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1.
Anal Biochem ; 696: 115692, 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39427855

RESUMEN

Bispecific antibodies, a class of therapeutic antibodies, can simultaneously bind to two distinct targets. Compared with monospecific antibodies, bispecific antibodies offer advantages, including superior efficacy and reduced side effects. However, because of their structural complexity, the purification of bispecific antibodies is highly challenging. The purification process must strike a delicate balance between purity and productivity, eliminating a broad spectrum of contaminants, including product-related and process-related impurities, while also maximizing the yield wherever feasible. This review systematically describes the strategies for bispecific antibody capture, the elimination of product-related impurities, and the mitigation of the formation of process-related impurities, thereby, providing guidance for the development of downstream purification processes for bispecific antibodies.

2.
Photochem Photobiol Sci ; 23(6): 1051-1065, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38684635

RESUMEN

As a member of the SMAD family, SMAD4 plays a crucial role in several cellular biological processes. However, its function in UVB radiation-induced keratinocyte damage is not yet clarified. Our study aims to provide mechanistic insight for the development of future UVB protective therapies and therapeutics involving SMAD4. HaCaT cells were treated with UVB, and the dose dependence and time dependence of UVB were measured. The cell function of UVB-treated HaCaT cells and the activity of epithelial-mesenchymal transition (EMT) after overexpression or silencing of SMAD4 was observed by flow cytometry, quantitative reverse transcription PCR (qRT-PCR) and Western Blots (WB). We found that a significant decrease in SMAD4 was observed in HaCaT cells induced by UVB. Our data confirm SMAD4 as a direct downstream target of miR-664. The down-regulation of SMAD4 preserved the viability of the UVB-treated HaCaT cells by inhibiting autophagy or apoptosis. Furthermore, the silencing of SMAD4 activated the EMT process in UVB-treated HaCaT cells. Down-regulation of SMAD4 plays a protective role in UVB-treated HaCaT cells via the activation of EMT.


Asunto(s)
Transición Epitelial-Mesenquimal , Proteína Smad4 , Humanos , Apoptosis/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Regulación hacia Abajo , Transición Epitelial-Mesenquimal/efectos de la radiación , Células HaCaT , Queratinocitos/metabolismo , Queratinocitos/efectos de la radiación , Queratinocitos/citología , Estrés Oxidativo/efectos de la radiación , Proteína Smad4/metabolismo , Rayos Ultravioleta
3.
Nanotechnology ; 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39389088

RESUMEN

Metal halide scintillators serve as a compelling substitute for traditional scintillators in X-ray detection and imaging due to their low-temperature fabrication process, high light yield and mechanical flexibility. Nevertheless, the spatial resolution and photoluminescence quantum yield (PLQY) of these films are hindered by the agglomeration and uneven distribution of metal halides crystal particles during the fabrication process. We introduce a modified fabrication approach for metal halide scintillator films involving an additional step of ethyl acetate (EA) treatment, resulting in the preparation of a smooth EA-treated (Ph4P)2MnBr4/Polydimethylsiloxane film. The carbonyl groups within EA interact with elements of the (Ph4P)2MnBr4 microcrystals powder, ensuring uniform dispersion and preventing agglomeration. The EA-treated composite film demonstrates a remarkable PLQY of approximately 95% and an impressive spatial resolution of 14 lp/mm, with enhanced stability under harsh environments. These characteristics ensure its suitability as a high-performance X-ray imaging scintillator. .

4.
J Foot Ankle Surg ; 63(6): 668-671, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38972566

RESUMEN

It has been demonstrated in a number of studies that high levels of uric acid can cause crystal deposition in the tendons of the lower extremities, which in turn can impair the Achilles tendon. This study aimed to interpret whether hyperuricemia is relevant with Achilles tendon rupture. Patients diagnosed with Achilles tendon rupture at the same institution between 2013 and 2022 were included in the case group. Healthy subjects who had physical examinations during the same period were included in the control group. Propensity score matching was used to match in a 1:1 ratio. Demographic and clinical characteristics of patients in both groups were compared. Five hundred and fourteen patients were included in the study (ATR=257; Control group=257). The proportion of individuals with hyperuricemia varied significantly between the 2 groups (Achilles tendon rupture group=43.6%; control group=27.6%; p<0.001). The Achilles tendon rupture and hyperuricemia were linked by conditional logistic regression (p<0.001; OR=2.036; 95CI%=1.400-2.961). Compared with healthy subjects, patients with hyperuricemia have a higher risk of Achilles tendon rupture. Further studies are required to verify the effects of hyperuricemia and monosodium urate crystals on Achilles tendon structure.


Asunto(s)
Tendón Calcáneo , Hiperuricemia , Traumatismos de los Tendones , Humanos , Tendón Calcáneo/lesiones , Hiperuricemia/complicaciones , Femenino , Masculino , Estudios de Casos y Controles , Persona de Mediana Edad , Rotura , Adulto , Factores de Riesgo , Puntaje de Propensión , Estudios Retrospectivos , Anciano
5.
Nanotechnology ; 34(24)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36881878

RESUMEN

Metal halide perovskite quantum dots (QDs) have excellent optoelectronic properties; however, their poor stability under water or thermal conditions remains an obstacle to commercialization. Here, we used a carboxyl functional group (-COOH) to enhance the ability of a covalent organic framework (COF) to adsorb lead ions and grow CH3NH3PbBr3(MAPbBr3) QDsin situinto a mesoporous carboxyl-functionalized COF to construct MAPbBr3QDs@COF core-shell-like composites to improve the stability of perovskites. Owing to the protection of the COF, the as-prepared composites exhibited enhanced water stability, and the characteristic fluorescence was maintained for more than 15 d. These MAPbBr3QDs@COF composites can be used to fabricate white light-emitting diodes with a color comparable to natural white emission. This work demonstrates the importance of functional groups for thein situgrowth of perovskite QDs, and coating with a porous structure is an effective way to improve the stability of metal halide perovskites.

6.
Angew Chem Int Ed Engl ; 60(5): 2485-2492, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33079422

RESUMEN

Surface passivation of perovskite solar cells (PSCs) using a low-cost industrial organic pigment quinacridone (QA) is presented. The procedure involves solution processing a soluble derivative of QA, N,N-bis(tert-butyloxycarbonyl)-quinacridone (TBOC-QA), followed by thermal annealing to convert TBOC-QA into insoluble QA. With halide perovskite thin films coated by QA, PSCs based on methylammonium lead iodide (MAPbI3 ) showed significantly improved performance with remarkable stability. A PCE of 21.1 % was achieved, which is much higher than 18.9 % recorded for the unmodified devices. The QA coating with exceptional insolubility and hydrophobicity also led to greatly enhanced contact angle from 35.6° for the pristine MAPbI3 thin films to 77.2° for QA coated MAPbI3 thin films. The stability of QA passivated MAPbI3 perovskite thin films and PSCs were significantly enhanced, retaining about 90 % of the initial efficiencies after more than 1000 hours storage under ambient conditions.

7.
Angew Chem Int Ed Engl ; 59(51): 23067-23071, 2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-32876977

RESUMEN

The photophysical tuning is reported for a series of tetraphenylphosphonium (TPP) metal halide hybrids containing distinct metal halides, TPP2 MXn (MXn =SbCl5 , MnCl4 , ZnCl4 , ZnCl2 Br2 , ZnBr4 ), from efficient phosphorescence to ultralong afterglow. The afterglow properties of TPP+ cations could be suspended for the hybrids containing low band gap emissive metal halide species, such as SbCl5 2- and MnCl4 2- , but significantly enhanced for the hybrids containing wide band gap non-emissive ZnCl4 2- . Structural and photophysical studies reveal that the enhanced afterglow is attributed to stronger π-π stacking and intermolecular electronic coupling between TPP+ cations in TPP2 ZnCl4 than in the pristine organic ionic compound TPPCl. Moreover, the afterglow in TPP2 ZnX4 can be tuned by controlling the halide composition, with the change from Cl to Br resulting in a shorter afterglow due to the heavy atom effect.

8.
Chemistry ; 21(10): 4085-91, 2015 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-25640264

RESUMEN

Two-dimensional (2D) semiconducting nanosheets have emerged as an important field of materials, owing to their unique properties and potential applications in areas ranging from electronics to catalysis. However, the controlled synthesis of ultrathin 2D nanosheets remains a great challenge, due to the lack of an intrinsic driving force for anisotropic growth. High-quality ultrathin 2D FeSe2 nanosheets with average thickness below 7 nm have been synthesized on large scale by a facile solution method, and a formation mechanism has been proposed. Due to their favorable structural features, the as-synthesized ultrathin FeSe2 nanosheets exhibit excellent electrocatalytic activity for the reduction of triiodide to iodide and low charge-transfer resistance at the electrolyte-electrode interface in dye-sensitized solar cells (DSSCs). The DSSCs with FeSe2 nanosheets as counter electrode material achieve a high power conversion efficiency of 7.53% under a simulated solar illumination of 100 mW cm(-2) (AM 1.5), which is comparable with that of Pt-based devices (7.47%).

9.
Chemistry ; 21(43): 15153-7, 2015 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-26338374

RESUMEN

It is generally believed that silver or silver-based compounds are not suitable counter electrode (CE) materials for dye-sensitized solar cells (DSSCs) due to the corrosion of the I(-) /I3 (-) redox couple in electrolytes. However, Ag2 S has potential applications in DSSCs for catalyzing I3 (-) reduction reactions because of its high carrier concentration and tiny solubility product constant. In the present work, CE manufactured from Ag2 S nanocrystals ink exhibited efficient electrocatalytic activity in the reduction of I3 (-) to I(-) in DSSCs. The DSSC consisting of Ag2 S CE displayed a higher power conversion efficiency of 8.40 % than that of Pt CE (8.11 %). Moreover, the devices also showed the characteristics of fast activity onset, high multiple start/stop capability and good irradiated stability. The simple composition, easy preparation, stable chemical property, and good catalytic performance make the developed Ag2 S CE as a promising alternative to Pt CE in DSSCs.

10.
Nanomaterials (Basel) ; 13(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36770381

RESUMEN

Metal halide perovskites are promising energy materials because of their high absorption coefficients, long carrier lifetimes, strong photoluminescence, and low cost. Low-dimensional halide perovskites, especially one-dimensional (1D) halide perovskite nanowires (NWs), have become a hot research topic in optoelectronics owing to their excellent optoelectronic properties. Herein, we review the synthetic strategies and mechanisms of halide perovskite NWs in recent years, such as hot injection, vapor phase growth, selfassembly, and solvothermal synthesis. Furthermore, we summarize their applications in optoelectronics, including lasers, photodetectors, and solar cells. Finally, we propose possible perspectives for the development of halide perovskite NWs.

11.
ACS Appl Mater Interfaces ; 15(35): 41906-41915, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37610108

RESUMEN

With the rapid development of electronic information technology, composite materials with outstanding performance in terms of electromagnetic interference (EMI) shielding and strain sensing are crucial for next-generation smart wearable electronic devices. However, the fabrication of flexible composite films with dual functionality remains a significant challenge. Herein, multifunctional flexible composite films with exciting EMI shielding and strain sensing properties were constructed using a facile vacuum-assisted filtration process and transfer method. The films consisted of ultrathin AgNW/MXene (Ti3C2Tx)/AgNW conductive networks (1 µm) attached to a flexible polydimethylsiloxane (PDMS) substrate. The obtained AgNW/MXene/PDMS composite film exhibited an exceptional EMI shielding effectiveness of 50.82 dB and good flexibility (retaining 93.67 and 90.18% of its original value after 1000 bending and stretching cycles, respectively), which are attributed to the enhanced multilayer internal reflection network created by the AgNWs and MXene as well as the synergistic effect of PDMS. Besides EMI shielding, the composite films also displayed remarkable strain sensing properties. They exhibited a wide linear range of tensile strain up to 68% with a gauge factor of 468. They also showed fast response, ultralow detection limit, and high mechanical stability. Interestingly, the composite films could also detect motion and voice recognition, demonstrating their potential as wearable sensors. This study highlights the effectiveness of multifunctional flexible AgNW/MXene/PDMS composite films in resisting electromagnetic radiation and monitoring human motion, thereby providing a promising solution for the development of flexible wearable electronic devices in complex electromagnetic environments.

12.
Artículo en Inglés | MEDLINE | ID: mdl-37270861

RESUMEN

Small amounts of by-products are nevertheless created during the recombinant production of IgG-like bispecific antibodies due to imbalanced chain expression and improper chain pairing, despite the employment of molecular strategy techniques to promote accurate pairing. Among them, homodimers represent the species that are more difficult to remove due to their physical and chemical properties being similar to the target antibody. Homodimer by-products are always produced even though various technologies can significantly increase the expression of heterodimers, so a robust purification process to recover high-purity heterodimers is required. Most of the chromatography methods commonly adopt the bind-and-elute mode or two-step to separate homodimers, which has numerous drawbacks such as prolonged process times and limited dynamic binding capacity. Flow-through mode of anion exchange is a frequently-used polishing step for antibodies, but it is typically regarded as being more effective for host-cell protein or host-cell DNA removal rather than other product-related impurities such as homodimers and aggregates. This paper demonstrated that single-step anion exchange chromatography allows high capacity and effective clearance of the homodimer byproduct to be simultaneously achieved, suggesting that weak partitioning was a better polishing strategy for achieving a high level of heterodimer purity. And robust operation range of anion exchange chromatography steps for homodimer removal was also developed by leveraging the design of experiments.


Asunto(s)
Anticuerpos Biespecíficos , Anticuerpos Biespecíficos/análisis , Cromatografía , Proteínas , Aniones , Cromatografía por Intercambio Iónico/métodos
13.
Nat Commun ; 11(1): 4329, 2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32859920

RESUMEN

Scintillation based X-ray detection has received great attention for its application in a wide range of areas from security to healthcare. Here, we report highly efficient X-ray scintillators with state-of-the-art performance based on an organic metal halide, ethylenebis-triphenylphosphonium manganese (II) bromide ((C38H34P2)MnBr4), which can be prepared using a facile solution growth method at room temperature to form inch sized single crystals. This zero-dimensional organic metal halide hybrid exhibits green emission peaked at 517 nm with a photoluminescence quantum efficiency of ~ 95%. Its X-ray scintillation properties are characterized with an excellent linear response to X-ray dose rate, a high light yield of ~ 80,000 photon MeV-1, and a low detection limit of 72.8 nGy s-1. X-ray imaging tests show that scintillators based on (C38H34P2)MnBr4 powders provide an excellent visualization tool for X-ray radiography, and high resolution flexible scintillators can be fabricated by blending (C38H34P2)MnBr4 powders with polydimethylsiloxane.

14.
ACS Appl Mater Interfaces ; 12(1): 1159-1168, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31825589

RESUMEN

The interfaces between perovskite and charge transport layers greatly impact the device efficiency and stability of perovskite solar cells (PSCs). Inserting an ultrathin wide-band-gap layer between perovskite and hole transport layers (HTLs) has recently been shown as an effective strategy to enhance device performance. Herein, a small amount of an organic halide salt, N,N'-dimethylethylene-1,2-diammonium iodide, is used to create two-dimensional (2D)-three-dimensional (3D) heterojunctions on MAPbI3 thin film surfaces by facile solution processing. The formation of an ultrathin wide-band-gap 2D perovskite layer on top of 3D MAPbI3 changes the morphological and photophysical properties of perovskite thin films, effectively reduces the surface defects, and suppresses the charge recombination in the interfaces between perovskite and HTL. As a result, a power conversion efficiency of ∼20.2%, with an open-circuit voltage of 1.14 V, a short-circuit current density of 22.57 mA cm-2, and a fill factor of 0.78, is achieved for PSCs with enhanced stability.

15.
ACS Appl Mater Interfaces ; 12(40): 45056-45063, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32909428

RESUMEN

The fabrication of efficient and spectrally stable pure-blue perovskite light-emitting diodes (LEDs) has been elusive and remains of great interest. Herein, we incorporate diammonium salts into quasi-2D perovskite precursors for phase control of multiple quantum well structures to yield tunable and efficient emission in the blue region. With detailed characterizations and computational studies, we show that in situ passivation by the diammonium salts effectively modifies the surface energies of quasi-2D phases and inhibits the growth of low-band gap quasi-2D and 3D phases. Such phase control and in situ passivation could afford blue light-emitting perovskite thin films with high photoluminescence quantum efficiencies of, for instance, 75% for the emission peak at 471 nm. Using this perovskite thin film as an emitting layer, spectrally stable pure-blue LEDs with an emission peak at 474 nm and a full width at half-maximum of 26 nm could be fabricated to exhibit a brightness of 290 cd m-2 at 8 V and an external quantum efficiency of 2.17%.

16.
ACS Appl Mater Interfaces ; 12(34): 38003-38011, 2020 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-32799530

RESUMEN

Metal ion-linked multilayers offer an easily prepared and modular architecture for controlling energy and electron transfer events on nanoparticle, metal oxide films. However, unlike with planar electrodes, the mesoporous nature of the films inherently limits both the thickness of the multilayer and subsequent diffusion through the pores. Here, we systematically investigated the role of TiO2 nanoparticle film porosity and metal ion-linked multilayer thickness in surface loading, through-pore diffusion, and overall device performance. The TiO2 porosity was controlled by varying TiO2 sintering times. Molecular multilayer thickness was controlled through assembling ZnII-linked bridging molecules (B = p-terphenyl diphosphonic acid) between the metal oxide and the Ru(bpy)2((4,4'-PO3H2)2bpy)]Cl2 dye (RuP), thus producing TiO2-(Bn)-RuP films. Using attenuated total reflectance infrared absorption and UV-vis spectroscopy, we observed that at least two molecular layers (i.e., TiO2-B2 or TiO2-B1-RuP) could be formed on all films but subsequent loading was dependent on the porosity of the TiO2. Rough estimates indicate that in a film with 34 nm average pore diameter, the maximum multilayer film thickness is on the order of 4.6-6 nm, which decreases with decreasing pore size. These films were then incorporated as the photoanodes in dye-sensitized solar cells with cobalt(II/III)tris(4,4'-di-tert-butyl-2,2'-bipyridine) as a redox mediator. In agreement with the surface-loading studies, electrochemical impedance spectroscopy measurements indicate that mediator diffusion is significantly hindered in films with thicker multilayers and less porous TiO2. Collectively, these results show that care must be taken to balance multilayer thickness, substrate porosity, and size of the mediator in designing and maximizing the performance of new multilayer energy and electron management architectures.

17.
Sci Adv ; 6(17): eaaz5961, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32426465

RESUMEN

Metal halide perovskite nanocrystals (NCs) have emerged as new-generation light-emitting materials with narrow emissions and high photoluminescence quantum efficiencies (PLQEs). Various types of perovskite NCs, e.g., platelets, wires, and cubes, have been discovered to exhibit tunable emissions across the whole visible spectrum. Despite remarkable advances in the field of perovskite NCs, many nanostructures in inorganic NCs have not yet been realized in metal halide perovskites, and producing highly efficient blue-emitting perovskite NCs remains challenging and of great interest. Here, we report the discovery of highly efficient blue-emitting cesium lead bromide (CsPbBr3) perovskite hollow NCs. By facile solution processing of CsPbBr3 precursor solution containing ethylenediammonium bromide and sodium bromide, in situ formation of hollow CsPbBr3 NCs with controlled particle and pore sizes is realized. Synthetic control of hollow nanostructures with quantum confinement effect results in color tuning of CsPbBr3 NCs from green to blue, with high PLQEs of up to 81%.

18.
J Phys Chem Lett ; 10(19): 5836-5840, 2019 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-31525868

RESUMEN

The rich chemistry of metal halide perovskites has enabled various methods of band structure control and surface passivation. Here we report a highly facile and efficient post-treatment approach for precise color tuning of cesium lead halide perovskite nanocrystals (NCs) with enhanced stability. By utilizing a special multifunctional organic ligand, triphenyl(9-phenyl-9H-carbazol-3-yl)phosphonium bromide (TPP-Carz), carbon-halide bond cleavage can be achieved to release halide ions from halogenated solvents in a controlled manner for color tuning of perovskite NCs via ion exchange. Besides controlled release of halide ions for anion exchange, TPP-Carz can effectively passivate the surfaces of perovskite NCs simultaneously. As a result, perovskite NCs prepared by this post-treatment method with tunable colors over the entire visible spectrum have shown significantly improved luminescence and stability in comparison to the ones prepared using reactive anion precursors without surface passivation by TPP-Carz.

19.
J Phys Chem Lett ; 10(19): 5923-5928, 2019 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-31529944

RESUMEN

Organometal halide perovskite materials, in particular colloidal perovskite nanocrystals (NCs), have been investigated extensively as next-generation light-emitting materials. However, producing highly efficient and stable perovskite thin films from colloidal NCs is not trivial, as dissociation of surfactants often occurs during the thin-film formation. Here, we demonstrate a facile solution-processing approach to prepare perovskite nanocomposite thin films by using phosphonium as the capping ligand for methylammonium lead bromide (MAPbBr3) NCs. The photoluminescence and stability of thin films containing in situ formed perovskite NCs were greatly enhanced after phosphonium passivation, with the photoluminescence quantum efficiency reaching 78% and only 5% decrease of the intensity after one month's exposure in ambient conditions. Electrically driven light-emitting diodes (LEDs) based on pristine perovskite neat thin films and organic-perovskite nanocomposite thin films were fabricated, and we observed a 10-fold improvement in the external quantum efficiency of these LEDs (from 0.6% to 6.3%) resulting from the in situ formation of perovskite NCs with phosphonium passivation.

20.
ACS Appl Mater Interfaces ; 9(33): 27607-27617, 2017 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-28767213

RESUMEN

Platinum (Pt)-based alloys are considerably promising electrocatalysts for the reduction of I-/I3- and Co2+/Co3+ redox couples in dye-sensitized solar cells (DSSCs). However, it is still challenging to minimize the dosage of Pt to achieve comparable or even higher catalytic efficiency. Here, by taking full advantages of the Mott-Schottky (M-S) effect at the metal-semiconductor interface, we successfully strategize a low-Pt-based M-S catalyst with enhanced electrocatalytic performance and stability for the large-scale application of DSSCs. The optimized M-S electrocatalyst of Ni3S4-Pt2X1 (X = Fe, Ni) heteronanorods is constructed by rationally controlling the ratio of Pt to transition metal in the hybrids. It was found that the electrons transferred from Ni3S4 to Pt2X1 at their interface under the Mott-Schottky effect result in the concentration of electrons onto Pt2X1 domains, which subsequently accelerates the regeneration of both I-/I3- and Co2+/Co3+ redox shuttles in DSSCs. As a result, the DSSC with Ni3S4-Pt2Fe1 manifests an impressive power conversion efficiency (PCE) of 8.79% and 5.56% for iodine and cobalt-based electrolyte under AM1.5G illumination, respectively. These PCEs are obviously superior over those with Ni3S4-Pt, PtFe, Ni3S4, and pristine Pt electrodes. The strategy reported here is able to be further expanded to fabricate other low-Pt-alloyed M-S catalysts for wider applications in the fields of photocatalysis, water splitting, and heterojunction solar cells.

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