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A critical selection of the recent literature reports on the use of photosynthetic and photoresponsive bacteria as a source of materials for optoelectronics and photonic devices is discussed, together with the applications foreseen in solar energy conversion and storage and light information technologies. The use of both photoactive cellular components and entire living cells is reviewed, aiming to highlight the great conceptual impact of these studies. These studies point out possible deep changes in the paradigm of design, and synthesis of materials and devices for optoelectronics. Although the possible technological impact of this technology is still hard to be predicted, these studies advance the understanding of photonics of living organisms and develop new intriguing concepts in biomaterials research.  相似文献   

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Bioelectronic implantable devices are adept at facilitating continuous monitoring of health and enabling the early detection of diseases, offering insights into the physiological conditions of various bodily organs. Furthermore, these advanced systems have therapeutic capabilities in neuromodulation, demonstrating their efficacy in addressing diverse medical conditions through the precise delivery of stimuli directly to specific targets. This comprehensive review explores developments and applications of bioelectronic devices within the biomedical field. Special emphasis is placed on the evolution of closed-loop systems, which stand out for their dynamic treatment adjustments based on real-time physiological feedback. The integration of Artificial Intelligence (AI) and edge computing technologies is discussed, which significantly bolster the diagnostic and therapeutic functions of these devices. By addressing elemental analyses, current challenges, and future directions in implantable devices, the review aims to guide the pathway for advances in bioelectronic devices.  相似文献   

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For the biofunctionalization of electronic devices, polymer brushes can provide a route which allows combining the advantages of other commonly used approaches, such as immobilization of functional biomolecules via self assembled monolayers or coated polymer matrices: high stability and loading capacity, efficient electron transport, and excellent biocompatibility. In the work presented here, poly(methacrylic acid) brushes are prepared by self‐initiated photografting and photopolymerization on diamond electrodes. In this straightforward process no prior grafting of initiators is required since the initiation of the polymerization can be conveniently controlled by the hydrogen or oxygen termination of the diamond surface. Boron doped nanocrystalline diamond as an electrode material provides extreme chemical inertness and stability, inherent biocompatibility, and superior electrochemical properties, such as the large accessible potential window and low background currents. As a proof of concept we demonstrate the amperometric detection of glucose by polymer brushes covalently modified with the redox enzyme glucose oxidase and aminomethyl ferrocene as electron mediator. Characterization by X‐ray photoelectron spectroscopy and atomic force microscopy both indicate a high loading of the ferrocene mediator. Consistently, electrochemical cyclic voltammetry shows a multilayer equivalent loading of ferrocene and highly efficient electron transfer throughout the polymer film. Overall, functionalized polymer brushes can provide a promising platform for the immobilization and electrical wiring of biomolecules for bioelectronic and biosensing applications.  相似文献   

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Organic bioelectronic sensors are gaining momentum as they can combine high‐performance sensing level with flexible large‐area processable materials. This opens to potentially highly powerful sensing systems for point‐of‐care health monitoring and diagnostics at low cost. Prominent to detect biochemical recognition events, are electrolyte‐gated organic field‐effect transistors (EGOFETs) and organic electrochemical transistors (OECTs) as they are easily fabricated and operated. EGOFETs are recently shown to be capable of label‐free single‐molecule detections, even in serum. This progress report aims to provide a critical perspective through a selected overview of the literature on both EGOFET and OECT biosensors. Attention is paid to correctly attribute them to the potentiometric and amperometric biosensor categories, which is important to set the right conditions for quantification purposes. Moreover, to deepen the understanding of the sensing mechanisms, with the support of unpublished data, focus is put on two among the most critical aspects, namely, the capacitance interplay and the role of Faradaic currents. The final aim is to provide a rationale of the functional mechanisms encompassing both EGOFET and OECT sensors, to improve materials and devices' designs taking advantage of the processes that enhance the sensing response enabling the extremely high‐performance level resulting in ultimate sensitivity, selectivity, and fast response.  相似文献   

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A comprehensive investigation of four polydiketopyrrolopyrroles (PDPPs) with increasing ethylene glycol (EG) content and varying nature of comonomer is presented, and guidelines for the design of efficient mixed ion-electron conductors (MIECs) are deduced. The studies in NaCl electrolyte-gated organic electrochemical transistors (OECTs) reveal that a high amount of EG on the DPP moiety is essential for MIEC. The PDPP containing 52 wt% EG exhibits a high volumetric capacitance of 338 F cm−3 (at 0.8 V), a high hole mobility in aqueous medium (0.13 cm2 V−1 s−1), and a μC* product of 45 F cm−1 V−1 s−1. OECTs using this polymer retain 97% of the initial drain-current after 1200 cycles (90 min of continuous operation). In a cell growth medium, the OECT-performance is fully maintained as in the NaCl electrolyte. In vitro cytotoxicity and cell viability assays reveal the excellent cell compatibility of these novel systems, showing no toxicity after 24 h of culture. Due to the excellent OECT performance with a considerable cycling stability for 1200 cycles and an outstanding cell compatibility, these PDPPs render themselves viable for in vitro and in vivo bioelectronics.  相似文献   

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Specific detection of dopamine (DA) is achieved with organic neuromorphic devices with no specific recognition function in an electrolyte solution. The response to voltage pulses consists of amplitude‐depressed current spiking mimicking the short‐term plasticity (STP) of synapses. An equivalent circuit hints that the STP timescale of the device arises from the capacitance and resistance of the poly(3,4‐ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) in series with the electrolyte resistance. Both the capacitance and resistance of PEDOT:PSS change with solution compositions. Dose curves are constructed from the STP timescale for each DA metabolite from pM to mM range of concentrations. The STP response of DA is distinctive from the other metabolites even when differences are by one functional group. Both STP and sensitivity to DA are larger across the patho‐physiological range with respect to those to DA metabolites. Density functional theory calculations hint to a stronger hydrogen bond pattern of DA ammonium compared to cationic metabolites. The exponential correlation between STP and the binding energy of DA metabolites interacting with PEDOT:PSS indicates that the slow dynamics of ionic species in and out PEDOT:PSS is the origin of the neuromorphic STP. The sensing framework discriminates differences of nonspecific interactions of few kcal mol?1, corresponding to one functional group in the molecule.  相似文献   

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Organic electrochemical transistors (OECTs) exhibit strong potential for various applications in bioelectronics, especially as miniaturized, point‐of‐care biosensors, because of their efficient transducing ability. To date, however, the majority of reported OECTs have relied on p‐type (hole transporting) polymer mixed conductors, due to the limited number of n‐type (electron transporting) materials suitable for operation in aqueous electrolytes, and the low performance of those which exist. It is shown that a simple solvent‐engineering approach boosts the performance of OECTs comprising an n‐type, naphthalenediimide‐based copolymer in the channel. The addition of acetone, a rather bad solvent for the copolymer, in the chloroform‐based polymer solution leads to a three‐fold increase in OECT transconductance, as a result of the simultaneous increase in volumetric capacitance and electron mobility in the channel. The enhanced electrochemical activity of the polymer film allows high‐performance glucose sensors with a detection limit of 10 × 10−6 m of glucose and a dynamic range of more than eight orders of magnitude. The approach proposed introduces a new tool for concurrently improving the conduction of ionic and electronic charge carriers in polymer mixed conductors, which can be utilized for a number of bioelectronic applications relying on efficient OECT operation.  相似文献   

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Biochemical sensors are used for discrimination of biochemical species, concentration measurement, and so on. Because metamaterial responds to slight changes in the ambient refractive index, it is possible to realize ultrasensitive biochemical sensors. We designed and fabricated refractive index sensors using polarization independent metamaterial and examined their application as biochemical sensors. Refractive index sensitivity, concentration measurement, and DNA detection were carried out.  相似文献   

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A novel Ag–silica–Au hybrid device is developed that displays a long‐range plasmon transfer of Ag to Au leading to enhanced Raman scattering of molecules largely separated from the optically excited Ag surface. A nanoscopically rough Ag surface is coated by a silica spacer of variable thickness from ～1 to 21 nm and a thin Au film of ～25 nm thickness. The outer Au surface is further functionalized by a self‐assembled monolayer (SAM) for electrostatic binding of the heme protein cytochrome c (Cyt c) that serves as a Raman probe and model enzyme. High‐quality surface‐enhanced resonance Raman (SERR) spectra are obtained with 413 nm excitation, demonstrating that the enhancement results exclusively from excitation of Ag surface plasmons. The enhancement factor is estimated to be 2 × 104–8 × 103 for a separation of Cyt c from the Ag surface by 28–47 nm, corresponding to an attenuation of the enhancement by a factor of only 2–6 compared to Cyt c adsorbed directly on a SAM‐coated Ag electrode. Upon immobilization of Cyt c on the functionalized Ag–silica–Au device, the native structure and redox properties are preserved as demonstrated by time‐ and potential‐dependent SERR spectroscopy.  相似文献   

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Considering the improved detection of biological analytes for affinity analysis is highly desirable, a metasurface plasmon resonance (Meta-SPR)-based imaging system, incorporating a localized SPR sensing platform with different microfluidic systems and employing simple bright-field imaging, is established in this study. This system enables low-level analyte concentration analysis, ranging from 100 pm to 100 nm , with the real-time removal of nonspecific binding signals within the same device field of view. Combined with microfluidic systems and microdroplet spotting, it is possible to automatically measure the kinetic curves of a sample at ten concentration gradients or detect the specific responses of multiple samples in a single experiment simultaneously. This system can inexpensively and conveniently achieve complex detection functions, demonstrating an innovative breakthrough in sensor detection.  相似文献   

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An optical biosensor based on waveguided metallic photonic crystals (MPCs) is reported for the sensitive testing of biomolecular interactions, which provides practical approaches for the label‐free detection of specific bioreactions. The enhancement of the sensitivity or the amplification of the sensor signal by the coupling between the waveguide resonance mode and particle‐plasmon resonance (PPR) breaks through the “bottle‐neck” of the intrinsic response sensitivity defined by the spectral shift of the PPR. The success of this sensor is demonstrated by sensing the specific reaction between the HIV‐1 capsid protein (p24) antigen and the monoclonal anti‐p24 antibody, where the dynamics of the bioreactions can be recorded with a potentially high time resolution. This new sensor stands out due to its compact design and its new physics, compared with conventional devices, its simple operation, the simple fabrication of the MPC chip and the low cost of the whole system.  相似文献   

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The development of biomolecular imprinting over the last decade has raised promising perspectives in replacing natural antibodies with artificial antibodies. A significant number of reports have been dedicated to imprinting of organic and inorganic nanostructures, but very few were performed on nanomaterials with a transduction function. Herein, a relatively fast and efficient plasmonic hot spot‐localized surface imprinting of gold nanorods using reversible template immobilization and siloxane copolymerization is described. The technique enables a fine control of the imprinting process at the nanometer scale and provides a nanobiosensor with high selectivity and reusability. Proof of concept is established by the detection of neutrophil gelatinase‐associated lipocalin (NGAL), a biomarker for acute kidney injury, using localized surface plasmon resonance spectroscopy. The work represents a valuable step towards plasmonic nanobiosensors with synthetic antibodies for label‐free and cost‐efficient diagnostic assays. It is expected that this novel class of surface imprinted plasmonic nanomaterials will open up new possibilities in advancing biomedical applications of plasmonic nanostructures.  相似文献   

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A fabrication strategy of photoactive biohybrid electrodes based on the immobilization of the bacterial reaction center (RC) onto indium tin oxide (ITO) is proposed. The RC is an integral photoenzyme that converts photons into stable charge‐separated states with a quantum yield close to one. The photogenerated electron–hole pair can be eventually exploited, with suitable redox mediators, to produce photocurrents. To this purpose, RC must be effectively anchored on the electrode surface and simple strategies for its stable immobilization ensuring prolonged enzyme photoactivity are strongly desired. In this work, polydopamine (PDA), a polymer reminiscent of the natural melanin, is used to anchor the RC on the electrode surface. PDA is easily prepared in situ by spontaneous polymerization of dopamine in slightly alkaline aerated buffered RC solution. This reaction, carried out in the presence of an ITO substrate dipped into the solution, directly leads to a stable RC‐PDA/ITO photoelectrode with 20 nm film thickness and 50% of fully functional RC occupancy. Photocurrents densities recorded using this photoelectrode are comparable to those obtained with far more sophisticated immobilization techniques. The RC‐PDA films are fully characterized by visible–near‐infrared absorption spectroscopy, ellipsometry, atomic force, and scanning electron microscopies.  相似文献   

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Recent breakthroughs in bioelectronic devices have stemmed from developments involving nanocomposites. Sepsis, preeclampsia, vascular dementia, and heart disease are serious conditions that will benefit from the continuous monitoring of pulse pressure (PP) and temperature (T) to improve medical insights and care. However, current clinical instruments are bulky, and lacking discreetness, while nanocomposites currently lack measurement accuracy. A thin (<1 mm) electronic skin (e-skin) is developed utilizing nanocomposite micro-caviar (MC), diameter (D) ≈290 µm, based on confined silver nanowire (AgNW) networks and food-grade brown seaweed (BS). MCs are virtually invisible (transmittance >99%) and extremely electromechanically sensitive (gauge factor, G >200). In addition to a considerable temperature coefficient of resistance (TCR) of 4.58 ± 0.95% °C−1 and excellent signal stability, skin-interfaced devices measured cuff-less PP and skin T with an accuracy conducive to clinical instruments.  相似文献   

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Neuroelectronic devices are critical for the diagnosis and treatment of neuropsychiatric conditions, and are hypothesized to have many more applications. A wide variety of materials and approaches have been utilized to create innovative neuroelectronic device components, from the tissue interface and acquisition electronics to interconnects and encapsulation. Although traditional materials have a strong track record of stability and safety within a narrow range of use, many of their properties are suboptimal for chronic implantation in body tissue. Material advances harnessed to form all the components required for fully integrated neuroelectronic devices hold promise for improving the long‐term efficacy and biocompatibility of these devices within physiological environments. Here, it is aimed to provide a comprehensive overview of materials and devices used in translational neuroelectronics, from acquisition and stimulation interfaces to methods for power delivery and real time processing of neural signals.  相似文献   

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The long‐term success of photosynthetic organisms has resulted in their global superabundance, which is sustained by their widespread, continual mass‐production of the integral proteins that photocatalyze the chemical processes of natural photosynthesis. Here, a fast, general method to assemble multilayer films composed of one such photocatalytic protein complex, Photosystem I (PSI), onto a variety of substrates is reported. The resulting films, akin to the stacked thylakoid structures of leaves, consist of a protein matrix that is permeable to electrochemical mediators and contain a high concentration of photoelectrochemically active redox centers. These multilayer assemblies vastly outperform previously reported monolayer films of PSI in terms of photocurrent production when incorporated into an electrochemical system, and it is shown that these photocatalytic properties increase with the film thickness. These results demonstrate how the assembly of micron‐thick coatings of PSI on non‐biological substrates yields a biohybrid ensemble that manifests the photocatalytic activity of the film’s individual protein constituents, and represent significant progress toward affordable, biologically‐inspired renewable energy conversion platforms.  相似文献   

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