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1.
J Nanosci Nanotechnol ; 20(11): 6975-6979, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32604544

RESUMO

Graphene oxide (GO) is a well-known two-dimensional nanomaterial with broad applications in various fields. In particular, the functional groups of GO has demonstrated significance in the molecular binding interactions. GO is normally coated on a solid surface as it is difficult to handle due to its nano-scaled size. Therefore, chemical properties of surface-coated GO depend on the morphological structure of GO on the surface and the operating conditions during the coating process. Isolation of bacteria from environmental samples such as river and pond water is important for increasing the analytical sensitivity of sensor devices. The main issue in isolation of bacteria from an environmental sample is adsorption capacity per unit time. However, increasing the velocity of water sample to elevate the process rate induces high shear stress on the surface, such that the bacteria adsorption rate on the surface is reduced. In this study, we investigated the morphological and chemical properties of sonicated GO and GO-coated surface by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The sonicated GO-coated beads were successfully used for concentrating bacteria from a large-volume sample as opposed to the conventional methods. It can be concluded that, GO-coated surfaces are prospective platforms for concentrating bacteria from various samples and play a major role in reducing the concentration time.

2.
Biomaterials ; 252: 120106, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32417651

RESUMO

It is known that tumor antigens could induce obvious anti-tumor immune responses for efficient cancer immunotherapy when combined with checkpoint blockade. However, the amount of tumor antigens is often limited due to the suppressive tumor microenvironment (TME). Here, a new type of nanomaterial was developed to improve tumor treatment by the combined action of starving therapy/photodynamic therapy (PDT)/photothermal therapy (PTT) and checkpoint-blockade immunotherapy. In detail, the immunoadjuvant nanoagents (γ-PGA@GOx@Mn,Cu-CDs) were fabricated by integrating the gamma-glutamyl transferase (GGT) enzyme-induced cellular uptake polymer-poly (γ-glutamic acid) (γ-PGA), a glucose-metabolic reaction agent - glucose oxidase (GOx), Mn,Cu-doped carbon dots (CDs) as photosensitizer and self-supplied oxygenator nanodots. γ-PGA@GOx@Mn,Cu-CDs nanoparticles (NPs) showed long retention time at the tumor acidic microenvironment and could further target cancer cells. The NPs also displayed both photothermal and photodynamic effects under laser irradiation at 730 nm. Interestingly, the endogenous generation of hydrogen peroxide (H2O2) caused by the nanoreactors could significantly relieve tumor hypoxia and further enhance in vivo PDT. By synergistically combining the NPs-based starving-like therapy/PDT/PTT and check-point-blockade therapy, the treatment efficiency was significantly improved. More importantly, the systematic antitumor immune response would eliminate non-irradiated tumors as well, which is promising for metastasis inhibition.

3.
Biosens Bioelectron ; 159: 112208, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32364932

RESUMO

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). The limit of detection of the proposed biosensor for microRNA-21 and microRNA-141 was respectively 204 aM and 138 aM with a wide linear range from 500 aM to 50 nM. As a proof of concept, this newly-developed strategy was coupled with a 96-well adaptive sensing device to successfully profile three cancer plasma samples based on their altered oncomiR abundances.

4.
Mikrochim Acta ; 187(5): 277, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32314063

RESUMO

MXene nanosheets of type Ti3C2Tx were modified with ß-hydroxybutyrate dehydrogenase and then used as a biosensor for amperometric sensing of ß-hydroxybutyrate. The MXene and the nanocomposite were characterized by X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The MXene has a layered structure and proved to be an excellent immobilization matrix providing good compatibility with the enzyme ß-hydroxybutyrate dehydrogenase. The MXene-based biosensor, best operated at a potential of - 0.35 V (vs. Ag/AgCl), displays a wide linear range (0.36 to 17.9 mM), a sensitivity of 0.480 µA mM-1 cm-2, and a low detection limit (45 µM). The biosensor was successfully applied to the determination of ß-hydroxybutyrate in (spiked) real serum samples. Graphical abstract Schematic representation of the synthesis and decoration of Mxene 2D sheets with ß-hydroxybutyrate dehydrogenase for the amperometric determination of ß-hydroxybutyric acid.

5.
Micromachines (Basel) ; 10(10)2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31575012

RESUMO

Effective cancer treatment requires early detection and monitoring the development progress in a simple and affordable manner. Point-of care (POC) screening can provide a portable and inexpensive tool for the end-users to conveniently operate test and screen their health conditions without the necessity of special skills. Electrochemical methods hold great potential for clinical analysis of variety of chemicals and substances as well as cancer biomarkers due to their low cost, high sensitivity, multiplex detection ability, and miniaturization aptitude. Advances in two-dimensional (2D) material-based electrochemical biosensors/sensors are accelerating the performance of conventional devices toward more practical approaches. Here, recent trends in the development of 2D material-based electrochemical biosensors/sensors, as the next generation of POC cancer screening tools, are summarized. Three cancer biomarker categories, including proteins, nucleic acids, and some small molecules, will be considered. Various 2D materials will be introduced and their biomedical applications and electrochemical properties will be given. The role of 2D materials in improving the performance of electrochemical sensing mechanisms as well as the pros and cons of current sensors as the prospective devices for POC screening will be emphasized. Finally, the future scopes of implementing 2D materials in electrochemical POC cancer diagnostics for the clinical translation will be discussed.

6.
Biosens Bioelectron ; 141: 111468, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31279178

RESUMO

Development of a very sensitive biosensor is accompanied with an inevitable shrinkage in the linear detection range. Here, we developed an electrochemical biosensor with a novel methodology to detect microRNA-21 (miR21) at an ultralow level and broad linear detection range. A three-way junction RNA structure was designed harboring (i) a methylene blue (MB)-modified hairpin structure at its one leg to function as the sensing moiety and (ii) the other two legs to be further hybridized with barcode gold nanoparticles (MB/barG) as the signal amplifiers. Addition of target miR21 resulted in opening the hairpin moiety and subsequent hybridization with DNA-modified gold nanoflower/platinum electrode (GNF@Pt) to form the MB-3 sensor. Inspired by the relay-race run, to extend the dynamic detection range and increase the sensitivity of the biosensor, MB/barG was added to form the second detection modality (MBG-3). The combined sensor required very low sample volume (4 µL) and could identify 135 aM or 324 molecules of miR21 with the ability to operate within a wide linear range from 1 µM down to 500 aM. The fabricated GNF@Pt showed a remarkable conductivity compared with the gold nanoparticle-modified electrode. Addition of MB/barG boosted the electrochemical signal of the MB by almost 230 times. Moreover, a new protocol was introduced by the authors to increase the efficiency of microRNA extraction from the total serum. Possessing a sound selectivity and specificity towards single base-pair mutations, the developed biosensor could profile cancer development stages of two patient serums.


Assuntos
Técnicas Biossensoriais/instrumentação , Ouro/química , Nanopartículas Metálicas/química , MicroRNAs/sangue , Técnicas Eletroquímicas/instrumentação , Eletrodos , Desenho de Equipamento , Humanos , Limite de Detecção , Hibridização de Ácido Nucleico
7.
Anal Chem ; 91(9): 5841-5849, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30938982

RESUMO

Infectious pancreatic necrosis virus (IPNV) has been identified as a viral pathogen for many fish diseases that have become a huge hurdle for the growing fishing industry. Thus, in this work, we report a label-free impedance biosensor to quantify IPNV in real fish samples at point-of-care (POC) level. High specificity IPNV sensor with a detection limit of 2.69 TCID50/mL was achieved by conjugating IPNV antibodies to portable Au disk electrode chips using human heavy chain apoferritin (H-AFN) nanoprobes as a binding agent. H-AFN probes were bioengineered through PCR by incorporating pET-28b(+) resulting in 24 subunits of 6 × his-tag and protein-G units on its outer surface to increase the sensitivity of the IPNV detection. The biosensor surface modifications were characterized by differential pulse voltammetry (DPV) and EIS methods for each modification step. The proposed nanoprobe based sensor showed three-fold enhancement in charge transfer resistance toward IPNV detection in comparison with the traditional linker approach when measured in a group of similar virus molecules. The portable sensor exhibited a linear range of 100-10000 TCID50/mL and sensitivity of 5.40 × 10-4 TCID50/mL in real-fish samples. The performance of the proposed IPNV sensor was fully validated using an enzyme-linked immunosorbent assay (ELISA) technique with a sensitivity of 3.02 × 10-4 TCID50/mL. Results from H-AFN nanoprobe based IPNV sensor indicated high selectivity, sensitivity, and stability could be a promising platform for the detection of similar fish viruses and other biological molecules of interest.

8.
Mater Sci Eng C Mater Biol Appl ; 99: 511-519, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889726

RESUMO

Avian influenza virus (AIV) is one of the most harmful pathogens to living things due to its fast infection, various mutations, and dangerous symptoms. In this study, we fabricated a label-free AIV H5N1 biosensor composed of multi-functional DNA structure on a porous Au nanoparticles (pAuNPs) fabricated electrode using the electrochemical (EC) technique. As a multi-functional bioprobe, the DNA 3 way-junction (3WJ) was introduced. Each fragment of DNA 3WJ was rolled to recognition part (hemagglutinin (HA) protein detection aptamer), EC signal generation part (horseradish peroxidase (HRP)-mimicked DNAzyme), and immobilization part (Thiol group). Each fragment was assembled in order to form the DNA 3WJ for AI detection and the assembled structure was confirmed by native-tris boric acid magnesium polyacrylamide gel electrophoresis (TBM-PAGE). Moreover, in order to increase the electrochemical signal sensitivity, pAuNPs were synthesized. The property of pAuNPs was investigated by field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), Ultraviolet-visible (UV-VIS) spectroscopy and zeta potential analysis. The DNA 3WJ on pAuNPs-modified Au electrode was then prepared using the layer-by-layer (LbL) assembly method. FE-SEM and atomic force microscopy (AFM) were used to investigate the surface morphology. Cyclic voltammetry (CV) was carried out to confirm the HA protein binding to DNA 3WJ-modified electrode. Moreover, The HA protein can be detected 1 pM in HEPES solution and 1 pM in diluted-chicken serum, respectively. The present study showed label-free, simple fabrication, and easy-to-tailor detection elements for AIV. The present biosensor can be a powerful candidate for various virus detection platforms.


Assuntos
Técnicas Biossensoriais/métodos , Galinhas/sangue , Galinhas/virologia , DNA/química , Técnicas Eletroquímicas/métodos , Ouro/química , Virus da Influenza A Subtipo H5N1/fisiologia , Nanopartículas Metálicas/química , Animais , Nanopartículas Metálicas/ultraestrutura , Oxirredução , Porosidade , Propriedades de Superfície
9.
ACS Appl Mater Interfaces ; 11(9): 8779-8788, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30714374

RESUMO

Nanoparticle-based cell differentiation therapy has attracted increasing research interest as it is a promising substitute for conventional cancer treatment methods. Here, the topological insulator bismuth selenide nanoparticle (Bi2Se3 NP) was core-shelled with silver (Ag@Bi2Se3) to represent remarkable biocompatibility and plasmonic features (ca. 2.3 times higher than those of Ag nanoparticle). Moreover, a newly developed RNA three-way junction (3WJ) structure was designed for the quad-functionalization of any type of nanoparticle and surface. One leg of the 3WJ was attached to the Ag@Bi2Se3, and the other leg harbored a cell-penetrating RNA and a florescence tag. The third leg was designed to inhibit micro-RNA-17 (miR-17) and to further release retinoic acid (RA). A new drug delivery mechanism was developed for the slow release of RA inside the cytosol based on the prerequisite inhibition of miR-17 using a strand displacement strategy. In this paper, we report a simple methodology for resolving the hydrophobicity challenges of RA by its conjugation with a RNA strand (RA/R) through a stimulus-responsive cross-linker. The developed nanobiohybrid material could fully differentiate SH-SY5Y cancer cells into neurons and stop their growth in 6 days without requiring sequential treatments which has not been reported yet. Using a surface-enhanced Raman spectroscopy technique, the RA delivery and the cell differentiation process were monitored nondestructively in real time. The fabricated nanobiohybrid material could open the new horizons in the fabrication of different diagnostic/therapeutic agents.


Assuntos
Nanopartículas Metálicas/química , MicroRNAs/metabolismo , Compostos Organosselênicos/química , Prata/química , Tretinoína/química , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Portadores de Fármacos/química , Endocitose , Humanos , MicroRNAs/antagonistas & inibidores , Microscopia Confocal , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Oligonucleotídeos/química , Povidona/química , Análise Espectral Raman , Tretinoína/metabolismo , Tretinoína/farmacologia
10.
Adv Exp Med Biol ; 1064: 263-296, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30471039

RESUMO

The field of bioelectronics has paved the way for the development of biochips, biomedical devices, biosensors and biocomputation devices. Various biosensors and biomedical devices have been developed to commercialize laboratory products and transform them into industry products in the clinical, pharmaceutical, environmental fields. Recently, the electrochemical bioelectronic devices that mimicked the functionality of living organisms in nature were applied to the use of bioelectronics device and biosensors. In particular, the electrochemical-based bioelectronic devices and biosensors composed of biomolecule-nanoparticle hybrids have been proposed to generate new functionality as alternatives to silicon-based electronic computation devices, such as information storage, process, computations and detection. In this chapter, we described the recent progress of bioelectronic devices and biosensors based on biomaterial-nanomaterial hybrid.


Assuntos
Materiais Biocompatíveis , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas , Nanopartículas
11.
Small ; 14(38): e1802934, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30141567

RESUMO

For the first time, topological insulator bismuth selenide nanoparticles (Bi2 Se3 NP) are core-shelled with gold (Au@Bi2 Se3 ) i) to represent considerably small-sized (11 nm) plasmonic nanoparticles, enabling accurate bioimaging in the near-infrared region; ii) to substantially improve Bi2 Se3 biocompatibility, iii) water dispersibility, and iv) surface functionalization capability through straightforward gold-thiol interaction. The Au@Bi2 Se3 is subsequently functionalized for v) effective targeting of SH-SY5Y cancer cells, vi) disrupting the endosome/lysosome membrane, vii) traceable delivery of antagomiR-152 and further synergetic oncomiR knockdown and photothermal therapy (PTT). Unprecedentedly, it is observed that the Au shell thickness has a significant impact on evoking the exotic plasmonic features of Bi2 Se3 . The Au@Bi2 Se3 possesses a high photothermal conversion efficiency (35.5%) and a remarkable surface plasmonic effect (both properties are approximately twofold higher than those of 50 nm Au nanoparticles). In contrast to the siRNA/miRNA delivery methods, the antagomiR delivery is based on strand displacement, in which the antagomiR-152 is displaced by oncomiR-152 followed by a surface-enhanced Raman spectroscopy signal drop. This enables both cancer cell diagnosis and in vitro real-time monitoring of the antagomiR release. This selective PTT nanoparticle can also efficiently target solid tumors and undergo in vivo PTT, indicating its potential clinical applications.


Assuntos
Antagomirs/química , Ouro/química , Nanopartículas Metálicas/química , Compostos Organosselênicos/química , Fototerapia/métodos , MicroRNAs/genética , RNA Interferente Pequeno/genética , Nanomedicina Teranóstica/métodos
12.
Small ; 14(16): e1703970, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29573539

RESUMO

A newly developed electrochemical biosensor composed of a topological insulator (TI) and metallic DNA (mDNA) is fabricated. The bismuth selenide nanoparticle (Bi2 Se3 NP) is synthesized and sandwiched between the gold electrode and another Au-deposited thin layer (Bi2 Se3 @Au). Then, eight-silver-ion mediated double-stranded DNA (mDNA) is immobilized onto the substrate (Bi2 Se3 @Au-mDNA) for the further detection of hydrogen peroxide. The Bi2 Se3 NP acts as the electrochemical-signal booster, while unprecedentedly its encapsulation by the Au thin layer keeps the TI surface states protected, improves its electrochemical-signal stability and provides an excellent platform for the subsequent covalent immobilization of the mDNA through Au-thiol interaction. Electrochemical results show that the fabricated biosensor represents much higher Ag+ redox current (≈10 times) than those electrodes prepared without Bi2 Se3 @Au. The characterization of the Bi2 Se3 @Au-mDNA film is confirmed by atomic force microscopy, scanning tunneling microscopy, and cyclic voltammetry. The proposed biosensor shows a dynamic range of 00.10 × 10-6 m to 27.30 × 10-6 m, very low detection limit (10 × 10-9 m), unique current response (1.6 s), sound H2 O2 recovery in serum, and substantial capability to classify two breast cancer subtypes (MCF-7 and MDA-MB-231) based on their difference in the H2 O2 generation, offering potential applications in the biomedicine and pharmacology fields.


Assuntos
Técnicas Biossensoriais/métodos , Neoplasias da Mama/metabolismo , DNA/química , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/metabolismo , Prata/química , Linhagem Celular Tumoral , Feminino , Ouro/química , Humanos , Células MCF-7 , Nanopartículas Metálicas/química
13.
J Biotechnol ; 274: 40-46, 2018 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-29588181

RESUMO

We fabricated a microRNA biosensor using the combination of surface enhanced Raman spectroscopy (SERS) and electrochemical (EC) techniques. For the first time, the weaknesses of each techniques for microRNA detection was compensated by the other ones to give rise to the specific and wide-range detection of miR-155. A single stranded 3' methylene blue (MB) and 5' thiol-modified RNA (MB-ssRNA-SH) was designed to detect the target miR-155 and immobilized onto the gold nanoparticle-modified ITO (ITO/GNP). Upon the invasion of target strand, the double-stranded RNA transformed rapidly to an upright structure resulting in a notable decrease in SERS and redox signals of the MB. For the first time, by combination of SERS and EC techniques in a single platform we extended the dynamic range of both techniques from 10 pM to 450 nM (SERS: 10 pM-5 nM and EC: 5 nM-450 nM). As well, the SERS technique improved the detection limit of the EC method from 100 pM to 100 fM, while the EC method covered single-mismatch detection which was the SERS deficiency. The fabricated single-step biosensor possessing a good capability of miRNA detection in human serum, could be employed throughout the broad ranges of biomedical and bioelectronics applications.


Assuntos
Técnicas Biossensoriais/métodos , Ouro/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Limite de Detecção , MicroRNAs/química , Conformação de Ácido Nucleico , Análise Espectral Raman/métodos
14.
Colloids Surf B Biointerfaces ; 159: 729-736, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28886511

RESUMO

Nitric oxide (NO) is one of the most important molecules in living things due to its role as a signaling molecule in influencing pathological and physiological mechanisms including neurotransmission. In this study, the electrochemical biosensor based on the amine-modified molybdenum disulfide nanoparticles (MoS2), graphene oxide (GO) and myoglobin (Mb) hybrid material (amine-modified MoS2/GO/Mb hybrid) is developed to achieve the accurate detection of NO with electrochemical signal improvement. For the first time, the synthesis of MoS2 accompanying the amine-modification of the surface of MoS2 is done to hybridize with GO efficiently through the short linkage. After the amine-modification of MoS2, it is enclosed with GO directly (amine-modified MoS2/GO). Then, Mb which can induce the reduction of NO is immobilized on the amine-modified MoS2/GO to fabricate the amine-modified MoS2/GO/Mb hybrid for NO detection. The prepared hybrid shows the signal improved redox properties relative to the result of the electrode prepared without hybrid. Furthermore, upon addition of NO, the electrode prepared with hybrid shows the improved amperometric response compared with that of the electrode without hybrid. This amine-modified MoS2/GO/Mb hybrid can be used in the development of the biosensor platform accompanying the electrochemical signal improvement and accurate detection of target materials.


Assuntos
Técnicas Biossensoriais/métodos , Grafite/química , Mioglobina/química , Óxido Nítrico/química , Óxidos/química
15.
Biosens Bioelectron ; 98: 292-298, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28697440

RESUMO

Several challenges remained to fabricate a molecular-level nucleic acid biosensor such as surface immobilization control, single mismatch detection and low current response. To overcome those issues, for the first time, authors presented a novel parallel structural dsDNA/recombinant azurin (PSD/rAzu) hybrid structure for the general nucleic acid detection. The PSD was designed and introduced by the optimized 8 Ag+ ions to have greater conductivity than the canonical dsDNA, and conjugated with rAzu to develop a general platform for electrochemical detection of miRNAs and viral DNAs with high reproducibility and ultra-sensitivity towards single base pair mutation. Thanks to the bifunctional rAzu as the selective spacer and electrochemical signal mediator, in the presence of the target strand, the imperfect PSD switched rapidly to the upright position where the Ag+ ions intercalated between C-C mismatches of dsDNAs at the top of each structure brought further from the electrode surface resulting in a significant electrochemical signal drop of the Ag+ ions. The charge transfer (CT) mechanism across the hybrid structure was simply clarified on the basis of the redox potential location of the species. The electrical conductivity of DNAs were measured using scanning tunneling spectroscopy (STS) at the molecular scale and cyclic voltammetry (CV) technique based on the reduction of Ag+ ion. The proposed PSD/rAzu hybrid structure with a great capability of single mutation recognition and miRNA expression level profiling in cancer cells holds a very promising platform to be studied for further development of various kinds of nanoscale biosensors, bioelectronic devices.


Assuntos
Azurina/química , Técnicas Biossensoriais , DNA/isolamento & purificação , Técnicas Eletroquímicas , DNA/química
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