The aim of this electrochemical study was to ascertain which type of electrochemically deposited carbonyl functionalized polymer represents the most suitable electrode substrate for direct covalent immobilization of biological catalysts (enzymes). For this purpose, a triad of amperometric biosensors differing in the type of conductive polymers (poly-vanillin, poly-trans-cinnamaldehyde, and poly-4-hydroxybenzaldehyde) and in the functioning of selected enzymes (tyrosinase and alkaline phosphatase) has been compared for the biosensing of neurotransmitters (dopamine, epinephrine, norepinephrine, and serotonin) and phenyl phosphates (p-aminophenyl phosphate and hydroquinone diphosphate). The individual layers of the polymers were electrochemically deposited onto commercially available screen-printed carbon electrodes (type C110) using repetitive potential cycling in the linear voltammetric mode. Their characterization was subsequently performed by SEM imaging and attenuated total reflectance FTIR spectroscopy. Molecules of enzymes were covalently bonded to the free carbonyl groups in polymers via the Schiff base formation, in some cases even with the use of special cross-linkers. The as-prepared biosensors have been examined using cyclic voltammetry and amperometric detection. In this way, the role of the carbonyl groups embedded in the polymeric structure was defined with respect to the efficiency of binding enzymes, and consequently, via the final (electro)analytical performance.

• Klíčová slova
• Schiff base formation, amperometric detection, carbonyl functional polymer, catalytic biosensor, electropolymerization, enzyme, phenolic compounds,
• MeSH
• biosenzitivní techniky * metody   MeSH
• elektrochemické techniky * metody   MeSH
• elektrody MeSH
• polymery chemie   MeSH
• reprodukovatelnost výsledků MeSH
• skot MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• polymery MeSH

New methodologies based on the principle of "sewage epidemiology" have been successfully applied before in the detection of illegal drugs. The study describes the idea of early detection of a virus, e.g., SARS-CoV-2, in wastewater in order to focus on the area of virus occurrence and supplement the results obtained from clinical examination. By monitoring temporal variation in viral loads in wastewater in combination with other analysis, a virus outbreak can be detected and its spread can be suppressed early. The use of biosensors for virus detection also seems to be an interesting application. Biosensors are highly sensitive, selective, and portable and offer a way for fast analysis. This manuscript provides an overview of the current situation in the area of wastewater analysis, including genetic sequencing regarding viral detection and the technological solution of an early warning system for wastewater monitoring based on biosensors.

• Klíčová slova
• COVID-19, PCR methods, SARS-CoV-2, biosensors, genetic sequencing, virus detection, wastewater monitoring,
• MeSH
• COVID-19 * MeSH
• epidemiologie odpadních vod * MeSH
• lidé MeSH
• mutace MeSH
• odpadní voda MeSH
• odpadní vody MeSH
• SARS-CoV-2 MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• odpadní voda MeSH
• odpadní vody MeSH

Leptospirosis is an underestimated tropical disease caused by the pathogenic Leptospira species and responsible for several serious health problems. Here, we aimed to develop an ultrasensitive DNA biosensor for the rapid and on-site detection of the Loa22 gene of Leptospira interrogans using a gold nanoparticle-carbon nanofiber composite (AuN/CNF)-based screen-printed electrode. Cyclic voltammetry and electrochemical impedance were performed for electrochemical analysis. The sensitivity of the sensor was 5431.74 μA/cm2/ng with a LOD (detection limit) of 0.0077 ng/μL using cyclic voltammetry. The developed DNA biosensor was found highly specific to the Loa22 gene of L. interrogans, with a storage stability at 4 °C for 180 days and a 6% loss of the initial response. This DNA-based sensor only takes 30 min for rapid detection of the pathogen, with a higher specificity and sensitivity. The promising results obtained suggest the application of the developed sensor as a point of care device for the diagnosis of leptospirosis.

• Klíčová slova
• AuN/CNF, DNA sensor, Leptospira interrogans, Loa22 gene,
• MeSH
• kovové nanočástice * MeSH
• Leptospira interrogans * genetika   MeSH
• leptospiróza * diagnóza   MeSH
• lidé MeSH
• membránové proteiny MeSH
• zlato MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• membránové proteiny MeSH
• zlato MeSH

From the rediscovery of graphene in 2004, the interest in layered graphene analogs has been exponentially growing through various fields of science. Due to their unique properties, novel two-dimensional family of materials and especially transition metal dichalcogenides are promising for development of advanced materials of unprecedented functions. Progress in 2D materials synthesis paved the way for the studies on their hybridization with other materials to create functional composites, whose electronic, physical or chemical properties can be engineered for special applications. In this review we focused on recent progress in graphene-based and MoS2 hybrid nanostructures. We summarized and discussed various fabrication approaches and mentioned different 2D and 3D structures of composite materials with emphasis on their advances for electroanalytical chemistry. The major part of this review provides a comprehensive overview of the application of graphene-based materials and MoS2 composites in the fields of electrochemical sensors and biosensors.

• Klíčová slova
• 2D materials, bioanalysis, biomarker, carbon, electrode,
• MeSH
• biosenzitivní techniky * MeSH
• chemické jevy MeSH
• disulfidy chemie   MeSH
• elektrochemické techniky * MeSH
• grafit chemie   MeSH
• molybden chemie   MeSH
• nanokompozity chemie   ultrastruktura   MeSH
• nanotechnologie MeSH
• techniky syntetické chemie MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• disulfidy MeSH
• grafit MeSH
• molybden MeSH
• molybdenum disulfide MeSH Prohlížeč