Search

The unique properties of electrochromic (EC) colour switching have been widely observed from molecular EC materials to π-conjugated polymers (CPs). However, either their coloured or transparent state or both are generally unstable at voltage off state (VOFF) losing their optical memory (OM). Therefore many efforts have been made to keep OM under VOFF. While the molecularly dissolved EC materials show poor OM due to the diffusion of the EC materials under VOFF, polymeric EC materials in thin film states afford a longer OM up to 200 s. The mechanism to reach a long OM at coloured and bleached states is fundamentally different. Therefore in order to reach optical memory at both coloured and transparent state under VOFF, called bistability, it is necessary to design polymers with a particular energy level as well as electrolytes. Ultimately, the side chain engineered ProDOTs show bistability in ionic liquids when their HOMO energy level is lower than the fermi level of the electrode. In this chapter we will review several approaches to achieve bistability in electrochromic devices as well as windows, in particular, focusing on the mechanism for bistable electrochromism in polymer thin films and current status of the related research.

International audience; We demonstrate the soft realization of a new generation of functional hybrid van der Waals (vdW) heterostructures alternating two-dimensional (2D) materials and surface-confined supramolecular self-assemblies of porous crystals into three-dimensional (3D) stacks. We show that graphene can be transferred on top of a graphite-confined self-assembled 2D porous network, the cavities of which might be filled with functional guests. Subsequent growth of a new 2D host-guest self-assembled monolayer on top of this intermediate vdW heterostructure further extends it into the third dimension. Thus, this versatile approach, potentially not limited in the number of layers, allows creating on demand sequences by the careful choice of the 2D materials and of the presence or not and choice of guest molecules and permits to envisage innovative structures such as record-density bulk heterojunctions.

Smart windows tend to integrate multiple functions with the purpose of controlling external or sunlight input, self‐power functionality, and display functionality. Among the several chromogenic mechanisms, electrochromic methods are fast and simple to control. Moreover, electrochemical principles for smart windows offer easier integration of functionalities due to the integrative principles in common working mechanisms for color, energy, and information carrier controls. Thus efforts toward the combination of functionalities have led to synergetic and technical breakthroughs over the years. Here, the recent electrochromic research on the integration of different functionalities will be presented along with the development of new electrochromic polymers and nanostructurization.

With the growth of photoenergy harvesting and thermal engineering, photothermal materials (PTMs) have attracted substantial interest due to their unique functions such as localized heat generation, spatiotemporal thermal controllability, invisibility, and light harvesting capabilities. In particular, π-conjugated organic PTMs show advantages over inorganic or metallic PTMs in thin film applications due to their large light absorptivity, ease of synthesis and tunability of molecular structures for realizing high NIR absorption, flexibility, and solution processability. This review is intended to provide an overview of organic PTMs, including both molecular and polymeric PTMs. A description of the photothermal (PT) effect and conversion efficiency (ηPT ) for organic films is provided. After that, the chemical structure and optical properties of organic PTMs are discussed. Finally, emerging applications of organic PT films from the perspective of spatiotemporal thermal engineering principles are illustrated.

Correction for ‘Beyond “decorative” 2D supramolecular self-assembly: strategies towards functional surfaces for nanotechnology’ by Lydia Sosa-Vargas et al., Mater. Horiz., 2017, 4, 570–583, DOI: 10.1039/C7MH00127D.

Background Soluble inflammatory mediators are known to exacerbate sepsis-induced acute kidney injury (AKI). Continuous renal replacement therapy (CRRT) has been suggested to play a part in immunomodulation by cytokine removal. However, the effect of continuous venovenous hemodiafiltration (CVVHDF) dose on inflammatory cytokine removal and its influence on patient outcomes are not yet clear. Study Design Prospective, randomized, controlled, open-label trial. Setting & Participants Septic patients with AKI receiving CVVHDF for AKI. Intervention Conventional (40mL/kg/h) and high (80mL/kg/h) doses of CVVHDF for the duration of CRRT. Outcomes Patient and kidney survival at 28 and 90 days, circulating cytokine levels. Results 212 patients were randomly assigned into 2 groups. Mean age was 62.1 years, and 138 (65.1%) were men. Mean intervention durations were 5.4 and 6.2 days for the conventional- and high-dose groups, respectively. There were no differences in 28-day mortality (HR, 1.02; 95% CI, 0.73-1.43; P =0.9) or 28-day kidney survival (HR, 0.96; 95% CI, 0.48-1.93; P =0.9) between groups. High-dose CVVHDF, but not the conventional dose, significantly reduced interleukin 6 (IL-6), IL-8, IL-1b, and IL-10 levels. There were no differences in the development of electrolyte disturbances between the conventional- and high-dose groups. Limitations Small sample size. Only the predilution CVVHDF method was used and initiation criteria were not controlled. Conclusions High CVVHDF dose did not improve patient outcomes despite its significant influence on inflammatory cytokine removal. CRRT-induced immunomodulation may not be sufficient to influence clinical end points.

The arginylation branch of the N-end rule pathway is a ubiquitin-mediated proteolytic system in which post-translational conjugation of Arg by ATE1-encoded Arg-tRNA-protein transferase to N-terminal Asp, Glu, or oxidized Cys residues generates essential degradation signals. Here, we characterized the ATE1-/- mice and identified the essential role of N-terminal arginylation in neural tube development. ATE1-null mice showed severe intracerebral hemorrhages and cystic space near the neural tubes. Expression of ATE1 was prominent in the developing brain and spinal cord, and this pattern overlapped with the migration path of neural stem cells. The ATE1-/- brain showed defective G-protein signaling. Finally, we observed reduced mitosis in ATE1-/- neuroepithelium and a significantly higher nitric oxide concentration in the ATE1-/- brain. Our results strongly suggest that the crucial role of ATE1 in neural tube development is directly related to proper turn-over of the RGS4 protein, which participate in the oxygen-sensing mechanism in the cells. [BMB Reports 2016; 49(8): 443-448]

In this study, maltenes of atmospheric pressure residue oils were fractionated into five fractions and the fractions were examined by elemental analysis, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), and 1H nuclear magnetic resonance (NMR) spectroscopy. The obtained data were compared to examine the correlations among the data. The correlation coefficients (R2) were 0.88 and 0.89 respectively between the N and S contents determined by elemental analysis and summed relative abundances of N and S containing compounds observed by FT-ICR MS. Especially, correlation between S content and summed relative abundances of S containing compounds was observed. Further, correlation between %1Hnon-aro determined from NMR data and %Cnon-aro obtained from FT-ICR MS data was observed. %1Hnon-aro was calculated from the relative summed area of peaks in the non-aromatic region (0.5–4.5 ppm) of the NMR spectra. %Cnon-aro values were calculated from double bond equivalence values by assuming linear ...

목적: 급성 ST 분절 상승 심근경색증 환자에서 최초 의료접촉 방식 및 이에 따른 특성과 시간과의 관계를 조사했다. 방법: 전북 권역심혈관센터 데이터베이스에 등록된 527명의 일차적 관상동맥 중재시술을 받았던 급성 ST 분절 상승심근경색증 환자를 대상으로 의료 접촉 방식에 따른 일반적특징, 사회적 요인 및 시간 지연에 대한 예측 인자에 대해 조사했다. 결과: 전체 환자 중에서 28.8%만이 119를 이용했으며, 이들은 심부전, 심인성 쇼크 등의 임상 양상이 더 좋지 않았다. 최초 119를 이용하였어도 36.2%의 환자가 중재시술이 불가능한 병원으로 이송되었고 이들은 유의하게 증상 발생 후 관상동맥 중재술 시행까지 시간이 지연되었다(211.3 ± 358.0분vs. 320.2 ± 374.6분, p = 0.034). 증상 발생 후 관상동맥 중재술 시행까지 시간 단축의 독립적인 요인으로는 119를 이용(OR = 0.4, p < 0.001)하는 것과 이전 관상동맥 중재술 기왕력(OR = 0.4, p = 0.033)이었으며, 시간 지연의 독립적인 요인으로는 65세 이상의 고령(OR = 1.9, p = 0.003)과 중재술이 불가능한 병원을 먼저 내원한 경우(OR = 2.0, p < 0.001)였다. 결론: 전북 권역 심근경색증 환자들은 낮은 119 이용률을 보이며, 상당수가 중재시술이 불가능한 병원으로 이송되고 있다. 심근경색증에 대한 증상 인지율을 높이고 증상이 시작되면 즉시 119 구급차를 이용하여 중재시술이 가능한 병원으로 방문하도록 하는 홍보 및 교육이 필요할 것으로 생각된다.

For the first time, an inorganic-organic hybrid polymer binder was used for the coating of hybrid composites on separators to enhance thermal stability and to prevent formation of lithium dendrite in lithium metal batteries. The fabricated hybrid-composite-coated separators exhibited minimal thermal shrinkage compared with the previous composite separators (5% change in dimension), maintenance of porosity (Gurley number ∼400 s/100 cm(3)), and high ionic conductivity (0.82 mS/cm). Lithium metal battery cell examinations with our hybrid-composite-coated separators revealed excellent C-rate and cyclability performance due to the prevention of lithium dendrite growth on the lithium anode even after 200 cycles under 0.2-5C (charge-discharge) conditions. The mechanism for lithium dendrite prevention was attributed to exceptional nanoscale surface mechanical properties of the hybrid composite coating layer compared with the lithium metal anode, as the elastic modulus of the hybrid-composite-coated separator far exceeded those of both the lithium metal anode and the required threshold for lithium metal dendrite prevention.

Tau is a cytosolic protein that functions in the assembly and stabilization of axonal microtubule networks. Its oligomerization may be the rate-limiting step of insoluble aggregate formation, which is a neuropathological hallmark of Alzheimer's disease (AD) and a number of other tauopathies. Recent evidence indicates that soluble tau oligomers are the toxic species for tau-mediated pathology during AD progression. Herein, we describe novel RNA aptamers that target human tau and were identified through an in vitro selection process. These aptamers significantly inhibited the oligomerization propensity of tau both in vitro and in cultured cell models of tauopathy without affecting the half-life of tau. Tauopathy model cells treated with the aptamers were less sensitized to proteotoxic stress induced by tau overexpression. Moreover, the tau aptamers significantly alleviated synthetic tau oligomer-mediated neurotoxicity and dendritic spine loss in primary hippocampal neurons. Thus, our study demonstrates that delaying tau assembly with RNA aptamers is an effective strategy for protecting cells under various neurodegenerative stresses originating from pathogenic tau oligomerization.

In this study, a preparatory-scale fractionation method was developed. To verify the effectiveness of this method, an oil sample was fractionated into five fractions, referred to as saturate, aro1, aro2, polar1, and polar2; these fractions were completely characterized by thin-layer chromatography–flame ionization detection (TLC–FID), field desorption (FD) and (+) atmospheric pressure photoionization (APPI) high-resolution mass spectrometry (HR-MS), and gas chromatography with an atomic emission detector (GC–AED). TLC–FID analysis was used to compare the results obtained by the fractionation method to those obtained from the conventional saturates, aromatics, resins, and asphaltenes (SARA) method. FD–MS was employed to characterize the hydrocarbon class compounds in the saturate and aro1 fractions. As observed from the FD–MS spectra, non-aromatic hydrocarbon compounds were abundant in saturates, while mono- and diaromatic compounds were abundant in the aro1 fraction. This result is in good agreement with ...

A dendrimer porphyrin (DP)-coated gold nanoshell (AuNS-DP) was prepared for the synergistic combination of photodyanmic and photothermal therapy. The resultant AuNS-DP successfully exhibited the generation of reactive oxygen species (ROS) as well as photothermal effect for the simultaneous application of photodynamic therapy (PDT) and photothermal therapy (PTT).

Energy saving electrochromic windows were achieved by controlling the interfacial charge transfer using low-HOMO level (EHOMO < −5 eV) π-conjugated polymers (CPs) as bistable electrochromic films and an ionic liquid as the electrolyte layer. It provided a long bistability (>90 min) at the voltage-off state with a high coloration efficiency (879 cm2 C−1).

We present a new polyethylene glycol-functionalized polysilsesquioxane, a ladder-like structured poly(poly(ethylene oxide)-co-methacryloxypropyl)silsesquioxane) (PEO-SQ) hybrid-type polymer gelator to fabricate hybrid ionogel electrolytes for lithium ion capacitors. The organic-inorganic hybrid polymer gelator contains not only an inorganic ladder-like polysilsesquioxane backbone for the thermal and electrochemical stability, but also dual organic pendant groups consisting of free-dangling PEO chains and unsaturated methacryloxypropyl groups for enhanced lithium ion dissociation and thermal curing function, respectively. The successful crosslinking of 1 M LiTFSI in N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (BMPTFSI) ionic liquid with only a small amount of PEO-SQ hybrid crosslinker (5 wt%) gave non-leaking ionogels with high thermal stability (⿼400 °C), large ionic conductivities, and excellent lithium ion capacitor C-rate performance and cyclability, comparable to those of neat ionic liquid electrolyte and superior over conventional organic ionogels fabricated with organic crosslinkers without PEO-moeities.

Polydopamine (PDA) is a bioinspired material and coating that offers diverse functional activities (e.g., photothermal, antioxidant, and antimicrobial) for a broad range of applications. Although PDA is reported to be redox active, the association between PDA's redox state and its functional performance has been difficult to discern because of PDA's complex structure and limitations in methods to characterize redox-based functions. Here, we use an electrochemical reverse engineering approach to confirm that PDA is redox-active and can repeatedly accept and donate electrons. We observed that the electron-donating ability of PDA offers the detrimental pro-oxidant effect of donating electrons to O2 to generate reactive oxygen species (ROS) or, alternatively, the beneficial antioxidant effect of quenching oxidative free radicals. Importantly, PDA's electron-donating ability depends on its redox state and is strongly influenced by external factors including metal ion binding as well as near-infrared (NIR) irradiation. Furthermore, we demonstrated that PDA possesses redox state-dependent antimicrobial properties in vitro and in vivo. We envision that clarification of PDA's redox activity will enable better understanding of PDA's context-dependent properties (e.g., antioxidant and pro-oxidant) and provide new insights for further applications of PDA. STATEMENT OF SIGNIFICANCE: We believe this is the first report to characterize the redox activities of polydopamine (PDA) and to relate these redox activities to functional properties important for various proposed applications of PDA. We observed that polydopamine nanoparticles 1) are redox-active; 2) can repeatedly donate and accept electrons; 3) can accept electrons from reducing agents (e.g., ascorbate), donate electrons to O2 to generate ROS, and donate electrons to free radicals to quench them; 4) have redox state-dependent electron-donating abilities that are strongly influenced by metal ion binding as well as NIR irradiation; and 5) have redox state-dependent antimicrobial activities.

We report a novel strategy for bridging information transfer between electronics and biological systems within microdevices. This strategy relies on our “electrobiofabrication” toolbox that uses electrode-induced signals to assemble biopolymer films at spatially defined sites and then electrochemically “activates” the films for signal processing capabilities. Compared to conventional electrode surface modification approaches, our signal-guided assembly and activation strategy provides on-demand electrode functionalization, and greatly simplifies microfluidic sensor design and fabrication. Specifically, a chitosan film is selectively localized in a microdevice and is covalently modified with phenolic species. The redox active properties of the phenolic species enable the film to transduce molecular to electronic signals (i.e., “molectronic”). The resulting “molectronic” sensors are shown to facilitate the electrochemical analysis in real time of biomolecules, including small molecules and enzymes, to cell-based measurements such as cytotoxicity. We believe this strategy provides an alternative, simple, and promising avenue for connecting electronics to biological systems within microfluidic platforms, and eventually will enrich our abilities to study biology in a variety of contexts.

Molecular communication offers an exciting vision, but realizing this vision will require a bridging of device-based electromagnetic modalities and biology's molecular modalities. We are exploring redox (reduction-oxidation) reactions as a means to span these modalities. Here we use the example of the biological material melanin to illustrate how electrical signals can be used to probe for important redox-based molecular information. However, redox-probing is not limited to abiotic materials, but can be extended to probing living systems. We envision that the coupling of redox-probing with synthetic biology will allow the information processing capabilities of biology to be integrated with the speed and power of microelectronics to help realize the molecular communication vision.

It was brought to our attention that there were errors in the original publication by Kim et al. [1]. [...].

Antibodies are common recognition elements for molecular detection but often the signals generated by their stoichiometric binding must be amplified to enhance sensitivity. Here, we report that an electrode coated with a catechol-chitosan redox capacitor can amplify the electrochemical signal generated from an alkaline phosphatase (AP) linked immunoassay. Specifically, the AP product p-aminophenol (PAP) undergoes redox-cycling in the redox capacitor to generate amplified oxidation currents. We estimate an 8-fold amplification associated with this redox-cycling in the capacitor (compared to detection by a bare electrode). Importantly, this capacitor-based amplification is generic and can be coupled to existing amplification approaches based on enzyme-linked catalysis or magnetic nanoparticle-based collection/concentration. Thus, the capacitor should enhance sensitivities in conventional immunoassays and also provide chemical to electrical signal transduction for emerging applications in molecular communication.

The actuator is implemented based on the conductive polymer layer which causes photothermal conversion through the light in the near infrared region. The photothermally induced heat from conducting polymer can be converted into other type of energy such as mechanical, electrical or chemical energy. Especially, photothermal energy conversion into mechanical energy gives a unique method for reversible change of multi-layered actuator from 2-dimensional to 3-dimensional structure by thermal expansion coefficient mismatch among the layers. Herein we present the effect of the layer composition on the photoactuation and demonstrate a light switchable photothermal sensor.

We present a perspective on microsystems integration aspects for concurrent cellular and molecular sensing in a lab-on-a-chip device. While of interest for a range of applications, very few - narrowly focused - examples of such devices can be found in the literature. Here, we approach the challenge from a systems level, considering sensor integration both in parallel and in series. Our study is specifically geared toward schizophrenia treatment, where concurrent blood monitoring of the antipsychotic clozapine and white blood cells could lead to improved treatment outcomes. We evaluate the critical system components for either design, namely plasma skimming (parallel) and in-blood clozapine detection (series). We find that plasma skimming is infeasible, but for the first time demonstrate direct detection of clozapine in whole blood. With a corresponding series-integrated microsystem, we finally demonstrate downstream white blood cell analysis on the same samples using impedance cytometry. We thus present the first lab-on-a-chip device capable of label- and reagent-free concurrent sensing of cellular and molecular markers. QC 20190528

Temocin, Zulfikar/0000-0001-7151-9772; Panzella, Lucia/0000-0002-2662-8205; Payne, Gregory/0000-0001-6638-9459 WOS: 000444792800003 Melanins are ubiquitous in nature, yet their functions remain poorly understood, because their structures and properties elude characterization by conventional methods. Since many of the proposed functions of melanins (e.g., antioxidant, pro-oxidant, and radical scavenging) involve an exchange of electrons, we developed an electrochemical reverse engineering methodology to probe the redox properties of melanin. This mediated electrochemical probing (MEP) method (i) characterizes insoluble melanin particles that are localized adjacent to an electrode within a permeable hydrogel film, (ii) employs diffusible mediators to shuttle electrons between the electrode and melanin sample, and (iii) imposes complex sequences of input voltages and analyzes output response characteristics (e.g., currents) to reveal redox properties. Here, we illustrate the versatility of MEP and review results demonstrating that melanins have reversible redox activities, can exchange electrons with various reductants and oxidants, and can quench radicals either by donating or accepting electrons. These results suggest possible biological functionalities for melanin and motivate the use of MEP for characterizing additional (i.e., synthesized) materials whose functions rely on redox properties. More broadly, MEP is revealing a richness to redox activities that has previously been inaccessible to investigation. United States National Science FoundationNational Science Foundation (NSF) [DMREF-1435957]; Department of Defense (Defense Threat Reduction Agency)United States Department of DefenseDefense Threat Reduction Agency [HDTRA1-13-1-0037, HDTRA1-15-1-0058] The authors gratefully acknowledge financial support from the United States National Science Foundation (No. DMREF-1435957) and the Department of Defense (Defense Threat Reduction Agency; Nos. HDTRA1-13-1-0037 and HDTRA1-15-1-0058).

Cancer-associated fibroblasts (CAFs) have emerged as one of the main factors related to cancer progression, however, the conversion mechanism of normal fibroblasts (NOFs) to CAFs has not been well elucidated. The aim of this study was to investigate the underlying mechanism of CAF transformation from NOFs in oral squamous cell carcinoma (OSCC). This study found that NOFs exposed to OSCC cells transformed to senescent cells. The cytokine antibody array showed the highest secretion levels of IL-6 and CXCL1 in NOFs co-cultured with OSCC cells. Despite that both IL-6 and CXCL1 induced the senescent phenotype of CAFs, CXCL1 secretion showed a cancer-specific response to transform NOFs into CAFs in OSCC, whereas IL-6 secretion was eventuated by common co-culture condition. Further, CXCL1 was released from NOFs co-cultured with OSCC cells, however, CXCL1 was undetectable in mono-cultured NOFs or co-cultured OSCC cells with NOFs. Taken together, this study demonstrates that CXCL1 can transform NOFs into senescent CAFs via an autocrine mechanism. These data might contribute to further understanding of CAFs and to development of a potential therapeutic approach targeting cancer cells-CAFs interactions.

Water quality in four major river basin in Korea was managed with Total Maximum Daily Load (TMDL) System. The unit watershed in TMDL system has been evaluated with Target Water Quality (TWQ) assessment using average water quality, without considering its volume of water quantity. As results, although unit watershed are obtained its TWQ, its allocated loads were not satisfied and vice versa. To solve these problems, a number of TWQ assessments with using Load Duration Curve (LDC) have been studied at other watersheds. The purpose of this study was to evaluate achievement of TWQ with Flow Duration Curve (FDC) and Load Duration Curve(LDC) at 26 unit watersheds in Han river basin. The results showed that achievement rates in TWQ assessment with current method and with LDC were 50~56 % and 69~73%, respectively. Because of increasing about 20% of achievement rates with using LDC, the number of exceeded unit watershed at Han river Basin was decreased about 4~6 unit watersheds.Key words:Han-River, LDC (Load Duration Curve), Target Water Quality, TMDLs (Total Maximum Daily Loads)

Interpenetrating interfaces between a deuterated polystyrene (dPS) and the grafted substrates with the same chemical identity were characterized using neutron reflectivity (NR) measurements, where the PS-grafted substrates were prepared using a grafting-to approach with hydroxyl end-functionalized polystyrene (PSOH) in a dry brush regime. The characteristic brush thickness (h) and grafting density (σ) of PS-grafted layers were determined based on the chain length (or molecular weight, Mn) of PSOHs. The experimental interpenetration length (ξ) was measured at the interfaces, and the limiting plateau in ξ above which the value was independent of film thickness shifted toward higher values as the Mn of PSOH increased. Normalization by the deformed brush thickness (hd) of PS-grafted layer after interpenetration revealed that the experimental value of ξ/hd in a short and dense PS-grafted substrate, prepared with a low-molecular-weight PSOH, deviated markedly from the theoretical value, indicating significant additional stretching of the grafted chains to accommodate inter-mixing with the dPS chains.

Self-powered energy harvesters utilizing triboelectric effect and electrostatic induction have been widely studied, leading in the materials viewpoint to numerous material pairs for facile charge separation upon repetitive contacts with elaborate topological structures. Here, we present a simple but robust triboelectric platform based on a molecularly engineered surface triboelectric nanogenerator by self-assembled monolayers (METS). Triboelectric surface charge density of a substrate was readily controlled by the variation of end-functional groups of self-assembled monolayers (SAMs). In particular, by employing fluorine terminated SAMs, we are able to develop a METS with the maximum open circuit voltage and short circuit current of 105 V and 27 μA, respectively, under relatively gentle mechanical contacts with the 3N vertical force at 1.25 Hz. The power density of the device was 1.8 W/m2 at the load resistance of 10 MΩ more than 60 times greater than that of an unmodified dielectric/Al device. Moreover, ...

The single-step preparation of highly ordered mesoporous silica hybrid nanocomposites with conjugated polymers was explored using a novel cationic 3,4-propylenedioxythiophene (ProDOT) surfactant (PrS). The method does not require high-temperature calcination or a washing procedure. The combination of self-assembly of the silica surfactant and in situ polymerization of the ProDOT tail is responsible for creation of the mesoporosity with ultralarge pores, large pore volume, and electroactivity. As this novel material exhibits excellent textural parameters together with electrical conductivity, we believe that this could find potential applications in various fields. This novel concept of creating mesoporosity without a calcination process is a significant breakthrough in the field of mesoporous materials and the method can be further generalized as a rational preparation of various mesoporous hybrid materials having different structures and pore diameters. Refereed/Peer-reviewed

Clozapine is the most effective antipsychotic medication for schizophrenia, but it is underutilized because of the inability to effectively monitor its treatment efficacy and side effects. In this work, we demonstrate the first analytical micro-system for real-time monitoring of clozapine serum levels. An electrochemical lab-on-a-chip is developed and integrated with a catechol-chitosan redox cycling system. The microfabricated device incorporates 4 electrochemical reaction chambers with the capability of analyzing microliter-volume samples. Integration of the catechol-chitosan film amplifies the clozapine oxidative signal and improves the signal-to-noise ratio, which addresses sensitivity and selectivity challenges. Optimization of the redox cycling system fabrication parameters and analysis of various electrochemical techniques and data processing approaches is implemented to maximize clozapine detection performance. The device is tested with buffer samples containing clozapine and demonstrates a sensitivity of 54 μC mL cm−2 μg−1 and a limit-of-detection of 0.8 μg mL−1, a sensing performance similar to a counterpart macro-scale benchtop system. Importantly, the feasibility to differentiate between 0.33 μg mL−1 and 3.27 μg mL−1 clozapine concentrations in human serum without any preceding dilution or filtering procedures is demonstrated, a significant step towards utilizing point-of-care testing micro-systems for schizophrenia treatment management. With these micro-systems, we envision more effective and safe treatment that will enable fewer visits to the clinicians, decrease costs and patient burden.

To access smart optical theragnosis for cancer, an easily processable heterocyclic conjugated polymer (poly(sodium3-((3-methyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-3-yl)methoxy)propane-1-sulfonate), PPDS) nanoassembly is fabricated by a surfactant-free one-step process, without the laborious ordinary multicoating process. The conjugated nanoassembly, with a self-doped structure, provides strong absorbance in the near-infrared (NIR) range even in a neutral pH medium and exhibits excellent stability (>six months). In addition, the prepared PPDS nanoassembly shows a high photothermal conversion efficiency of 31.4% in organic photothermal nanoparticles. In particular, the PPDS nanoassembly is stably suspended in the biological medium without any additives. Through a simple immobilization with the anti-CD44 antibody, the prepared biomarker-targetable PPDS nanoassembly demonstrates specific targeting toward CD44 (expressed in stem-like cancer cells), allowing NIR absorbance imaging and the efficient targeted photothermal damaging of CD44-expressing cancer cells, from in vitro 3D mammospheres (similar to the practical structure of tumor in the body) to in vivo xenograft mice tumor models (breast cancer and fibrosarcoma). In this study, the most simplified preparation method is for this organic conjugated polymer-based nanoassembly by a molecular approach is reported, and demonstrated as a highly promising optical nanoagent for optical cancer theragnosis.

The local heating of poly(3,4-ethylenedioxythiophene) (PEDOT) by a photothermal effect directed by near-infrared (NIR) light induces unfolding of absorbed collagen triple helices, yielding soluble collagen single-helical structures. This dissociation of collagens allowed the harvesting of a living idiomorphic cell sheet, achieved upon irradiation with NIR light (λ=808 nm). The PEDOT layer was patterned and cells were successfully cultured on the patterned substrate. Cell sheets of various shapes mirroring the PEDOT pattern could be detached after a few minutes of irradiation with NIR light. The PEDOT patterns guided not only the entire shape of the cell sheets but also the spreading direction of the cells in the sheets. This photothermally induced dissociation of collagen provided a fast non-invasive harvesting method and tailor-made cell-sheet patterns.

Mental health disorders are complex and poorly understood but would benefit from real-time chemical analysis capable of assessing a patient's current status, personalizing a therapeutic action, and monitoring compliance. Here, an electrochemical sensor is reported for detecting the antipsychotic drug clozapine which is one of the most effective but under-utilized drugs for managing schizophrenia. This sensor employs a composite film of multiwalled carbon nanotubes (CNTs) embedded within a matrix of the aminopolysaccharide chitosan. Chitosan allows programmable assembly of the composite film at an electrode address while the CNTs confer electrocatalytic activities that displace interfering serum peaks from the voltage region where clozapine oxidation occurs. Using differential pulse voltammetry, high sensitivities (limit of detection 0.05 × 10–6m) are demonstrated for clozapine analysis in buffer. In serum, clozapine sensitivity is reduced by an order of magnitude but still sufficient for clinical analysis. Finally, the detection of clozapine from the serum of a schizophrenia patient is demonstrated without the need for serum pretreatment. In the long term, it is envisioned that the CNT-chitosan coated electrode could be integrated within a small array of other sensor types to enhance information-extraction to allow mental health disorders to be better managed and better understood.

We report a simple, cost-effective, and potentially scalable approach for the fabricating hierarchically porous CoOOH thin-film supercapacitors by combining a soft-templating and a chemical-bath deposition (CBD) method. The prepared electrode materials exhibit uniform morphology and highly ordered macropores, achieving a maximum specific capacitance of 387 F g−1 at a current density of 1 mA cm−2, with a high energy of 19 Wh kg−1 and power density of 1713 W kg−1. In addition, the porous CoOOH electrodes show good stability with a cycling efficiency >90 % after 5000 charge–discharge cycles, which could lead to the generation of novel energy-storage devices with better efficiencies. Refereed/Peer-reviewed

A useful strategy has been developed to fabricate carbon-nanotube-nickel (CNT-Ni) nanocomposites through atomic layer deposition (ALD) of Ni and chemical vapor deposition (CVD) of functionalized CNTs. Various techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), were used to characterize the morphology and the structure of as-prepared samples. It was confirmed that the products possess uniform Ni nanoparticles that are constructed by finely controlled deposition of Ni onto oxygen or bromine functionalized CNT surface. Electrochemical studies indicate that the CNT-Ni nanocomposites exhibit high electrocatalytic activity for glucose oxidation in alkaline solutions, which enables the products to be used in enzyme-free electrochemical sensors for glucose determination. It was demonstrated that the CNT-Ni nanocomposite-based glucose biosensor offers a variety of merits, such as a wide linear response window for glucose concentrations of 5 μM-2 mM, short response time (3 s), a low detection limit (2 μM), high sensitivity (1384.1 μA mM(-1) cm(-2)), and good selectivity and repeatability.

Individually, advances in microelectronics and biology transformed the way we live our lives. However, there remain few examples in which biology and electronics have been interfaced to create synergistic capabilities. We believe there are two major challenges to the integration of biological components into microelectronic systems: (i) assembly of the biological components at an electrode address, and (ii) communication between the assembled biological components and the underlying electrode. Chitosan possesses a unique combination of properties to meet these challenges and serve as an effective bio-device interface material. For assembly, chitosan’s pH-responsive film-forming properties allow it to “recognize” electrode-imposed signals and respond by self-assembling as a stable hydrogel film through a cathodic electrodeposition mechanism. A separate anodic electrodeposition mechanism was recently reported and this also allows chitosan hydrogel films to be assembled at an electrode address. Protein-based biofunctionality can be conferred to electrodeposited films through a variety of physical, chemical and biological methods. For communication, we are investigating redox-active catechol-modified chitosan films as an interface to bridge redox-based communication between biology and an electrode. Despite significant progress over the last decade, many questions still remain which warrants even deeper study of chitosan’s structure, properties, and functions.

Clozapine (CLZ), a dibenzodiazepine, is demonstrated as the optimal antipsychotic for patients suffering from treatment-resistant schizophrenia. Like many other drugs, understanding the concentration of CLZ in a patient’s blood is critical for managing the patients’ symptoms, side effects, and overall treatment efficacy. To that end, various electrochemical techniques have been adapted due to their capabilities in concentration-dependent sensing. An open question associated with electrochemical CLZ monitoring is whether drug–protein complexes (i.e., CLZ bound to native blood proteins, such as serum albumin (SA) or alpha-1 acid-glycoprotein (AAG)) contribute to electrochemical redox signals. Here, we investigate CLZ-sensing performance using fundamental electrochemical methods with respect to the impact of protein binding. Specifically, we test the activity of bound and free fractions of a mixture of CLZ and either bovine SA or human AAG. Results suggest that bound complexes do not significantly contribute to the electrochemical signal for mixtures of CLZ with AAG or SA. Moreover, the fraction of CLZ bound to protein is relatively constant at 31% (AAG) and 73% (SA) in isolation with varying concentrations of CLZ. Thus, electrochemical sensing can enable direct monitoring of only the unbound CLZ, previously only accessible via equilibrium dialysis. The methods utilized in this work offer potential as a blueprint in developing electrochemical sensors for application to other redox-active medications with high protein binding more generally. This demonstrates that electrochemical sensing can be a new tool in accessing information not easily available previously, useful toward optimizing treatment regimens.

Catechols offer diverse properties and are used in biology to perform various functions that range from adhesion (e.g., mussel proteins) to neurotransmission (e.g., dopamine), and mimicking the capabilities of biological catechols have yielded important new materials (e.g., polydopamine). It is well known that catechols are also redox-active and we have observed that biomimetic catechol-modified chitosan films are redox-active and possess interesting molecular electronic properties. In particular, these films can accept, store and donate electrons, and thus offer redox-capacitor capabilities. We are enlisting these capabilities to bridge communication between biology and electronics. Specifically, we are investigating an interactive redox-probing approach to access redox-based chemical information and convert this information into an electrical modality that facilitates analysis by methods from signal processing. In this review, we describe the broad vision and then cite recent examples in which the catechol–chitosan redox-capacitor can assist in accessing and understanding chemical information. Further, this redox-capacitor can be coupled with synthetic biology to enhance the power of chemical information processing. Potentially, the progress with this biomimetic catechol–chitosan film may even help in understanding how biology uses the redox properties of catechols for redox signaling.

The conversion of photons to heat in the conductive polymer films causes local heating to increase temperature at the light exposed area. The resultant heat can be converted into other type of energy such as electrical, mechanical, or chemical energy. In particular, photothermal effect in conductive polymer layers could be used for structural changes of the 2D structures into a complex three-dimensional (3D) structure. Herein we report the preparation of photothermal conductive polymer layers (CPL) and the integration of CPLs into a 2D structured film, to optimize not only the light-to-heat but also 2D-to-3D structural conversion.