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1.
Anal Chem ; 96(16): 6218-6227, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38598863

RESUMO

Currently reported aggregation-induced electroluminescence (AIECL) is usually based on the electrostatic integration of luminous monomers, and its application is still limited by the low ECL efficiency and poor structural stability of electrostatic integration-based AIECL emitters. Herein, host-guest recognition-mediated supramolecular AIECL was creatively developed to overcome the defects of electrostatic-integration-based AIECL. Cucurbit[8]uril (CB[8]) as the host recognized tris (2-phenylpyridine) iridium(III) [Ir(ppy)3] as the guest to form a novel supramolecular complex Ir-CB[8]. CB[8] can not only provide a large hydrophobic cavity to efficiently load Ir(ppy)3 and enrich coreactant tripropylamine but also utilize its carbonyl-laced portals to form intramolecular hydrogen bonds to stabilize the supramolecular structure, so Ir-CB[8] revealed excellent AIECL performance. The AIECL emitter Ir-CB[8] coupled the efficient DNA walker to construct a sensing system for miRNA-16 detection. Au nanoparticles@norepinephrine (AuNPs@NE) trapped by single-strand S1 was developed to significantly quench the ECL emission of Ir-CB[8]. When the target microRNA-16 (miRNA-16) existed, H1 was opened and the sequential assembly from H2 to H7 was triggered, forming "windmill"-like DNA walker with six Pb2+-dependent leg DNA. The assembled DNA walker, which was centered on DNA structure, had high efficiency and biocompatibility and can cut S1 to keep the DNA fragment-carrying quencher AuNPs@NE away from the electrode surface, thus restoring the ECL emission of Ir-CB[8] and realizing ultrasensitive detection of miRNA-16. Supramolecular AIECL mediated by host-guest recognition provides a new way for constructing AIECL emitters with excellent structural stability and AIECL efficiency, and an Ir-CB[8] coupling "windmill"-like DNA walker builds a promising ECL-sensing system for bioassay.

2.
Polymers (Basel) ; 16(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611201

RESUMO

In order to develop flexible thermoelectric materials with thermoelectric and mechanical properties, in this study, we designed and synthesized polythiophene derivatives with branched ethylene glycol polar side-chains named P3MBTEMT, which were used in combination with single-walled carbon nanotubes (SWCNTs) to prepare composite thin films and flexible thermoelectric devices. A comparison was made with a polymer named P3(TEG)T, which has a polar alkoxy linear chain. The UV-vis results indicated that the larger steric hindrances of the branched ethylene glycol side-chain in P3MBTEMT could inhibit its self-aggregation and had a stronger interaction with the SWCNTs compared to that of P3(TEG)T, which was also confirmed using Raman spectroscopy. When the mass ratio of SWCNTs to P3MBTEMT was 9:1 (represented as P3MBTEMT/SWCNTs-0.9), the composite film exhibited the highest thermoelectric properties with a power factor of 446.98 µW m-1 K-2, which was more than two times higher than that of P3(TEG)T/SWCNTs-0.9 (215.08 µW m-1 K-2). The output power of the thermoelectric device with P3MBTEMT/SWCNTs-0.9 was 2483.92 nW at 50 K, which was 1.66 times higher than that of P3(TEG)T/SWCNTs-0.9 (1492.65 nW). Furthermore, the P3MBTEMT/SWCNTs-0.5 showed superior mechanical properties compared to P3(TEG)T/SWCNTs-0.5. These results indicated that the mechanical and thermoelectric performances of polymer/SWCNT composites could be significantly improved by adding polar branched side-chains to conjugated polymers. This study provided a new strategy for creating high-performing novel flexible thermoelectric materials.

3.
ACS Sens ; 9(4): 1945-1956, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530950

RESUMO

Urinary tract infections (UTIs), which can lead to pyelonephritis, urosepsis, and even death, are among the most prevalent infectious diseases worldwide, with a notable increase in treatment costs due to the emergence of drug-resistant pathogens. Current diagnostic strategies for UTIs, such as urine culture and flow cytometry, require time-consuming protocols and expensive equipment. We present here a machine learning-assisted colorimetric sensor array based on recognition of ligand-functionalized Fe single-atom nanozymes (SANs) for the identification of microorganisms at the order, genus, and species levels. Colorimetric sensor arrays are built from the SAN Fe1-NC functionalized with four types of recognition ligands, generating unique microbial identification fingerprints. By integrating the colorimetric sensor arrays with a trained computational classification model, the platform can identify more than 10 microorganisms in UTI urine samples within 1 h. Diagnostic accuracy of up to 97% was achieved in 60 UTI clinical samples, holding great potential for translation into clinical practice applications.


Assuntos
Colorimetria , Aprendizado de Máquina , Infecções Urinárias , Infecções Urinárias/diagnóstico , Infecções Urinárias/microbiologia , Infecções Urinárias/urina , Colorimetria/métodos , Humanos , Ferro/química , Técnicas Biossensoriais/métodos
4.
Nat Commun ; 15(1): 1190, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331933

RESUMO

The mechanisms underlying glucocorticoid (GC)-induced obesity are poorly understood. Macrophages are the primary targets by which GCs exert pharmacological effects and perform critical functions in adipose tissue homeostasis. Here, we show that macrophages are essential for GC-induced obesity. Dexamethasone (Dex) strongly induced Krüppel-like factor 9 (Klf9) expression in macrophages. Similar to Dex, lentivirus-mediated Klf9 overexpression inhibits M1 and M2a markers expression, causing macrophage deactivation. Furthermore, the myeloid-specific Klf9 transgene promotes obesity. Conversely, myeloid-specific Klf9-knockout (mKlf9KO) mice are lean. Moreover, myeloid Klf9 knockout largely blocks obesity induced by chronic GC treatment. Mechanistically, GC-inducible KLF9 recruits the SIN3A/HDAC complex to the promoter regions of Il6, Ptgs2, Il10, Arg1, and Chil3 to inhibit their expression, subsequently reducing thermogenesis and increasing lipid accumulation by inhibiting STAT3 signaling in adipocytes. Thus, KLF9 in macrophages integrates the beneficial anti-inflammatory and adverse metabolic effects of GCs and represents a potential target for therapeutic interventions.


Assuntos
Adiposidade , Glucocorticoides , Animais , Camundongos , Glucocorticoides/farmacologia , Glucocorticoides/metabolismo , Obesidade/genética , Obesidade/metabolismo , Macrófagos/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo
5.
J Affect Disord ; 349: 132-144, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38211741

RESUMO

BACKGROUND: Synaptic plasticity changes in presynaptic terminals or postsynaptic membranes play a critical role in cognitive impairments and emotional disorders, but the underlying molecular mechanisms in depression remain largely unknown. METHODS: The regulation effects of F-box and leucine-rich repeat protein 20 (FBXL20), vesicular glutamate transporter 1 (VGLUT1) and vesicle-associated membrane protein 1 (VAMP1) on synaptic plasticity and depressive-like behaviors examined by proteomics analysis, viral stereotaxic injection, transmission electron microscope and biochemical methods. The glutamate release detected by fluorescent probe in cultured primary pyramidal neurons. RESULTS: We found that chronic unpredictable mild stress (CUMS) induced significant synaptic deficits within hippocampus of depressed rats, accompanied with the decreased expression of VGLUT1 and VAMP1. Moreover, knockdown of VGLUT1 or VAMP1 in hippocampal pyramidal neurons resulted in abnormal glutamatergic neurotransmitter release. In addition, we found that the E3 ubiquitin ligase FBXL20 was increased within hippocampus, which may promote ubiquitination and degradation of VGLUT1 and VAMP1, and thus resulted in the reduction of glutamatergic neurotransmitter release, the disruptions of synaptic transmission and the induction of depression-like behaviors in rats. In contrast, shRNA knockdown of FBXL20 within the hippocampus of depressed rats significantly ameliorated synaptic damage and depression-like behaviors. LIMITATION: Only one type of depression model was used in the present study, while other animal models should be used in the future to confirm the underlying mechanisms reported here. CONCLUSIONS: This study provides new insights that inhibiting FBXL20 pathway in depressed rats may be an effective strategy to rescue synaptic transmission and depression-like behaviors.


Assuntos
Depressão , Proteína 1 Associada à Membrana da Vesícula , Animais , Ratos , Depressão/metabolismo , Hipocampo/metabolismo , Neurotransmissores , Transmissão Sináptica , Proteína 1 Associada à Membrana da Vesícula/metabolismo
6.
Anal Chem ; 96(4): 1427-1435, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38226591

RESUMO

Although porphyrins make up a promising class of electrochemiluminescence (ECL) luminophors, their aggregation-caused quenching (ACQ) characteristics lead to inferior ECL efficiency (ΦECL). Furthermore, current application of porphyrins is limited to cathodic emission. This work creatively exploited a cage-like porous complex (referred to as SWU-1) as the microreactor to recede the ACQ effect while modulating dual ECL emission of meso-tetra(4-carboxyphenyl)porphine (TCPP), which self-assembled with SWU-1 to form TCPP@SWU-1 nanocapsules (TCPP@SWU-1 NCs). As the microreactor, SWU-1 not only effectively constrained TCPP aggregation to improve electron-hole recombination efficiency but also improved stability of anion and cation radicals, thus significantly enhancing the dual emission of TCPP. Compared with TCPP aggregates, the resulting TCPP@SWU-1 NCs exhibited significantly enhanced anodic and cathodic emission, and their ΦECL was increased by 8.7-fold and 3.9-fold, respectively. Furthermore, black hole quencher-2 (BHQ2) can simultaneously quench anodic and cathodic signals. TCPP@SWU-1 NCs coupling BHQ2 conveniently achieved an ECL ratio detection of miRNA-126, and the limit of detection (S/N = 3) was 4.1 aM. This work pioneered the development of the cage-like porous complex SWU-1 as the microreactor to alleviate defects of the ACQ effect and mediate dual emission of TCPP. The coupling of dual-emitting TCPP@SWU-1 NCs and dual-function moderator BHQ2 created a novel single-luminophor-based ratio system for bioanalysis and provided a promising ECL analysis approach for miRNA-126.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Porfirinas , Porosidade , Fotometria , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos
7.
Int J Biol Macromol ; 259(Pt 2): 129310, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38216014

RESUMO

Developing biobased materials is a considerably effective approach to save fossil resources and reduce emissions. Biobased polyamide 56 (PA56) is an excellent engineering material, but it has low toughness. Herein, to enhance the toughness of PA56, an ultra-tough biodegradable material, i.e., poly (butylene adipate-co-terephthalate) (PBAT) was introduced into PA56. Moreover, a self-synthesized epoxy-terminated hyperbranched polyester (EHBP) was used to improve the compatibility of the blended materials. The results of differential scanning calorimetry and Fourier-transform infrared spectroscopy indicated that the epoxide group of EHBP could react with PA56 and PBAT to form a block-like polymer structure and limit the crystallization behavior of the blends. The scanning electron microscopy results show that the addition of EHBP considerably reduced the dispersed-phase size in the blends, forming a nanoscale island structure. Moreover, the hydrogen bonds formed between EHBP and PA56/PBAT enhanced the intermolecular interaction between the two materials. Thus, PA56 blends with ultrahigh toughness were successfully prepared. The prepared PA56/PBAT/EHBP blend exhibited a notch impact strength of 20.71 kJ/m2 and a breaking elongation of 38.3 %, which represent increases of 427.3 % and 252.8 %, respectively, compared with those of pure PA56. Thus, the proposed method is suitable for toughening PA56 and broadening its applications.


Assuntos
Alcenos , Nylons , Ácidos Ftálicos , Polímeros , Poliésteres , Adipatos , Poli A
8.
Brain Res ; 1822: 148670, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37944571

RESUMO

BACKGROUND: Several studies have shown that retinol-binding protein (RBP) is linked to diabetes and neurodegenerative diseases. However, no studies have elucidated the relationship between RBP and diabetic cognitive disorders. OBJECTIVE: To determine whether the change characteristics of serum RBP are associated with alterations in cognitive functioning in type 2 diabetes mellitus (T2DM). METHODS: In this study, 252 patients with T2DM and 34 people as healthy controls were included. According to the Montreal Cognitive Assessment (MoCA), the diabetic subjects were divided into the mild cognitive impairment (MCI) group and the Non-MCI group. Demographic characteristics and clinical indicators as well as serum RBP levels were analyzed. RESULTS: The serum RBP levels in the MCI group were lower compared with the Non-MCI group (P = 0.02). The level of RBP was higher in the diabetes without MCI group than in the healthy control (P < 0.001). Serum RBP levels were positively correlated with MoCA scores (r = 0.178, P = 0.003). Binary Logistic regression model analysis showed that low RBP [odds ratio (OR) = 0.936], old age (OR = 1.074), high fasting blood glucose (OR = 1.164), and low fasting C-peptide (OR = 0.722) may be independent risk factors for diabetic MCI. The ROC curve of serum RBP for predicting diabetic MCI showed that the area under the curve was 0.630. CONCLUSIONS: Our study revealed an association between serum RBP and diabetic MCI. Serum RBP levels in diabetic MCI are lower and correlated with cognitive function.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Proteínas de Ligação ao Retinol , Humanos , Cognição , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Proteínas de Ligação ao Retinol/análise , Fatores de Risco
9.
Nano Lett ; 24(1): 339-346, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38147355

RESUMO

Moiré superlattices have emerged as an unprecedented manipulation tool for engineering correlated quantum phenomena in van der Waals heterostructures. With moiré potentials as a naturally configurable solid-state that sustains high exciton density, interlayer excitons in transition metal dichalcogenide heterostructures are expected to achieve high-temperature exciton condensation. However, the exciton degeneracy state is usually optically inactive due to the finite momentum of interlayer excitons. Experimental observation of dark interlayer excitons in moiré potentials remains challenging. Here we directly visualize the dark interlayer exciton transport in WS2/h-BN/WSe2 heterostructures using femtosecond transient absorption microscopy. We observe a transition from classical free exciton gas to quantum degeneracy by imaging temperature-dependent exciton transport. Below a critical degeneracy temperature, exciton diffusion rates exhibit an accelerating downward trend, which can be explained well by a nonlinear quantum diffusion model. These results open the door to quantum information processing and high-precision metrology in moiré superlattices.

10.
Redox Biol ; 69: 102996, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38103341

RESUMO

Diabetic encephalopathy (DE) is a common central nervous system complication of diabetes mellitus without effective therapy currently. Recent studies have highlighted synaptic mitochondrial damages as a possible pathological basis for DE, but the underlying mechanisms remain unclear. Our previous work has revealed that phosphatidate phosphatase Lipin1, a critical enzyme involved with phospholipid synthesis, is closely related to the pathogenesis of DE. Here, we demonstrate that Lipin1 is significantly down-regulated in rat hippocampus of DE. Knock-down of Lipin1 within hippocampus of normal rats induces dysregulation of homeostasis in synaptic mitochondrial dynamics with an increase of mitochondrial fission and a decrease of fusion, then causes synaptic mitochondrial dysfunction, synaptic plasticity deficits as well as cognitive impairments, similar to that observed in response to chronic hyperglycemia exposure. In contrast, an up-regulation of Lipin1 within hippocampus in the DE model ameliorates this cascade of dysfunction. We also find that the effect of Lipin1 that regulating mitochondrial dynamics results from maintaining appropriate phospholipid components in the mitochondrial membrane. In conclusion, alterations in hippocampal Lipin1 contribute to hippocampal synaptic mitochondrial dysfunction and cognitive deficits observed in DE. Targeting Lipin1 might be a potential therapeutic strategy for the clinical treatment of DE.


Assuntos
Encefalopatias , Diabetes Mellitus , Hipoglicemia , Doenças Mitocondriais , Animais , Ratos , Hipocampo/metabolismo , Dinâmica Mitocondrial , Fosfatidato Fosfatase/genética , Fosfatidato Fosfatase/metabolismo , Fosfolipídeos
11.
Anal Chem ; 95(49): 18207-18214, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38010370

RESUMO

Owing to excellent catalytic activity, single-atom catalysts (SACs) have recently attracted considerable research interest in the electrochemiluminescence (ECL) field. However, the applications of SACs are mostly limited to conventional luminol ECL system. Hence, it is necessary to explore the application of SACs in more ECL systems. In this work, nickel single-atom catalysts (Ni SACs) were successfully applied in the graphitic carbon nitride (g-C3N4)-H2O2 ECL system to significantly enhance its cathodic emission. Notably, g-C3N4 acted not only as an ECL luminophore but also as a support to anchor Ni SACs. Ni SACs can significantly activate H2O2 to produce abundant OH• radicals for enhancing the cathodic ECL emission of g-C3N4. Ni SACs-anchored g-C3N4 (Ni SACs@g-C3N4) had a 10-fold enhanced ECL intensity as compared to g-C3N4. Finally, the Ni SACs@g-C3N4-H2O2 ECL system was developed to detect hepatitis B virus (HBV) DNA by incorporating an entropy-driven DNA walking machine-assisted CRISPR-Cas12a amplification strategy. The constructed biosensor exhibited excellent detection performance for HBV DNA with a limit of detection as low as 17 aM. This work puts forward a new idea for enhancing the cathodic ECL of g-C3N4-H2O2 and expands the application of SACs in the ECL system.


Assuntos
Técnicas Biossensoriais , DNA Viral , Níquel , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Medições Luminescentes , Limite de Detecção
12.
Cell Genom ; 3(11): 100364, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38020968

RESUMO

Aneuploidy compromises genomic stability, often leading to embryo inviability, and is frequently associated with tumorigenesis and aging. Different aneuploid chromosome stoichiometries lead to distinct transcriptomic and phenotypic changes, making it helpful to study aneuploidy in tightly controlled genetic backgrounds. By deploying the engineered SCRaMbLE (synthetic chromosome rearrangement and modification by loxP-mediated evolution) system to the newly synthesized megabase Sc2.0 chromosome VII (synVII), we constructed a synthetic disomic yeast and screened hundreds of SCRaMbLEd derivatives with diverse chromosomal rearrangements. Phenotypic characterization and multi-omics analysis revealed that fitness defects associated with aneuploidy could be restored by (1) removing most of the chromosome content or (2) modifying specific regions in the duplicated chromosome. These findings indicate that both chromosome copy number and specific chromosomal regions contribute to the aneuploidy-related phenotypes, and the synthetic chromosome resource opens new paradigms in studying aneuploidy.

14.
Heliyon ; 9(8): e18368, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37609411

RESUMO

One of the most common chronic complications arising from diabetes is diabetic peripheral neuropathy. Depending on research statistics, approximately half of the people who have diabetes will suffer from diabetic peripheral neuropathy over time, which manifests as abnormal sensations in the distal extremities, and about 25%-50% of these patients have symptoms of neuralgia, called painful diabetic neuropathy. These patients often exhibit adverse emotional conditions, like anxiety or depression, which can reduce their quality of life. The pathogenesis of diabetic peripheral neuropathy is complex, and although persistent hyperglycemia plays a central role in the development of diabetic peripheral neuropathy, strict glycemic control does not eliminate the risk of diabetic peripheral neuropathy. This suggests the need to understand the role of the central nervous system in the development of diabetic peripheral neuropathy to modulate treatment regimens accordingly. Magnetic resonance imaging not only allows for the noninvasive detection of structural and functional alterations in the central nervous system, but also provides insight into the processing of abnormal information such as pain by the central nervous system, and most importantly, contributes to the development of more effective pain relief protocols. Therefore, this article will focus on the mechanisms and related imaging evidence of central alterations in diabetic peripheral neuropathy, especially in painful diabetic neuropathy.

15.
Food Funct ; 14(15): 7222-7239, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37464840

RESUMO

Depression is a common psychological disease accompanied by mental disorders and somatic symptoms. However, the underlying mechanisms regarding the pathogenesis of depression are still not clear. Neuronal damage resulting from inflammation is considered to be one of the important risk factors for depression. Ginsenoside-Rg1, a sterol extract extracted from ginseng herbs, has been shown to have neuroprotective effects against neurodegenerative diseases. Moreover, running exercise, a simple behavioral therapy, has been recently shown to have antidepressant effects. However, whether these two synergized strategies are more efficient in depression treatment, especially the neural mechanisms underlying this practical and interesting treatment is unknown. In this study, we have shown that ginsenoside-Rg1 synergized with voluntary running exercise exerts more efficiency on suppressing neuroinflammation, up-regulating expression of neurotrophic factors, and synaptic-related proteins, ameliorating neuronal structural damages than that of ginsenoside-Rg1 or voluntary exercise alone, suggesting its better neuroprotective effects. More importantly, the antidepressant-like effect of this synergistic treatment was also significantly better than either of these two treatments. These results suggest that ginsenoside-Rg1, synergized with voluntary running, may have higher efficacy in the treatment of depression through anti-inflammation and the improvement of neuroplasticity. These findings may provide a new perspective for the development of a therapeutic strategy for depression.

16.
ACS Nano ; 17(14): 14161-14175, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37406357

RESUMO

The oral form of insulin is more convenient and has better patient compliance than subcutaneous or intravenous insulin. Current oral insulin preparations, however, cannot overcome the enzyme barrier, chemical barrier, and epithelial barrier of the gastrointestinal tract completely. In this study, a microalgae-based oral insulin delivery strategy (CV@INS@ALG) was developed using Chlorella vulgaris (CV)-based insulin delivery system cross-linking with sodium alginate (ALG). CV@INS@ALG could overcome the gastrointestinal barrier, protect insulin from harsh gastric conditions, and achieve a pH-responsive drug release in the intestine. CV@INS@ALG might contribute to two mechanisms of insulin absorption, including direct insulin release from the delivery system and endocytosis by M cells and macrophages. In the streptozotocin (STZ)-induced type 1 diabetic mouse model, CV@INS@ALG showed a more effective and long-lasting hypoglycemic effect than direct insulin injection and did not cause any damage to the intestinal tract. Additionally, the long-term oral administration of the carrier CV@ALG effectively ameliorated gut microbiota disorder, and significantly increased the abundance of probiotic Akkermansia in db/db type 2 diabetic mice, thereby enhancing the insulin sensitivity of mice. Microalgal insulin delivery systems could be degraded and metabolized in the intestinal tract after oral administration, showing good biodegradability and biosafety. This insulin delivery strategy based on microalgal biomaterials provides a natural, efficient, and multifunctional solution for oral insulin delivery.


Assuntos
Chlorella vulgaris , Diabetes Mellitus Experimental , Microalgas , Humanos , Camundongos , Animais , Insulina , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Hidrogéis/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/uso terapêutico , Concentração de Íons de Hidrogênio , Administração Oral , Sistemas de Liberação de Medicamentos
17.
Biosens Bioelectron ; 237: 115539, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37487285

RESUMO

Constructing mono-luminophor-based electrochemiluminescence (ECL) ratio system is a great challenge due to the limitations of the luminescent species with dual-signal-output, luminescence efficiency and coreactant. This work developed carboxyl-functionalized poly[9,9-bis(3'-(N,N-dimethylamino) propyl)-2,7-fluorene]-alt-2,7-(9,9 dioctylfluorene)] nanoparticles(PFN NPs) as dual-emitting luminophors, which can synchronously output strong cathodic and anodic ECL signals without any exogenous coreactants. The inherent molecular structure enabled efficient intramolecular electron transfer between tertiary amine groups and backbone of PFN to generate strong cathodic and anodic ECL emission. Particularly, H+ in aqueous solution played an irreplaceable role for cathodic ECL emission. The silver nanoparticles (AgNPs) were developed as signal regulator because of their excellent hydrogen evolution reaction (HER) activity, which significantly quenched the cathodic signal while kept the anodic signal unchanged. The dual-emitting PFN NPs cleverly integrated signal regulator AgNPs and bicyclic strand displacement amplification (SDA) to construct a coreactant-free mono-luminophor-based ratiometric ECL sensing for SARS-CoV-2 RdRp gene assay. The strong dual-emitting of PFN NPs and excellent quenching effect of AgNPs on cathodic emission endowed the biosensor with a high detection sensitivity, and the detection limit was as low as 39 aM for RdRp gene. The unique dual-emitting properties of PFN NPs open up a new path to construct coreactant-free mono-luminophor-based ECL ratio platform, and excellent HER activity of AgNPs offers some new thoughts for realizing ECL signal changes.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Humanos , Polímeros/química , Nanopartículas Metálicas/química , SARS-CoV-2/genética , Medições Luminescentes , COVID-19/diagnóstico , Prata , RNA Polimerase Dependente de RNA , Técnicas Eletroquímicas
18.
Genes (Basel) ; 14(6)2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37372321

RESUMO

Background: Colon cancer (CC) is common, and the mortality rate greatly increases as the disease progresses to the metastatic stage. Early detection of metastatic colon cancer (mCC) is crucial for reducing the mortality rate. Most previous studies have focused on the top-ranked differentially expressed transcriptomic biomarkers between mCC and primary CC while ignoring non-differentially expressed genes. Results: This study proposed that the complicated inter-feature correlations could be quantitatively formulated as a complementary transcriptomic view. We used a regression model to formulate the correlation between the expression levels of a messenger RNA (mRNA) and its regulatory transcription factors (TFs). The change between the predicted and real expression levels of a query mRNA was defined as the mqTrans value in the given sample, reflecting transcription regulatory changes compared with the model-training samples. A dark biomarker in mCC is defined as an mRNA gene that is non-differentially expressed in mCC but demonstrates mqTrans values significantly associated with mCC. This study detected seven dark biomarkers using 805 samples from three independent datasets. Evidence from the literature supports the role of some of these dark biomarkers. Conclusions: This study presented a complementary high-dimensional analysis procedure for transcriptome-based biomarker investigations with a case study on mCC.


Assuntos
Neoplasias do Colo , Perfilação da Expressão Gênica , Humanos , Biomarcadores , Perfilação da Expressão Gênica/métodos , Transcriptoma/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , RNA Mensageiro/genética
19.
Anal Chem ; 95(26): 10068-10076, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37339328

RESUMO

Improving the electrochemiluminescence (ECL) efficiency of luminophores has always been the goal of the ECL field. Herein, a novel crystallization-induced enhanced ECL (CIE ECL) strategy was exploited to significantly enhance the ECL efficiency of metal complex tris-(8-hydroxyquinoline)aluminum (Alq3). Alq3 monomers self-assembled and directionally grew to form Alq3 microcrystals (Alq3 MCs) in the presence of sodium dodecyl sulfate. The highly ordered crystal structure of Alq3 MCs not only constrained the intramolecular rotation of Alq3 monomers to decrease nonradiative transition but also accelerated the electron transfer between Alq3 MCs and coreactant tripropylamine to increase radiative transition, thus leading to a CIE ECL effect. Alq3 MCs exhibited brilliant anode ECL emission, which was 210-fold stronger than that of Alq3 monomers. The exceptional CIE ECL performance of Alq3 MCs coupled the efficient trans-cleavage activity of CRISPR/Cas12a assisted by rolling circle amplification and catalytic hairpin assembly to fabricate a CRISPR/Cas12a-mediated aptasensor for acetamiprid (ACE) detection. The limit of detection was as low as 0.79 fM. This work not only innovatively exploited a CIE ECL strategy to enhance the ECL efficiency of metal complexes but also integrated CRISPR/Cas12a with a dual amplification strategy for the ultrasensitive monitoring of pesticides such as ACE.

20.
Dalton Trans ; 52(15): 4891-4899, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36943280

RESUMO

Electrocatalyst design is an important approach to prompt the commercialization of water electrolysis technologies. In this work, a ruthenium doped MoS2/AB heterostructure is synthesized as an electrocatalyst for the hydrogen evolution reaction (HER) through hydrothermal and annealing processes. The physical-chemical characterization studies show that the MoS2/AB heterostructure and the incorporation of Ru effectively induce a phase transition from 2H to 1T-MoS2. The as-prepared Ru-MoS2/AB exhibits an excellent HER performance with a very low overpotential of 13 mV at 10 mA cm-2 and a Tafel slope of 31 mV dec-1 in 0.5 M H2SO4, remarkably higher than those of Pt/C (overpotential of 28 mV at 10 mA cm-2, 41 mV dec-1). Density functional theory calculations suggest that the H absorption on Ru bonding to S exhibits a rather low binding energy (-0.22 eV), indicating the optimum active sites of Ru near S for HER. Significantly, the Ru-MoS2/AB also demonstrates high stability under long-term discharge and elevated temperature conditions. These results suggest that the as-prepared Ru-MoS2/AB can be a promising alternative to Pt/C for water electrolysis, due to its high HER activity, easy synthesis, and good stability.

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