadily detect human movement underwater. This work is expected to provide a new strategy for the design of high-performance intelligent sensors, particularly for applications in wet and underwater environments.


Subject(s)
Hydrogels , Wearable Electronic Devices , Animals , Electric Conductivity , Humans , Hydrogels/chemistry , Monitoring, Physiologic , Motion
10.
Carbohydr Polym ; 273: 118533, 2021 Dec 01.
Article in English | MEDLINE | ID: mdl-34560946

ABSTRACT

A sensor used to monitor tissue deformation requires good flexibility, stretchability, self-adhesion, cyto-compatibility, and antibacterial property. Here, we prepared hydrogel sensor based on O-carboxymethyl chitosan (O-CMCS) and poly(vinyl alcohol) (PVA) for monitoring human and organ motions. Based on the host-guest complexing of poly(ß-cyclodextrin) with diamantane, a cross-linker containing multiple aldehyde groups was prepared for cross-linking with O-CMCS through Schiff base linkages. Borax was used as the second cross-linker to cross-link PVA through dynamic borate ester bonds. Carbon nanotubes (CNTs) were added into the hydrogels to improve their electrical conductivity and mechanical properties. The obtained hydrogel exhibited rapid self-healing ability with healing efficiency as high as 97%-103% (in 15 s), good adhesion to human skin and wet organ, good antibacterial property, cyto-compatibility, and stretchability. Furthermore, the hydrogel sensor can monitor the respiratory movement of porcine lungs and the beating of rat hearts.


Subject(s)
Biosensing Techniques/instrumentation , Chitosan/analogs & derivatives , Hydrogels/chemistry , Polyvinyl Alcohol/chemistry , Tissue Adhesives/chemistry , Animals , Anti-Bacterial Agents/chemistry , Borates/chemistry , Chitosan/chemistry , Electric Conductivity , Humans , Monitoring, Physiologic , Nanotubes, Carbon/chemistry , Rats , Swine , Tensile Strength
11.
Macromol Rapid Commun ; 42(11): e2100049, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33723879

ABSTRACT

A new side-chain ferrocene (Fc)-containing polyelectrolyte has been synthesized by controlled ring-opening metathesis polymerization of a water-soluble Fc-containing norbornene-based quaternary ammonium salt, as well as the corresponding covalently cross-linked polyelectrolyte hydrogel. In order to provide Fc-containing supramolecular polyelectrolyte hydrogels whose swelling property is largely improved by host-guest interaction, a covalently cross-linked polyelectrolyte hydrogel is soaked into the ß-CD aqueous solution to form ß-CD@Fc supramolecular polyelectrolyte hydrogel, or alternatively the quaternary ammonium salt supramolecular monomer is first formed, then copolymerized with a crosslinking agent to fabricate the supramolecular hydrogel with better water absorption ability. All the Fc-containing hydrogels exhibited good redox-responsiveness with swelling-shrinking behaviors by chemically reversibly adjusting the disassembly/assembly of ß-CD@Fc inclusion complexes. This is the first example of side-chain Fc-containing polycationic supramolecular hydrogels possessing swelling-shrinking properties based on the splitting/combining of ß-CD and Fc units, and potential applications are expected as controlled drug delivery and actuators.


Subject(s)
Hydrogels , beta-Cyclodextrins , Metallocenes , Oxidation-Reduction , Polyelectrolytes
12.
ACS Appl Mater Interfaces ; 13(12): 14612-14622, 2021 Mar 31.
Article in English | MEDLINE | ID: mdl-33723988

ABSTRACT

Hydrogel-based flexible strain sensors have shown great potential in body movement tracking, early disease diagnosis, noninvasive treatment, electronic skins, and soft robotics. The good self-healing, biocompatible, sensitive and stretchable properties are the focus of hydrogel-based flexible strain sensors. Dual network (DN) hydrogels are hopeful to fabricate self-healing hydrogels with the above properties. Here, multifunctional DN hydrogels are prepared via a combination of host-guest interaction of ß-cyclodextrin and ferrocene with dynamic borate ester bonds of poly(vinyl alcohol) and borax. Carbon nanotubes are used to endow the DN hydrogels with good conductivity. The obtained DN composite hydrogels possess good biocompatibility, stretchability (436%), fracture strength (41.0 KPa), self-healing property (healing efficiency of 95%), and high tensile strain sensitivity (gauge factor of 5.9). The DN composite hydrogels are used as flexible strain sensors to detect different human motions. After cutting, the healed hydrogels also can monitor human motions and have good stability. In addition, the hydrogel sensors may track the respiratory movement of a pig lung in vitro. This work exhibits new ideas and approaches to develop multifunctional self-healing hydrogels for constructing flexible strain sensors.


Subject(s)
Ferrous Compounds/chemistry , Hydrogels/chemistry , Metallocenes/chemistry , Polyvinyl Alcohol/chemistry , Wearable Electronic Devices , beta-Cyclodextrins/chemistry , Biocompatible Materials/chemistry , Borates/chemistry , Electric Conductivity , Humans , Monitoring, Physiologic , Movement , Nanotubes, Carbon/chemistry , Organ Motion , Smart Materials/chemistry , Tensile Strength
13.
ACS Appl Mater Interfaces ; 13(9): 11344-11355, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33620195

ABSTRACT

Hydrogel-based wearable devices have attracted tremendous interest due to their potential applications in electronic skins, soft robotics, and sensors. However, it is still a challenge for hydrogel-based wearable devices to be integrated with high conductivity, a self-healing ability, remoldability, self-adhesiveness, good mechanical strength and high stretchability, good biocompatibility, and stimulus-responsiveness. Herein, multifunctional conductive composite hydrogels were fabricated by a simple one-pot method based on poly(vinyl alcohol) (PVA), sodium alginate (SA), and tannic acid (TA) using borax as a cross-linker. The composite hydrogel network was built by borate ester bonds and hydrogen bonds. The obtained hydrogel exhibited pH- and sugar-responsiveness, high stretchability (780% strain), and fast self-healing performance with healing efficiency (HE) as high as 93.56% without any external stimulus. Additionally, the hydrogel displayed considerable conductive behavior and stable changes of resistance with high sensitivity (gauge factor (GF) = 15.98 at a strain of 780%). The hydrogel was further applied as a strain sensor for monitoring large and tiny human motions with durable stability. Significantly, the healed hydrogel also showed good sensing behavior. This work broadens the avenue for the design and preparation of biocompatible polymer-based hydrogels to promote the application of hydrogel sensors with comfortable wearing feel and high sensitivity.


Subject(s)
Alginates/chemistry , Hydrogels/chemistry , Monitoring, Physiologic/instrumentation , Movement , Polyvinyl Alcohol/chemistry , Wearable Electronic Devices , Borates/chemistry , Electric Conductivity , Humans , Monitoring, Physiologic/methods , Pliability , Tannins/chemistry
14.
Des Monomers Polym ; 23(1): 141-154, 2020 Aug 30.
Article in English | MEDLINE | ID: mdl-33029082

ABSTRACT

Polynorbornenes, prepared by the 'living' and 'controlled' ring-opening metathesis polymerization (ROMP) method, have emerged as a stimuli-sensitive new class of polymer carriers. Herein, we reported a novel amphiphilic diblock polynorbornene, PNCHO-b-PNTEG, containing active benzaldehyde units, which exhibited good conjugating capacity to amino-containing molecules (e.g., doxorubicin (DOX)) via the pH-sensitive Schiff base linkage. The copolymer and its conjugate with DOX, DOX-PNCHO-b-PNTEG, were adequately analyzed by various techniques including 1H NMR, 13C NMR, gel permeation chromatography, etc. Especially, the formed conjugate of DOX-PNCHO-b-PNTEG could self-assemble into near-spherical micelles with the diameter of 81 ± 10 nm, and exhibit acid-triggered DOX release behavior, and the release rate could be adjusted by changing the environmental pH value. The excellent biological safety of PNCHO-b-PNTEG was further demonstrated by the results from both in vitro toxicity evaluation to murine fibroblast cells (L-929 cells) and in vivo evaluation of acute developmental toxicity and cell death in zebrafish embryos. Hence, the present polynorbornene-based PNCHO-b-PNTEG possesses great potential application as a biocompatible polymeric carrier and could be employed to fabricate various pH-sensitive conjugates.

15.
Chem Commun (Camb) ; 56(77): 11374-11385, 2020 Sep 29.
Article in English | MEDLINE | ID: mdl-32990300

ABSTRACT

Ferrocene-containing polymers have been investigated for more than six decades, and more recently modern synthetic methods have allowed the fabrication of precise polymers that contain a variety of transition-metal complexes. Trends are now oriented towards applications, such as optics, energy conversion and storage, electrochemistry, magnetics, electric conductors and biomedicine. Metal-sandwich complexes such as those of ferrocene type and other related complexes that present redox-robust groups in polymers, i.e. that are isolable in both their oxidized and reduced forms, are of particular interest, because it is possible to address them using electronic or photonic redox stimuli for application. Our research groups have called such complexes Electron-Reservoirs and introduced them in the main chain or in the side chains of well-defined polymers. For instance, polymers with ferrocene in the main chain or in the side chain are oxidized to stable polycationic polyelectrolytes only if ferrocene is part of a biferrocene unit, because biferrocene oxidation leads to the biferrocenium cation that is stabilized by the mixed valency. Then a group of several redox-robust iron sandwich complexes were fabricated and incorporated in precise polymers including multi-block copolymers whose controlled synthesis and block incorporation was achieved for instance using ring-opening-metathesis polymerization. Applications of this family of Electron-Reservoir-containing polymers includes electrochemically induced derivatization of electrodes by decorating them with these polymers, molecular recognition and redox sensing, electrochromics with multiple colours, generation of gold and silver nanoparticles of various size by reduction of gold(iii) and silver(i) precursors and their use for nanocatalysis towards depollution and biomedicine.

16.
J Inorg Biochem ; 193: 31-41, 2019 04.
Article in English | MEDLINE | ID: mdl-30669064

ABSTRACT

Supramolecular Janus compounds have recently attracted increasing attention owing to their dynamic reversible properties, distinct topological structures, and remarkable physicochemical characteristics, e.g., amphiphilicity, heterofunctionality, and high-density of terminal groups. Herein, a new redox-responsive supramolecular Janus device was designed and synthesized involving ß-cyclodextrin and 2-fold ferrocene host-guest interactions. The complex formation was analyzed via one-dimensional 1H NMR and two-dimensional Nuclear Overhauser Enhancement Spectroscopy. FeCl3 and ascorbic acid were used as oxidation and reduction triggers, respectively, to modulate the self-assembly behavior in water through complexation/dissociation of ß-cyclodextrin inclusion compounds resulting from redox-conversion of the ferrocenyl guest moieties. The redox-responsiveness of the obtained supramolecular micelles was studied via scanning electron microscopy and dynamic light scattering. Substrate-loading ability of the supramolecular micelles was confirmed with Rhodamine B, and the oxidation of ferrocenyl groups led to the release of the loaded cargos. The present work illustrates a valuable design example of supramolecular Janus systems using the host-guest complexation between ß-cyclodextrin and ferrocenyl structures. The present supramolecular micelle may be used as a promising molecular vehicle for application in the field of stimuli-responsive drug delivery.


Subject(s)
Dendrimers/chemistry , Drug Carriers/chemistry , Ferrous Compounds/chemistry , Rhodamines/chemistry , beta-Cyclodextrins/chemistry , Ascorbic Acid/chemistry , Chlorides/chemistry , Dendrimers/chemical synthesis , Drug Carriers/chemical synthesis , Drug Liberation , Ferric Compounds/chemistry , Ferrous Compounds/chemical synthesis , Fluorescent Dyes/chemistry , Micelles , Oxidation-Reduction
17.
J Colloid Interface Sci ; 533: 161-170, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30153593

ABSTRACT

A series of small-sized (about 2.0 nm) gold nanoparticles (AuNPs) with apparent lattice fringes are synthesized by NaBH4 reduction of HAuCl4 in the presence of stabilizing linear or dendronized 1,2,3-triazolyl-containing ferrocenyl polymers. These AuNPs show high catalytic activity for biphasic 4-nitrophenol (4-NP) reduction to 4-aminophenol (4-AP) by NaBH4. The lower generation G1 dendronized polymers (DPs) is a more efficient stabilizer for AuNP catalytic activity in the reduction of 4-NP than linear G0 polymers or bulky G2 DPs. The G1 DP-stabilized AuNPs are robust and easily recyclable, and the catalyst is recovered and reused at least twenty times with progressive smooth AuNP size increase along with some decrease of catalytic activity.

18.
Angew Chem Int Ed Engl ; 57(8): 2204-2208, 2018 02 19.
Article in English | MEDLINE | ID: mdl-29327792

ABSTRACT

Multi-block polymers are highly desirable for their addressable functions that are both unique and complementary among the blocks. With metal-containing polymers, the goal is even more challenging insofar as the metal properties may considerably extend the materials functions to sensing, catalysis, interaction with metal nanoparticles, and electro- or photochrome switching. Ring-opening metathesis polymerization (ROMP) has become available for the formation of living polymers using highly efficient initiators such as the 3rd generation Grubbs catalyst [RuCl2 (NHC)(=CHPh)(3-Br-C5 H4 N)2 ], 1. Among the 24 possibilities to introduce 4 blocks of metallopolymers into a tetrablock metallocopolymer by ROMP using the catalyst 1, two viable pathways are disclosed. The synthesis, characterization, electrochemistry, electron-transfer chemistry, and remarkable electrochromic properties of these new nanomaterials are presented.

19.
J Obstet Gynaecol Res ; 44(4): 655-662, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29316087

ABSTRACT

AIM: We aimed to explore the relation between the level of adipocyte fatty-acid binding protein (A-FABP) in the gestational period and related indices of glucolipid metabolism, and the possible mechanisms of occurrence and development of pre-eclampsia. METHODS: Seventy-six pre-eclampsia patients were enrolled and divided into the mild pre-eclampsia (n = 42) and severe pre-eclampsia (n = 34) groups. Forty-eight healthy pregnant women were selected as a control group. The indices of all participants were examined, including serum A-FABP, fasting insulin (FINS), fasting blood glucose, total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL), and homeostatic model assessment insulin resistance (HOMA-IR) index was calculated. After the delivery of the placenta, the level of A-FABP in the placenta was detected by immunochemistry. Then, the correlation between serum A-FABP and indices of glucolipid metabolism and placental A-FABP were analyzed. RESULTS: Serum A-FABP, FINS, TG, TC, HOMA-IR, and placental A-FABP were significantly higher in pre-eclampsia patients and the level of HDL was obviously lower than in the control group. Serum A-FABP was positively correlated with FINS, TG, TC, and HOMA-IR, and placental A-FABP was negatively correlated with HDL in pre-eclampsia patients. In the control group, serum A-FABP was positively correlated only with TG, and uncorrelated with the other indices (P > 0.05). CONCLUSION: The level of A-FABP was correlated with insulin resistance and indices of glucolipid metabolism in pre-eclampsia patients. High-levels of A-FABP might increase insulin resistance by causing glucose and lipid metabolism disorders and ultimately inducing the occurrence and development of pre-eclampsia.


Subject(s)
Blood Glucose/analysis , Cholesterol, HDL/blood , Fatty Acid-Binding Proteins/metabolism , Insulin Resistance , Insulin/blood , Lipoproteins, HDL/blood , Pre-Eclampsia/blood , Triglycerides/blood , Adult , Fatty Acid-Binding Proteins/blood , Female , Humans , Infant, Newborn , Pregnancy
20.
Macromol Rapid Commun ; 38(19)2017 Oct.
Article in English | MEDLINE | ID: mdl-28833809

ABSTRACT

First- and second-generation Percec-type dendronized ferrocenyl norbornene macromonomers containing, respectively, three and nine ferrocenyl termini are synthesized and polymerized by ring-opening metathesis polymerization using Grubbs' third-generation olefin metathesis catalyst with several monomer/catalyst feed ratios between 10 and 50. The rate of polymerization is highly dependent on the generation of the dendronized macromonomers, but all these ring-opening metathesis polymerization reactions are controlled, and near-quantitative monomer conversions are achieved. The numbers of ferrocenyl groups obtained are in agreement with the theoretical ones according to the cyclic voltammetry studies as determined using the Bard-Anson method.


Subject(s)
Alkenes/chemistry , Norbornanes/chemistry , Polymers/chemistry , Alkenes/chemical synthesis , Catalysis , Norbornanes/chemical synthesis , Polymerization , Polymers/chemical synthesis
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