- Klíčová slova
- elektronická kůže,
- MeSH
- biosenzitivní techniky * přístrojové vybavení MeSH
- lidé MeSH
- monitorování fyziologických funkcí * metody přístrojové vybavení MeSH
- nositelná elektronika MeSH
- povrchové vlastnosti MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- novinové články MeSH
- zprávy MeSH
We propose a label-free biosensor concept based on the charge state manipulation of nitrogen-vacancy (NV) quantum color centers in diamond, combined with an electrochemical microfluidic flow cell sensor, constructed on boron-doped diamond. This device can be set at a defined electrochemical potential, locking onto the particular chemical reaction, whilst the NV center provides the sensing function. The NV charge state occupation is initially prepared by applying a bias voltage on a gate electrode and then subsequently altered by exposure to detected charged molecules. We demonstrate the functionality of the device by performing label-free optical detection of DNA molecules. In this experiment, a monolayer of strongly cationic charged polymer polyethylenimine is used to shift the charge state of near surface NV centers from negatively charged NV- to neutral NV0 or dark positively charged NV+. Immobilization of negatively charged DNA molecules on the surface of the sensor restores the NV centers charge state back to the negatively charged NV-, which is detected using confocal photoluminescence microscopy. Biochemical reactions in the microfluidic channel are characterized by electrochemical impedance spectroscopy. The use of the developed electrochemical device can also be extended to nuclear magnetic resonance spin sensing.
A sensitive and specific approach was developed for the determination of Haemophilus influenza using DNA based bio-assay. In this study, citrate capped silver nanoparticle was synthesized and employed for bioconjugation with pDNA toward target sequences detection. In this study, synthesized probe (SH-5'-AAT TTT CCA ACT TTT TCA CCT GCA T-3') of Haemophilus influenza was detected with great sensitivity and selectivity after hybridization with cDNA (5'-ATG CAG GTG AAA AAG TTG GAA AAT T-3'). Regarding to the obtained results, the low limit of quantification (LLOQ) of DNA sample was 1 ZM using 15 μL of probe and 200 μL of Cit/AgNPs. According to ultra-sensitivity of the fabricated optical DNA-based bio-assay, it has potential for bacterial determination both in clinical and environmental specimens. To evaluate the selectivity of developed DNA based biosensor, three mismatch sequences were applied. Finally, the designed genosensor is a significant diagnostic strategy for detection of Haemophilus influenza with great selectivity.
- MeSH
- biosenzitivní techniky přístrojové vybavení metody MeSH
- biotest MeSH
- DNA bakterií analýza genetika MeSH
- DNA sondy chemie genetika MeSH
- Haemophilus influenzae genetika izolace a purifikace MeSH
- hybridizace nukleových kyselin MeSH
- kovové nanočástice chemie MeSH
- kyselina citronová chemie MeSH
- lidé MeSH
- limita detekce MeSH
- senzitivita a specificita MeSH
- stříbro chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
This paper reports a simple electrochemical strategy for the determination of microRNAs (miRNAs) using a commercial His-Tag-Zinc finger protein (His-Tag-ZFP) that binds preferably (but non-sequence specifically) RNA hybrids over ssRNAs, ssDNAs, and dsDNAs. The strategy involves the use of magnetic beads (His-Tag-Isolation-MBs) as solid support to capture the conjugate formed in homogenous solution between His-Tag-ZFP and the dsRNA homohybrid formed between the target miRNA (miR-21 selected as a model) and a biotinylated synthetic complementary RNA detector probe (b-RNA-Dp) further conjugated with a streptavidin-horseradish peroxidase (Strep-HRP) conjugate. The electrochemical detection is carried out by amperometry at disposable screen-printed carbon electrodes (SPCEs) (- 0.20 V vs Ag pseudo-reference electrode) upon magnetic capture of the resultant magnetic bioconjugates and H2O2 addition in the presence of hydroquinone (HQ). The as-prepared biosensor exhibits a dynamic concentration range from 3.0 to 100 nM and a detection limit (LOD) of 0.91 nM for miR-21 in just ~ 2 h. An acceptable discrimination was achieved between the target miRNA and other non-target nucleic acids (ssDNA, dsDNA, ssRNA, DNA-RNA, miR-122, miR-205, and single central- or terminal-base mismatched sequences). The biosensor was applied to the analysis of miR-21 from total RNA (RNAt) extracted from epithelial non-tumorigenic and adenocarcinoma breast cells without target amplification, pre-concentration, or reverse transcription steps. The versatility of the methodology due to the ZFP's non-sequence-specific binding behavior makes it easily extendable to determine any target RNA only by modifying the biotinylated detector probe.
Our recent experience of the COVID-19 pandemic has highlighted the importance of easy-to-use, quick, cheap, sensitive and selective detection of virus pathogens for the efficient monitoring and treatment of virus diseases. Early detection of viruses provides essential information about possible efficient and targeted treatments, prolongs the therapeutic window and hence reduces morbidity. Graphene is a lightweight, chemically stable and conductive material that can be successfully utilized for the detection of various virus strains. The sensitivity and selectivity of graphene can be enhanced by its functionalization or combination with other materials. Introducing suitable functional groups and/or counterparts in the hybrid structure enables tuning of the optical and electrical properties, which is particularly attractive for rapid and easy-to-use virus detection. In this review, we cover all the different types of graphene-based sensors available for virus detection, including, e.g., photoluminescence and colorimetric sensors, and surface plasmon resonance biosensors. Various strategies of electrochemical detection of viruses based on, e.g., DNA hybridization or antigen-antibody interactions, are also discussed. We summarize the current state-of-the-art applications of graphene-based systems for sensing a variety of viruses, e.g., SARS-CoV-2, influenza, dengue fever, hepatitis C virus, HIV, rotavirus and Zika virus. General principles, mechanisms of action, advantages and drawbacks are presented to provide useful information for the further development and construction of advanced virus biosensors. We highlight that the unique and tunable physicochemical properties of graphene-based nanomaterials make them ideal candidates for engineering and miniaturization of biosensors.
- MeSH
- Betacoronavirus genetika izolace a purifikace patogenita MeSH
- biosenzitivní techniky * přístrojové vybavení metody trendy MeSH
- design vybavení MeSH
- DNA virů analýza genetika MeSH
- elektrochemické techniky MeSH
- grafit * chemie MeSH
- hybridizace nukleových kyselin MeSH
- klinické laboratorní techniky * přístrojové vybavení metody statistika a číselné údaje MeSH
- kolorimetrie MeSH
- koronavirové infekce diagnóza epidemiologie virologie MeSH
- kvantové tečky chemie MeSH
- lidé MeSH
- luminiscence MeSH
- nanostruktury chemie MeSH
- pandemie MeSH
- povrchová plasmonová rezonance MeSH
- Ramanova spektroskopie MeSH
- reakce antigenu s protilátkou MeSH
- virologie metody MeSH
- virová pneumonie diagnóza epidemiologie virologie MeSH
- viry genetika izolace a purifikace patogenita MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The design and application of an inkjet-printed electrochemically reduced graphene oxide microelectrode for HT-2 mycotoxin immunoenzymatic biosensing is reported. A water-based graphene oxide ink was first formulated and single-drop line working microelectrodes were inkjet-printed onto poly(ethylene 2,6-naphthalate) substrates, with dimensions of 78 μm in width and 30 nm in height after solvent evaporation. The printed graphene oxide microelectrodes were electrochemically reduced and characterized by Raman and X-ray photoelectron spectroscopies in addition to microscopies. Through optimization of the electrochemical reduction parameters, differential pulse voltammetry were performed to examine the sensing of 1-naphthol (1-N), where it was revealed that reduction times had significant effects on electrode performance. The developed microelectrodes were then used as an immunoenzymatic biosensor for the detection of HT-2 mycotoxin based on carbodiimide linking of the microelectrode surface and HT-2 toxin antigen binding fragment of antibody (anti-HT2 (10) Fab). The HT-2 toxin and anti-HT2 (10) Fab reaction was reported by anti-HT2 immune complex single-chain variable fragment of antibody fused with alkaline phosphatase (anti-IC-HT2 scFv-ALP) which is able to produce an electroactive reporter - 1-N. The biosensor showed detection limit of 1.6 ng ∙ mL-1 and a linear dynamic range of 6.3 - 100.0 ng ∙ mL-1 within a 5 min incubation with 1-naphthyl phosphate (1-NP) substrate.
- MeSH
- biosenzitivní techniky přístrojové vybavení MeSH
- design vybavení MeSH
- elektrochemické techniky přístrojové vybavení MeSH
- grafit chemie MeSH
- imobilizační protilátky chemie MeSH
- imunoenzymatické techniky přístrojové vybavení MeSH
- mikroelektrody MeSH
- oxidace-redukce MeSH
- reagenční papírky analýza MeSH
- T-2 toxin analogy a deriváty analýza MeSH
- Publikační typ
- časopisecké články MeSH
The gradual acidification of the secretory pathway is conserved and extremely important for eukaryotic cells, but until now there was no pH sensor available to monitor the pH of the early Golgi apparatus in Saccharomyces cerevisiae. Therefore, we developed a pHluorin-based sensor for in vivo measurements in the lumen of the Golgi. By using this new tool we show that the cis- and medial-Golgi pH is equal to 6.6-6.7 in wild type cells during exponential phase. As expected, V-ATPase inactivation results in a near neutral Golgi pH. We also uncover that surprisingly Vph1p isoform of the V-ATPase is prevalent to Stv1p for Golgi acidification. Additionally, we observe that during changes of the cytosolic pH, the Golgi pH is kept relatively stable, mainly thanks to the V-ATPase. Eventually, this new probe will allow to better understand the mechanisms involved in the acidification and the pH control within the secretory pathway.
- MeSH
- biosenzitivní techniky přístrojové vybavení MeSH
- chemické inženýrství MeSH
- Golgiho aparát chemie MeSH
- izoenzymy chemie MeSH
- koncentrace vodíkových iontů MeSH
- Saccharomyces cerevisiae - proteiny chemie MeSH
- Saccharomyces cerevisiae chemie enzymologie MeSH
- vakuolární protonové ATPasy chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The light-driven splitting of water to oxygen (O2) is catalyzed by a protein-bound tetra-manganese penta-oxygen calcium (Mn4O5Ca) cluster in Photosystem II. In the current study, we used a large-scale integration (LSI)-based amperometric sensor array system, designated Bio-LSI, to perform two-dimensional imaging of light-induced O2 evolution from spinach leaves. The employed Bio-LSI chip consists of 400 sensor electrodes with a pitch of 250 μm for fast electrochemical imaging. Spinach leaves were illuminated to varying intensities of white light (400-700 nm) which induced oxygen evolution and subsequent electrochemical images were collected using the Bio-LSI chip. Bio-LSI images clearly showed the dose-dependent effects of the light-induced oxygen release from spinach leaves which was then significantly suppressed in the presence of urea-type herbicide 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). Our results clearly suggest that light-induced oxygen evolution can be monitored using the chip and suggesting that the Bio-LSI is a promising tool for real-time imaging. To the best of our knowledge, this report is the first to describe electrochemical imaging of light-induced O2 evolution using LSI-based amperometric sensors in plants.
