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1.
Small ; 20(6): e2305900, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37786266

RESUMO

Designing photocatalysts with efficient charge transport and abundant active sites for photocatalytic CO2 reduction in pure water is considered a potential approach. Herein, a nickel-phthalocyanine containing Ni-N4 active sites-based conjugated microporous polymer (NiPc-CMP), offering highly dispersed metal active sites, satisfactory CO2 adsorption capability, and excellent light harvesting properties, is engineered as a photocatalyst. By virtue of the covalently bonded bridge, an atomic-scale interface between the NiPc-CMP/Bi2 WO6 Z-scheme heterojunction with strong chemical interactions is obtained. The interface creates directional charge transport highways and retains a high redox potential, thereby enhancing the photoexcited charge carrier separation and photocatalytic efficiency. Consequently, the optimal NiPc-CMP/Bi2 WO6 (NCB-3) achieves efficient photocatalytic CO2 reduction performance in pure water under visible-light irradiation without any sacrificial agent or photosensitizer, affording a CO generation rate of 325.9 µmol g-1 with CO selectivity of 93% in 8 h, outperforming those of Bi2 WO6 and NiPc-CMP, individually. Experimental and theoretical calculations reveal the promotion of interfacial photoinduced electron separation and the role of Ni-N4 active sites in photocatalytic reactions. This study presents a high-performance CMP-based Z-scheme heterojunction with an effective interfacial charge-transfer route and rich metal active sites for photocatalytic CO2 conversion.

2.
Biosensors (Basel) ; 13(11)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37998159

RESUMO

The empty-space-induced depletion region in photoelectrodes severely exacerbates the recombination of electron-hole pairs, thereby reducing the photoelectrochemical (PEC) analytical performance. Herein, the chemical bond that can suppress the potential barrier and overcome the high energy barrier of out-of-plane Ohmic or Schottky contact is introduced into the PEC sensor to eliminate the depletion region and dramatically promote the separation of electron-hole pairs. Specifically, three-dimensional (3D) hierarchically wheatear-like TiO2 (HWT) nanostructures featuring a large surface area to absorb incident light are crafted as the substrate. The facile carbonized strategy is further employed to engineer the Ti-C chemical bond, serving as the touchstone. The average PL lifetime of HWT-C (4.14 ns) is much shorter than that of the 3D HWT (8.57 ns) due to the promoting effect of the chemically bonded structure on carrier separation. Consequently, the 3D HWT-C covalent photoelectrode (600 µA/cm2) exhibits a 3.6-fold increase in photocurrent density compared with the 3D HWT (167 µA/cm2). Ultimately, the model analyte of the tumor marker is detected, and the linear range is 0.02 ng/mL-100 ng/mL with a detection limitation of 0.007 ng/mL. This work provides a basic understanding of chemical bonds in tuning charge separation and insights on strategies for designing high-performance PEC sensors.


Assuntos
Biomarcadores Tumorais , Nanoestruturas , Animais , Elétrons
3.
Anal Chem ; 93(39): 13373-13381, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34553925

RESUMO

In this study, a CRISPR/Cas12a (LbCpf1)-mediated electrochemiluminescence (ECL) paper-based platform on the basis of a three-dimensional (3D) DNA walker was proposed for the ultrasensitive detection of miRNA-141. Initially, 3D-rGO with a tremendous loading space was modified on the paper working electrode (PWE) to construct an excellent conductive substrate and facilitate the growth of AuPd nanoparticles (NPs). Afterward, the AuPd NPs were introduced as the coreaction emitter medium of the 3D-rGO/PWE to provide convenience for the transformation between S2O82- and SO42-, amplifying the ECL emission of g-C3N4 nanosheets (NSs). Meanwhile, with the help of Nt.BsmAI nicking endonuclease, a 3D DNA walker signal amplifier was designed to convert and magnify the target miRNA-141 into a particular trigger sequence, which could act as activator DNA to motivate the trans-acting deoxyribonuclease activity of CRISPR/Cas12a to further achieve efficient annihilation of the ECL signal. Furthermore, the proposed multimechanism-driven biosensor exhibited excellent sensitivity and specificity, with a relatively low detection limit at 0.331 fM (S/N = 3) in the concentration range between 1 fM and 10 nM. Consequently, the designed strategy not only extended the application scope of CRISPR/Cas12a but also devoted a new approach for the clinical diagnosis of modern medicine.


Assuntos
Sistemas CRISPR-Cas , MicroRNAs , Sistemas CRISPR-Cas/genética , DNA/genética
4.
Biosens Bioelectron ; 185: 113250, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915433

RESUMO

Exploring novel photoactive materials with high photoelectric conversion efficiency plays a crucial role in enhancing the analytical performance of paper-based photoelectrochemical (PEC) biosensor. SnO2, which possesses higher photostability and electron mobility, can be regarded as a promising photoactive material. Herein, paper-based one dimensional (1D) domed SnO2 nanotubes (NTs) have been developed with the template-consumption strategy. What's more, their growth mechanism has also been proposed based on the controllable experiments. At first, the paper-based 1D ZnO nanorods (NRs) as the typical amphoteric oxide are prepared and serve as the sacrifice templates which can be etched by the generated alkaline environment during the formation of SnO2. At a certain stage, all the ZnO NRs can be completely etched by controlling the experimental conditions, resulting in the forming of vertically distributed hollow SnO2 NTs. Furthermore, the Sn self-doping strategy is also proposed to suppress the recombination of charge carriers and broaden the light response range by introducing the impurity energy levels. Profiting from such doping strategy, the prominent photocurrent signal is obtained compared with pure paper-based SnO2 NTs. Ultimately, an innovative visible light responsive paper-based Sn-doping SnO2-x NTs are developed and employed as the photoelectrode for the PEC biosensor using the alpha fetoprotein (AFP) as the model analyte. Under the optimal conditions, the ultrasensitive AFP sensing is realized with the linear range and detection limitation of 10 pg mL-1 to 200 ng mL-1 and 3.84 pg mL-1, respectively. This work provides a judiciously strategy for developing novel photoactive materials for paper-based PEC bioanalysis.


Assuntos
Técnicas Biossensoriais , Nanotubos , Luz , Óxidos
5.
ACS Appl Mater Interfaces ; 12(38): 42604-42611, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32852185

RESUMO

A novel photoelectrochemical (PEC) aptasensor was fabricated for DNA detection based on the coupling of cosensitization and peroxidase-like catalytic activity. Specifically, the surfaces of branched-TiO2 nanorods (B-TiO2 NRs) were modified with Cd2+ and S2+ to obtain B-TiO2 NRs/CdS hybrid structures, which were subsequently used as matrices to immobilize hairpin DNA (hDNA) probes. CdTe/TCPP (TCPP = meso-tetra(4-carboxyphenyl)-porphine) used for signal amplification was labeled on the terminal of the hDNA probe. Without the target DNA (tDNA) presence, the immobilized hDNA probe with CdTe/TCPP possessed a hairpin form and was located near the B-TiO2 NRs/CdS electrode surface, forming a cosensitized structure formation and then generating strong photocurrent with H2O2 as the electron donor. During detection, the specific recognition of tDNA by the sensing hDNA probe triggered the formation of the G-quadruplex/hemin DNAzyme, which effectively catalyzed the decomposition of H2O2. Meanwhile, cosensitization disappeared when the hDNA probe hybridized with tDNA, further reducing the photocurrent. With a double-signal amplification strategy, the sensing platform designed in this work demonstrated a linear detection ability in the 0.5 fM-5 nM range with a detection limit equal to 0.14 fM. Notably, through encoding in the base sequences of the hDNA and marking it, a versatile PEC platform could be structured for the detection of various DNA targets, which could promise applications in point-of-care diagnostic fields.


Assuntos
Compostos de Cádmio/química , DNA Catalítico/química , DNA/análise , Hemina/química , Nanocompostos/química , Porfirinas/química , Sulfetos/química , Titânio/química , Biocatálise , Sondas de DNA/química , DNA Catalítico/metabolismo , Eletrodos , Quadruplex G , Hemina/metabolismo , Humanos , Tamanho da Partícula , Propriedades de Superfície
6.
Anal Chem ; 92(10): 6822-6826, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32378879

RESUMO

Exploring efficient luminophores in the electrochemiluminescence (ECL) system is highly desired to pursue a sensitive ECL sensing platform. Herein, the black phosphorus nanosheets (BP NSs) with excellent ECL properties are investigated and serve as the luminophore with the coreactant of peroxydisulfate (S2O82-) solution. Moreover, owing to the overlapping of emission and absorbance spectra, effective resonance energy transfer (RET) is realized between the BP NSs and the introduced Au nanoparticles. In order to achieve the portable and miniaturized developing trends for the paper-based ECL sensing platform, a paper-based perovskite solar cell (PSC) device is designed to act as the power source to replace the commonly utilized expensive and cumbersome electrochemical workstation. Benefiting from that, a PSC driven paper-based constant potential ECL-RET sensing platform is constructed, thereby realizing sensitive microRNAs (miRNAs) detection. What's more, to attain the preferable analytical performance, the duplex-specific nuclease (DSN) is also introduced to assist the target recycling signal amplification strategy. Based on this, highly sensitive detection of miRNA-107 with a range from 0.1 pM to 15 nM is achieved by this designed sensing platform. Most importantly, this work not only pioneers a precedent for developing a high-sensitivity PSC triggered ECL sensing platform but also explores the application prospect of BP nanomaterial in the field of bioanalysis.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Papel , Fósforo/análise , Energia Solar , Compostos de Cálcio/química , Óxidos/química , Titânio/química
7.
Anal Chem ; 92(4): 2902-2906, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32013407

RESUMO

Efficient separation of electron-hole pairs is vitally crucial to enhancing the analytical performance of paper-based photoelectrochemical (PEC) bioanalysis. Herein, a simple but effective strategy is developed to modulate the effective separation of photogenerated electrons and holes via introducing a polar charge carriers-created (PCC) electric field induced by a classical perovskite ferroelectric BaTiO3 (BTO). By inserting it between the n-type WO3 nanoflakes and p-type Cu2O (WO3 nanoflakes/BTO/Cu2O), the photoelectrode is endowed with a renewable PCC electric field, as a sustaining driving force, to guarantee the realization of directional separation of charge carrier (DSCC) strategy in PEC bioanalysis. The enduring PCC electric field can attract the electrons of Cu2O and holes of WO3, respectively, thereby regulating the directional migration of charge carriers and achieving an enhanced PEC photocurrent for the ultrasensitive quantification based on the highly efficient separation of electron-hole pairs. Consequently, with respect to WO3 nanoflakes/Cu2O and WO3 nanoflakes photoelectrode, the polarized WO3 nanoflakes/BTO/Cu2O photoelectrode exhibits 1.7 and 10.9 times higher photocurrent density, respectively. Benefiting from this, the prominent photocurrent density is obtained which is extremely beneficial for enhancing the sensitivity of PEC bioanalysis. Ultimately, the ultrasensitive detection of model prostate specific antigen (PSA) is realized and presents a linear range of 0.1 pg/mL-50 ng/mL with the detection limitation of 0.036 pg/mL. This work provides the basis for understanding the role of the polarized electric field induced by ferroelectric in tuning the charge separation as well as insights on strategies for constructing high-performance paper-based PEC bioanalysis.

8.
ACS Appl Mater Interfaces ; 11(44): 41062-41068, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31597416

RESUMO

A wide-spectrum-responsive paper-based photoelectrochemical (PEC) sensor based on black phosphorus (BP) quantum dots (QDs)-sensitized titanium dioxide (TiO2-BP QDs) for prostate-specific antigen (PSA) detection was presented herein. Carbon nanotubes (CNTs) were first coated on paper to form a flexible conductive paper electrode. TiO2 nanoparticles were then in situ synthesized on the CNTs-modified paper working electrode with direct liquid-phase hydrolysis with normal temperature, shirtsleeve operation, and gentle solution. Meanwhile, BP QDs, derived from two-dimensional BP nanosheets, can harvest light from the ultraviolet to near-infrared region, broaden efficient utilization of light, add a new dimension to BP research, and impel the high expectation on the potentials of QDs. To implement an assay protocol, exciton-plasmon interactions between TiO2-BP QDs and gold nanoparticles were introduced into the PEC sensing platform for high sensitivity detection of the PSA antigen. Under the optimal conditions, this proposed method exhibited a linear response ranging from 0.005 to 50 ng/mL with a detection limit of 1 pg/mL. This sensing protocol offered a promising analytical method with favorable properties of high selectivity, stability, and reproducibility.

9.
Biosens Bioelectron ; 133: 1-7, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30901598

RESUMO

This work reports a microfluidic paper-based photoelectrochemical (µ-PEC) sensing platform for thrombin (TB) detection with electron-transfer tunneling distance regulation (ETTDR) and aptamer target-triggering nicking enzyme signaling amplification (NESA) dual strategies. Specifically, paper-based TiO2 nanosheets (PTNs) were prepared with an efficient hydrothermal process, serving as the direct pathway for the charge carriers transfer. When CeO2-labeled hairpin DNA 3 (HP3) was closely located at the PTNs, the CeO2-PTNs heterostructure was formed, which could great facilitate the photogenerated carries separation of CeO2. In addition, with the aid of aptamer target-triggering NESA strategy, the input TB could be transducted to numerous output target of DNA (tDNA), achieving the goal of desirable signal amplification. In the presence of TB, the output tDNA could be further hybridized with HP3 and unfold its hairpin loop, which forced the CeO2 away from the surface of PTNs and vanished the CeO2-PTNs heterostructure, resulting in the obviously reducing of photocurrent signal. The as-designed sensing platform exhibited a linear range from 0.02 pM to 100 pM with a detection limit of 6.7 fM. Importantly, this µ-PEC sensing platform could not only realize the highly efficient TB detection, but also pave a luciferous way for the detection of other protein in bioanalysis.


Assuntos
Técnicas Biossensoriais , DNA/química , Técnicas Eletroquímicas , Trombina/isolamento & purificação , Aptâmeros de Nucleotídeos/química , Transporte de Elétrons , Elétrons , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Trombina/química
10.
Biosens Bioelectron ; 131: 17-23, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30798248

RESUMO

By controlling target-induced signal quencher release, a label-free and modification-free microfluidic paper based photoelectrochemical analytical device (µ-PAD) for cardiac troponin-I (cTnI) detection was designed for the first time. To achieve it, cellulose paper based single-crystalline three-dimensional aloe like TiO2 arrays (PSATs) were firstly fabricated as the electron transporting material, providing direct pathways for the charge carriers transfer, and subsequently coupled with CdS to form PSATs/CdS heterojunction for extending the solar spectrum response. Meanwhile, positive charged mesoporous silica nanoparticles (PMSNs) were prepared as the nanocarrier to efficient entrap the Cu2+ which could be regarded as signal quencher due to their reaction with CdS to form CuxS. Single stranded DNAs (ssDNAs), which could bind specifically with the target of cTnI, were then introduced to couple with the PMSNs and used as the bio-gate to encapsulate the signal quencher of Cu2+, endowing the functional PMSNs with responsiveness to cTnI. When the cTnI existed, the ssDNAs were dissociated from PMSNs due to the formation of cTnI-ssDNAs complexes, triggering controllable release of the trapped Cu2+, and further decreasing the photocurrent signal caused by the formation of CuxS. Accordingly, the concentration of cTnI could be accurately quantified via the photocurrent, realizing the target-induced modification-free µ-PAD assay. We believe this work could provide an ingenious idea to construct the easy-to-use novel modification-free µ-PAD.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Troponina I/isolamento & purificação , Aloe/química , Compostos de Cádmio/química , Elétrons , Humanos , Limite de Detecção , Titânio/química , Troponina I/química
11.
Adv Mater ; 31(8): e1806596, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30614566

RESUMO

Rutile titanium dioxide (TiO2 ) is a promising photocatalyst due to its high thermodynamic stability and few intragrain defects. However, it has not yet achieved photocatalytic activity comparable to that of anatase TiO2 owing to its higher recombination rate of electron-hole pairs. To effectively separate the electron-hole pairs in rutile TiO2 , a facet heterojunction (FH) structure to prolong the lifetime of the photogenerated electrons is proposed. Ultrathin TiO2 nanosheets with different facets are coated in situ onto TiO2 nanorod (NR) substrates, where FHs are built among the nanosheets as well as between the nanosheets and NR substrates. The as-prepared rutile TiO2 , with an FH structure (FH-TiO2 ), serves as an effective photocatalyst for water splitting. More than 45 and 18 times higher photogenerated current density and H2 production rate, respectively, are obtained compared to those of pure rutile TiO2 NRs. Moreover, FH-TiO2 delivers a 0.566 mmol g-1 h-1 H2 production rate even in pure water. This study offers important insights into the rational design of rutile TiO2 structures for highly efficient photocatalytic reactions.

12.
Anal Chem ; 90(24): 14116-14120, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30421907

RESUMO

A bidirectional modulation of photoinduced charge carrier separation strategy based on TiO2/Bi4NbO8Cl/Co-Pi was proposed in microfluidic paper based photoelectrochemical analytical device (µ-POAD). Perovskite Bi4NbO8Cl with high charge carrier mobility was employed as visible light absorber, sandwiching between electron transporting material (ETM) and hole transporting material (HTM). Paper based TiO2 nanosheet arrays (PTNAs) serve as the ETM to provide a direct pathway for electron transport and Co-Pi works as the HTM to extract holes. Driven by a built-in electric field, the generated electrons of Bi4NbO8Cl are extracted by PTNAs, while holes are drawn toward Co-Pi, achieving efficient carrier separation. Remarkably, it is the first time that the HTM was introduced into µ-POAD to efficiently output holes and enhance the sensitivity. With the aid of ETM and HTM, 2.59 and 14.6 times higher photocurrent density was obtained compared with PTNAs/Bi4NbO8Cl and Bi4NbO8Cl photoelectrode, respectively. Benefiting from this dramatic photocurrent signal, ultrasensitive detection of ß human chorionic gonadotrophin is realized with the linear range of 0.01-3000 IU L-1 and detection limitation of 0.005 IU L-1. This work demonstrates the importance of efficient carrier separation to the sensitivity of µ-POAD and paves the way for developing a high-performance analytical device.

13.
J Mater Chem B ; 6(28): 4697-4703, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32254414

RESUMO

In this study, a single-interface photoelectrochemical (PEC) sensor for detecting two antigens, alpha fetoprotein (AFP) and cancer antigen 153 (CA 153), was achieved based on the heterostructure of branched titanium dioxide nanorods (B-TiO2 NRs)@strontium titanate (SrTiO3) heterostructures. The B-TiO2 NRs@SrTiO3 heterostructure, prepared by a facile hydrothermal method with the feature of enhanced photogenerated charge carrier separation properties, was first employed as a photoactive substrate for anchored analyst. In order to achieve the goal of successfully detecting two biomarkers at a single interface, the two specific enzyme tags ß-galactosidase and acetylcholine esterase linked with a secondary detection antibody were utilized to catalytically hydrolyze p-aminophenyl galactopyranoside and acetylthiocholine to p-aminophenol and thiocholine, respectively. Based on the above enzyme-catalyzed reactions to produce sacrificial electron donors, the photocurrent signals generated from different analytes could be distinguished at a single interface. The results demonstrate that this single-interface PEC sensor not only provides a method for the early detection of AFP and CA 153 but also provides new insight into designing a novel PEC sensor for the detection of two biomarkers with high efficiency and a simple method of operation.

14.
Biosens Bioelectron ; 89(Pt 2): 728-734, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27865108

RESUMO

By incorporating the Prussian Blue (PB) electrochromic display as cathode, a solar-driven photoelectrochemical (PEC) cell was constructed through combining sandwich-structured graphite-like carbon nitride (g-C3N4)-Au-branched-titanium dioxide (B-TiO2) nanorods as photoanode for self-powered hydrogen peroxide (H2O2) sensing, which exhibits both direct photoelectrochemical and electrochromic response. The gold nanoparticles (Au NPs) sandwiched between the B-TiO2 nanorods and the g-C3N4 layer served as electron relay as well as plasmonic photosensitizer to enhance the solar-to-chemical energy conversion efficiency. Owing to the effective disproportionation of H2O2 and specific recognition of mannose on cell surface, concanavalin-A conjugated porous AuPd alloy nanoparticles were introduced as the catalytically active nanolabels promoting generation of hydroxyl radicals (·OH). Based on the cleavage of DNA with the participation of ·OH radicals generated by the decomposition of H2O2 under the catalysis of AuPd alloy result in the disassembly of cancer cells to achieve further signal enhancement. The multiple-signal-output sensing response not only provides a promising strategy for different analytical purposes based on novel stimuli-responsive materials, but also enhances the reliability in the analyte detection.


Assuntos
Técnicas Biossensoriais/instrumentação , Corantes/química , Ferrocianetos/química , Grafite/química , Peróxido de Hidrogênio/análise , Nanotubos/química , Titânio/química , Linhagem Celular Tumoral , Colorimetria/instrumentação , Técnicas Eletroquímicas/instrumentação , Eletrodos , Ouro/química , Humanos , Nanotubos/ultraestrutura , Neoplasias/diagnóstico
15.
Biosens Bioelectron ; 90: 336-342, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27940236

RESUMO

This work described that one-step synthesis three dimensional anatase hierarchically cactus-like TiO2 arrays (AHCT) and their application in constructing a novel photoelectrochemical (PEC) and visualized sensing platform based on molecular imprinting technique, which reports its result with the prussian blue (PB) electrode served as the electrochromic indicator for the detection of glycoprotein (RNase B). The AHCT arrays were perpendicularly grown on FTO substrate with tunable sizes, offering many advantages, such as large contact area, rapid charge electron separation and transport. A possible formation process of the interesting AHCT arrays has been investigated based on time-dependent experiment. In addition, the PEC and visualized sensing platform was constructed based on the molecularly imprinted polymer modified AHCT arrays. Specifically, in the proposed system, the more RNase B being, the more insulating layer was formed on the surface of AHCT arrays that impeded the harvesting of light and electron transfer, resulting in the reduction of photocurrent. When upon light illumination, the photogenerated electrons flow through an external circuit to PB, leading to the reduction of PB to prussian white (PW), which is transparent. The rate of decolourization of PB is proportional to the concentration of RNase B. In this way, a visualized PEC sensing platform that gives its quantitative information could be performed by monitoring the change of color intensity. Under optimal conditions, the protocol possessed a detection range of 0.5pM to 2µM (r=0.997) and the limit of detection was 0.12 pM toward RNase B. Our method eliminates the need for sophisticated instruments and high detection expenses, making it possible to be a reliable alternative in resource-constrained regions.


Assuntos
Técnicas Biossensoriais , Glicoproteínas/isolamento & purificação , Ribonucleases/isolamento & purificação , Titânio/química , Técnicas Eletroquímicas , Glicoproteínas/química , Impressão Molecular , Polímeros/química , Ribonucleases/química
16.
ACS Appl Mater Interfaces ; 8(34): 22238-45, 2016 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-27526617

RESUMO

The performance of organolead halide perovskites based solar cells has been enhanced dramatically due to the morphology control of the perovskite films. In this paper, we present a fast solvent-assisted molecule inserting (S-AMI) strategy to grow high-quality perovskite film, in which the methylammonium iodide/2-propanol (MAI/IPA) solution is spin-coated onto a dimethylformamide (DMF) wetted mixed lead halide (PbX2) precursor film. The DMF can help the inserting of MAI molecules into the PbX2 precursor film and provide a solvent environment to help the grain growth of the perovskite film. The perovskite film grown by the S-AMI approach shows large and well-oriented grains and long carrier lifetime due to the reduced grain boundary. Solar cells constructed with these perovskite films yield an average efficiency over 17% along with a high average fill factor of 80%. Moreover, these unsealed solar cell devices exhibit good stability in an ambient atmosphere.

17.
Biosens Bioelectron ; 83: 327-33, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27135937

RESUMO

In this work, a novel sensing platform based on visible light driven biofuel cell (BFC) has been facilely designed for sensitive detection of prostate-specific antigen (PSA) with the photo-response bioanode, realizing the dual route energy conversion of light energy and chemical energy to electricity. The hierarchical branched TiO2 nanorods (B-TiO2 NRs) decorated with CdS quantum dots (QDs) act as the substrate to confine glucose dehydrogenase (GDH) for the visible light driven glucose oxidation at the bioanode. Three dimensional flowers like hierarchical carbon/gold nanoparticles/bilirubin oxidase (3D FCM/AuNPs/BOD) bioconjugate served as biocatalyst for O2 reduction at the biocathode. With an increase in the concentration of PSA, the amount of BOD labels on biocathode increases, thus leading to the higher current output of the as-proposed visible light driven BFC. Based on this, this sensing platform provide great performance in sensitivity and specificity, increasing linear detection range from 0.3pgmL(-1) to 7µgmL(-1) with a detection limit of 0.1pgmL(-1). Most importantly, our new sensing strategy provided a simple and inexpensive sensing platform for tumor markers detection, suggesting its wide potential applications for clinical diagnostics.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais/métodos , Nanotubos/química , Antígeno Prostático Específico/sangue , Titânio/química , Biomarcadores Tumorais/sangue , Técnicas Biossensoriais/instrumentação , Compostos de Cádmio/química , Eletrodos , Enzimas Imobilizadas/metabolismo , Glucose 1-Desidrogenase/metabolismo , Humanos , Luz , Limite de Detecção , Nanotubos/ultraestrutura , Compostos de Selênio/química
18.
Biosens Bioelectron ; 85: 205-211, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27179135

RESUMO

A platelike tungsten trioxide (WO3) sensitized with CdS quantum dots (QDs) heterojunction is developed for solar-driven, real-time, and selective photoelectrochemical (PEC) sensing of H2O2 in the living cells. The structure is synthesized by hydrothermally growing platelike WO3 on fluorine doped tin oxide (FTO) and subsequently sensitized with CdS QDs. The as-prepared WO3-CdS QDs heterojunction achieve significant photocurrent enhancement, which is remarkably beneficial for light absorption and charge carrier separation. Based on the enzymatic etching of CdS QDs enables the activation of quenching the charge transfer efficiency, thus leading to sensitive PEC recording of H2O2 level in buffer and cellular environments. The results indicated that the proposed method will pave the way for the development of excellent PEC sensing platform with the quantum dot sensitization. This study could also provide a new train of thought on designing of self-operating photoanode in PEC sensing, promoting the application of semiconductor nanomaterials in photoelectrochemistry.


Assuntos
Técnicas Biossensoriais/instrumentação , Compostos de Cádmio/química , Técnicas Eletroquímicas/instrumentação , Peróxido de Hidrogênio/análise , Óxidos/química , Pontos Quânticos/química , Sulfetos/química , Tungstênio/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Peroxidase do Rábano Silvestre/química , Humanos , Limite de Detecção , Células MCF-7 , Pontos Quânticos/ultraestrutura , Transdutores
19.
Chem Commun (Camb) ; 51(46): 9527-30, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-25969846

RESUMO

A dual functional analytical device performing both energy conversion and electric energy storage based on biofuel cells to implement self-powered point-of-care testing was developed based on a piece of Ti foil.


Assuntos
Fontes de Energia Bioelétrica , Testes Imediatos , Antígeno Prostático Específico/sangue , Cobre/química , Eletrodos , Ouro/química , Humanos , Microscopia Eletrônica de Varredura , Nanotubos/química , Nanotubos/ultraestrutura , Titânio/química
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