Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 4.806
1.
Microb Cell Fact ; 23(1): 140, 2024 May 17.
Article En | MEDLINE | ID: mdl-38760827

BACKGROUND: Quantum Dots (QDs) are fluorescent nanoparticles with exceptional optical and optoelectronic properties, finding widespread utility in diverse industrial applications. Presently, chemically synthesized QDs are employed in solar cells, bioimaging, and various technological domains. However, many applications demand QDs with prolonged lifespans under conditions of high-energy radiation. Over the past decade, microbial biosynthesis of nanomaterials has emerged as a sustainable and cost-effective process. In this context, the utilization of extremophile microorganisms for synthesizing QDs with unique properties has recently been reported. RESULTS: In this study, UV-resistant bacteria were isolated from one of the most extreme environments in Antarctica, Union Glacier at the Ellsworth Mountains. Bacterial isolates, identified through 16 S sequencing, belong to the genera Rhodococcus, Pseudarthrobacter, and Arthrobacter. Notably, Rhodococcus sp. (EXRC-4 A-4), Pseudarthrobacter sp. (RC-2-3), and Arthrobacter sp. (EH-1B-1) tolerate UV-C radiation doses ≥ 120 J/m². Isolated UV-resistant bacteria biosynthesized CdS QDs with fluorescence intensities 4 to 8 times higher than those biosynthesized by E. coli, a mesophilic organism tolerating low doses of UV radiation. Transmission electron microscopy (TEM) analysis determined QD sizes ranging from 6 to 23 nm, and Fourier-transform infrared (FTIR) analysis demonstrated the presence of biomolecules. QDs produced by UV-resistant Antarctic bacteria exhibit high photostability after exposure to UV-B radiation, particularly in comparison to those biosynthesized by E. coli. Interestingly, red fluorescence-emitting QDs biosynthesized by Rhodococcus sp. (EXRC-4 A-4) and Arthrobacter sp. (EH-1B-1) increased their fluorescence emission after irradiation. Analysis of methylene blue degradation after exposure to irradiated QDs biosynthesized by UV-resistant bacteria, indicates that the QDs transfer their electrons to O2 for the formation of reactive oxygen species (ROS) at different levels. CONCLUSIONS: UV-resistant Antarctic bacteria represent a novel alternative for the sustainable generation of nanostructures with increased radiation tolerance-two characteristics favoring their potential application in technologies requiring continuous exposure to high-energy radiation.


Cadmium Compounds , Quantum Dots , Rhodococcus , Ultraviolet Rays , Quantum Dots/chemistry , Antarctic Regions , Cadmium Compounds/metabolism , Cadmium Compounds/chemistry , Rhodococcus/metabolism , Rhodococcus/genetics , Arthrobacter/metabolism , Arthrobacter/genetics , Sulfides/metabolism , Sulfides/chemistry
2.
Int J Mol Sci ; 25(9)2024 Apr 26.
Article En | MEDLINE | ID: mdl-38731933

Despite the promising applications of the use of quantum dots (QDs) in the biomedical field, the long-lasting effects of QDs on the cell remain poorly understood. To comprehend the mechanisms underlying the toxic effects of QDs in yeast, we characterized defects associated with receptor-mediated endocytosis (RME) as well as pinocytosis using Saccharomyces cerevisiae as a model in the presence of cadmium selenide/zinc sulfide (CdSe/ZnS) QDs. Our findings revealed that QDs led to an inefficient RME at the early, intermediate, and late stages of endocytic patch maturation at the endocytic site, with the prolonged lifespan of GFP fused yeast fimbrin (Sac6-GFP), a late marker of endocytosis. The transit of FM1-43, a lipophilic dye from the plasma membrane to the vacuole, was severely retarded in the presence of QDs. Finally, QDs caused an accumulation of monomeric red fluorescent protein fused carbamoyl phosphate synthetase 1 (mRFP-Cps1), a vacuolar lumen marker in the vacuole. In summary, the present study provides novel insights into the possible impact of CdSe/ZnS QDs on the endocytic machinery, enabling a deeper comprehension of QD toxicity.


Cadmium Compounds , Endocytosis , Quantum Dots , Saccharomyces cerevisiae , Selenium Compounds , Sulfides , Zinc Compounds , Quantum Dots/toxicity , Quantum Dots/chemistry , Endocytosis/drug effects , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/metabolism , Cadmium Compounds/toxicity , Selenium Compounds/toxicity , Sulfides/toxicity , Sulfides/metabolism , Zinc Compounds/toxicity , Vacuoles/metabolism , Vacuoles/drug effects , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae Proteins/genetics , Green Fluorescent Proteins/metabolism , Green Fluorescent Proteins/genetics , Cell Membrane/metabolism , Cell Membrane/drug effects
3.
Anal Chim Acta ; 1306: 342585, 2024 Jun 01.
Article En | MEDLINE | ID: mdl-38692786

Herein, we developed a convenient and versatile dual-mode electrochemiluminescence (ECL) and photoelectrochemistry (PEC) sensing radar for the detection of Prostate-specific antigen (PSA), which has important implications for detection of low-abundance disease-associated proteins. Cerium-based metal-organic framework (Ce-MOFs) were firstly modified on the electrode, showing well ECL and PEC property. In particular, a unique multifunctional Au@CdS quantum dots (QDs) probe loaded numerous QDs and antibody was fabricated, not only displaying strong ECL and PEC signals, but also having specific recognition to PSA. After the signal probe was linked to the electrode by immune reaction, much amplified signals of ECL and PEC were generated for double-mode detection of PSA. Therefore, this work proposed a multifunctional Au@CdS QDs signal probe with excellent ECL and PEC performance, and developed an ultrasensitive photoelectric biosensing platform for dual-mode detection, which provides an effective method for health monitoring of cancer patients.


Cadmium Compounds , Electrochemical Techniques , Metal-Organic Frameworks , Prostate-Specific Antigen , Quantum Dots , Sulfides , Quantum Dots/chemistry , Cadmium Compounds/chemistry , Sulfides/chemistry , Humans , Prostate-Specific Antigen/analysis , Prostate-Specific Antigen/blood , Metal-Organic Frameworks/chemistry , Gold/chemistry , Cerium/chemistry , Biosensing Techniques , Photochemical Processes , Limit of Detection , Electrodes , Luminescent Measurements
4.
Anal Chem ; 96(19): 7643-7650, 2024 May 14.
Article En | MEDLINE | ID: mdl-38708712

Chemiluminescence (CL), especially commercialized CL immunoassay (CLIA), is normally performed within the eye-visible region of the spectrum by exploiting the electronic-transition-related emission of the molecule luminophore. Herein, dual-stabilizers-capped CdTe nanocrystals (NCs) is employed as a model of nanoparticulated luminophore to finely tune the CL color with superior color purity. Initialized by oxidizing the CdTe NCs with potassium periodate (KIO4), intermediates of the reactive oxygen species (ROS) tend to charge CdTe NCs in both series-connection and parallel-connection routes and dominate the charge-transfer CL of CdTe NCs. The CdTe NCs/KIO4 system can exhibit color-tunable CL with the maximum emission wavelength shifted from 694 nm to 801 nm, and the red-shift span is over 100 nm. Both PL and CL of each of the CdTe NCs are bandgap-engineered; the change in the NCs surface state via CL reaction enables CL of each of the CdTe NCs to be red-shifted for ∼20 nm to PL, while the change in the NCs surface state via labeling CdTe NCs to secondary-antibody (Ab2) enables CL of the CdTe NCs-Ab2 conjugates to be red-shifted for another ∼20 nm to bare CdTe NCs. The CL of CdTe753-Ab2/KIO4 is ∼791 nm, which can perform near-infrared CL immunoassay and semi-automatically determined procalcitonin (PCT) on commercialized in vitro diagnosis (IVD) instruments.


Cadmium Compounds , Luminescent Measurements , Nanoparticles , Tellurium , Tellurium/chemistry , Immunoassay/methods , Cadmium Compounds/chemistry , Nanoparticles/chemistry , Color , Luminescence , Automation , Humans
5.
J Cardiothorac Surg ; 19(1): 188, 2024 Apr 08.
Article En | MEDLINE | ID: mdl-38589945

Pulmonary embolism is the most common cardiovascular disease after myocardial infarction and stroke. Konstantinides (Eur Heart J 41(4):543-603, 2020) Current guidelines categorize patients with PE as being at low, intermediate, and high risk of early death, with the intermediate-risk group experiencing the greatest uncertainty regarding treatment recommendations. Rapid reduction of the thrombus load by thrombolysis significantly reduces symptoms and decreases mortality, but is accompanied by a high risk of bleeding. Meyer (N Engl J Med 370(15):1402-11, 2014) Mechanical thrombectomy (CDTE) have been proven safe and efficient, yet current ESC guidelines suggest the utilization of catheter interventions only for hypotensive patients with high bleeding risk, failed systemic thrombolysis, and cardiogenic shock or if a patient does not respond to conservative therapy Konstantinides (Eur Heart J 41(4):543-603, 2020). Here, we report a case of an intermediate-risk patient with pulmonary embolism who underwent thrombus aspiration and showed significant improvement in symptoms after treatment.


Cadmium Compounds , Pulmonary Embolism , Quantum Dots , Thrombosis , Humans , Thrombectomy , Treatment Outcome , Tellurium , Pulmonary Embolism/therapy , Hemorrhage , Thrombolytic Therapy
6.
Anal Chim Acta ; 1304: 342579, 2024 May 22.
Article En | MEDLINE | ID: mdl-38637044

Plasmon enhanced fluorescent (PEF) with more "hot spots" play a critical role in signal amplified technology to avoid the intrinsic limitation of fluorophore which ascribed to a strong electromagnetic field at the tip structure. However, application of PEF technique to obtain a highly sensitive analysis of medicine was still at a very early stage. Herein, a simple but versatile Ag nanocubes (Agcubes)-based PEF sensor combined with aptamer (Agcubes@SiO2-QDs-Apt) was proposed for highly sensitive detection of berberine hydrochloride (BH). The distance between the plasma Agcubes and the red-emitted CdTe quantum dots (QDs) were regulated by the thickness of silica spacer. The three-dimensional finite-difference time-domain (3D-FDTD) simulation further revealed that Agcubes have a higher electromagnetic field than Ag nanospheres. Compared with PEF sensor, signal QDs-modified aptamer without Agcubes (QDs-Apt) showed a 10-fold higher detection limit. The linear range and detection limit of the Agcubes@SiO2-QDs-Apt were 0.1-100 µM, 87.3 nM, respectively. Furthermore, the PEF sensor was applied to analysis BH in the berberine hydrochloride tablets, compound berberine tablet and urine with good recoveries of 98.25-102.05%. These results demonstrated that the prepared PEF sensor has great potential for drug quality control and clinical analysis.


Aptamers, Nucleotide , Berberine , Cadmium Compounds , Quantum Dots , Fluorescence , Quantum Dots/chemistry , Cadmium Compounds/chemistry , Silicon Dioxide , Tellurium/chemistry , Spectrometry, Fluorescence/methods , Aptamers, Nucleotide/chemistry , Limit of Detection
7.
Chem Commun (Camb) ; 60(34): 4581-4584, 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38576349

A study of an integrated OPECT biosensor gate and the EC color-changing region on the same chip was carried out, achieving sensitive detection through bioetching-induced signal changes. Enzymatic bioetching enables specific alkaline phosphatase (ALP) detection by catalyzing the production of CdS, which modulates the channel current and generates a visual signal.


Alkaline Phosphatase , Biosensing Techniques , Electrochemical Techniques , Alkaline Phosphatase/metabolism , Alkaline Phosphatase/analysis , Transistors, Electronic , Cadmium Compounds/chemistry , Sulfides/chemistry , Photochemical Processes
8.
J Hazard Mater ; 470: 134218, 2024 May 15.
Article En | MEDLINE | ID: mdl-38581878

The development of high-performance sensors for doxycycline (DOX) detection is necessary because its residue accumulation will cause serious harm to human health and the environment. Here, a novel tri-emission ratiometric fluorescence sensor was proposed by using "post-mixing" strategy of different emissions fluorescence molecularly imprinted polymers with salicylamide as dummy template (DMIPs). BSA was chosen as assistant functional monomer, and also acted as sensitizers for the aggregation-induced emission (AIE) effect of DOX. The blue-emitting carbon dots and the red-emitting CdTe quantum dots were separately introduced into DMIPs as the response signals. Upon DOX recognition within 2 min, blue and red fluorescence of the tri-emission DMIPs sensor were quenched while green fluorescence of DOX was enhanced, resulting in a wide range of color variations observed over bluish violet-rosered-light pink-orange-yellow-green with a detection limit of 0.061 µM. The sensor possessed highly selective recognition and was successfully applied to detect DOX in complicated real samples. Moreover, with the fluorescent color collection and data processing, the smartphone-assisted visual detection of the sensors showed satisfied sensitivity with low detection limit. This work provides great potential applications for rapid and visual detection of antibiotics in complex substrates.


Anti-Bacterial Agents , Cadmium Compounds , Doxycycline , Molecular Imprinting , Quantum Dots , Spectrometry, Fluorescence , Tellurium , Doxycycline/analysis , Doxycycline/chemistry , Quantum Dots/chemistry , Tellurium/chemistry , Anti-Bacterial Agents/analysis , Cadmium Compounds/chemistry , Limit of Detection , Fluorescence , Carbon/chemistry , Fluorescent Dyes/chemistry , Molecularly Imprinted Polymers/chemistry , Smartphone
9.
Mikrochim Acta ; 191(5): 249, 2024 04 08.
Article En | MEDLINE | ID: mdl-38587558

17ß-Estradiol (E2) is the typical endocrine disruptor of steroidal estrogens and is widely used in animal husbandry and dairy processing. In the environment, even lower concentrations of E2 can cause endocrine dysfunction in organisms. Herein, we have developed a novel molecularly imprinted ratiometric fluorescent sensor based on SiO2-coated CdTe quantum dots (CdTe@SiO2) and 7-hydroxycoumarin with a post-imprint mixing strategy. The sensor selectively detected E2 in aqueous environments due to its two fluorescent signals with a self-correction function. The sensor has been successfully used for spiking a wide range of real water and milk samples. The results showed that the sensor exhibited good linearity over the concentration range 0.011-50 µg/L, obtaining satisfactory recoveries of 92.4-110.6% with precisions (RSD) < 2.5%. Moreover, this sensor obtained an ultra-low detection limit of 3.3 ng/L and a higher imprinting factor of 13.66. By using estriol (E3), as a supporting model, it was confirmed that a simple and economical ratiometric fluorescent construction strategy was provided for other hydrophobic substances.


Cadmium Compounds , Quantum Dots , Animals , Milk , Fluorescence , Silicon Dioxide , Tellurium , Estradiol , Coloring Agents
10.
Colloids Surf B Biointerfaces ; 238: 113874, 2024 Jun.
Article En | MEDLINE | ID: mdl-38581833

The growing resistance of bacteria to antibiotics has posed challenges in treating associated bacterial infections, while the development of multi-model antibacterial strategies could efficient sterilization to prevent drug resistance. High-entropy MXene has emerged as a promising candidate for antibacterial synergy with inherent photothermal and photodynamic properties. Herein, a high-entropy nanomaterial of MXene/CDs was synthesized to amplify oxidative stress under near-infrared laser irradiation. Well-exfoliated MXene nanosheets have proven to show an excellent photothermal effect for sterilization. The incorporation of CDs could provide photo-generated electrons for MXene nanosheets to generate ROS, meanwhile reducing the recombination of electron-hole pairs to further accelerate the generation of photo-generated electrons. The MXene/CDs material demonstrates outstanding synergistic photothermal and photodynamic effects, possesses excellent biocompatibility and successfully eliminates drug-resistant bacteria as well as inhibits biofilm formation. While attaining a remarkable killing efficiency of up to 99.99% against drug-resistant Escherichia coli and Staphylococcus aureus, it also demonstrates outstanding antibacterial effects against four additional bacterial strains. This work not only establishes a synthesis precedent for preparing high-entropy MXene materials with CDs but also provides a potential approach for addressing the issue of drug-resistant bacterial infections.


Anti-Bacterial Agents , Cadmium Compounds , Escherichia coli , Microbial Sensitivity Tests , Staphylococcus aureus , Sulfides , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Escherichia coli/drug effects , Staphylococcus aureus/drug effects , Sulfides/chemistry , Sulfides/pharmacology , Cadmium Compounds/chemistry , Cadmium Compounds/pharmacology , Drug Resistance, Bacterial/drug effects , Biofilms/drug effects , Particle Size , Humans , Surface Properties , Nanostructures/chemistry
11.
Int J Biol Macromol ; 268(Pt 1): 131862, 2024 May.
Article En | MEDLINE | ID: mdl-38670183

Although cadmium-based quantum dots (QDs) are highly promising candidates for numerous biological applications, their intrinsic toxicity limits their pertinency in living systems. Surface functionalization of QDs with appropriate molecules could reduce the toxicity level. Herein, we have synthesized the smaller sized (1-5 nm) aqueous-compatible biogenic CdTe QDs using human serum albumin (HSA) as a surface passivating agent via a greener approach. HSA-functionalized CdTe QDs have been explored in multiple in vitro sensing and biological applications, namely, (1) sensing, (2) anti-bacterial and (3) anti-cancer properties. Using CdTe-HSA QDs as a fluorescence probe, a simple fluorometric method has been developed for highly sensitive and selective detection of blood marker bilirubin and hazardous Hg2+ ion with a limit of detection (LOD) of 3.38 and 0.53 ng/mL, respectively. CdTe-HSA QDs also acts as a sensor for standard antibiotics, tetracycline and rifampicin with LOD values of 41.34 and 114.99 ng/mL, respectively. Nano-sized biogenic CdTe-HSA QDs have shown promising anti-bacterial activities against both gram-negative, E. coli and gram-positive, E. faecalis strains confirming more effectiveness against E. faecalis strains. The treatment of human cervical cancer cell lines (HeLa cells) with the synthesized QDs reflected the proficient cytotoxic properties of QDs.


Anti-Bacterial Agents , Biosensing Techniques , Cadmium Compounds , Quantum Dots , Serum Albumin, Human , Tellurium , Quantum Dots/chemistry , Tellurium/chemistry , Humans , Cadmium Compounds/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Biosensing Techniques/methods , Serum Albumin, Human/chemistry , Escherichia coli/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Cell Survival/drug effects , Bilirubin
12.
Talanta ; 274: 126024, 2024 Jul 01.
Article En | MEDLINE | ID: mdl-38583330

The detection of transmissible gastroenteritis virus (TGEV) is of great significance to reduce the loss of pig industry. A LAMP-visualization/PFC self-powered dual-mode output sensor platform was constructed to detect TGEV by combining a simple and intuitive photoelectrochromic material with a highly sensitive PFC self-powered sensing platform without external power supply. The PFC sensing substrate was constructed using CdS nanoparticles modified ZnO NRs (CdS/ZnO NRs) as the photoanode, which exhibited high photoactivity, and Prussian blue (PB) as the cathode. After LAMP reaction on the optical anode, visual signals caused by PB discolorimetry can be detected semi-quantitatively, or PFC power density electrical signals collected by electrochemical workstation can be used. The output power density value is logarithm of TGEV concentration. The linear relationship was good within the detection range of 0.075 fg/µL-7.5 ng/µL, with a detection limit of 0.025 fg/µL (S/N = 3). This multi-signal output sensing platform provides more choices for quantifying TGEV detection results, and the two methods can be mutually verified, which meets the needs of different scenarios and improves the reliability of detection. It has a good effect in the actual sample detection, without the use of expensive and complex instruments, and has a broad application prospect.


Fluorocarbon Polymers , Molecular Diagnostic Techniques , Nucleic Acid Amplification Techniques , Transmissible gastroenteritis virus , Zinc Oxide , Transmissible gastroenteritis virus/isolation & purification , Zinc Oxide/chemistry , Animals , Swine , Limit of Detection , Cadmium Compounds/chemistry , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Nanoparticles/chemistry , Sulfides/chemistry
13.
Int J Mol Sci ; 25(8)2024 Apr 10.
Article En | MEDLINE | ID: mdl-38673765

Quantum dots (QDs) are a novel type of nanomaterial that has unique optical and physical characteristics. As such, QDs are highly desired because of their potential to be used in both biomedical and industrial applications. However, the mass adoption of QDs usage has raised concerns among the scientific community regarding QDs' toxicity. Although many papers have reported the negative impact of QDs on a cellular level, the exact mechanism of the QDs' toxicity is still unclear. In this investigation, we study the adverse effects of QDs by focusing on one of the most important cellular processes: actin polymerization and depolymerization. Our results showed that QDs act in a biphasic manner where lower concentrations of QDs stimulate the polymerization of actin, while high concentrations of QDs inhibit actin polymerization. Furthermore, we found that QDs can bind to filamentous actin (F-actin) and cause bundling of the filament while also promoting actin depolymerization. Through this study, we found a novel mechanism in which QDs negatively influence cellular processes and exert toxicity.


Actins , Cadmium Compounds , Quantum Dots , Selenium Compounds , Sulfides , Zinc Compounds , Quantum Dots/chemistry , Actins/metabolism , Zinc Compounds/chemistry , Sulfides/chemistry , Cadmium Compounds/chemistry , Selenium Compounds/chemistry , Polymerization , Animals , Actin Cytoskeleton/metabolism , Actin Cytoskeleton/drug effects , Humans
14.
Chemosphere ; 356: 141948, 2024 May.
Article En | MEDLINE | ID: mdl-38604521

Surface reaction is a prominent aspect that affects the efficiency of photocatalysis. In this work, acid theory was employed to facilitate the reaction dynamics and enhance the interfacial effect between photocatalysts and target molecules. The photocatalytic removal efficiency of NTP was 66 % for bare CdS in 50 min with apparent rate constants of 0.023 compare to 96 % with apparent rate constants of 0.065 for 5% Ce-CdS. The introduced Ce atom as bifunctional active site reduces the energy barrier of O2 adsorption, strengthens the interfacial effect and accelerates the electrons transfer, which could facilitate surface reaction process and boost the photocatalytic performance.


Photochemical Processes , Catalysis , Adsorption , Cadmium Compounds/chemistry , Water Pollutants, Chemical/chemistry , Sulfides/chemistry , Cerium/chemistry
15.
Anal Chem ; 96(18): 7073-7081, 2024 May 07.
Article En | MEDLINE | ID: mdl-38663374

A spatial-potential-color-resolved bipolar electrode electrochemiluminescence biosensor (BPE-ECL) using a CuMoOx electrocatalyst was constructed for the simultaneous detection and imaging of tetracycline (TET) and lincomycin (LIN). HOF-101 emitted peacock blue light under positive potential scanning, and CdSe quantum dots (QDs) emitted green light under negative potential scanning. CuMoOx could catalyze the electrochemical reduction of H2O2 to greatly increase the Faradic current of BPE and realize the ECL signal amplification. In channel 1, CuMoOx-Aptamer II (TET) probes were introduced into the BPE hole (left groove A) by the dual aptamer sandwich method of TET. During positive potential scanning, the polarity of BPE (left groove A) was negative, resulting in the electrochemical reduction of H2O2 catalyzed by CuMoOx, and the ECL signal of HOF-101 was enhanced for detecting TET. In channel 2, CuMoOx-Aptamer (LIN) probes were adsorbed on the MXene of the driving electrode (DVE) hole (left groove B) by hydrogen-bonding and metal-chelating interactions. LIN bound with its aptamers, causing CuMoOx to fall off. During negative potential scanning, the polarity of DVE (left groove B) was negative and the Faradic current decreased. The ECL signal of CdSe QDs was reduced for detecting LIN. Furthermore, a portable mobile phone imaging platform was built for the colorimetric (CL) detection of TET and LIN. Thus, the multiple mode-resolved detection of TET and LIN could be realized simultaneously with only one potential scan, which greatly improved detection accuracy and efficiency. This study opened a new technology of BPE-ECL sensor application and is expected to shine in microchips and point-of-care testing (POCT).


Biosensing Techniques , Electrochemical Techniques , Electrodes , Lincomycin , Luminescent Measurements , Tetracycline , Tetracycline/analysis , Tetracycline/chemistry , Biosensing Techniques/methods , Lincomycin/analysis , Electrochemical Techniques/methods , Luminescent Measurements/methods , Catalysis , Quantum Dots/chemistry , Cadmium Compounds/chemistry , Aptamers, Nucleotide/chemistry , Selenium Compounds/chemistry , Hydrogen Peroxide/chemistry , Hydrogen Peroxide/analysis , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/chemistry
16.
Biosens Bioelectron ; 257: 116324, 2024 Aug 01.
Article En | MEDLINE | ID: mdl-38669844

Exploring efficient photoactive material presents an intriguing opportunity to enhance the analytical performance of photoelectrochemical (PEC) sensor in the environmental analysis. In this work, a sandwich-structured multi-interface Co9S8@ZnIn2S4/CdSe QDs dual Z-Scheme heterojunction, derived from metal-organic framework (MOF), was synthesized as a sensing platform for chlorpyrifos detection, by integrating with enzyme-induced in situ insoluble precipitates strategy. The meticulously designed Co9S8@ZnIn2S4/CdSe QDs exhibited enhanced charge separation efficiency and was proved to be a highly effective sensing platform for the immobilization of biomolecules, attributing to the intrinsic dual Z-Scheme heterojunction and the distinctive hollow structure. The proposed PEC sensing platform combined with enzyme-induced in situ precipitate signal amplification strategy achieved superior performance for sensing of chlorpyrifos (CPF), showing in wide linear range (1.0 pg mL-1-100 ng mL-1), with a limit of detection (0.6 pg mL-1), excellent selectivity, and stability. This work offers valuable insights for the design of novel advanced photoactive materials aimed at detecting environmental pollutants with low level concentration.


Biosensing Techniques , Chlorpyrifos , Electrochemical Techniques , Limit of Detection , Metal-Organic Frameworks , Quantum Dots , Chlorpyrifos/analysis , Metal-Organic Frameworks/chemistry , Electrochemical Techniques/methods , Quantum Dots/chemistry , Cadmium Compounds/chemistry , Selenium Compounds/chemistry , Cobalt/chemistry , Insecticides/analysis
17.
Chemosphere ; 357: 141966, 2024 Jun.
Article En | MEDLINE | ID: mdl-38614401

Chromium is widely recognized as a significant pollutant discharged into the environment by various industrial activities. The toxicity of this element is dependent on its oxidation state, making speciation analysis crucial for monitoring the quality of environmental water and assessing the potential risks associated with industrial waste. This study introduces a single-well fluorometric sensor that utilizes orange emissive thioglycolic acid stabilized CdTe quantum dots (TGA-QDs) and blue emissive carbon dots (CDs) to detect and differentiate between various chromium species, such as Cr (III) and Cr (VI) (i.e., CrO42- and Cr2O72-). The variations of fluorescence spectra of the proposed probe upon chromium species addition were analyzed using machine learning techniques such as linear discriminant analysis and partial least squares regression as a classification and multivariate calibration technique, respectively. Linear discriminant analysis (LDA) demonstrated exceptional accuracy in differentiating single-component and bicomponent samples. Additionally, the findings from the partial least squares regression (PLSR) showed that the sensor created has strong linearity within the 1.0-100.0, 1.0-100.0, and 0.1-15 µM range for Cr2O72-, CrO42-, and Cr3+, respectively. Furthermore, appropriate detection limits were successfully achieved, which were 2.6, 2.9, and 0.7 µM for Cr2O72-, CrO42-, and Cr3+, respectively. Ultimately, the successful capability of the sensing platform in the identification and quantification of chromium species in environmental water samples provides innovative insights into general speciation analytics.


Chromium , Machine Learning , Quantum Dots , Water Pollutants, Chemical , Chromium/analysis , Chromium/chemistry , Quantum Dots/chemistry , Water Pollutants, Chemical/analysis , Least-Squares Analysis , Fluorescent Dyes/chemistry , Discriminant Analysis , Tellurium/chemistry , Environmental Monitoring/methods , Cadmium Compounds/chemistry , Spectrometry, Fluorescence/methods , Carbon/chemistry
18.
Anal Chem ; 96(18): 7274-7280, 2024 May 07.
Article En | MEDLINE | ID: mdl-38655584

Inspired by natural DNA networks, programmable artificial DNA networks have become an attractive tool for developing high-performance biosensors. However, there is still a lot of room for expansion in terms of sensitivity, atom economy, and result self-validation for current microRNA sensors. In this protocol, miRNA-122 as a target model, an ultrasensitive fluorescence (FL) and photoelectrochemical (PEC) dual-mode biosensing platform is developed using a programmable entropy-driven circuit (EDC) cascaded self-feedback DNAzyme network. The well-designed EDC realizes full utilization of the DNA strands and improves the atomic economy of the signal amplification system. The unique and rational design of the double-CdSe quantum-dot-released EDC substrate and the cascaded self-feedback DNAzyme amplification network significantly avoids high background signals and enhances sensitivity and specificity. Also, the enzyme-free, programmable EDC cascaded DNAzyme network effectively avoids the risk of signal leakage and enhances the accuracy of the sensor. Moreover, the introduction of superparamagnetic Fe3O4@SiO2-cDNA accelerates the rapid extraction of E2-CdSe QDs and E3-CdSe QDs, which greatly improves the timeliness of sensor signal reading. In addition to the strengths of linear range (6 orders of magnitude) and stability, the biosensor design with dual signal reading makes the test results self-confirming.


Biosensing Techniques , DNA, Catalytic , Electrochemical Techniques , DNA, Catalytic/chemistry , DNA, Catalytic/metabolism , Entropy , Quantum Dots/chemistry , MicroRNAs/analysis , Spectrometry, Fluorescence , Photochemical Processes , Fluorescence , Humans , Cadmium Compounds/chemistry , Selenium Compounds/chemistry , Limit of Detection
19.
Anal Chem ; 96(17): 6847-6852, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38639290

Organic photoelectrochemical transistor (OPECT) has shown substantial potential in the development of next-generation bioanalysis yet is limited by the either-or situation between the photoelectrode types and the channel types. Inspired by the dual-photoelectrode systems, we propose a new architecture of dual-engine OPECT for enhanced signal modulation and its biosensing application. Exemplified by incorporating the CdS/Bi2S3 photoanode and Cu2O photocathode within the gate-source circuit of Ag/AgCl-gated poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) channel, the device shows enhanced modulation capability and larger transconductance (gm) against the single-photoelectrode ones. Moreover, the light irritation upon the device effectively shifts the peak value of gm to zero gate voltage without degradation and generates larger current steps that are advantageous for the sensitive bioanalysis. Based on the as-developed dual-photoelectrode OPECT, target-mediated recycling and etching reactions are designed upon the CdS/Bi2S3, which could result in dual signal amplification and realize the sensitive microRNA-155 biodetection with a linear range from 1 fM to 100 pM and a lower detection limit of 0.12 fM.


Copper , Electrochemical Techniques , Sulfides , Thiophenes , Electrochemical Techniques/instrumentation , Copper/chemistry , Sulfides/chemistry , Cadmium Compounds/chemistry , Biosensing Techniques/instrumentation , Bismuth/chemistry , Transistors, Electronic , Photochemical Processes , Polystyrenes/chemistry , MicroRNAs/analysis , Electrodes , Polymers/chemistry
20.
Phys Med Biol ; 69(7)2024 Apr 03.
Article En | MEDLINE | ID: mdl-38471186

Following the rapid, but independent, diffusion of x-ray spectral and phase-contrast systems, this work demonstrates the first combination of spectral and phase-contrast computed tomography (CT) obtained by using the edge-illumination technique and a CdTe small-pixel (62µm) spectral detector. A theoretical model is introduced, starting from a standard attenuation-based spectral decomposition and leading to spectral phase-contrast material decomposition. Each step of the model is followed by quantification of accuracy and sensitivity on experimental data of a test phantom containing different solutions with known concentrations. An example of a micro CT application (20µm voxel size) on an iodine-perfusedex vivomurine model is reported. The work demonstrates that spectral-phase contrast combines the advantages of spectral imaging, i.e. high-Zmaterial discrimination capability, and phase-contrast imaging, i.e. soft tissue sensitivity, yielding simultaneously mass density maps of water, calcium, and iodine with an accuracy of 1.1%, 3.5%, and 1.9% (root mean square errors), respectively. Results also show a 9-fold increase in the signal-to-noise ratio of the water channel when compared to standard spectral decomposition. The application to the murine model revealed the potential of the technique in the simultaneous 3D visualization of soft tissue, bone, and vasculature. While being implemented by using a broad spectrum (pink beam) at a synchrotron radiation facility (Elettra, Trieste, Italy), the proposed experimental setup can be readily translated to compact laboratory systems including conventional x-ray tubes.


Cadmium Compounds , Iodine , Quantum Dots , Mice , Animals , Lighting , Photons , Tellurium , Tomography, X-Ray Computed/methods , Phantoms, Imaging
...