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1.
J Am Chem Soc ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39025790

RESUMO

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.

2.
Environ Sci Technol ; 58(27): 11869-11886, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38940189

RESUMO

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.


Assuntos
Enzimas Imobilizadas , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Porosidade , Biocatálise , Poluentes Ambientais/química
3.
J Am Chem Soc ; 146(25): 17189-17200, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864358

RESUMO

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.


Assuntos
Estabilidade Enzimática , Enzimas Imobilizadas , Interações Hidrofóbicas e Hidrofílicas , Lipase , Lipase/química , Lipase/metabolismo , Porosidade , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Estruturas Metalorgânicas/química , Hidrólise , Biocatálise
4.
Chembiochem ; : e202400339, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801661

RESUMO

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.

5.
BMC Anesthesiol ; 24(1): 90, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433227

RESUMO

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.


Assuntos
Anestésicos , Neoplasias Colorretais , Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias Gástricas , Adulto , Humanos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Sistemas Automatizados de Assistência Junto ao Leito , Aspiração Respiratória , Estudos de Coortes
6.
Angew Chem Int Ed Engl ; 63(8): e202319876, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38183367

RESUMO

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.


Assuntos
Disciplinas das Ciências Biológicas , Líquidos Iônicos , Estruturas Metalorgânicas , Polimerização , Lipase
7.
Small ; 20(22): e2308630, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38100208

RESUMO

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).

8.
J Am Chem Soc ; 146(3): 1967-1976, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38131319

RESUMO

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.


Assuntos
Hidrogênio , Catálise , Hidrogênio/química
9.
Small ; : e2308716, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072769

RESUMO

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.

10.
ACS Nano ; 17(23): 24130-24140, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38015792

RESUMO

Biomineralization is a natural process of mineral formation mediated by biomacromolecules, allowing access to hierarchical structures integrating biological, chemical, and material properties. In this contribution, we comprehensively investigate the biomineralization of zeolite imidazole frameworks (ZIFs) for one-step synthesis of an enzyme-MOF biocomposite, in terms of differential crystallization behaviors, fine microstructure of resultant ZIF biominerals, the enzyme's conformation evolution, and protective effect of ZIF mineral. We discover that the biomineralization ability is ZIF organic linker dependent and the biocatalytic function is highly related to the ZIF mineral species and their distinguishable topologies and defect structures. Importantly, a side-by-side analysis suggests that the protective effect of ZIF mineral toward the hosted enzyme is highly associated with the synergistic effect of size dimension and chemical microenvironment of the ZIF pores. This work provides important insight into the ZIF-dependent biomineralization behaviors and highlights the important role of the ZIF microstructure in its biocatalytic activity and durability, which has been underestimated previously.


Assuntos
Estruturas Metalorgânicas , Zeolitas , Estruturas Metalorgânicas/química , Zeolitas/química , Enzimas Imobilizadas/química , Biocatálise , Imidazóis/química
11.
ACS Mater Lett ; 5(9): 2408-2421, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37680545

RESUMO

High power conversion efficiencies (PCE), low energy payback time (EPBT), and low manufacturing costs render perovskite solar cells (PSCs) competitive; however, a relatively low operational stability impedes their large-scale deployment. In addition, state-of-the-art PSCs are made of expensive materials, including the organic hole transport materials (HTMs) and the noble metals used as the charge collection electrode, which induce degradation in PSCs. Thus, developing inexpensive alternatives is crucial to fostering the transition from academic research to industrial development. Combining a carbon-based electrode with an inorganic HTM has shown the highest potential and should replace noble metals and organic HTMs. In this review, we illustrate the incorporation of a carbon layer as a back contact instead of noble metals and inorganic HTMs instead of organic ones as two cornerstones for achieving optimal stability and economic viability for PSCs. We discuss the primary considerations for the selection of the absorbing layer as well as the electron-transporting layer to be compatible with the champion designs and ultimate architecture for single-junction PSCs. More studies regarding the long-term stability are still required. Using the recommended device architecture presented in this work would pave the way toward constructing low-cost and stable PSCs.

12.
Chempluschem ; 88(10): e202300352, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37624692

RESUMO

Since the discovery that Fe3 O4 nanoparticle has intrinsic natural peroxidase-like activity by Yan et al in 2007, mimicking native enzymes via nano-engineering (named as nanozyme) pays a new avenue to bypass the fragility and recyclability of natural enzymes and thus expedites the biocatalysis in multidisciplinary applications. In addition, the high programmability and structural stability attributes of nanozyme afford the ease of coupling with electromagnetic waves of different energies, providing great opportunities to construct photo-responsive nanozyme under user-defined electromagnetic waves, which is known as photo-nanozyme. In this concept, we aim to providing a summary of how electromagnetic waves with varying wavelengths can serve as external stimuli to induce or enhance the biocatalytic performance of photo-nanozymes, thereby offering fascinating functions that cannot be achieved by pristine nanozyme.


Assuntos
Nanopartículas Metálicas , Biocatálise , Nanopartículas Metálicas/química
13.
STAR Protoc ; 4(3): 102421, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37432851

RESUMO

Enzyme immobilization into porous frameworks is an emerging strategy for enhancing the stability of dynamic conformation and prolonging the lifespan of enzymes. Here, we present a protocol for a de novo mechanochemistry-guided assembly strategy for enzyme encapsulation using covalent organic frameworks. We describe steps for mechanochemical synthesis, enzyme loading measurements, and material characterizations. We then detail evaluations of biocatalytic activity and recyclability. For complete details on the use and execution of this protocol, please refer to Gao et al. (2022).1.


Assuntos
Estruturas Metalorgânicas , Porosidade
14.
Nat Commun ; 14(1): 3644, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37339954

RESUMO

Rational integration of native enzymes and nanoscaffold is an efficient means to access robust biocatalyst, yet remains on-going challenges due to the trade-off between fragile enzymes and harsh assembling conditions. Here, we report a supramolecular strategy enabling the in situ fusion of fragile enzymes into a robust porous crystal. A c2-symmetric pyrene tecton with four formic acid arms is utilized as the building block to engineer this hybrid biocatalyst. The decorated formic acid arms afford the pyrene tectons high dispersibility in minute amount of organic solvent, and permit the hydrogen-bonded linkage of discrete pyrene tectons to an extended supramolecular network around an enzyme in almost organic solvent-free aqueous solution. This hybrid biocatalyst is covered by long-range ordered pore channels, which can serve as the gating to sieve the catalytic substrate and thus enhance the biocatalytic selectivity. Given the structural integration, a supramolecular biocatalyst-based electrochemical immunosensor is developed, enabling the pg/mL detection of cancer biomarker.


Assuntos
Técnicas Biossensoriais , Hidrogênio , Imunoensaio , Formiatos
15.
Nat Protoc ; 18(7): 2032-2050, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37198321

RESUMO

Enzymes are outstanding natural catalysts with exquisite 3D structures, initiating countless life-sustaining biotransformations in living systems. The flexible structure of an enzyme, however, is highly susceptible to non-physiological environments, which greatly limits its large-scale industrial applications. Seeking suitable supports to immobilize fragile enzymes is one of the most efficient routes to ameliorate the stability problem. This protocol imparts a new bottom-up strategy for enzyme encapsulation using a hydrogen-bonded organic framework (HOF-101). In short, the surface residues of the enzyme can trigger the nucleation of HOF-101 around its surface through the hydrogen-bonded biointerface. As a result, a series of enzymes with different surface chemistries are able to be encapsulated within a highly crystalline HOF-101 scaffold, which has long-range ordered mesochannels. The details of experimental procedures are described in this protocol, which involve the encapsulating method, characterizations of materials and biocatalytic performance tests. Compared with other immobilization methods, this enzyme-triggering HOF-101 encapsulation is easy to operate and affords higher loading efficiency. The formed HOF-101 scaffold has an unambiguous structure and well-arranged mesochannels, favoring mass transfer and understanding of the biocatalytic process. It takes ~13.5 h for successful synthesis of enzyme-encapsulated HOF-101, 3-4 d for characterizations of materials and ~4 h for the biocatalytic performance tests. In addition, no specific expertise is necessary for the preparation of this biocomposite, although the high-resolution imaging requires a low-electron-dose microscope technology. This protocol can provide a useful methodology to efficiently encapsulate enzymes and design biocatalytic HOF materials.


Assuntos
Elétrons , Hidrogênio , Projetos de Pesquisa
16.
Acta Biomater ; 159: 338-352, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36669551

RESUMO

There is growing interest in the effect of innate immune silencing in "cold" tumors, which always fail in the immune checkpoint blockade monotherapy using PD-L1 monoclonal antibodies (aPD-L1). Combination of aPD-L1 with photodynamic therapy, i.e., photoimmunotherapy, is a promising strategy to improve the mono immunotherapy. Nuclear-targeting nanoparticles could elicit a type I interferon (IFN)-mediated innate immune response and reverse the immunosuppressive microenvironment for long-term immunotherapy of "cold" tumors. Photosensitizers such as zinc phthalocyanine (ZnPc) have limited ability to target the nucleus and activate innate sensing pathways to minimize tumor recurrence. Additionally, the relationship between nanoparticle size and nuclear entry capacity remains unclear. Herein, graphene quantum dots (GQDs) were employed as aPD-L1 and ZnPc carriers. Three particle sizes (200 nm, 32 nm and 5 nm) of aPD-L1/ZnPc/GQD-PEG (PZGE) were synthesized and tested. The 5 nm nanoparticles achieved the best nuclear enrichment capacity contributing to their ultrasmall size. Notably, 5 nm PZGE-based photodynamic therapy enabled an amplification of the type I IFN-mediated innate immune response and could convert "immune-cold" tumors into "immune-hot" ones. Utilizing their size advantage to target the nucleus, 5 nm nanoparticles induced DNA damage and activated the type I IFN-mediated innate immune response, subsequently promoting cytotoxic T-lymphocyte infiltration and reversing negative PD-L1 expression. Furthermore, the nanoplatform we designed is promising for the effective suppression of distant oral squamous cell carcinoma. Thus, for the first time, this study presents a size design strategy for nuclear-targeted photo-controlled immune adjuvants and the nuclear-targeted phototherapy-mediated immunomodulatory functions of type I IFN innate immune signalling for "immune-cold" tumors. STATEMENT OF SIGNIFICANCE: The potential of commonly used photosensitizers to activate innate sensing pathways for producing type I IFNs is limited due to the lack of nuclear targeting. Facilitating the nuclear-targeting of photosensitizers to enhance innate immune response and execute long-term tumor killing effect would be a promising strategy for "cold" tumor photoimmunotherapy. Herein, we report an optimal size of PZGE nanoparticles that enable the nuclear-targeting of ZnPc, which reinforces the type I IFN-mediated innate immune response, synergistically reversing "cold tumors" to "hot tumors" for effective primary and distant tumor photoimmunotherapy. This work highlights the marked efficacy of ultrasmall nuclear-located nanocarriers and offers new insight into "immune-cold tumors" via prominent innate immune activation mediated by nuclear-targeting photoimmunotherapy.


Assuntos
Carcinoma de Células Escamosas , Interferon Tipo I , Neoplasias Bucais , Neoplasias , Humanos , Antígeno B7-H1 , Linhagem Celular Tumoral , Recidiva Local de Neoplasia , Neoplasias/terapia , Fármacos Fotossensibilizantes , Fototerapia , Microambiente Tumoral , Imunoterapia
17.
Angew Chem Int Ed Engl ; 62(13): e202218661, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36719177

RESUMO

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.


Assuntos
Hidrogênio , Oxirredutases , Catálise , Ligação de Hidrogênio , Monoéster Fosfórico Hidrolases
18.
Anal Chem ; 94(41): 14385-14393, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36205458

RESUMO

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.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Alginatos , Glucose , Glucose Oxidase/química , Hidrogéis , Estruturas Metalorgânicas/química , Peroxidases , Smartphone
19.
Chem Commun (Camb) ; 58(91): 12720-12723, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36314354

RESUMO

Herein, we develop a hierarchically mesoporous cerium metal-organic framework (Ce-HMMOF) nanozyme with enhanced ALP-mimicking activity for the naked-eye detection of phosphorylated biomarkers. The long-range ordered mesochannels (9.18 nm) throughout the Ce-HMMOF promote both the mass transfer and the accessibility of interior active sites, permitting the rapid and sensitive sensing of phosphorylated biomarkers through ALP-like biocatalysis. This work provides a new insight into the engineering of highly active nanozymes for disease-associated biomarker screening and diagnosis.


Assuntos
Cério , Estruturas Metalorgânicas , Fosfatase Alcalina/metabolismo , Estruturas Metalorgânicas/química , Cério/química , Biocatálise , Biomarcadores
20.
JACS Au ; 2(9): 2048-2058, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36186550

RESUMO

A diabetic wound causes thousands of infections or deaths around the world each year, and its healing remains a critical challenge because of the ease of multidrug-resistant (MDR) bacterial infection, as well as the intrinsic hyperglycemic and hypoxia microenvironment that inhibits the therapeutic efficiency. Herein, we pioneer the design of a photobiocatalytic cascade nanoreactor via spatially organizing the biocatalysts and photocatalysts utilizing a hydrogen-bonded organic framework (HOF) scaffold for diabetic wound therapy. The HOF scaffold enables it to disperse and stabilize the host cargos, and the formed long-range-ordered mesochannels also facilitate the mass transfer that enhances the cascade activity. This integrated HOF nanoreactor allows the continuous conversion of overexpressed glucose and H2O2 into toxic reactive oxygen species by the photobiocatalytic cascade. As a result, it readily reverses the microenvironment of the diabetes wound and exhibits an extraordinary capacity for wound healing through synergistic photodynamic therapy. This work describes the first example of constructing an all-in-one HOF bioreactor for antimicrobial diabetes wound treatment and showcases the promise of combined biocatalysis and photocatalysis achieved by using an HOF scaffold in biomedicine applications.

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