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1.
Angew Chem Int Ed Engl ; : e202409145, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38869085

RESUMEN

Metal hexacyanoferrates (HCFs) are regarded as promising cathode materials for potassium-ion batteries (PIBs) on account of their low cost and high energy density. However, the difficult-to-remove [Fe(CN)6] vacancies and crystal water lead to structural instability and capacity deterioration as well as the stereotype of poor thermostability of conventional HCFs. Herein, we report (100) face-oriented potassium magnesium hexacyanoferrate (KMgHCF) nanoplates with low [Fe(CN)6] vacancies and high crystallinity, enabling thermostability up to 550 °C, high-temperature carbon coating and crystal water elimination. The as-obtained KMgHCF/C nanoplates exhibit superior potassium storage properties, including a large reversible capacity of 84.6 mAh g-1, a high voltage plateau of 3.87 V, excellent long-term cycling performance over 15000 cycles and high rate capability at 5 A g-1. The unprecedented cycling stability of KMgHCF/C is attributed to the synergistic effect of a highly reversible two-phase reaction, low [Fe(CN)6] vacancies and no crystal water, a specially exposed steady (100) surface, and a protective carbon coating. This work provides a new material selection and modification strategy for the practical application of HCFs in PIBs.

2.
Chem Soc Rev ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38855863

RESUMEN

The growing global energy demand necessitates the development of renewable energy solutions to mitigate greenhouse gas emissions and air pollution. To efficiently utilize renewable yet intermittent energy sources such as solar and wind power, there is a critical need for large-scale energy storage systems (EES) with high electrochemical performance. While lithium-ion batteries (LIBs) have been successfully used for EES, the surging demand and price, coupled with limited supply of crucial metals like lithium and cobalt, raised concerns about future sustainability. In this context, potassium-ion batteries (PIBs) have emerged as promising alternatives to commercial LIBs. Leveraging the low cost of potassium resources, abundant natural reserves, and the similar chemical properties of lithium and potassium, PIBs exhibit excellent potassium ion transport kinetics in electrolytes. This review starts from the fundamental principles and structural regulation of PIBs, offering a comprehensive overview of their current research status. It covers cathode materials, anode materials, electrolytes, binders, and separators, combining insights from full battery performance, degradation mechanisms, in situ/ex situ characterization, and theoretical calculations. We anticipate that this review will inspire greater interest in the development of high-efficiency PIBs and pave the way for their future commercial applications.

3.
Front Pediatr ; 11: 1161421, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124181

RESUMEN

Purpose: This systematic review aimed to analyze the characteristics of different diagnostic techniques for micrognathia, summarize the consistent diagnostic criteria of each technique, and provide a simple and convenient prenatal diagnosis strategy for micrognathia. Methods: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the search was undertaken in three international databases (PubMed, Scopus, and Web of Science). The three reviewers assessed all papers and extracted the following variables: author's name and year of publication, country, study design, number of participants, gestational age, equipment for prenatal examination, biometric parameters related to micrognathia, main results. Results: A total of 25 articles included in the analysis. Nineteen articles described cross-sectional studies (76 percent), 4 (16 percent) were case-control studies, and 2 (8 percent) were cohort studies. Fifteen studies (60 percent) had a prospective design, 9 (36 percent) had a retrospective design, and one (4 percent) had both prospective and retrospective design. Thirty-two percent of the studies (n = 8) were performed in USA, and the remaining studies were performed in China (n = 4), Israel (n = 3), Netherlands (n = 3), UK (n = 1), France (n = 1), Italy (n = 1), Belgium(n = 1), Germany (n = 1), Spain (n = 1), and Austria (n = 1). The prenatal diagnosis of micrognathia can be performed as early as possible in the first trimester, while the second and third trimester of pregnancy were the main prenatal diagnosis period. The articles that were included in the qualitative synthesis describe 30 biometric parameters related to the mandible. Conclusion: Of the 30 biometric parameters related to the mandible, 15 can obtain the simple and convenient diagnostic criteria or warning value for micrognathia. Based on these diagnostic criteria or warning value, clinicians can quickly make a preliminary judgment on facial deformities, to carry out cytologic examination to further clarify the diagnosis of micrognathia.

4.
Front Immunol ; 14: 1139775, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37168863

RESUMEN

Keloid is a pathological scar formed by abnormal wound healing, characterized by the persistence of local inflammation and excessive collagen deposition, where the intensity of inflammation is positively correlated with the size of the scar formation. The pathophysiological mechanisms underlying keloid formation are unclear, and keloid remains a therapeutic challenge in clinical practice. This study is the first to investigate the role of glycosphingolipid (GSL) metabolism pathway in the development of keloid. Single cell sequencing and microarray data were applied to systematically analyze and screen the glycosphingolipid metabolism related genes using differential gene analysis and machine learning algorithms (random forest and support vector machine), and a set of genes, including ARSA,GBA2,SUMF2,GLTP,GALC and HEXB, were finally identified, for which keloid diagnostic model was constructed and immune infiltration profiles were analyzed, demonstrating that this set of genes could serve as a new therapeutic target for keloid. Further unsupervised clustering was performed by using expression profiles of glycosphingolipid metabolism genes to discover keloid subgroups, immune cells, inflammatory factor differences and the main pathways of enrichment between different subgroups were calculated. The single-cell resolution transcriptome landscape concentrated on fibroblasts. By calculating the activity of the GSL metabolism pathway for each fibroblast, we investigated the activity changes of GSL metabolism pathway in fibroblasts using pseudotime trajectory analysis and found that the increased activity of the GSL metabolism pathway was associated with fibroblast differentiation. Subsequent analysis of the cellular communication network revealed the existence of a fibroblast-centered communication regulatory network in keloids and that the activity of the GSL metabolism pathway in fibroblasts has an impact on cellular communication. This contributes to the further understanding of the pathogenesis of keloids. Overall, we provide new insights into the pathophysiological mechanisms of keloids, and our results may provide new ideas for the diagnosis and treatment of keloids.


Asunto(s)
Queloide , Humanos , Queloide/patología , Colágeno/metabolismo , Metabolismo de los Lípidos , Inflamación/complicaciones , Diferenciación Celular , Sulfatasas/metabolismo
5.
Small ; 19(34): e2301954, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37086143

RESUMEN

Magnesium-ion batteries (MIBs) are emerging as potential next-generation energy storage systems due to high security and high theoretical energy density. Nevertheless, the development of MIBs is limited by the lack of cathode materials with high specific capacity and cyclic stability. Currently, transition metal sulfides are considered as a promising class of cathode materials for advanced MIBs. Herein, a template-based strategy is proposed to successfully fabricate metal-organic framework-derived in-situ porous carbon nanorod-encapsulated CuS quantum dots (CuS-QD@C nanorods) via a two-step method of sulfurization and cation exchange. CuS quantum dots have abundant electrochemically active sites, which facilitate the contact between the electrode and the electrolyte. In addition, the tight combination of CuS quantum dots and porous carbon nanorods increases the electronic conductivity while accelerating the transport speed of ions and electrons. With these architectural and compositional advantages, when used as a cathode material for MIBs, the CuS-QD@C nanorods exhibit remarkable performance in magnesium storage, including a high reversible capacity of 323.7 mAh g-1 at 100 mA g-1 after 100 cycles, excellent long-term cycling stability (98.5 mAh g-1 after 1000 cycles at 1.0 A g-1 ), and satisfying rate performance (111.8 mA g-1 at 1.0 A g-1 ).

6.
Nano Lett ; 23(2): 694-700, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36629141

RESUMEN

Layered transition-metal (TM) oxides have drawn ever-growing interest as positive electrode materials in potassium-ion batteries (PIBs). Nevertheless, the practical implementation of these positive electrode materials is seriously hampered by their inferior cyclic property and rate performance. Reported here is a self-templating strategy to prepare homogeneous P2-K0.6CoO2 (KCO) microcubes. Benefiting from the unusual microcube architecture, the interface between the electrolyte and the active material is considerably diminished. As a result, the KCO microcubes manifest boosted electrochemical properties for potassium storage including large reversible capacity (87.2 mAh g-1 under 20 mA g-1), superior rate performance, and ultralong cyclic steady (an improved capacity retention of 86.9% under 40 mA g-1 after 1000 cycles). More importantly, the fabrication approach can be effectively extended to prepare other layered TM oxide (P3-K0.5MnO2, P3-K0.5Mn0.8Fe0.2O2, P2-K0.6Co0.67Mn0.33O2, and P2-K0.6Co0.66Mn0.17Ni0.17O2) microcubes and nonlayered TM oxide (KFeO2) microcubes.

7.
Sci Bull (Beijing) ; 67(21): 2208-2215, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36545996

RESUMEN

Orthorhombic iron-based fluorosulfate KFeSO4F represents one of the most promising cathode materials due to its high theoretical capacity, high voltage plateau, unique three-dimensional conduction pathway for potassium ions, and low cost. Yet, the poor thermostability and intrinsic low electronic conductivity of KFeSO4F challenge its synthesis and electrochemical performance in potassium-ion batteries (PIBs). Herein, we report, for the first time, judicious crafting of carbon nanotubes (CNTs)-interwoven KFeSO4F microspheres in diethylene glycol (DEG) (denoted KFSF@CNTs/DEG) as the cathode to render high-performance PIBs, manifesting an outstanding reversible capacity of 110.9 mAh g-1 at 0.2 C, a high working voltage of 3.73 V, and a long-term capacity retention of 93.9% after 2000 cycles at 3 C. Specifically, KFSF@CNTs/DEG microspheres are created via introducing CNTs into the precursors DEG solution at relatively low temperature. Notably, the strong binding of the ether groups in DEG retards the nucleation and growth of KFSF, leading to in situ formation of microspheres with CNTs interwoven within KFSF crystals, thereby greatly enhancing electronic conductivity of KFSF. Intriguingly, the remarkable electrochemical performance of KFSF@CNTs/DEG cathode is found to stem from the massively exposed (100) plane and uniform interpenetration of CNTs inside KFSF microsphere. More importantly, in situ X-ray diffraction and electrochemical kinetics study unveil outstanding structural stability and high K+ diffusion rate of KFSF@CNTs/DEG. Finally, the KFSF@CNTs/DEG//graphite full cell displays a large energy density of ∼243 Wh kg-1. Such simple route to KFSF@CNTs/DEG highlights the robustness of creating inexpensive CNTs-interwoven polyanionic cathodes for high-performance PIBs.

8.
Nano Lett ; 22(12): 4933-4940, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35671041

RESUMEN

With high theoretical capacity and operating voltage, KVPO4F is a potential high energy density cathode material for potassium-ion batteries. However, its performance is usually limited by F loss, poor electronic conductivity, and unsteady electrode/electrolyte interface. Herein, a simple one-step sintering process is developed, where vanadium-oxalate-phosphite/phosphate frameworks and fluorinated polymer are used to synthesize carbon-coated KVPO4F nanoplates. It is found that the V-F-C bond generated by fluorinated-polymer-derived carbon at the interface of KVPO4F/C nanoplates diminishes the F loss, as well as enhances K-ions migration ability and the electronic conductivity of KVPO4F. The as-synthesized KVPO4F/C cathode delivers a reversible capacity of 106.5 mAh g-1 at 0.2 C, a high working voltage of 4.28 V, and a rate capability with capacity of 73.8 mAh g-1 at the ultrahigh current density of 100 C. In addition, a KVPO4F/C//soft carbon full cell exhibits a high energy density of 235.5 Wh kg-1.

9.
Anal Chem ; 94(22): 8050-8057, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35615910

RESUMEN

The trans-cleavage activity of CRISPR/Cas12a has been widely used in biosensing applications. However, the lack of exploration on the fundamental properties of CRISPR/Cas12a not only discourages further in-depth studies of the CRISPR/Cas12a system but also limits the design space of CRISPR/Cas12a-based applications. Herein, a "RESET" effect (random extending sequences enhance trans-cleavage activity) is discovered for the activation of CRISPR/Cas12a trans-cleavage activity. That is, a single-stranded DNA, which is too short to work as the activator, can efficiently activate CRISPR/Cas12a after being extended a random sequence from its 3'-end, even when the random sequence folds into secondary structures. The finding of the "RESET" effect enriches the CRISPR/Cas12a-based sensing strategies. Based on this effect, two CRISPR/Cas12a-based biosensors are designed for the sensitive and specific detection of two biologically important enzymes.


Asunto(s)
Técnicas Biosensibles , Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , ADN de Cadena Simple/genética
10.
Ying Yong Sheng Tai Xue Bao ; 33(2): 297-303, 2022 Feb.
Artículo en Chino | MEDLINE | ID: mdl-35229501

RESUMEN

The aims of this study were to clarify the regeneration characteristics and dominant factors affecting the regeneration of three natural Juniperus forests in the Three-River Headwater Region of Qinghai Province, and thus to provide a reference for the protection and management of natural forests. We evaluated the natural regeneration levels of Juniperus forests, and the effects of stand factors and soil factors on natural regeneration. The results showed that three natural Juniperus forests were poorly regenerated, with insufficient regeneration potential. The average regeneration density of J. tibetica forest, J. przewalskii forest and J. convallium forest was 332, 279 and 202 ind·hm-2, respectively. The height range of regenerate individuals was concentrated in 1-3 m. Only a few seedlings (12 ind·hm-2) were found under the J. tibetica forest, and no seedlings were found under the J. convallium and J. przewalskii forests. The regeneration density of J. tibetica forest was significantly positively correlated with stand density, soil organic matter and available phosphorus, and negatively correlated with shrub coverage. The regeneration density of J. convallium forest was significantly negatively correlated with herb coverage, human disturbance degree, woodland slope and soil total nitrogen, and positively correlated with soil water content. The regeneration density of J. przewalskii forest was significantly positively correlated with stand density, soil available potassium and available phosphorus, but negatively correlated with herb coverage. Results of multiple regression analysis showed that the regeneration of J. tibetica forest was mainly affected by understory shrub coverage and soil available phosphorus, that of J. convallium forest was mainly affected by understory herb coverage, soil total nitrogen and human disturbance, and that of J. przewalskii forest was mainly affected by understory herb coverage and soil available potassium. It was necessary to strengthen forest enclosure, management and protection, rationally regu-late the coverage of understory vegetation, increase soil fertility and improve biotope in the forest, which would promote the protection and natural regeneration of natural Juniperus forests in the Three-River Headwater Region.


Asunto(s)
Juniperus , China , Bosques , Humanos , Ríos , Suelo
11.
Biosens Bioelectron ; 197: 113739, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34781175

RESUMEN

The molecular biomarkers are molecules that are closely related to specific physiological states. Numerous molecular biomarkers have been identified as targets for disease diagnosis and biological research. To date, developing highly efficient probes for the precise detection of biomarkers has become an attractive research field which is very important for biological and biochemical studies. During the past decades, not only the small chemical probe molecules but also the biomacromolecules such as enzymes, antibodies, and nucleic acids have been introduced to construct of biosensor platform to achieve the detection of biomarkers in a highly specific and highly efficient way. Nevertheless, improving the performance of the biosensors, especially in clinical applications, is still in urgent demand in this field. A noteworthy example is the Corona Virus Disease 2019 (COVID-19) that breaks out globally in a short time in 2020. The COVID-19 was caused by the virus called SARS-CoV-2. Early diagnosis is very important to block the infection of the virus. Therefore, during these months scientists have developed dozens of methods to achieve rapid and sensitive detection of the virus. Nowadays some of these new methods have been applied for producing the commercial detection kit and help people against the disease worldwide. DNA-based biosensors are useful tools that have been widely applied in the detection of molecular biomarkers. The good stability, high specificity, and excellent biocompatibility make the DNA-based biosensors versatile in application both in vitro and in vivo. In this paper, we will review the major methods that emerged in recent years on the design of DNA-based biosensors and their applications. Moreover, we will also briefly discuss the possible future direction of DNA-based biosensors design. We believe this is helpful for people interested in not only the biosensor field but also in the field of analytical chemistry, DNA nanotechnology, biology, and disease diagnosis.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Biomarcadores , ADN/genética , Humanos , SARS-CoV-2
12.
Chem Commun (Camb) ; 57(87): 11497-11500, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34651621

RESUMEN

We demonstrate an economical polytetrafluoroethylene-assisted fluorination method to synthesize three binary sodium-rich fluorides Na2MVF7 (M = Mn, Fe, and Co). The optimal Na2FeVF7 cathode delivers a high reversible capacity of 146.5 mA h g-1 based on active Fe2+/Fe3+ and V3+/V4+ redox reactions in sodium-ion batteries. A steady cycling performance with a high capacity retention of 95% over 200 cycles is achieved owing to the negligible structural change during Na+ insertion/extraction.

13.
Anal Chim Acta ; 1185: 338882, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34711321

RESUMEN

CRISPR (clustered regularly interspaced short palindromic repeats)/Cas (CRISPR-associated) proteins are powerful gene-editing tools because of their ability to accurately recognize and manipulate nucleic acids. Besides gene-editing function, they also show great promise in biosensing applications due to the superiority of easy design and precise targeting. To improve the performance of CRISPR/Cas-based biosensing systems, various nucleic acid-based signal amplification techniques are elaborately incorporated. The incorporation of these amplification techniques not only greatly increases the detection sensitivity and specificity, but also extends the detectable target range, as well as makes the use of various signal output modes possible. Therefore, summarizing the use of signal amplification techniques in sensing systems and elucidating their roles in improving sensing performance are very necessary for the development of more superior CRISPR/Cas-based biosensors for various applications. In this review, CRISPR/Cas-based biosensors are summarized from two aspects: the incorporation of signal amplification techniques in three kinds of CRISPR/Cas-based biosensing systems (Cas9, Cas12 and Cas13-based ones) and the signal output modes used by these biosensors. The challenges and prospects for the future development of CRISPR/Cas-based biosensors are also discussed.


Asunto(s)
Técnicas Biosensibles , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , Edición Génica , Sensibilidad y Especificidad
14.
Angew Chem Int Ed Engl ; 60(48): 25575-25582, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34559443

RESUMEN

Most potassium-ion battery (PIB) cathode materials have deficient structural stability because of the huge radius of potassium ion, leading to inferior cycling performance. We report the controllable synthesis of a novel low-strain phosphate material K3 (VO)(HV2 O3 )(PO4 )2 (HPO4 ) (denoted KVP) nanorulers as an efficient cathode for PIBs. The as-synthesized KVP nanoruler cathode exhibits an initial reversible capacity of 80.6 mAh g-1 under 20 mA g-1 , with a large average working potential of 4.11 V. It also manifests an excellent rate property of 54.4 mAh g-1 under 5 A g-1 , with a high capacity preservation of 92.1 % over 2500 cycles. The outstanding potassium storage capability of KVP nanoruler cathode originates from a low-strain K+ uptake/removal mechanism, inherent semiconductor characteristic, and small K+ migration energy barrier. The high energy density and prolonged cyclic stability of KVP nanorulers//polyaniline-intercalated layered titanate full battery verifies the superiority of KVP nanoruler cathode in PIBs.

15.
Chem Sci ; 12(22): 7602-7622, 2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34168817

RESUMEN

In recent years, DNA has been widely noted as a kind of material that can be used to construct building blocks for biosensing, in vivo imaging, drug development, and disease therapy because of its advantages of good biocompatibility and programmable properties. However, traditional DNA-based sensing processes are mostly achieved by random diffusion of free DNA probes, which were restricted by limited dynamics and relatively low efficiency. Moreover, in the application of biosystems, single-stranded DNA probes face challenges such as being difficult to internalize into cells and being easily decomposed in the cellular microenvironment. To overcome the above limitations, DNA nanostructure-based probes have attracted intense attention. This kind of probe showed a series of advantages compared to the conventional ones, including increased biostability, enhanced cell internalization efficiency, accelerated reaction rate, and amplified signal output, and thus improved in vitro and in vivo applications. Therefore, reviewing and summarizing the important roles of DNA nanostructures in improving biosensor design is very necessary for the development of DNA nanotechnology and its applications in biology and pharmacology. In this perspective, DNA nanostructure-based probes are reviewed and summarized from several aspects: probe classification according to the dimensions of DNA nanostructures (one, two, and three-dimensional nanostructures), the common connection modes between nucleic acid probes and DNA nanostructures, and the most important advantages of DNA self-assembled nanostructures in the applications of biosensing, imaging analysis, cell assembly, cell capture, and theranostics. Finally, the challenges and prospects for the future development of DNA nanostructure-based nucleic acid probes are also discussed.

16.
Analyst ; 146(8): 2600-2608, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33721010

RESUMEN

Accurate and specific analysis of adenosine triphosphate (ATP) expression levels in living cells can provide valuable information for understanding cell metabolism, physiological activities and pathologic mechanisms. Herein, DNA nanolantern-based split aptamer nanoprobes are prepared and demonstrated to work well for in situ analysis of ATP expression in living cells. The nanoprobes, which carry multiple split aptamer units on the surface, are easily and inexpensively prepared by a "one-pot" assembly reaction of four short oligonucleotide strands. A series of characterization experiments verify that the nanoprobes have good monodispersity, strong biostability, high cell internalization efficiency, and fluorescence resonance energy transfer (FRET)-based ratiometric response to ATP in the concentration range covering the entire intracellular ATP expression level. By changing the intracellular ATP level via different treatments, the nanoprobes are demonstrated to show excellent performance in intracellular ATP expression analysis, giving a highly ATP concentration-dependent ratiometric fluorescence signal output. ATP-induced formation of large-sized DNA aggregates not only amplifies the FRET signal output, but also makes in situ ATP-imaging analysis in living cells possible. In situ responsive crosslinking of nanoprobes also makes them capable of lighting up the mitochondria of living cells. By simply changing the split aptamer sequence, the proposed DNA nanolantern-based split aptamer strategy might be easily extended to other targets.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Adenosina Trifosfato , ADN , Sondas de ADN , Mitocondrias
17.
Biosens Bioelectron ; 171: 112734, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33069955

RESUMEN

A simple and highly sensitive biosensing strategy was reported by cascading terminal deoxynucleotidyl transferase (TdT)-catalyzed substrate extension and CRISPR-Cas12a -catalyzed short-stranded DNA probe cleavage. Such a strategy, which is named as TdT-combined CRISPR-Cas12a amplification, gives excellent signal amplification capability due to the synergy of two amplification steps, and thus shows great promise in the design of various biosensors. Based on this strategy, two representative biosensors were developed by simply adjusting the DNA substrate design. High signal amplification efficiency and nearly zero background endowed the biosensors with extraordinary high sensitivity. By utilizing these two biosensors, ultrasensitive detection of uracil-DNA glycosylase (UDG) and T4 polynucleotide kinase (T4 PNK) was achieved with the detection limit as low as 5 × 10-6 U/mL and 1 × 10-4 U/mL, respectively. The proposed UDG-sensing platform was also demonstrated to work well for the UDG activity detection in cancer cells as well as UDG screening and inhibitory capability evaluation, thus showing a great potential in clinical diagnosis and biomedical research.


Asunto(s)
Técnicas Biosensibles , Uracil-ADN Glicosidasa , Sistemas CRISPR-Cas , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , ADN Nucleotidilexotransferasa , Uracil-ADN Glicosidasa/genética , Uracil-ADN Glicosidasa/metabolismo
18.
Biosens Bioelectron ; 168: 112556, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32890931

RESUMEN

We reported a CRISPR/Cas-based dual amplified sensing strategy for rapid, sensitive and selective detection of polynucleotide kinase/phosphatase (PNKP), a DNA damage repair-related biological enzyme. In this strategy, a PNKP-triggered nicking enzyme-mediated strand displacement amplification reaction was introduced to enrich the activator DNA strands for CRISPR/Cas. Such an isothermal DNA amplification step, together with subsequent activated CRISPR/Cas-catalyzed cleavage of fluorescent-labeled short-stranded DNA probes, enable synergetic signal amplification for sensitive PNKP detection. The proposed strategy showed a wide linear detection range (more than 3 orders of magnitude ranging from 1× 10-5 to 2.5 × 10-2 U/mL T4 PNKP) and a detection limit as low as 3.3 × 10-6 U/mL. It was successfully used for the PNKP activity detection in cell extracts with high fidelity and displayed great potential for enzyme inhibitor screening and inhibitory capability evaluation. This work broadens the applications of CRISPR/Cas12a-based sensors to biological enzymes and provides a way to improve the sensitivity by introducing an isothermal signal amplification step. Such an isothermal DNA amplification-CRISPR/Cas-combined biosensor design concept might expand CRISPR/Cas-based sensing systems and promote their applications in various fields such as disease diagnosis and drug screening.


Asunto(s)
Técnicas Biosensibles , Polinucleótido 5'-Hidroxil-Quinasa , Sistemas CRISPR-Cas/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Monoéster Fosfórico Hidrolasas , Polinucleótido 5'-Hidroxil-Quinasa/genética
19.
Waste Manag ; 118: 471-480, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32979778

RESUMEN

Waste polystyrene (PS) and polycarbonate (PC) are crucial components arising from mixtures of plastic products, whose recycling is significantly limited by separation efficiency. In this work, to assist the flotation separation of PC and PS, we proposed a novel modification technology of surface alkoxylation pretreatment (SAP) where PC surface reacted with glycerol and urea. The SAP could selectively transform the hydrophobic PC into hydrophilic plastic, while the PS remained its hydrophobic surface owing to the exclusion from SAP process. Benefiting from the hydrophilic PC, the separation efficiency of PS and PC could reach the maximum of 99.34% under optimum conditions (urea dosage of 5 g, pretreatment temperature of 130 °C, pretreatment time of 10 min, flotation time of 2.5 min, frother concentration of 16.5 mg/L, and airflow rate of 7.2 mL/min). The mechanism of SAP was systematically analyzed by wettability, surface morphology, molecular weight, and chemical reactions. Compared with PS plastic, the pretreated PC presented better wettability, rougher surface, and significantly reducing molecular weight. The improvement of PC hydrophilicity can be attributed to the cleavage of ester bonds on backbone chains and the introduction of hydrophilic hydroxyl groups. The effective SAP process proves that chemical recycling of waste plastic can provide a novel strategy for surface modification and flotation separation of PS and PC.


Asunto(s)
Poliestirenos , Eliminación de Residuos , Interacciones Hidrofóbicas e Hidrofílicas , Plásticos , Cemento de Policarboxilato
20.
Angew Chem Int Ed Engl ; 59(40): 17504-17510, 2020 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-32602633

RESUMEN

Amorphous iron phosphate (FePO4 ) has attracted enormous attention as a promising cathode material for sodium-ion batteries (SIBs) because of its high theoretical specific capacity and superior electrochemical reversibility. Nevertheless, the low rate performance and rapid capacity decline seriously hamper its implementation in SIBs. Herein, we demonstrate a sagacious multi-step templating approach to skillfully craft amorphous FePO4 yolk-shell nanospheres with mesoporous nanoyolks supported inside the robust porous outer nanoshells. Their unique architecture and large surface area enable these amorphous FePO4 yolk-shell nanospheres to manifest remarkable sodium storage properties with high reversible capacity, outstanding rate performance, and ultralong cycle life.

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