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1.
Angew Chem Int Ed Engl ; 63(19): e202316717, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38477147

RESUMO

The electrolytes for lithium metal batteries (LMBs) are plagued by a low Li+ transference number (T+) of conventional lithium salts and inability to form a stable solid electrolyte interphase (SEI). Here, we synthesized a self-folded lithium salt, lithium 2-[2-(2-methoxy ethoxy)ethoxy]ethanesulfonyl(trifluoromethanesulfonyl) imide (LiETFSI), and comparatively studied with its structure analogue, lithium 1,1,1-trifluoro-N-[2-[2-(2-methoxyethoxy)ethoxy)]ethyl]methanesulfonamide (LiFEA). The special anion chemistry imparts the following new characteristics: i) In both LiFEA and LiETFSI, the ethylene oxide moiety efficiently captures Li+, resulting in a self-folded structure and high T+ around 0.8. ii) For LiFEA, a Li-N bond (2.069 Å) is revealed by single crystal X-ray diffraction, indicating that the FEA anion possesses a high donor number (DN) and thus an intensive interphase "self-cleaning" function for an ultra-thin and compact SEI. iii) Starting from LiFEA, an electron-withdrawing sulfone group is introduced near the N atom. The distance of Li-N is tuned from 2.069 Šin LiFEA to 4.367 Šin LiETFSI. This alteration enhances ionic separation, achieves a more balanced DN, and tunes the self-cleaning intensity for a reinforced SEI. Consequently, the fast charging/discharging capability of LMBs is progressively improved. This rationally tuned anion chemistry reshapes the interactions among Li+, anions, and solvents, presenting new prospects for advanced LMBs.

2.
J Colloid Interface Sci ; 663: 909-918, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447405

RESUMO

Peroxymonosulfate (PMS) is widely employed to generate oxygen-containing reactive species for ciprofloxacin (CIP) degradation. Herein, cobalt oxyhydroxide @activated carbon (CoOOH@AC) was synthesized via a wet chemical sedimentation method to activate PMS for degradation of CIP. The result suggested AC can support the vertical growth of CoOOH nanosheets to expose high-activity Co-contained edges, possessing efficient PMS activation and degradation activity and catalytic stability. In the presence of 3.0 mg of optimal CoOOH@AC and 2 mM PMS, 96.8 % of CIP was degraded within 10 min, approximately 11.6 and 9.97 times greater than those of CoOOH/PMS and AC/PMS systems. Notably, it was disclosed that the optimal CoOOH@AC/PMS system still exhibited efficient catalytic performance in a wide pH range, different organics and common co-existing ions. Quenching experiments and electron paramagnetic resonance indicated that both radical and non-radical processes contributed to the degradation of CIP, with 1O2 and direct electron transfer accounting for the non-radical pathway and SO4•- and •OH serving as the main radical active species. Finally, possible CIP degradation pathways were proposed based on high-performance liquid chromatography-mass spectrometry. This study provided an alternate method for wastewater treatment based on PMS catalyzed by cobalt-based hydroxide.


Assuntos
Carvão Vegetal , Ciprofloxacina , Hidróxidos , Óxidos , Ciprofloxacina/química , Peróxidos/química , Cobalto/química , Espécies Reativas de Oxigênio
3.
BMC Bioinformatics ; 24(1): 410, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37904080

RESUMO

LncRNA-protein interactions are ubiquitous in organisms and play a crucial role in a variety of biological processes and complex diseases. Many computational methods have been reported for lncRNA-protein interaction prediction. However, the experimental techniques to detect lncRNA-protein interactions are laborious and time-consuming. Therefore, to address this challenge, this paper proposes a reweighting boosting feature selection (RBFS) method model to select key features. Specially, a reweighted apporach can adjust the contribution of each observational samples to learning model fitting; let higher weights are given more influence samples than those with lower weights. Feature selection with boosting can efficiently rank to iterate over important features to obtain the optimal feature subset. Besides, in the experiments, the RBFS method is applied to the prediction of lncRNA-protein interactions. The experimental results demonstrate that our method achieves higher accuracy and less redundancy with fewer features.


Assuntos
RNA Longo não Codificante , RNA Longo não Codificante/genética , Biologia Computacional/métodos
4.
ACS Nano ; 17(17): 17169-17179, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37655688

RESUMO

The low reversibility of Li deposition/stripping in conventional carbonate electrolytes hinders the development of lithium metal batteries. Herein, we proposed a combination of solvents with a moderate donor number (DN) and LiNO3 as the sole salt, which has rarely been attempted due to its low solubility or dissociation degree in common solvents. It is found that the DN value of solvents is highly correlated to the reversibility of Li deposition behavior when LiNO3 is applied as the sole salt. The combination of LiNO3 and solvents with moderate DN behaves like a quasi-concentrated electrolyte even at a common or moderate concentration, while neither the solvents with poor solubility and low dissociation for LiNO3 (which usually corresponds to a low DN) nor the solvents with high dissociation for LiNO3 (which usually corresponds to an overly high DN) can achieve a high reversibility for low conductivity or excessive solvent decomposition. As a result, a Coulombic efficiency as high as 99.6% for Li deposition/stripping is achieved with the optimized combination. We believe this work will give a better understanding of the role of anions and solvents in the regulation of the solvation structure, and DN can be utilized as an important guideline to sieve suitable solvents for LiNO3 as the main salt to exhibit intriguing properties beyond traditional cognition.

5.
ACS Nano ; 17(17): 17527-17535, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37578399

RESUMO

Li metal is regarded as the most promising battery anode to boost energy density. However, being faced with the hostile compatibility between the Li anode and traditional carbonate electrolyte, its large-scale industrialization has been in a distressing circumstance due to severe dendrite growth caused by unsatisfying solid electrolyte interphase (SEI). With this regard, accurate control over the composition of the SEI is urgently desired to tackle the electrochemical and mechanical instability at the electrolyte/anode interface. Herein, we report a rationally designed fluorinated carbamate-based electrolyte employing LiNO3 as one of the main salts to induce the preferable anion decomposition to achieve a homogeneous and inorganic (LiF, Li3N, Li2O)-rich SEI. Thus, this electrolyte achieves a high Coulombic efficiency of 99% of the Li metal anode, a stable cycling over 1000 h for Li|Li symmetric cells, more than 100 cycles in 40-µm-thin Li|high-loading-NCM811 full batteries, and >50 cycles in Cu|LiFePO4 pouch cells, which is a promising electrolyte for highly reversible Li metal batteries.

6.
J Behav Med ; 46(1-2): 303-310, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35133549

RESUMO

Previous studies have shown that self-affirmation increases acceptance of a message and motivates health behavior change. The present study investigated whether self-affirmation increases the acceptance of persuasive messages on COVID-19 vaccines and promotes vaccination intention. A total of 144 participants were randomly assigned to the self-affirmation (n = 72) or control (n = 72) groups before reading a persuasive message on COVID-19 vaccines. The results revealed that the self-affirmation group showed significantly higher acceptance of persuasive information on COVID-19 vaccines than the control group. Additionally, the self-affirmation group also showed significantly higher post-experiment vaccination intention than the control group. Mediation analysis indicated that increased acceptance of persuasive information significantly mediated the beneficial effects of self-affirmation on post-experiment vaccination intention. The present study demonstrated that self-affirmation could be an effective strategy for increasing the acceptance of persuasive messages on COVID-19 vaccines and promoting vaccination intention.


Assuntos
COVID-19 , Intenção , Humanos , Promoção da Saúde/métodos , Vacinas contra COVID-19 , COVID-19/prevenção & controle , Comportamentos Relacionados com a Saúde , Vacinação
7.
ACS Appl Mater Interfaces ; 14(34): 38921-38930, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35980284

RESUMO

The practical application of lithium metal batteries is impeded by the growth of dendrites and decomposition of electrolytes especially at high temperature in normal carbonate-based electrolytes. Herein, a novel urea-based molecule, 1,3-dimethyl-2-imidazolidinone (DMI), with a high donor number is proposed, which exhibits an extraordinary solubility of LiNO3 of over 5 M. As a result, a sufficient amount of LiNO3 is readily introduced into the carbonate electrolytes with DMI as an additive, and an average coulombic efficiency of 99.1% for lithium plating/stripping is achieved due to a stable solid electrolyte interphase (SEI) rich in inorganic-rich lithium salts. The Li||Li symmetric cell achieves a stable operation for over 2500 h at 0.5 mA cm-2 and 1 mAh cm-2, and a granular shape of deposited Li metal is still preserved even at a high current density of 10 mA cm-2. Besides, the decomposition of LiPF6 is inhibited benefiting from its enhanced dissociation after the addition of DMI/LiNO3 and DMI's function as a PF5 scavenger. Consequently, the Li||LiFePO4 cell succeeds to achieve an excellent capacity retention of 95.6% after 2200 cycles at a high rate of 5C, and a stable operation is realized at a high temperature of 60 °C even under harsh conditions (45 µm ultrathin Li and ∼1.5 mAh cm-2 LiFePO4). This work enriches the solvents and additives pool for stable and high-performance lithium metal batteries and will shed light on future developments of advanced battery electrolytes.

8.
Nano Lett ; 22(14): 5936-5943, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35819353

RESUMO

A fluorinated amide molecule with two functional segments, namely, an amide group with a high donor number to bind lithium ions and a fluorine chain to expel carbonate solvents and mediate the formation of LiF, was designed to regulate the interfacial chemistry. As expected, the additive preferably appears in the first solvation sheath of lithium ions and is electrochemically reduced on the anode, and thus an inorganic-rich solid electrolyte interphase is generated. The morphology of deposited lithium metal evolves from brittle dendrites into a granular shape. Consequently, the Li||LiFePO4 cell shows an excellent capacity retention of 92.7% at a high rate of 5 C after 800 cycles. Besides, the Li||LiNi0.8Co0.1Mn0.1O2 cell succeeds to maintain 98.1% of the initial capacity after 100 cycles at 1 C. Our designing of N,N-diethyl- 2,3,3,3-tetrafluoropropionamide (denoted as DETFP) highlights the importance of a "high donor number" and may shed light on the design principles of electrolytes for high performance batteries.

9.
BMC Bioinformatics ; 23(1): 256, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35764916

RESUMO

BACKGROUND: Target drugs play an important role in the clinical treatment of virus diseases. Virus-encoded proteins are widely used as targets for target drugs. However, they cannot cope with the drug resistance caused by a mutated virus and ignore the importance of host proteins for virus replication. Some methods use interactions between viruses and their host proteins to predict potential virus-target host proteins, which are less susceptible to mutated viruses. However, these methods only consider the network topology between the virus and the host proteins, ignoring the influences of protein complexes. Therefore, we introduce protein complexes that are less susceptible to drug resistance of mutated viruses, which helps recognize the unknown virus-target host proteins and reduce the cost of disease treatment. RESULTS: Since protein complexes contain virus-target host proteins, it is reasonable to predict virus-target human proteins from the perspective of the protein complexes. We propose a coverage clustering-core-subsidiary protein complex recognition method named CCA-SE that integrates the known virus-target host proteins, the human protein-protein interaction network, and the known human protein complexes. The proposed method aims to obtain the potential unknown virus-target human host proteins. We list part of the targets after proving our results effectively in enrichment experiments. CONCLUSIONS: Our proposed CCA-SE method consists of two parts: one is CCA, which is to recognize protein complexes, and the other is SE, which is to select seed nodes as the core of protein complexes by using seed expansion. The experimental results validate that CCA-SE achieves efficient recognition of the virus-target host proteins.


Assuntos
Mapas de Interação de Proteínas , Vírus , Análise por Conglomerados , Sistemas de Liberação de Medicamentos , Interações Hospedeiro-Patógeno , Humanos
10.
ACS Appl Mater Interfaces ; 14(21): 24469-24479, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35587195

RESUMO

Poly(ethylene oxide) (PEO)-based solid electrolyte suffers from limited anodic stability and an intrinsic flammable issue, hindering the achievement of high energy density and safe all-solid-state lithium batteries. Herein, we surprisingly found out that a bromine-rich additive, decabromodiphenyl ethane (DBDPE), could be preferably oxidized at an elevated voltage and decompose to lithium bromide at an elevated potential followed by inducing an organic-rich cathode/electrolyte interphase (CEI) on NCM811 surface, enabling both high-voltage resistance (up to 4.5 V) and flame-retardancy for the PEO-based electrolyte. On the basis of this novel solid electrolyte, all-solid-state Li/NCM811 batteries deliver an average reversible capacity of 151.4 mAh g-1 over the first 150 cycles with high capacity retention (83.0%) and high average Coulombic efficiency (99.7%) even at a 4.5 V cutoff voltage with a unprecedented flame-retardant properties. In view of these exploration, our studies revealed the critical role of LiBr in inducing an organic-rich thin and uniform CEI passivating layer with enhanced lithium ion surface diffusion and high-voltage resistant properties, which provides a new protocol for the further design of a high-voltage PEO-based all-solid-state electrolyte.

11.
Nat Commun ; 13(1): 2029, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440573

RESUMO

In electrochemical devices, such as batteries, traditional electric double layer (EDL) theory holds that cations in the cathode/electrolyte interface will be repelled during charging, leaving a large amount of free solvents. This promotes the continuous anodic decomposition of the electrolyte, leading to a limited operation voltage and cycle life of the devices. In this work, we design a new EDL structure with adaptive and passivating properties. It is enabled by adding functional anionic additives in the electrolyte, which can selectively bind with cations and free solvents, forming unique cation-rich and branch-chain like supramolecular polymer structures with high electrochemical stability in the EDL inner layer. Due to this design, the anodic decomposition of ether-based electrolytes is significantly suppressed in the high voltage cathodes and the battery shows outstanding performances such as super-fast charging/discharging and ultra-low temperature applications, which is extremely hard in conventional electrolyte design principle. This unconventional EDL structure breaks the inherent perception of the classical EDL rearrangement mechanism and greatly improve electrochemical performances of the device.

12.
Nat Commun ; 12(1): 732, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531482

RESUMO

The recent advances in accelerated polymerization of N-carboxyanhydrides (NCAs) enriched the toolbox to prepare well-defined polypeptide materials. Herein we report the use of crown ether (CE) to catalyze the polymerization of NCA initiated by conventional primary amine initiators in solvents with low polarity and low hydrogen-bonding ability. The cyclic structure of the CE played a crucial role in the catalysis, with 18-crown-6 enabling the fastest polymerization kinetics. The fast polymerization kinetics outpaced common side reactions, enabling the preparation of well-defined polypeptides using an α-helical macroinitiator. Experimental results as well as the simulation methods suggested that CE changed the binding geometry between NCA and propagating amino chain-end, which promoted the molecular interactions and lowered the activation energy for ring-opening reactions of NCAs. This work not only provides an efficient strategy to prepare well-defined polypeptides with functionalized C-termini, but also guides the design of catalysts for NCA polymerization.

13.
Sci Rep ; 11(1): 3872, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594240

RESUMO

Insertion and Deletion (InDel) are common features in genomes and are associated with genetic variation. The whole-genome re-sequencing data from two parents (X1 and X2) of the elite cucumber (Cucumis sativus) hybrid variety Lvmei No.1 was used for genome-wide InDel polymorphisms analysis. Obtained sequence reads were mapped to the genome reference sequence of Chinese fresh market type inbred line '9930' and gaps conforming to InDel were pinpointed. Further, the level of cross-parents polymorphism among five pairs of cucumber breeding parents and their corresponding hybrid varieties were used for evaluating hybrid seeds purity test efficiency of InDel markers. A panel of 48 cucumber breeding lines was utilized for PCR amplification versatility and phylogenetic analysis of these markers. In total, 10,470 candidate InDel markers were identified for X1 and X2. Among these, 385 markers with more than 30 nucleotide difference were arbitrary chosen. These markers were selected for experimental resolvability through electrophoresis on an Agarose gel. Two hundred and eleven (211) accounting for 54.81% of markers could be validated as single and clear polymorphic pattern while 174 (45.19%) showed unclear or monomorphic genetic bands between X1 and X2. Cross-parents polymorphism evaluation recorded 68 (32.23%) of these markers, which were designated as cross-parents transferable (CPT) InDel markers. Interestingly, the marker InDel114 presented experimental transferability between cucumber and melon. A panel of 48 cucumber breeding lines including parents of Lvmei No. 1 subjected to PCR amplification versatility using CPT InDel markers successfully clustered them into fruit and common cucumber varieties based on phylogenetic analysis. It is worth noting that 16 of these markers were predominately associated to enzymatic activities in cucumber. These agarose-based InDel markers could constitute a valuable resource for hybrid seeds purity testing, germplasm classification and marker-assisted breeding in cucumber.


Assuntos
Cromossomos de Plantas , Cucumis sativus/genética , Marcadores Genéticos , Genoma de Planta , Mutação INDEL , Eletroforese em Gel de Ágar , Filogenia , Especificidade da Espécie , Sequenciamento Completo do Genoma
14.
Front Genet ; 11: 820, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133122

RESUMO

Orphan genes are associated with regulatory patterns, but experimental methods for identifying orphan genes are both time-consuming and expensive. Designing an accurate and robust classification model to detect orphan and non-orphan genes in unbalanced distribution datasets poses a particularly huge challenge. Synthetic minority over-sampling algorithms (SMOTE) are selected in a preliminary step to deal with unbalanced gene datasets. To identify orphan genes in balanced and unbalanced Arabidopsis thaliana gene datasets, SMOTE algorithms were then combined with traditional and advanced ensemble classified algorithms respectively, using Support Vector Machine, Random Forest (RF), AdaBoost (adaptive boosting), GBDT (gradient boosting decision tree), and XGBoost (extreme gradient boosting). After comparing the performance of these ensemble models, SMOTE algorithms with XGBoost achieved an F1 score of 0.94 with the balanced A. thaliana gene datasets, but a lower score with the unbalanced datasets. The proposed ensemble method combines different balanced data algorithms including Borderline SMOTE (BSMOTE), Adaptive Synthetic Sampling (ADSYN), SMOTE-Tomek, and SMOTE-ENN with the XGBoost model separately. The performances of the SMOTE-ENN-XGBoost model, which combined over-sampling and under-sampling algorithms with XGBoost, achieved higher predictive accuracy than the other balanced algorithms with XGBoost models. Thus, SMOTE-ENN-XGBoost provides a theoretical basis for developing evaluation criteria for identifying orphan genes in unbalanced and biological datasets.

15.
ACS Appl Mater Interfaces ; 12(40): 44608-44616, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32921050

RESUMO

Oxygen evolution reaction (OER) with sluggish kinetics is the rate-determining step of water splitting, which dominates the solar-to-hydrogen fuel conversion efficiency. Herein, we constructed an oxygen vacancy-rich and highly reactive (222) facet in Co3O4 nanocrystals anchored on carbon nitride nanofiber (CNF) by a solvothermal reduction method. The resulting Co3O4 nanocrystals/CNF (COCNF) demonstrated a dramatically enhanced OER with a rate of 24.9 µmol/h under visible light, which is 124 times higher than that of CNF. This excellent catalytic activity of COCNF is based on a synergistic effect between its binary components for charge separation, oxygen vacancies for enhanced conductivity, and facet (222) exposure of Co3O4 nanocrystals for improved heterogeneous kinetics. Density functional theory (DFT) calculations revealed the water oxidation mechanism at different facets and found that the formed oxygen vacancies lead to a reduction of the materials' bandgap. The correlation between Co3O4 crystal facets and the inherent OER catalytic activities under acidic solution was in the order of (222) > (220) > (311).

16.
Colloids Surf B Biointerfaces ; 195: 111276, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32763765

RESUMO

Herein, we prepared novel reactive oxygen species (ROS) responsive core crosslinked (CCL/TK) polycarbonate micelles conveniently by click reaction between amphiphilic diblock copolymer poly(ethylene glycol)-poly(5-methyl-5-propargylxycar-bonyl-1,3-dioxane-2-one) (PEG-PMPC) with pendant alkynyl group and thioketal containing azide derivative bis (2-azidoethyl) 3, 3'- (propane-2, 2-diylbis (sulfanediyl)) dipropanoate (TK-N3). The CCL/TK micelles were obtained with small size of 146.4 nm, showing excellent stability against dilution and high doxorubicin (DOX) loading. In vitro toxicity tests demonstrated that the obtained CCL/TK micelles have good biocompatibility and low toxicity with cell viability above 95 %. Furthermore, DOX-loaded CCL/TK micelles showed significantly superior toxicity with IC50 values for HeLa and MCF-7 cells about 3.74 µg/mL and 3.91 µg/mL, respectively. Confocal laser scanning microscope (CLSM) and flow cytometry showed excellent internalization efficiency and intracellular drug release of DOX-loaded CCL/TK micelles. The obtained ROS-responsive CCL/TK micelles showed great potential for anticancer drug delivery.


Assuntos
Doxorrubicina , Micelas , Doxorrubicina/farmacologia , Portadores de Fármacos , Humanos , Cimento de Policarboxilato , Polietilenoglicóis , Polímeros , Espécies Reativas de Oxigênio
17.
Nat Commun ; 10(1): 5470, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784526

RESUMO

Enzymes provide optimal three-dimensional structures for substrate binding and the subsequent accelerated reaction. Such folding-dependent catalytic behaviors, however, are seldom mechanistically explored with reduced structural complexity. Here, we demonstrate that the α-helix, a much simpler structural motif of enzyme, can facilitate its own growth through the self-catalyzed polymerization of N-carboxyanhydride (NCA) in dichloromethane. The reversible binding between the N terminus of α-helical polypeptides and NCAs promotes rate acceleration of the subsequent ring-opening reaction. A two-stage, Michaelis-Menten-type kinetic model is proposed by considering the binding and reaction between the propagating helical chains and the monomers, and is successfully utilized to predict the molecular weights and molecular-weight distributions of the resulting polymers. This work elucidates the mechanism of helix-induced, enzyme-mimetic catalysis, emphasizes the importance of solvent choice in the discovery of new reaction type, and provides a route for rapid production of well-defined synthetic polypeptides by taking advantage of self-accelerated ring-opening polymerizations.


Assuntos
Anidridos/metabolismo , Glutamatos/metabolismo , Polímeros/metabolismo , Conformação Proteica em alfa-Hélice , Aminas/química , Aminas/metabolismo , Anidridos/química , Catálise , Enzimas/química , Enzimas/metabolismo , Glutamatos/química , Cinética , Espectroscopia de Ressonância Magnética , Cloreto de Metileno , Modelos Moleculares , Polimerização , Polímeros/química
18.
Proc Natl Acad Sci U S A ; 116(22): 10658-10663, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31088971

RESUMO

Ribozymes synthesize proteins in a highly regulated local environment to minimize side reactions caused by various competing species. In contrast, it is challenging to prepare synthetic polypeptides from the polymerization of N-carboxyanhydrides (NCAs) in the presence of water and impurities, which induce monomer degradations and chain terminations, respectively. Inspired by natural protein synthesis, we herein report the preparation of well-defined polypeptides in the presence of competing species, by using a water/dichloromethane biphasic system with macroinitiators anchored at the interface. The impurities are extracted into the aqueous phase in situ, and the localized macroinitiators allow for NCA polymerization at a rate which outpaces water-induced side reactions. Our polymerization strategy streamlines the process from amino acids toward high molecular weight polypeptides with low dispersity by circumventing the tedious NCA purification and the demands for air-free conditions, enabling low-cost, large-scale production of polypeptides that has potential to change the paradigm of polypeptide-based biomaterials.


Assuntos
Aminoácidos/química , Anidridos/química , Peptídeos , Polimerização , Cinética , Cloreto de Metileno/química , Modelos Biológicos , Peso Molecular , Biossíntese Peptídica , Peptídeos/síntese química , Peptídeos/química , Água/química
19.
J Mater Chem B ; 6(20): 3348-3357, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32254392

RESUMO

We reported a facile and efficient strategy for the construction of polycarbonate-based core-crosslinked redox-responsive nanoparticles (CC-RRNs), which can efficiently regulate the drug loading content and redox-responsive drug release. A series of CC-RRNs for delivery of doxorubicin (DOX) were synthesized by the click reaction between alkyne-bearing amphiphilic block copolymer PEG-b-poly(MPC)n (PMPC) and azide-terminated α-lipoic acid derivative (LA) and 6-bromohexanoic acid derivative (AHE) at different ratios, followed by introduction of crosslinked networks under a catalytic amount of dithiothreitol (DTT). Dynamic light scattering (DLS) experiments showed that the CC-RRNs presented more excellent stability over non-crosslinked unresponsive nanoparticles (NC-URNs) under physiological conditions. Interestingly, the DOX loading content of nanoparticles (NPs) increased as the proportion of LA moieties increased, and the maximum value was up to 20.0 ± 0.6%, close to the theoretical value of 23.1%. The in vitro redox-responsive release of DOX and MTT assays confirmed that the ratio of LA-to-AHE of PMPC-based polymers not only determined the ultimate drug release of DOX-loaded CC-RRNs in a reductive environment, but also dominated the cytotoxicity towards HepG2 cells. Confocal laser scanning microscopy (CLMS) and flow cytometry further proved the enhancement of cellular uptake and tumor accumulation. This facile strategy overcomes tedious fabrication procedures for drug nanocarriers, offers an opportunity for regulating the functionality of NPs, and thus paves the pathway for scale-up production of biodegradable drug carriers with biocompatibility, stability and targetability.

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