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Johannesen Lauesen posted an update 6 hours, 43 minutes ago
224 μA μM-1 cm-2 at the Nano-PEDOT-COOH50% interface. Furthermore, the carboxylic acid groups provide an anchoring site for the stable immobilisation of an NADH-dependent dehydrogenase (i.e. lactate dehydrogenase), via EDC/S-NHS chemistry, for the fabrication of a Bio-Nano-PEDOT-based biosensor for lactate detection which had a response time of less than 10 s over the range of 0.05-1.8 mM. Our developed bio-Nano-PEDOT interface shows future potential for coupling with multi-biorecognition molecules via carboxylic acid groups for the development of a range of advanced all-polymer biosensors. Recent advances in electrochemical biosensors for pathogen detection are reviewed. Electrochemical biosensors for pathogen detection are broadly reviewed in terms of transduction elements, biorecognition elements, electrochemical techniques, and biosensor performance. Transduction elements are discussed in terms of electrode material and form factor. Biorecognition elements for pathogen detection, including antibodies, aptamers, and imprinted polymers, are discussed in terms of availability, production, and immobilization approach. Emerging areas of electrochemical biosensor design are reviewed, including electrode modification and transducer integration. Measurement formats for pathogen detection are classified in terms of sample preparation and secondary binding steps. Applications of electrochemical biosensors for the detection of pathogens in food and water safety, medical diagnostics, environmental monitoring, and bio-threat applications are highlighted. Future directions and challenges of electrochemical biosensors for pathogen detection are discussed, including wearable and conformal biosensors, detection of plant pathogens, multiplexed detection, reusable biosensors for process monitoring applications, and low-cost, disposable biosensors. A novel amperometric algae-based biosensor was developed for the detection of photosynthetic herbicides in river water. The green photosynthetic algae Chlamydomonas reinhardtii was immobilized on carbon black modified screen-printed electrodes, exploiting carbon black as smart nanomaterial to monitor changes in algae oxygen evolution during the photosynthetic process. The decrease of oxygen evolution, occurring in the presence of herbicides, results in a decrease of current signals by means of amperometric measurements, in an analyte concentration dependent manner. Atrazine as case study herbicide was detected in a concentration range of 0.1 and 50 μM, with a linear range from 0.1 to 5 μM and a detection limit of 1 nM. No interference was observed in presence of 100 ppb arsenic, 20 ppb copper, 5 ppb cadmium, 10 ppb lead, 10 ppb bisphenol A, and 1 ppb paraoxon, tested as safety limits. A ~25% matrix effect and satisfactory recovery values of 107 ± 10% and 96 ± 8% were obtained in river water for 3 and 5 μM of atrazine, respectively. Stability studies were also performed obtaining a high working stability up to 10 h and repeatability with an RSD of 1.1% (n = 12), as well as a good storage stability up to 3 weeks. The construction of dual mode sensor has gained tremendous attention due to its high accuracy and sensitivity compared with a single-response system. Herein, a novel dual mode sensing platform based on a 3-dimensional (3D) ZnCdS/ZnIn2S4 double-shelled dodecahedral cages (DSDCs) is fabricated as the electrochemical (EC) – photoelectrochemical (PEC) multifunctional signal amplification matrix for the highly selective detection of bovine hemoglobin (BHb). To achieve simple and fast detection of BHb, Au@Cu2O and SnO2/SnS2 are acted as EC – PEC signal indicators, respectively. More interestingly, the electroactive Au@Cu2O and photoactive SnO2/SnS2 are assembled on the 3D ZnCdS/ZnIn2S4 DSDCs, which could effectively increase the electron transfer process, consequently amplifying the readout of the dual mode responses. Besides, polydopamine (PDA) is used as a monomer for protein imprinting. Under the optimized conditions, the dual mode sensor exhibits a wide linear concentration range from 10-19 mg mL-1 to 10-1 mg mL-1 with a low detection limit 6.5 × 10-20 mg mL-1. Furthermore, the excellent selectivity, stability and acceptable reproducibility of the designed sensor will offer an alternation for the detection of other biomacromolecules in clinic diagnosis field. A biosensor has been developed based on disposable screen-printed electrode for recording the electrochemical fingerprint of plant leaf tissue. RGDyK nmr A thin layer of polydopamine functionalized graphene sheets was coated on the plant tissue modified electrode for signal enhancement. The voltammetric data recorded under different buffer solutions can be derived as patterns for species identification. As the distribution of electrochemical active compounds in plants is controlled by genes, these fingerprints can reflect differences at the genetic level between species. Therefore, the electrochemical fingerprint of plant tissues can be used for phylogenetic research without qualitative analysis. 19 species of Amaryllidaceae including A. africanus, Clivia miniata, Clivia nobilis, Crinum firmifolium, Crinum latifolium, Crinum moorei, Curculiga gracilis, Cyrtanthus breviflorus, Habranthus robustus, Haemanthus albiflos, Haemathus multiflorus, Hippeastrum rutilum, Hymenocallis littoralis, Leucojum aestivum, Sprekelia formosissima, Tulbaghia violacea, Zephyranthes grandiflora, Zephyranthes macrosiphon and Zephyranthes minima have been selected deliberately. The dendrogram deduced from the electrochemical fingerprint was compared with the molecular phylogenetics. The results indicate the electrochemical fingerprint-based phylogenetic study is a persuasive methodology for plant phylogenetic analysis. Multiple and sensitive detection of oncomiRs for accurate cancer diagnostics is still a challenge. Here, a synergetic amplification strategy was introduced by combining a MXene-based electrochemical signal amplification and a duplex-specific nuclease (DSN)-based amplification system for rapid, attomolar and concurrent quantification of multiple microRNAs on a single platform in total plasma. Synthesized MXene-Ti3C2Tx modified with 5 nm gold nanoparticles (AuNPs) was casted on a dual screen-printed gold electrode to host vast numbers of DNA probes identically co-immobilized on dedicated electrodes. Interestingly, presence of MXene provided biofouling resistance and enhanced the electrochemical signals by almost 4 folds of magnitude, attributed to its specious surface area and remarkable charge mobility. The 5 nm AuNPs were perfectly distributed within the whole flaky architect of the MXene to give rise to the electrochemical performance of MXene and provide the thiol-Au bonding feature. This synergetic strategy reduced the DSN-based biosensors’ assay time to 80 min, provided multiplexability, antifouling activity, substantial sensitivity and specificity (single mutation recognition).