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1.
Nanomicro Lett ; 16(1): 178, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38656466

ABSTRACT

This study presents experimental evidence of the dependence of non-radiative recombination processes on the electron-phonon coupling of perovskite in perovskite solar cells (PSCs). Via A-site cation engineering, a weaker electron-phonon coupling in perovskite has been achieved by introducing the structurally soft cyclohexane methylamine (CMA+) cation, which could serve as a damper to alleviate the mechanical stress caused by lattice oscillations, compared to the rigid phenethyl methylamine (PEA+) analog. It demonstrates a significantly lower non-radiative recombination rate, even though the two types of bulky cations have similar chemical passivation effects on perovskite, which might be explained by the suppressed carrier capture process and improved lattice geometry relaxation. The resulting PSCs achieve an exceptional power conversion efficiency (PCE) of 25.5% with a record-high open-circuit voltage (VOC) of 1.20 V for narrow bandgap perovskite (FAPbI3). The established correlations between electron-phonon coupling and non-radiative decay provide design and screening criteria for more effective passivators for highly efficient PSCs approaching the Shockley-Queisser limit.

2.
Nat Commun ; 15(1): 3001, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589388

ABSTRACT

Designing two-dimensional halide perovskites for high-performance optoelectronic applications requires deep understanding of the structure-property relationship that governs their excitonic behaviors. However, a design framework that considers both intra and interlayer structures modified by the A-site and spacer cations, respectively, has not been developed. Here, we use pressure to synergistically tune the intra and interlayer structures and uncover the structural modulations that result in improved optoelectronic performance. Under applied pressure, (BA)2(GA)Pb2I7 exhibits a 72-fold boost of photoluminescence and 10-fold increase of photoconductivity. Based on the observed structural change, we introduce a structural descriptor χ that describes both the intra and interlayer characteristics and establish a general quantitative relationship between χ and photoluminescence quantum yield: smaller χ correlates with minimized trapped excitons and more efficient emission from free excitons. Building on this principle, we design a perovskite (CMA)2(FA)Pb2I7 that exhibits a small χ and an impressive photoluminescence quantum yield of 59.3%.

3.
Nat Commun ; 15(1): 3164, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38605026

ABSTRACT

Two-dimensional organic-inorganic hybrid halide perovskites possess diverse structural polymorphs with versatile physical properties, which can be controlled by order-disorder transition of the spacer cation, making them attractive for constructing semiconductor homojunctions. Here, we demonstrate a space-cation-dopant-induced phase stabilization approach to creating a lateral homojunction composed of ordered and disordered phases within a two-dimensional perovskite. By doping a small quantity of pentylammonium into (butylammonium)2PbI4 or vice versa, we effectively suppress the ordering transition of the spacer cation and the associated out-of-plane octahedral tilting in the inorganic framework, resulting in phase pining of the disordered phase when decreasing temperature or increasing pressure. This enables epitaxial growth of a two-dimensional perovskite homojunction with tunable optical properties under temperature and pressure stimuli, as well as directional exciton diffusion across the interface. Our results demonstrate a previously unexplored strategy for constructing two-dimensional perovskite heterostructures by thermodynamic tuning and spacer cation doping.

4.
Foods ; 12(22)2023 Nov 13.
Article in English | MEDLINE | ID: mdl-38002173

ABSTRACT

Because of the health benefits and economic opportunities, extracting bioactive peptides from plant proteins, often food processing by-products, garners significant interest. However, the high enzyme costs and the emergence of bitter peptides have posed significant challenges in production. This study achieved the immobilization of Alcalase and Flavorzyme using cost-effective SiO2 microparticles. Mussel-inspired chemistry and biocompatible polymers were employed, with genipin replacing glutaraldehyde for safer crosslinking. This approach yielded an enzyme loading capacity of approximately 25 mg/g support, with specific activity levels reaching around 180 U/mg for immobilized Alcalase (IA) and 35 U/mg for immobilized Flavorzyme (IF). These immobilized proteases exhibited improved activity and stability across a broader pH and temperature range. During the hydrolysis of soy proteins, the use of immobilized proteases avoided the thermal inactivation step, resulting in fewer peptide aggregates. Moreover, this study applied peptidomics and bioinformatics to profile peptides in each hydrolysate and identify bioactive ones. Cascade hydrolysis with IA and IF reduced the presence of bitter peptides by approximately 20%. Additionally, 50% of the identified peptides were predicted to have bioactive properties after in silico digestion simulation. This work offers a cost-effective way of generating bioactive peptides from soy proteins with reducing potential bitterness.

5.
J Am Chem Soc ; 145(43): 23842-23848, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37859342

ABSTRACT

Organic-inorganic halide perovskites possess unique electronic configurations and high structural tunability, rendering them promising for photovoltaic and optoelectronic applications. Despite significant progress in optimizing the structural characteristics of the organic cations and inorganic framework, the role of organic-inorganic interactions in determining the structural and optical properties has long been underappreciated and remains unclear. Here, by employing pressure tuning, we realize continuous regulation of organic-inorganic interactions in a lead halide perovskite, MHyPbBr3 (MHy+ = methylhydrazinium, CH3NH2NH2+). Compression enhances the organic-inorganic interactions by strengthening the Pb-N coordinate bonding and N-H···Br hydrogen bonding, which results in a higher structural distortion in the inorganic framework. Consequently, the second-harmonic-generation (SHG) intensity experiences an 18-fold increase at 1.5 GPa, and the order-disorder phase transition temperature of MHyPbBr3 increases from 408 K under ambient pressure to 454 K at the industrially achievable level of 0.5 GPa. Further compression triggers a sudden non-centrosymmetric to centrosymmetric phase transition, accompanied by an anomalous bandgap increase by 0.44 eV, which stands as the largest boost in all known halide perovskites. Our findings shed light on the intricate correlations among organic-inorganic interactions, octahedral distortion, and SHG properties and, more broadly, provide valuable insights into structural design and property optimization through cation engineering of halide perovskites.

6.
J Agric Food Chem ; 71(14): 5686-5699, 2023 Apr 12.
Article in English | MEDLINE | ID: mdl-37012896

ABSTRACT

This study sought to understand how the features of proteins impact the properties of nanoparticles assembled using the pH-shifting approach and the mechanism behind. Four legume protein isolates from faba bean, mung bean, soy, and pea were fractionated into natural aqueous-soluble (Sup) and aqueous-insoluble (Sed) fractions, which were proved to serve as shell and core, respectively, for the pH-driven-assembled nanoparticles. Using zein instead of Sed fractions as the core improved size uniformity, and particle size can be precisely controlled by adjusting core/shell ratios. Using the proteomic technique and silico characterization, the features of identified proteins indicated that hydrophobicity rather than molecular weight, surface charge, etc., mainly determined particle size. With molecular docking, structural analysis, and dissociation tests, the assembly of zein/Sup-based nanoparticles was dominantly driven by hydrophobic interactions. This study provides constructive information on the correlation between protein features and the properties of pH-driven-assembled nanoparticles, achieving a precise control of particle size.


Subject(s)
Nanoparticles , Zein , Particle Size , Zein/chemistry , Molecular Docking Simulation , Proteomics , Proteins/chemistry , Nanoparticles/chemistry , Hydrogen-Ion Concentration
7.
Sci Adv ; 8(44): eadd1984, 2022 Nov 04.
Article in English | MEDLINE | ID: mdl-36322656

ABSTRACT

Two-dimensional (2D) semiconductor heterostructures are key building blocks for many electronic and optoelectronic devices. Reconfiguring the band-edge states and modulating their interplay with charge carriers at the interface in a continuous manner have long been sought yet are challenging. Here, using organic semiconductor-incorporated 2D halide perovskites as the model system, we realize the manipulation of band-edge states and charge distribution via mechanical-rather than chemical or thermal-regulation. Compression induces band-alignment switching and charge redistribution due to the different pressure responses of organic and inorganic building blocks, giving controllable emission properties of 2D perovskites. We propose and demonstrate a "pressure gating" strategy that enables the control of multiple emission states within a single material. We also reveal that band-alignment transition at the organic-inorganic interface is intrinsically not well resolved at room temperature owing to the thermally activated transfer and shuffling of band-edge carriers. This work provides important fundamental insights into the energetics and carrier dynamics of hybrid semiconductor heterostructures.

8.
Article in English | MEDLINE | ID: mdl-35990851

ABSTRACT

Objective: To evaluate the efficacy of fluticasone and salmeterol dry powder in treating patients with bronchial asthma and its effects on inflammatory factors and pulmonary function. Methods: One hundred patients with bronchial asthma, admitted to our hospital between April 2019 and June 2020, were enrolled and assigned into two groups using the random number table method. The observation group (n = 50) received budesonide powder, and the experimental group received fluticasone and salmeterol dry powder. The two groups were compared with regard to clinical efficacy, inflammatory factors, pulmonary function, and adverse reactions. Results: In the experimental group, the total effective rate of treatment was significantly higher than that in the observation group (P < 0.05); after treatment, the levels of inflammatory factors in the experimental group were lower than those in the observation group (P < 0.05); after treatment, lung function in the experimental group was significantly higher than that in the observation group (P < 0.05); the incidence of adverse reactions in the experimental group was significantly lower than that in the observation group (P < 0.05). Conclusion: Salmeterol and fluticasone powder has shown impressive clinical benefits in the treatment of bronchial asthma patients. It might be a viable approach to reduce inflammatory factors and improve pulmonary function. Moreover, its good clinical safety profile makes it a promising treatment that ought to be promoted and used widely.

9.
Int J Mol Sci ; 23(6)2022 Mar 08.
Article in English | MEDLINE | ID: mdl-35328337

ABSTRACT

This study aimed to improve the stability and catalytic properties of Thermomyces lanuginosus lipase (TLL) adsorbed on a hydrophobic support. At the optimized conditions (pH 5 and 25 °C without any additions), the Sips isotherm model effectively fitted the equilibrium adsorption data, indicating a monolayer and the homogenous distribution of immobilized lipase molecules. To preserve the high specific activity of adsorbed lipase, the immobilized lipase (IL) with a moderate loading amount (approximately 40% surface coverage) was selected. Polyethylenimine (PEI) and chitosan (CS) were successfully applied as bridging units to in situ crosslink the immobilized lipase molecules in IL. At the low polymer concentration (0.5%, w/w) and with 1 h incubation, insignificant changes in average pore size were detected. Short-chain PEI and CS (MW ≤ 2 kDa) efficiently improved the lipase stability, i.e., the lipase loss decreased from 40% to <2%. Notably, CS performed much better than PEI in maintaining lipase activity. IL crosslinked with CS-2 kDa showed a two- to three-fold higher rate when hydrolyzing p-nitrophenyl butyrate and a two-fold increase in the catalytic efficiency in the esterification of hexanoic acid with butanol. These in situ crosslinking strategies offer good potential for modulating the catalytic properties of TLL for a specific reaction.


Subject(s)
Chitosan , Eurotiales , Enzymes, Immobilized/chemistry , Lipase/chemistry , Polyethyleneimine/chemistry , Polymers
10.
Am J Transl Res ; 13(11): 13209-13215, 2021.
Article in English | MEDLINE | ID: mdl-34956542

ABSTRACT

OBJECTIVE: This research was aimed to evaluate the impact of high-quality nursing (HQN) plus respiratory training on treatment compliance, pulmonary function (PF) and quality of life (QoL) of patients with chronic obstructive pulmonary disease (COPD). METHODS: We retrospectively analyzed 89 COPD patients who were treated at the affiliated Nanhua Hospital from February 2019 to February 2021. Among them, 40 cases received drug treatment and breathing training as the control group, and 49 cases were supplemented with HQN as the experimental group on the basis of the control group. The changes in PF, quality of life and compliance were compared between the two groups. RESULTS: Vital capacity (VC) and alveolar ventilation (VA) increased in both cohorts after treatment (P < 0.05), and increased more significantly in experimental group compared with control group (P < 0.05). Experimental group also presented markedly higher total effective rate and noticeably lower scores of symptoms, activities and disease impact on daily life than control group (P < 0.05). CONCLUSIONS: HQN plus respiratory training can effectively improve the PF, efficacy and QoL of patients with COPD.

11.
Electrophoresis ; 42(24): 2599-2614, 2021 12.
Article in English | MEDLINE | ID: mdl-33314167

ABSTRACT

The application of monolithic materials as carriers for enzymes has rapidly expanded to the realization of flow-through analysis and bioconversion processes. This expansion is partly attributed to the absence from diffusion limitation in many monoliths-based enzyme reactors. Particularly, the relatively ease of introducing functional groups renders polymer monoliths attractive as enzyme carriers. After summarizing the motivation to develop enzymatic reactors using polymer monoliths, this review reports the most recent applications of such reactors. Besides, the present review focuses on the crucial characteristics of polymer monoliths affecting the immobilization of enzymes and the processing parameters dictating the performance of the resulting enzymatic reactors. This review is intended to provide a guideline for designing and applying flow-through enzymatic reactors using polymer monoliths.


Subject(s)
Bioreactors , Enzymes, Immobilized , Polymers , Motivation
12.
Transl Cancer Res ; 9(2): 726-734, 2020 Feb.
Article in English | MEDLINE | ID: mdl-35117418

ABSTRACT

BACKGROUND: This study aimed to evaluate the correlation of A-kinase-interacting protein 1 (AKIP1) with C-X-C motif chemokine ligand (CXCL) 1 and CXCL2, and their associations with clinical characteristics and prognosis in cervical cancer patients. METHODS: One hundred and fifty early-stage cervical cancer patients treated with surgical resection were reviewed and tumor tissue samples were obtained. Expression of AKIP1, CXCL1 and CXCL2 was detected by immunohistochemistry (IHC). Data of tumor features were retrieved, and disease-free survival (DFS) as well as overall survival (OS) were calculated. RESULTS: AKIP1 expression was positively correlated with CXCL1 and CXCL2 expression in cervical cancer tissue (both P<0.001). AKIP1 expression was positively correlated with tumor size (P=0.040), lymph node (LYN) metastasis (P=0.034) and International Federation of Gynecology and Obstetrics (FIGO) stage (P=0.021); CXCL1 expression was positively associated with tumor size (P=0.048); and CXCL2 expression was positively correlated with LYN metastasis (P=0.026). As for DFS and OS, AKIP1 high expression was correlated with worse DFS (P=0.016) and OS (P=0.007), CXCL1 high expression was associated with poor DFS (P=0.029) but not OS (P=0.118). No correlation of CXCL2 expression with DFS (P=0.141) or OS (P=0.125) was found. CONCLUSIONS: AKIP1 positively correlates with CXCL1/CXCL2, and associates with advanced tumor features as well as unfavorable survival profiles in cervical cancer patients.

13.
Food Chem ; 253: 194-202, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29502821

ABSTRACT

Although immobilized trypsin is a viable alternative to the free one in solution for producing protein hydrolysates, the change of selectivity introduced by immobilization is unclear. In this study, we compared the selectivity of free and immobilized trypsin towards different cleavage sites of ß-lactoglobulin (ß-Lg) with a focus on the impact of environmental pH. Both free and immobilized trypsin exhibited greater accessibility to native ß-Lg at elevated pH (from pH 7.2 to 8.7). Additionally, free trypsin preferred to attack cleavage sites located at the C-terminus at pH 7.8, whereas an opposite preference for the N-terminus was observed at pH 8.7. Regarding the immobilized trypsin, the pH did not significantly influence its preference for the C- or N-terminus. Generally, immobilization of trypsin resulted in more focused cleavage within its specificity during the initial stage of hydrolysis, and some peptides were formed more rapidly by the immobilized trypsin.


Subject(s)
Enzymes, Immobilized/metabolism , Lactoglobulins/metabolism , Trypsin/metabolism , Hydrogen-Ion Concentration , Hydrolysis , Peptides/metabolism , Substrate Specificity
14.
Electrophoresis ; 38(22-23): 2947-2956, 2017 11.
Article in English | MEDLINE | ID: mdl-28714138

ABSTRACT

Tryptic hydrolysis of ß-Lactoglobulin (ß-Lg) is attracting more and more attention due to the reduced allergenicity and the functionality of resulting hydrolysates. To produce hydrolysates in an economically viable way, immobilized trypsin reactors (IMTRs), based on polymethacrylate monolith with pore size 2.1 µm (N1) and 6 µm (N2), were developed and used in a flow-through system. IMTRs were characterized in terms of permeability and enzymatic activity during extensive usage. N1 showed twice the activity compared with N2, correlating well with its almost two times higher amount of immobilized trypsin. N2 showed high stability over 18 cycles, as well as over more than 30 weeks during storage. The efficiency of IMTRs on hydrolyzing ß-Lg was compared with free trypsin, and the resulting hydrolysates were analyzed by MALDI-TOF/MS. The final hydrolysis degree by N1 reached 9.68% (86.58% cleavage sites) within 4 h, while only around 6% (53.67% cleavage sites) by 1.5 mg of free trypsin. Peptides analysis showed the different preference between immobilized trypsin and free trypsin. Under the experimental conditions used in this study, the potential cleavage site Lys135 -Phe136 was resistant against the immobilized trypsin in N1.


Subject(s)
Bioreactors , Enzymes, Immobilized/metabolism , Lactoglobulins/metabolism , Trypsin/metabolism , Chromatography , Enzyme Stability , Enzymes, Immobilized/chemistry , Hydrolysis , Lactoglobulins/analysis , Lactoglobulins/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Trypsin/chemistry
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