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1.
Nature ; 630(8015): 96-101, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750361

RESUMO

Chemical doping is an important approach to manipulating charge-carrier concentration and transport in organic semiconductors (OSCs)1-3 and ultimately enhances device performance4-7. However, conventional doping strategies often rely on the use of highly reactive (strong) dopants8-10, which are consumed during the doping process. Achieving efficient doping with weak and/or widely accessible dopants under mild conditions remains a considerable challenge. Here, we report a previously undescribed concept for the photocatalytic doping of OSCs that uses air as a weak oxidant (p-dopant) and operates at room temperature. This is a general approach that can be applied to various OSCs and photocatalysts, yielding electrical conductivities that exceed 3,000 S cm-1. We also demonstrate the successful photocatalytic reduction (n-doping) and simultaneous p-doping and n-doping of OSCs in which the organic salt used to maintain charge neutrality is the only chemical consumed. Our photocatalytic doping method offers great potential for advancing OSC doping and developing next-generation organic electronic devices.

2.
J Am Chem Soc ; 146(23): 15860-15868, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814791

RESUMO

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a benchmark hole-transporting (p-type) polymer that finds applications in diverse electronic devices. Most of its success is due to its facile synthesis in water, exceptional processability from aqueous solutions, and outstanding electrical performance in ambient. Applications in fields like (opto-)electronics, bioelectronics, and energy harvesting/storage devices often necessitate the complementary use of both p-type and n-type (electron-transporting) materials. However, the availability of n-type materials amenable to water-based polymerization and processing remains limited. Herein, we present a novel synthesis method enabling direct polymerization in water, yielding a highly conductive, water-processable n-type conjugated polymer, namely, poly[(2,2'-(2,5-dihydroxy-1,4-phenylene)diacetic acid)-stat-3,7-dihydrobenzo[1,2-b:4,5-b']difuran-2,6-dione] (PDADF), with remarkable electrical conductivity as high as 66 S cm-1, ranking among the highest for n-type polymers processed using green solvents. The new n-type polymer PDADF also exhibits outstanding stability, maintaining 90% of its initial conductivity after 146 days of storage in air. Our synthetic approach, along with the novel polymer it yields, promises significant advancements for the sustainable development of organic electronic materials and devices.

3.
Small ; 20(12): e2308216, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37946696

RESUMO

The ternary strategy is one of the effective methods to regulate the morphology of the active layer in organic solar cells (OSCs). In this work, the ternary OSCs with bulk heterojunction (BHJ) or layer-by-layer (LbL) active layers are prepared by using the polymer donor PM6 and the non-fullerene acceptor L8-BO as the main system and the fullerene acceptor PC71BM as the third component. The power conversion efficiencies (PCEs) of BHJ OSCs and LbL OSCs are increased from 17.10% to 18.02% and from 17.20% to 18.20% by introducing PC71BM into the binary active layer, respectively. The in situ UV-vis absorption spectra indicate that the molecular aggregation and crystallization process can be prolonged by introducing PC71BM into the PM6:L8-BO or PM6/L8-BO active layer. The molecular orientation and molecular crystallinity in the active layer are optimized by introducing the PC71BM into the binary BHJ or LbL active layers, which can be confirmed by the experimental results of grazing incidence wide-angle X-ray scattering. This study demonstrates that the third component PC71BM can be used as a morphology regulator to regulate the morphology of BHJ or LbL active layers, thus effectively improving the performance of BHJ and LbL OSCs.

4.
Small ; : e2404734, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966904

RESUMO

The morphology of the active layer is crucial for highly efficient organic solar cells (OSCs), which can be regulated by selecting a rational third component. In this work, the highly crystalline nonfullerene acceptor BTP-eC9 is selected as the morphology regulator in OSCs with PM6:BTP-BO-4Cl as the main system. The addition of BTP-eC9 can prolong the nucleation and crystallization progress of acceptor and donor molecules, thereby enhancing the order of molecular arrangement. Meanwhile, the nucleation and crystallization time of the donor is earlier than that of the acceptors after introducing BTP-eC9, which is beneficial for obtaining a better vertical structural phase separation. The exciton dissociation, charge transport, and charge collection are promoted effectively by the optimized morphology of the active layer, which improves the short-circuit current density and filling factor. After introducing BTP-eC9, the power conversion efficiencies (PCEs) of the ternary OSCs are improved from 17.31% to 18.15%. The PCE is further improved to 18.39% by introducing gold nanopyramid (Au NBPs) into the hole transport layer to improve photon utilization efficiency. This work indicates that the morphology can be optimized by selecting a highly crystalline third component to regulate the nucleation and crystallization progress of the acceptor and donor molecules.

5.
Small ; : e2403486, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-39031678

RESUMO

The development of high-performance organic photovoltaic materials is of crucial importance for the commercialization of organic solar cells (OSCs). Herein, two structurally simple donor-π-conjugated linker-acceptor (D-π-A)-configured small-molecule donors with methyl-substituted triphenylamine as D unit, 1,1-dicyanomethylene-3-indanone as A unit, and thiophene or furan as π-conjugated linker, named DTICPT and DTICPF, are developed. DTICPT and DTICPF are facilely prepared via a two-step synthetic process with simple procedures. DTICPF with a furan π-conjugated linker exhibits stronger and broader optical absorption, deeper highest occupied molecular orbital (HOMO) energy levels, and better charge transport, compared to its thiophene analog DTICPT. As a result, vacuum-deposited OSCs based on DTICPF: C70 show an impressive power conversion efficiency (PCE) of 9.36% (certified 9.15%) with short-circuit current density (Jsc) up to 17.49 mA cm-2 (certified 17.56 mA cm-2), which is the highest Jsc reported so far for vacuum-deposited OSCs. Besides, devices based on DTICPT: C70 and DTICPF: C70 exhibit excellent long-term stability under different aging conditions. This work offers important insights into the rational design of D-π-A configured small-molecule donors for high efficient and stable vacuum-deposited OSCs.

6.
Faraday Discuss ; 250(0): 335-347, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-37965681

RESUMO

The scarcity of n-type polymers with high electrical conductivity (σ) and power factor (PF) is the major challenge for organic thermoelectrics (OTEs). By integrating cyano functionalities and an intramolecular conformation lock, we herein synthesize a new electron-deficient building block, CNg4T2, bearing long 1,4,7,10-tetraoxahendecyl side chains, and then further develop two n-type polythiophene derivatives, CNg4T2-2FT and CNg4T2-CNT2, with 3,4-difluorothiophene and 3,3'-dicyano-2,2'-bithiophene as co-units, respectively. Compared with CNg4T2-2FT, CNg4T2-CNT2 features a deeper-positioned lowest unoccupied molecular orbital (LUMO) while maintaining a high degree of backbone coplanarity. As a consequence, the CNg4T2-CNT2 film with molecular dopant N-DMBI delivered an impressive σ of 13.2 S cm-1 and a high PF of up to 10.84 µW m-1 K-2, significantly outperforming CNg4T2-2FT and benchmark n-type polymer N2200 films. To the best of our knowledge, this PF of CNg4T2-CNT2 devices is the highest value for n-type polythiophenes in OTEs. Further characterizations indicate that the high performance of CNg4T2-CNT2-based devices is attributed to the high doping efficiency and ordered packing of polymer chains. Our study demonstrates that CNg4T2 is a highly appealing electron-deficient building block for n-type OTE polymers and also suggests that fine-tuning of the polymer backbone is a powerful approach to accessing high-performance n-type polymers for OTE devices.

7.
Angew Chem Int Ed Engl ; 63(3): e202316214, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37996990

RESUMO

Developing polymers with high electrical conductivity (σ) after n-doping is a great challenge for the advance of the field of organic thermoelectrics (OTEs). Herein, we report a series of thiazole imide-based n-type polymers by gradually increasing selenophene content in polymeric backbone. Thanks to the strong intramolecular noncovalent N⋅⋅⋅S interaction and enhanced intermolecular Se⋅⋅⋅Se interaction, with the increase of selenophene content, the polymers show gradually lowered LUMOs, more planar backbone, and improved film crystallinity versus the selenophene-free analogue. Consequently, polymer PDTzSI-Se with the highest selenophene content achieves a champion σ of 164.0 S cm-1 and a power factor of 49.0 µW m-1 K-2 in the series when applied in OTEs after n-doping. The σ value is the highest one for n-type donor-acceptor OTE materials reported to date. Our work indicates that selenophene substitution is a powerful strategy for developing high-performance n-type OTE materials and selenophene incorporated thiazole imides offer an excellent platform in enabling n-type polymers with high backbone coplanarity, deep-lying LUMO and enhanced mobility/conductivity.

8.
Angew Chem Int Ed Engl ; : e202408537, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973771

RESUMO

Achieving high electrical conductivity (σ) and power factor (PF) simultaneously remains a significant challenge for n-type organic themoelectrics (OTEs). Herein, we demonstrate the state-of-the-art OTEs performance through blending a fused bithiophene imide dimer-based polymer f-BTI2g-SVSCN and its selenophene-substituted analogue f-BSeI2g-SVSCN with a julolidine-functionalized benzimidazoline n-dopant JLBI, vis-à-vis when blended with commercially available n-dopants TAM and N-DMBI. The advantages of introducing a more lipophilic julolidine group into the dopant structure of JLBI are evidenced by the enhanced OTEs performance that JLBI-doped films show when compared to those doped with N-DMBI or TAM. In fact, thanks to the enhanced intermolecular interactions and the lower-lying LUMO level enabled by the increase of selenophene content in polymer backbone, JLBI-doped films of f-BSeI2g-SVSCN exhibit a unprecedent σ of 206 S cm-1 and a PF of 114 µW m-1 K-2. Interestingly, σ can be further enhanced up to 326 S cm-1 by using TAM dopant as a consequence of its favorable diffusion behavior into densely packed crystalline domains. These values are the highest to date for solution-processed molecularly n-doped polymers, demonstrating the effectiveness of the polymer-dopant matching approach carried out in this work.

9.
Angew Chem Int Ed Engl ; 63(17): e202319627, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38443313

RESUMO

High-performing n-type polymers are crucial for the advance of organic electronics field, however strong electron-deficient building blocks with optimized physicochemical properties for constructing them are still limited. The imide-functionalized polycyclic aromatic hydrocarbons (PAHs) with extended π-conjugated framework, high electron deficiency and good solubility serve as promising candidates for developing high-performance n-type polymers. Among the PAHs, phenanthrene (PhA) features a well-delocalized aromatic π-system with multiple modifiable active sites . However, the PhA-based imides are seldom studied, mainly attributed to the synthetic challenge. Herein, we report two functionalized PhAs, CPOI and CPCNI, by simultaneously incorporating imide with carbonyl or dicyanomethylene onto PhA. Notably, the dicyanomethylene-modified CPCNI exhibits a well stabilized LUMO energy level (-3.84 eV), attributed to the synergetic inductive effect from imide and cyano groups. Subsequently, based on CPOI and CPCNI, two polymers PCPOI-Tz and PCPCNI-Tz were developed. Applied to organic thin-film transistors, owing to the strong electron-deficiency of CPCNI, polymer PCPCNI-Tz shows an improved electron mobility and largely decreased threshold voltage compared with PCPOI-Tz. This work affords two structurally novel electron-deficient building blocks and highlights the effectiveness of dual functionalization of PhAs with strong electron-withdrawing groups for devising n-type polymers.

10.
Angew Chem Int Ed Engl ; : e202407273, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770935

RESUMO

A new approach to control the n-doping reaction of organic semiconductors is reported using surface-functionalized gold nanoparticles (f-AuNPs) with alkylthiols acting as the catalyst only upon mild thermal activation. To demonstrate the versatility of this methodology, the reaction of the n-type dopant precursor N-DMBI-H with several molecular and polymeric semiconductors at different temperatures with/without f-AuNPs, vis-à-vis the unfunctionalized catalyst AuNPs, was investigated by spectroscopic, morphological, charge transport, and kinetic measurements as well as, computationally, the thermodynamic of catalyst activation. The combined experimental and theoretical data demonstrate that while f-AuNPs is inactive at room temperature both in solution and in the solid state, catalyst activation occurs rapidly at mild temperatures (~70 °C) and the doping reaction completes in few seconds affording large electrical conductivities (~10-140 S cm-1). The implementation of this methodology enables the use of semiconductor+dopant+catalyst solutions and will broaden the use of the corresponding n-doped films in opto-electronic devices such as thin-film transistors, electrochemical transistors, solar cells, and thermoelectrics well as guide the design of new catalysts.

11.
Small ; 19(5): e2204905, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36446633

RESUMO

To separately explore the importance of hydrophilicity and backbone planarity of polymer photocatalyst, a series of benzothiadiazole-based donor-acceptor alternating copolymers incorporating alkoxy, linear oligo(ethylene glycol) (OEG) side chain, and backbone fluorine substituents is presented. The OEG side chains in the polymer backbone increase the surface energy of the polymer nanoparticles, thereby improving the interaction with water and facilitating electron transfer to water. Moreover, the OEG-attached copolymers exhibit enhanced intermolecular packing compared to polymers with alkoxy side chains, which is possibly attributed to the self-assembly properties of the side chains. Fluorine substituents on the polymer backbone produce highly ordered lamellar stacks with distinct π-π stacking features; subsequently, the long-lived polarons toward hydrogen evolution are observed by transient absorption spectroscopy. In addition, a new nanoparticle synthesis strategy using a methanol/water mixed solvent is first adopted, thereby avoiding the screening effect of surfactants between the nanoparticles and water. Finally, hydrogen evolution rate of 26 000 µmol g-1  h-1 is obtained for the copolymer incorporated with both OEG side chains and fluorine substituents under visible-light irradiation (λ > 420 nm). This study demonstrates how the glycol side chain strategy can be further optimized for polymer photocatalysts by controlling the backbone planarity.

12.
Angew Chem Int Ed Engl ; 62(45): e202302888, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37380618

RESUMO

The determination of molecular conformations of oligomeric acceptors (OAs) and their impact on molecular packing are crucial for understanding the photovoltaic performance of their resulting polymer solar cells (PSCs) but have not been well studied yet. Herein, we synthesized two dimeric acceptor materials, DIBP3F-Se and DIBP3F-S, which bridged two segments of Y6-derivatives by selenophene and thiophene, respectively. Theoretical simulation and experimental 1D and 2D NMR spectroscopic studies prove that both dimers exhibit O-shaped conformations other than S- or U-shaped counter-ones. Notably, this O-shaped conformation is likely governed by a distinctive "conformational lock" mechanism, arising from the intensified intramolecular π-π interactions among their two terminal groups within the dimers. PSCs based on DIBP3F-Se deliver a maximum efficiency of 18.09 %, outperforming DIBP3F-S-based cells (16.11 %) and ranking among the highest efficiencies for OA-based PSCs. This work demonstrates a facile method to obtain OA conformations and highlights the potential of dimeric acceptors for high-performance PSCs.

13.
Small ; 18(4): e2104215, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34841671

RESUMO

Although the rapid development of polymer solar cells (PSCs) has been achieved, it is still a great challenge to explore efficient ways for improving power conversion efficiency (PCE) of PSCs from materials and device engineering. Ternary strategy has been confirmed as an efficient way to improve PCE of PSCs by employing three kinds of materials. In this work, one polymer donor PM6, and two non-fullerene materials N3 and MF1 are selected to prepare ternary PSCs with layer-by-layer (LbL) or bulk-heterojunction (BHJ) structure. The LbL and BHJ-PSCs exhibit PCEs of 16.75% and 16.76% with 15 wt% MF1 content in acceptors, corresponding to over 5% or 4% PCE improvement compared with N3-based binary PSCs with LbL or BHJ structure. The PCE improvement is mainly attributed to the fill factor enhancement from 73.29% to 76.95% for LbL-PSCs or from 74.13% to 77.51% for BHJ-PSCs by employing the ternary strategy. This work indicates that ternary strategy has great potential in preparing highly efficient LbL-PSCs via simultaneously optimizing molecular arrangement and the thickness of each layer.

14.
Macromol Rapid Commun ; 43(15): e2200345, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35445480

RESUMO

A series of binary and ternary polymer solar cells (PSCs) is successfully fabricated. The optimal ternary PSCs achieve a power conversion efficiency (PCE) of 18.14%, benefiting from the increased short circuit current density (JSC ) of 26.53 mA cm-2 and fill factor (FF) of 78.51% in comparison with the JSC s (25.05 mA cm-2 and 25.65 mA cm-2 ) and the FFs (77.13% and 76.55%) of the corresponding binary PSCs. The photon harvesting ability of ternary active layers can be enhanced, which can be confirmed from the EQE spectral difference of the optimized ternary and binary PSCs, especially in the wavelength range from 680 nm to 800 nm. The refractive index and extinction coefficients of binary and ternary blend films are measured, which can well support the enhanced photon harvesting ability in different wavelength ranges. Photogenerated exciton distribution in active layers is simulated by the transmission matrix method based on the Beer-Lambert law. The photogenerated exciton density can be enhanced in the middle of the active layers by incorporating a third component in acceptors, which is conducive to charge collection by individual electrodes, resulting in the simultaneously enhanced JSC and FF of the optimal ternary PSCs.

15.
Angew Chem Int Ed Engl ; 61(51): e202214192, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36282628

RESUMO

n-Type semiconducting polymers with high thermoelectric performance remain challenging due to the scarcity of molecular design strategy, limiting their applications in organic thermoelectric (OTE) devices. Herein, we provide a new approach to enhance the OTE performance of n-doped polymers by introducing acceptor-acceptor (A-A) type backbone bearing branched ethylene glycol (EG) side chains. When doped with 4-(2,3-dihydro-1,3-dimethyl-1H-benzimidazol-2-yl)-N,N-dimethylbenzenamine (N-DMBI), the A-A homopolymer PDTzTI-TEG exhibits n-type electrical conductivity (σ) up to 34 S cm-1 and power factor value of 15.7 µW m-1 K-2 . The OTE performance of PDTzTI-TEG is far greater than that of homopolymer PBTI-TEG (σ=0.27 S cm-1 ), indicating that introducing electron-deficient thiazole units in the backbone further improves the n-doping efficiency. These results demonstrate that developing A-A type polymers with EG side chains is an effective strategy to enhance n-type OTE performance.

16.
Angew Chem Int Ed Engl ; 61(25): e202202177, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35383399

RESUMO

Enhancing the built-in electric field to promote charge dynamitic process is of great significance to boost the performance of the non-fullerene organic solar cells (OSCs), which has rarely been concerned. In this work, we introduced a cheap ferroelectric polymer as an additive into the active layers of non-fullerene OSCs to improve the device performance. An additional and permanent electrical field was produced by the polarization of the ferroelectric dipoles, which can substantially enhance the built-in electric field. The promoted exciton separation, significantly accelerated charge transport, reduced the charge recombination, as well as the optimized film morphology were observed in the device, leading to a significantly improved performance of the PVDF-modified OSCs with various active layers, such as PM6 : Y6, PM6 : BTP-eC9, PM6 : IT-4F and PTB7-Th : Y6. Especially, a record efficiency of 17.72 % for PM6 : Y6-based OSC and an outstanding efficiency of 18.17 % for PM6 : BTP-eC9-based OSC were achieved.

17.
Stem Cells ; 33(11): 3291-303, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26235673

RESUMO

Previous studies have shown that mesenchymal stem cell (MSC)-based therapies have varying efficacies for the treatment of various diseases, including cartilage defects. In this study, we demonstrated that the chondrogenic differentiation potential of human umbilical cord blood-derived MSCs (hUCB-MSCs) obtained from different individual donors varies, and we investigated the molecular basis for this variation. Microarray gene expression analysis identified thrombospondin-2 (TSP2) as a candidate gene underlying the interindividual variation in the chondrogenic differentiation potential of hUCB-MSCs. To assess the association between TSP-2 and the differentiation potential, we evaluated chondrogenic differentiation of hUCB-MSCs treated with TSP2 siRNA. In addition, we studied the effect of supplementing exogenous recombinant TSP-2 on TSP2 siRNA-treated hUCB-MSCs. We found that TSP-2 autocrinally promoted chondrogenic differentiation of hUCB-MSCs via the Notch signaling pathway, which was confirmed in MSCs from other sources such as bone marrow and adipose tissue. Interestingly, we observed that TSP-2 attenuated hypertrophy, which inevitably occurs during chondrogenic differentiation of hUCB-MSCs. Our findings indicated that the variable chondrogenic differentiation potential of MSCs obtained from different donors is influenced by the TSP-2 level in the differentiating cells. Thus, the TSP-2 level can be used as a marker to select MSCs with superior chondrogenic differentiation potential for use in cartilage regeneration therapy.


Assuntos
Comunicação Autócrina/fisiologia , Diferenciação Celular/fisiologia , Condrogênese/fisiologia , Sangue Fetal/metabolismo , Células-Tronco Mesenquimais/metabolismo , Trombospondinas/metabolismo , Células Cultivadas , Humanos , Hipertrofia , Recém-Nascido
18.
Biochem Biophys Res Commun ; 446(4): 983-9, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24657442

RESUMO

Evaluation of the immunogenicity of human mesenchymal stem cells (MSCs) in an allogeneic setting during therapy has been hampered by lack of suitable models due to technical and ethical limitations. Here, we show that allogeneic human umbilical cord blood derived-MSCs (hUCB-MSCs) maintained low immunogenicity even after immune challenge in vitro. To confirm these properties in vivo, a humanized mouse model was established by injecting isolated hUCB-derived CD34+ cells intravenously into immunocompromised NOD/SCID IL2γnull (NSG) mice. After repeated intravenous injection of human peripheral blood mononuclear cells (hPBMCs) or MRC5 cells into these mice, immunological alterations including T cell proliferation and increased IFN-γ, TNF-α, and human IgG levels, were observed. In contrast, hUCB-MSC injection did not elicit these responses. While lymphocyte infiltration in the lung and small intestine and reduced survival rates were observed after hPBMC or MRC5 transplantation, no adverse events were observed following hUCB-MSC introduction. In conclusion, our data suggest that allogeneic hUCB-MSCs have low immunogenicity in vitro and in vivo, and are therefore "immunologically safe" for use in allogeneic clinical applications.


Assuntos
Sangue Fetal/citologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/imunologia , Animais , Antígenos CD34/análise , Células Cultivadas , Modelos Animais de Doenças , Humanos , Imunoglobulina G/imunologia , Interferon gama/imunologia , Ativação Linfocitária , Camundongos , Camundongos SCID , Fator de Necrose Tumoral alfa/imunologia
19.
Stem Cells ; 31(10): 2136-48, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23843355

RESUMO

Increasing evidence indicates that the secretome of mesenchymal stem cells (MSCs) has therapeutic potential for the treatment of various diseases, including cartilage disorders. However, the paracrine mechanisms underlying cartilage repair by MSCs are poorly understood. Here, we show that human umbilical cord blood-derived MSCs (hUCB-MSCs) promoted differentiation of chondroprogenitor cells by paracrine action. This paracrine effect of hUCB-MSCs on chondroprogenitor cells was increased by treatment with synovial fluid (SF) obtained from osteoarthritis (OA) patients but was decreased by SF of fracture patients, compared to that of an untreated group. To identify paracrine factors underlying the chondrogenic effect of hUCB-MSCs, the secretomes of hUCB-MSCs stimulated by OA SF or fracture SF were analyzed using a biotin label-based antibody array. Among the proteins increased in response to these two kinds of SF, thrombospondin-2 (TSP-2) was specifically increased in only OA SF-treated hUCB-MSCs. In order to determine the role of TSP-2, exogenous TSP-2 was added to a micromass culture of chondroprogenitor cells. We found that TSP-2 had chondrogenic effects on chondroprogenitor cells via PKCα, ERK, p38/MAPK, and Notch signaling pathways. Knockdown of TSP-2 expression on hUCB-MSCs using small interfering RNA abolished the chondrogenic effects of hUCB-MSCs on chondroprogenitor cells. In parallel with in vitro analysis, the cartilage regenerating effect of hUCB-MSCs and TSP-2 was also demonstrated using a rabbit full-thickness osteochondral-defect model. Our findings suggested that hUCB-MSCs can stimulate the differentiation of locally presented endogenous chondroprogenitor cells by TSP-2, which finally leads to cartilage regeneration.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Trombospondinas/metabolismo , Adulto , Idoso , Animais , Cartilagem Articular/patologia , Cartilagem Articular/fisiopatologia , Células Cultivadas , Técnicas de Cocultura , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Pessoa de Meia-Idade , Osteoartrite do Joelho/tratamento farmacológico , Osteoartrite do Joelho/patologia , Coelhos , Regeneração , Medicina Regenerativa , Líquido Sinovial/fisiologia , Trombospondinas/fisiologia , Trombospondinas/uso terapêutico
20.
Adv Mater ; 36(4): e2305416, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37572077

RESUMO

Developing high-performance n-type polymer mixed ionic-electronic conductors (PMIECs) is a grand challenge, which largely determines their applications in vaious organic electronic devices, such as organic electrochemical transistors (OECTs) and organic thermoelectrics (OTEs). Herein, two halogen-functionalized PMIECs f-BTI2g-TVTF and f-BTI2g-TVTCl built from fused bithiophene imide dimer (f-BTI2) as the acceptor unit and halogenated thienylene-vinylene-thienylene (TVT) as the donor co-unit are reported. Compared to the control polymer f-BTI2g-TVT, the fluorinated f-BTI2g-TVTF shows lower-positioned lowest unoccupied molecular orbital (LUMO), improved charge transport property, and greater ion uptake capacity. Consequently, f-BTI2g-TVTF delivers a state-of-the-art µC* of 90.2 F cm-1 V-1 s-1 with a remarkable electron mobility of 0.41 cm2 V-1 s-1 in OECTs and an excellent power factor of 64.2 µW m-1 K-2 in OTEs. An OECT-based inverter amplifier is further demonstrated with voltage gain up to 148 V V-1 , which is among the highest values for OECT inverters. Such results shed light on the impacts of halogen atoms on developing high-performing n-type PMIECs.

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