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1.
J Am Chem Soc ; 146(30): 21025-21033, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39025790

RESUMEN

Artificial photosynthesis represents a sustainable strategy for accessing high-value chemicals; however, the conversion efficiency is significantly limited by its difficulty in the cycle of coenzymes such as NADH. In this study, we report a series of isostructural triazine covalent organic frameworks (COFs) and explore their N-substituted microenvironment-dependent photocatalytic activity for NADH regeneration. We discovered that the rational alteration of N-heterocyclic species, which are linked to the triazine center through an imine linkage, can significantly regulate both the electron band structure and planarity of a COF layer. This results in different separation efficiencies of the photoinduced electron-hole pairs and electron transfer behavior within and between individual layers. The optimal COF catalyst herein achieves an NADH regeneration capacity of 89% within 20 min, outperforming most of the reported nanomaterial photocatalysts. Based on this, an artificial photosynthesis system is constructed for the green synthesis of a high-value compound, L-glutamate, and its conversion efficiency significantly surpasses the enzymatic approach without the NADH photocatalytic cycle. This work offers new insights into the coenzyme regeneration by means of regulating the distal heterocyclic microenvironment of a COF skeleton, holding great potential for the green photosynthesis of important chemicals.


Asunto(s)
Estructuras Metalorgánicas , Triazinas , Triazinas/química , Catálisis , Estructuras Metalorgánicas/química , NAD/química , NAD/metabolismo , Procesos Fotoquímicos , Estructura Molecular , Coenzimas/química , Coenzimas/metabolismo , Fotosíntesis
2.
J Am Chem Soc ; 146(3): 1967-1976, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38131319

RESUMEN

Engineering nanotraps to immobilize fragile enzymes provides new insights into designing stable and sustainable biocatalysts. However, the trade-off between activity and stability remains a long-standing challenge due to the inevitable diffusion barrier set up by nanocarriers. Herein, we report a synergetic interfacial activation strategy by virtue of hydrogen-bonded supramolecular encapsulation. The pore wall of the nanotrap, in which the enzyme is encapsulated, is modified with methyl struts in an atomically precise position. This well-designed supramolecular pore results in a synergism of hydrogen-bonded and hydrophobic interactions with the hosted enzyme, and it can modulate the catalytic center of the enzyme into a favorable configuration with high substrate accessibility and binding capability, which shows up to a 4.4-fold reaction rate and 4.9-fold conversion enhancements compared to free enzymes. This work sheds new light on the interfacial activation of enzymes using supramolecular engineering and also showcases the feasibility of interfacial assembly to access hierarchical biocatalysts featuring high activity and stability simultaneously.


Asunto(s)
Hidrógeno , Catálisis , Hidrógeno/química
3.
J Am Chem Soc ; 146(25): 17189-17200, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38864358

RESUMEN

Spatial immobilization of fragile enzymes using a nanocarrier is an efficient means to design heterogeneous biocatalysts, presenting superior stability and recyclability to pristine enzymes. An immobilized enzyme, however, usually compromises its catalytic activity because of inevasible mass transfer issues and the unfavorable conformation changes in a confined environment. Here, we describe a synergetic metal-organic framework pore-engineering strategy to trap lipase (an important hydrolase), which confers lipase-boosted stability and activity simultaneously. The hierarchically porous NU-1003, featuring interconnected mesopore and micropore channels, is precisely modified by chain-adjustable fatty acids on its mesopore channel, into which lipase is trapped. The interconnected pore structure ensures efficient communication between trapped lipase and exterior media, while the fatty acid-mediated hydrophobic pore can activate the opening conformation of lipase by interfacial interaction. Such dual pore compartmentalization and hydrophobization activation effects render the catalytic center of trapped lipase highly accessible, resulting in 1.57-fold and 2.46-fold activities as native lipase on ester hydrolysis and enantioselective catalysis. In addition, the feasibility of these heterogeneous biocatalysts for kinetic resolution of enantiomer is also validated, showing much higher efficiency than native lipase.


Asunto(s)
Estabilidad de Enzimas , Enzimas Inmovilizadas , Interacciones Hidrofóbicas e Hidrofílicas , Lipasa , Lipasa/química , Lipasa/metabolismo , Porosidad , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Estructuras Metalorgánicas/química , Hidrólisis , Biocatálisis
4.
Small ; 20(22): e2308630, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38100208

RESUMEN

Sodium-ion hybrid capacitors (SIHCs) have attracted much attention due to integrating the high energy density of battery and high out power of supercapacitors. However, rapid Na+ diffusion kinetics in cathode is counterbalanced with sluggish anode, hindering the further advancement and commercialization of SIHCs. Here, aiming at conversion-type metal sulfide anode, taking typical VS2 as an example, a comprehensive regulation of nanostructure and electronic properties through NH4 + pre-intercalation and Mo-doping VS2 (Mo-NVS2) is reported. It is demonstrated that NH4 + pre-intercalation can enlarge the interplanar spacing and Mo-doping can induce interlayer defects and sulfur vacancies that are favorable to construct new ion transport channels, thus resulting in significantly enhanced Na+ diffusion kinetics and pseudocapacitance. Density functional theory calculations further reveal that the introduction of NH4 + and Mo-doping enhances the electronic conductivity, lowers the diffusion energy barrier of Na+, and produces stronger d-p hybridization to promote conversion kinetics of Na+ intercalation intermediates. Consequently, Mo-NVS2 delivers a record-high reversible capacity of 453 mAh g-1 at 3 A g-1 and an ultra-stable cycle life of over 20 000 cycles. The assembled SIHCs achieve impressive energy density/power density of 98 Wh kg-1/11.84 kW kg-1, ultralong cycling life of over 15000 cycles, and very low self-discharge rate (0.84 mV h-1).

5.
Chembiochem ; : e202400339, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801661

RESUMEN

Utilizing covalent organic frameworks (COFs) as porous supports to encapsulate enzyme represents an advanced strategy for constructing COFs biocatalysts, which has inspired numerous interests across various applications. As the structural advantages including ultrastable covalent-bonded linkage, tailorable pore structure, and metal-free biocompatibility, the resultant enzyme-COFs biocatalysts showcase functional enhancement in catalytic activity, chemical stability, long-term durability, and recyclability. This Concept describes the recent advances in the methodological strategies for engineering the COFs biocatalysts, with specific emphasis on the pore entrapment and in situ encapsulation strategies. The structural advantages of the COFs hybrid biocatalysts for organic synthesis, environment- and energy-associated applications are also canvassed. Additionally, the remaining challenges and the forward-looking directions in this field are also discussed. We believe that this Concept can offer useful methodological guidance for developing active and robust COFs biocatalysts.

6.
Environ Sci Technol ; 58(27): 11869-11886, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38940189

RESUMEN

Developing efficient technologies to eliminate or degrade contaminants is paramount for environmental protection. Biocatalytic decontamination offers distinct advantages in terms of selectivity and efficiency; however, it still remains challenging when applied in complex environmental matrices. The main challenge originates from the instability and difficult-to-separate attributes of fragile enzymes, which also results in issues of compromised activity, poor reusability, low cost-effectiveness, etc. One viable solution to harness biocatalysis in complex environments is known as enzyme immobilization, where a flexible enzyme is tightly fixed in a solid carrier. In the case where a reticular crystal is utilized as the support, it is feasible to engineer next-generation biohybrid catalysts functional in complicated environmental media. This can be interpreted by three aspects: (1) the highly crystalline skeleton can shield the immobilized enzyme against external stressors. (2) The porous network ensures the high accessibility of the interior enzyme for catalytic decontamination. And (3) the adjustable and unambiguous structure of the reticular framework favors in-depth understanding of the interfacial interaction between the framework and enzyme, which can in turn guide us in designing highly active biocomposites. This Review aims to introduce this emerging biocatalysis technology for environmental decontamination involving pollutant degradation and greenhouse gas (carbon dioxide) conversion, with emphasis on the enzyme immobilization protocols and diverse catalysis principles including single enzyme catalysis, catalysis involving enzyme cascades, and photoenzyme-coupled catalysis. Additionally, the remaining challenges and forward-looking directions in this field are discussed. We believe that this Review may offer a useful biocatalytic technology to contribute to environmental decontamination in a green and sustainable manner and will inspire more researchers at the intersection of the environment science, biochemistry, and materials science communities to co-solve environmental problems.


Asunto(s)
Enzimas Inmovilizadas , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Porosidad , Biocatálisis , Contaminantes Ambientales/química
7.
BMC Anesthesiol ; 24(1): 90, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38433227

RESUMEN

BACKGROUND: Pulmonary aspiration of gastric contents is a serious perioperative complication. Patients with gastric cancer may experience delayed gastric emptying. However, the role of qualitative and quantitative gastric ultrasound assessments in this patient population before anesthesia induction has not yet been determined. METHODS: Adult patients with gastrointestinal cancer were recruited and examined using gastric point-of-care ultrasound (POCUS) before anesthetic induction from March 2023 to August 2023 in a tertiary cancer center. Three hundred patients with gastric cancer were conducted with POCUS prior to induction, and three hundred patients with colorectal cancer were included as controls. The cross-sectional area (CSA) of the gastric antrum and gastric volumes (GV) were measured and calculated. We determined the nature of the gastric contents and classified the antrum using a 3-point grading system. A ratio of GV to body weight > 1.5mL/Kg was defined as a high risk of aspiration. RESULTS: In patients with gastric cancer, 70 patients were classified as grade 2 (23%, including 6 patients with solid gastric contents) and 63 patients (21%) were identified as having a high risk of aspiration. Whereas in patients with colorectal cancer, only 11 patients were classified as grade 2 (3.7%), and 27 patients (9.7%) were identified as having a high risk of aspiration. A larger tumor size (OR:1.169, 95% CI 1.045-1.307, P = 0.006), tumor located in antrum (OR:2.304, 95% CI 1.169-4.539,P = 0.016), gastrointestinal obstruction (OR:21.633, 95% CI 4.199-111.443, P < 0.0001) and more lymph node metastasis (OR:2.261, 95% CI 1.062-4.812, P = 0.034) were found to be positively while tumor site at cardia (OR:0.096, 95% CI 0.019-0.464, P = 0.004) was negatively associated with high aspiration risk in patients with gastric cancer. CONCLUSION: The Gastric POCUS prior to induction provides an assessment of the status of gastric emptying and can identify the patients at high risk of aspiration, especially those with gastric cancer. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( www.chictr.org.cn ) identifier: ChiCTR2300069242; registered 10 March 2023.


Asunto(s)
Anestésicos , Neoplasias Colorrectales , Procedimientos Quirúrgicos del Sistema Digestivo , Neoplasias Gástricas , Adulto , Humanos , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/cirugía , Sistemas de Atención de Punto , Aspiración Respiratoria , Estudios de Cohortes
8.
Proc Natl Acad Sci U S A ; 118(16)2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33853952

RESUMEN

Photosynthesis of hydrogen peroxide (H2O2) in ambient conditions remains neither cost effective nor environmentally friendly enough because of the rapid charge recombination. Here, a photocatalytic rate of as high as 114 µmol⋅g-1⋅h-1 for the production of H2O2 in pure water and open air is achieved by using a Z-scheme heterojunction, which outperforms almost all reported photocatalysts under the same conditions. An extensive study at the atomic level demonstrates that Z-scheme electron transfer is realized by improving the photoresponse of the oxidation semiconductor under visible light, when the difference between the Fermi levels of the two constituent semiconductors is not sufficiently large. Moreover, it is verified that a type II electron transfer pathway can be converted to the desired Z-scheme pathway by tuning the excitation wavelengths. This study demonstrates a feasible strategy for developing efficient Z-scheme photocatalysts by regulating photoresponses.

9.
Angew Chem Int Ed Engl ; 63(8): e202319876, 2024 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-38183367

RESUMEN

Utilizing covalent organic framework (COF) as a hypotoxic and porous scaffold to encapsulate enzyme (enzyme@COF) has inspired numerous interests at the intersection of chemistry, materials, and biological science. In this study, we report a convenient scheme for one-step, aqueous-phase synthesis of highly crystalline enzyme@COF biocatalysts. This facile approach relies on an ionic liquid (2 µL of imidazolium ionic liquid)-mediated dynamic polymerization mechanism, which can facilitate the in situ assembly of enzyme@COF under mild conditions. This green strategy is adaptive to synthesize different biocatalysts with highly crystalline COF "exoskeleton", as well evidenced by the low-dose cryo-EM and other characterizations. Attributing to the rigorous sieving effect of crystalline COF pore, the hosted lipase shows non-native selectivity for aliphatic acid hydrolysis. In addition, the highly crystalline linkage affords COF "exoskeleton" with higher photocatalytic activity for in situ production of H2 O2 , enabling us to construct a self-cascading photo-enzyme coupled reactor for pollutants degradation, with a 2.63-fold degradation rate as the poorly crystalline photo-enzyme reactor. This work showcases the great potentials of employing green and trace amounts of ionic liquid for one-step synthesis of crystalline enzyme@COF biocatalysts, and emphasizes the feasibility of diversifying enzyme functions by integrating the reticular chemistry of a COF.


Asunto(s)
Disciplinas de las Ciencias Biológicas , Líquidos Iónicos , Estructuras Metalorgánicas , Polimerizacion , Lipasa
10.
Small ; : e2308716, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-38072769

RESUMEN

The selective quantification of copper ions (Cu2+ ) in biosamples holds great importance for disease diagnosis, treatment, and prognosis since the Cu2+ level is closely associated with the physiological state of the human body. While it remains a long-term challenge due to the extremely low level of free Cu2+ and the potential interference by the complex matrices. Here, a pore-engineered hydrogen-bonded organic framework (HOF) fluorosensor is constructed enabling the ultrasensitive and highly selective detection of free Cu2+ . Attributing to atomically precise functionalization of active amino "arm" within the HOF pores and the periodic π-conjugated skeleton, this porous HOF fluorosensor affords high affinity toward Cu2+ through double copper-nitrogen (Cu─N) coordination interactions, resulting in specific fluorescence quenching of the HOF as compared with a series of substances ranging from other metal ions, metabolites, amino acids to proteins. Such superior fluorescence quenching effect endows the Cu2+ quantification by this new HOF sensor with a wide linearity of 50-20 000 nm, a low detection limit of 10 nm, and good recoveries (89.5%-115%) in human serum matrices, outperforming most of the reported approaches. This work highlights the practicability of hydrogen-bonded supramolecular engineering for designing facile and ultrasensitive biosensors for clinical free Cu2+ determination.

11.
Chem Soc Rev ; 51(15): 6824-6863, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35852480

RESUMEN

Enzymes are a class of natural catalysts with high efficiency, specificity, and selectivity unmatched by their synthetic counterparts and dictate a myriad of reactions that constitute various cascades in living cells. The development of suitable supports is significant for the immobilization of structurally flexible enzymes, enabling biomimetic transformation in the extracellular environment. Accordingly, porous organic frameworks, including metal organic frameworks (MOFs), covalent organic frameworks (COFs) and hydrogen-bonded organic frameworks (HOFs), have emerged as ideal supports for the immobilization of enzymes because of their structural features including ultrahigh surface area, tailorable porosity, and versatile framework compositions. Specially, organic framework-encased enzymes have shown significant enhancement in stability and reusability, and their tailorable pore opening provides a gatekeeper-like effect for guest sieving, which is beneficial for mimicking intracellular biocatalysis processes. This immobilization technique brings new insight into the development of next-generation enzyme materials and shows huge potential in healthcare applications, such as biomarker diagnosis, biostorage, and cancer and antibacterial therapies. In this review, we describe the state-of-the-art strategies for the structural immobilization of enzymes using the well-explored MOFs and burgeoning COFs and HOFs as scaffolds, with special emphasis on how these porous framework-confined technologies can provide a favorable microenvironment for mimicking natural biocatalysis. Subsequently, advanced characterization techniques for enzyme conformation, the effect of the confined microenvironment on the activity of enzymes, and the emerging healthcare applications will be surveyed.


Asunto(s)
Estructuras Metalorgánicas , Catálisis , Atención a la Salud , Enzimas Inmovilizadas/química , Hidrógeno , Estructuras Metalorgánicas/química , Porosidad
12.
Angew Chem Int Ed Engl ; 62(13): e202218661, 2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36719177

RESUMEN

Mimicking the bioactivity of native enzymes through synthetic chemistry is an efficient means to advance the biocatalysts in a cell-free environment, however, remains long-standing challenges. Herein, we utilize structurally explicit hydrogen-bonded organic frameworks (HOFs) to mimic photo-responsive oxidase, and uncover the important role of pore environments on mediating oxidase-like activity by means of constructing isostructural HOFs. We discover that the HOF pore with suitable geometry can stabilize and spatially organize the catalytic substrate into a favorable catalytic route, as with the function of the native enzyme pocket. Based on the desirable photo-responsive oxidase-like activity, a visual and sensitive HOFs biosensor is established for the detection of phosphatase, an important biomarker of skeletal and hepatobiliary diseases. This work demonstrates that the pore environments significantly influence the nanozymes' activity in addition to the active center.


Asunto(s)
Hidrógeno , Oxidorreductasas , Catálisis , Enlace de Hidrógeno , Monoéster Fosfórico Hidrolasas
13.
Anal Chem ; 94(41): 14385-14393, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36205458

RESUMEN

Enzymes featuring high catalytic efficiency and selectivity have been widely used as the sensing element in analytical chemistry. However, the structural fragility and poor machinability of an enzyme significantly limit its practicability in biosensors. Herein, we develop a robust and sensitive hybrid biosensor by means of co-encapsulating enzymes into a defective metal-organic framework (MOF), followed by a double-crosslinked alginate gelatinization. The defective MOF encapsulation can enhance the stability of enzymes, yet well preserve their biocatalytic function, while the alginate gelatinization allows the MOF biohybrid high stretchability and mechanical strength, which facilitates the integration of a bead-, fiber-, and sheet-like portable biosensor. In this work, the enzymes consisting of glucose oxidase and peroxidase are co-encapsulated into this MOF hydrogel, and it can efficiently convert glucose into a blue-violet product through the biocatalytic cascade of encapsulated enzymes, enabling the colorimetric biosensing of glucose on a miniaturized MOF hydrogel when coupling with a smartphone. Interestingly, this MOF biohybrid hydrogel outputs a stronger sensing signal than the free biohybrid powders, attributed to the catalytic product-accumulated effect of the highly hydrophilic microenvironment of the hydrogel. As a result, this portable biosensor can sensitively and selectively sense glucose with a linear range from 0.05 to 4 mM. Importantly, both the hydrophilic hydrogel and MOF "armor" endow enzymes with high durability, and its sensing activity was well-maintained even after placing the biosensor at room temperature for 30 d. We believe that this MOF biohybrid hydrogel has huge potential for the engineering of next-generation portable biosensors.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Alginatos , Glucosa , Glucosa Oxidasa/química , Hidrogeles , Estructuras Metalorgánicas/química , Peroxidasas , Teléfono Inteligente
14.
Chembiochem ; 23(10): e202100567, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35025113

RESUMEN

The highly efficient and specific catalysis of enzymes allows them to recognize a myriad of substrates, which enables biosensing. However, the fragility of natural enzymes severely restricts their practical applications. Metal-organic frameworks (MOFs) with porous networks and attractive functions have been intelligently employed as supports to encase enzymes and protect them against harsh environments. More importantly, customizable construction and composition affords the intrinsic enzyme-like activity of some MOFs (known as nanozymes), which provides an alternative route for the construction of robust enzyme mimics. This review will introduce the concept of these biocatalytic MOFs, with special emphasis on how biocatalytic processes that operate in these materials can reverse the plight of native enzyme-based biosensing. In addition, the present challenges and future outlooks in this research field are briefly discussed.


Asunto(s)
Estructuras Metalorgánicas , Biocatálisis , Catálisis , Estructuras Metalorgánicas/química , Porosidad
15.
Chemistry ; 28(34): e202200074, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35404521

RESUMEN

Multienzyme biocatalytic cascade systems (MBCS) have attracted widespread research in the field of biosensing due to selective substrate transformations and signal amplification function. However, the poor stability of enzymes significantly restricts their effectiveness in practical applications. The spatial organization of MBCS within porous organic frameworks (POFs), such as metal-organic frameworks, covalent organic frameworks, and hydrogen-bonded organic frameworks, is regarded as a promising strategy to overcome these challenges. This advanced biotechnology sets up a POFs microenvironment for enzymes immobilization, and thus make it possible to shield the enzyme from the external stimulus by POFs-guided structural confinement. Simultaneously, the tailorable porous structure of POFs shell allows for the selective transport of substrates into interior enzymes, thereby accelerating the sensing process. Herein, we present the concept of this POFs-confined MBCS, wherein enzymes were completely encapsulated into, rather than adsorption onto, the POFs. We highlight the new strategies for MBCS spatial organization through rational POFs support, and describe how this new bio-nanosystem that integrates framework and enzymes functions can be designed as a versatile biosensing platform. In addition, the challenges and outlooks are also discussed.


Asunto(s)
Estructuras Metalorgánicas , Adsorción , Biocatálisis , Enzimas Inmovilizadas/química , Estructuras Metalorgánicas/química , Porosidad
16.
Bioorg Chem ; 119: 105494, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34836643

RESUMEN

Both HIV and DENV are serious threats to human life, health and social economy today. So far, no vaccine for either HIV or DENV has been developed successfully. The research on anti-HIV or DENV drugs is still of great significance. In this study we developed a series of novel 2-Aryl-1H-pyrazole-S-DABOs with C6-strucutral optimizations as potent NNRTIs, among which, 8 compounds had low cytotoxicity and EC50 values in the range of 0.0508 âˆ¼ 0.0966 µM, and their selectivity index was SI > 1415 âˆ¼ 3940. In particular, two compounds 4a and 4b were identified to have good inhibitory effects on DENV of four serotypes. The EC50 of compound 4a and 4b against DENV-II (13.2 µM and 9.23 µM, respectively) were better than that of the positive control ribavirin (EC50 = 40.78 µM). In addition, the effect of C-6 substituents on the anti-HIV or anti-DENV activity of these compounds was also discussed.


Asunto(s)
Antivirales/farmacología , Virus del Dengue/efectos de los fármacos , VIH-1/efectos de los fármacos , Pirazoles/farmacología , Antivirales/síntesis química , Antivirales/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Relación Estructura-Actividad
17.
Anal Chem ; 93(41): 13981-13989, 2021 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-34605631

RESUMEN

Nanozymes are of particular interest due to their enzyme-mimicking activity and high stability that are favorable in biomedical sensing and immunoassays. In this work, we report a highly specific N-doped nanozyme through pyrolysis of framework-confined bovine serum albumin (BSA). This strategy allows one to translate the low-cost and featureless BSA into a highly active enzyme mimic. The obtained carbon nanozyme (denoted as HBF-1-C800) displays 3- to 7-fold enhancement on peroxidase (POD) activity compared with the conventional carbon nanozymes and also shows ca. 5-fold activity enhancement compared to the reported N-doping graphene. Such excellent POD activity originates from high N-doping efficiency, protein-induced defective sites, and the intrinsic porous structure of HBF-1-C800, which provides abundantly accessible active sites and accelerates substrate diffusion simultaneously. Importantly, the HBF-1-C800 nanozyme has highly specific POD activity and also enables resistance to several harsh conditions that should denature natural enzymes. These features allow it with high accuracy, stability, and sensitivity for biosensing applications. Moreover, HBF-1-C800 has been designed as a promising platform for colorimetric biosensing of several biomarkers including H2O2, glutathione, and glucose, with wide linear ranges and low limits of detection that are satisfied with the disease diagnosis.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , Biomarcadores , Colorimetría , Hidrógeno , Peróxido de Hidrógeno
18.
Anesthesiology ; 135(3): 419-432, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34192298

RESUMEN

BACKGROUND: Regional anesthesia and analgesia reduce the stress response to surgery and decrease the need for volatile anesthesia and opioids, thereby preserving cancer-specific immune defenses. This study therefore tested the primary hypothesis that combining epidural anesthesia-analgesia with general anesthesia improves recurrence-free survival after lung cancer surgery. METHODS: Adults scheduled for video-assisted thoracoscopic lung cancer resections were randomized 1:1 to general anesthesia and intravenous opioid analgesia or combined epidural-general anesthesia and epidural analgesia. The primary outcome was recurrence-free survival (time from surgery to the earliest date of recurrence/metastasis or all-cause death). Secondary outcomes included overall survival (time from surgery to all-cause death) and cancer-specific survival (time from surgery to cancer-specific death). Long-term outcome assessors were blinded to treatment. RESULTS: Between May 2015 and November 2017, 400 patients were enrolled and randomized to general anesthesia alone (n = 200) or combined epidural-general anesthesia (n = 200). All were included in the analysis. The median follow-up duration was 32 months (interquartile range, 24 to 48). Recurrence-free survival was similar in each group, with 54 events (27%) with general anesthesia alone versus 48 events (24%) with combined epidural-general anesthesia (adjusted hazard ratio, 0.90; 95% CI, 0.60 to 1.35; P = 0.608). Overall survival was also similar with 25 events (13%) versus 31 (16%; adjusted hazard ratio, 1.12; 95% CI, 0.64 to 1.96; P = 0.697). There was also no significant difference in cancer-specific survival with 24 events (12%) versus 29 (15%; adjusted hazard ratio, 1.08; 95% CI, 0.61 to 1.91; P = 0.802). Patients assigned to combined epidural-general had more intraoperative hypotension: 94 patients (47%) versus 121 (61%; relative risk, 1.29; 95% CI, 1.07 to 1.55; P = 0.007). CONCLUSIONS: Epidural anesthesia-analgesia for major lung cancer surgery did not improve recurrence-free, overall, or cancer-specific survival compared with general anesthesia alone, although the CI included both substantial benefit and harm.


Asunto(s)
Analgesia Epidural/métodos , Anestesia Epidural/métodos , Neoplasias Pulmonares/cirugía , Dolor Postoperatorio/prevención & control , Cirugía Torácica Asistida por Video/efectos adversos , Anciano , Analgesia Epidural/mortalidad , Analgésicos Opioides/administración & dosificación , Anestesia Epidural/mortalidad , Anestesia General/métodos , Anestesia General/mortalidad , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/mortalidad , Cirugía Torácica Asistida por Video/métodos
19.
Angew Chem Int Ed Engl ; 60(44): 23608-23613, 2021 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-34459532

RESUMEN

Herein, we report the first example of using mesoporous hydrogen-bonded organic frameworks (MHOFs) as the protecting scaffold to organize a biocatalytic cascade. The confined microenvironment of MHOFs has robust and large transport channels, allowing the efficient transport of a wide range of biocatalytic substrates. This new MHOF-confined cascade system shows superior activity, extended scope of catalytic substrates, and ultrahigh stability that enables the operation of complex chemical transformations in a porous carrier. In addition, the advantages of MHOF-confined cascades system for point-of-care biosensing are also demonstrated. This study highlights the advantages of HOFs as scaffold for multiple enzyme assemblies, which has huge potential for mimicking complex cellular transformation networks in a controllable manner.


Asunto(s)
Técnicas Biosensibles , Glucosa Oxidasa/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Imidazoles/metabolismo , Sistemas de Atención de Punto , Zeolitas/metabolismo , Biocatálisis , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Glucosa Oxidasa/química , Peroxidasa de Rábano Silvestre/química , Enlace de Hidrógeno , Imidazoles/química , Tamaño de la Partícula , Porosidad , Propiedades de Superficie , Zeolitas/química
20.
Anal Chem ; 92(23): 15550-15557, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33166109

RESUMEN

The photoluminescent (PL) properties of lanthanide metal-organic frameworks (Ln-MOFs) are intrinsically subtle to water molecules, which remains the major challenge that severely limits their applications as fluorescent probes in aqueous samples. Herein novel composite fluorescent probes were prepared by growing Ln-MOFs (Tb-MOF, Eu-MOF, and Tb/Eu-MOF) on carboxylated porous graphene oxide (PGO-COOH). The 3D thorny composites presented significantly longer fluorescent lifetimes and higher quantum yields than that of the bare Ln-MOFs and exhibited long-term PL stabilities in aqueous samples up to 15 days. The stable and improved PL properties demonstrated that the highly hybrid composite structures protected the MOF components from the adverse effects of water. Furthermore, the unexpected antenna effect of the PGO-COOH substrate on Ln3+ was supposed to be another reason for the improved PL properties. The composites present ultralow detection limits as low as 5.6 nM for 2,4-dinitrotoluene and 2.3 nM for dipicolinic acid as turn-off and ratiometric fluorescent probes, respectively, which was attributed to the incoporation of PGO-COOH that dramatically enahnced inner filter effects and effectively protected the energy transfer process in the MOF components from the interference of the surrounding water. This work presents an effective strategy for creating ultrasensitive and stable fluorescent probes based on Ln-MOFs for applications in aqueous samples.

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