RESUMEN
In this study, the chromophore 3,4,9,10-perylenetetracarboxylic diimide (PDI) is anchored with phenyl substituents at the imide N site, followed by thionation, yielding a series of thione products 1S-PDI-D, 2S-cis-PDI-D, 2S-trans-PDI-D, 3S-PDI-D, and 4S-PDI-D, respectively, with n = 1, 2, 3, and 4 thione. The photophysical properties are dependent on the number of anchored thiones, where the observed prominent lower-lying absorption is assigned to the S0 â S2(ππ*) transition and is red-shifted upon increasing the number of thiones; the lowest-lying excited state is ascribed to a transition-forbidden S1(nπ*) configuration. All nS-PDIs are non-emissive in solution but reveal an excellent two-photon absorption cross-section of >800 GM. Supported by the femtosecond transient absorption study, the S1(nπ*) â T1(ππ*) intersystem crossing (ISC) rate is > 1012 s-1, resulting in â¼100% triplet population. The lowest-lying T1(ππ*) energy is calculated to be in the order of 1S-PDI-D > 2S-cis-PDI-D â¼ 2S-trans-PDI-D > 3S-PDI-D > 4S-PDI-D, where the T1 energy of 1S-PDI-D (1.10 eV) is higher than that (0.97 eV) of the 1O2 1Δg state. 1S-PDI-D is further modified by either conjugation with peptide FC131 on the two terminal sides, forming 1S-FC131, or linkage with peptide FC131 and cyanine5 dye on each terminal, yielding Cy5-1S-FC131. In vitro experiments show power of 1S-FC131 and Cy5-1S-FC131 in recognizing A549 cells out of other three lung normal cells and effective photodynamic therapy. In vivo, both molecular composites demonstrate outstanding antitumor ability in A549 xenografted tumor mice, where Cy5-1S-FC131 shows superiority of simultaneous fluorescence tracking and targeted photodynamic therapy.
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Perileno , Fotoquimioterapia , Animales , Carbocianinas , Imidas/química , Ratones , Perileno/química , Perileno/farmacología , TionasRESUMEN
Apolipoprotein E containing high-density lipoprotein (apoE-HDL) and apoE-HDL cholesterol (apoE-HDL-C) are recently recognized as potential biomarkers for coronary heart disease (CHD). We herein developed a two-stage, enzyme-assisted, dual-signal aptasensor that enables a useful electrochemical sensing platform for simultaneous determination of apoE-HDL, apoE-HDL-C, and total HDL-C presented in the sample. The detection scheme consists of two subsystems. In subsystem (I), the level of apoE-HDL is evaluated upon the binding of apoE-specific aptamer and subsequently methylene blue (MB)-labeled DNA displacement occurs on the electrode surface, resulting in electrochemical reduction of methylene blue. In subsystem (II), two kinds of cholesterol levels (apoE-HDL-C and total HDL-C) can be measured. For apoE-HDL-C, the amount of cholesterol in apoE-HDL captured by the aptamer in the first step can be further determined with the aid of surfactant, cholesterol esterase, cholesterol oxidase, and p-aminophenol-mediated electrochemical signal amplification. As for total HDL-C, the amount of cholesterol is determined by the same approach as that used for apoE-HDL-C determination, but without washing (separation). The linear dynamic range for apoE-HDL determination is from 1 to 100 mg/dL (R2 = 1.00). For cholesterol standards, the linear dynamic range is determined to be 0-250 mg/dL (R2 = 0.98). Finally, serial dilutions of purified human HDL preparations were examined using the newly developed aptasensor; the percentage of apoE-HDL-C to HDL-C was found to be ~10%, which correlated well with previously reported values. In conclusion, we successfully developed an electrochemical aptasensor that allows concurrent quantification of apoE-HDL, apoE-HDL-C, and HDL-C on the same platform, offering an efficient, convenient, and purification-free sensing strategy for predictive CHD biomarkers.
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Apolipoproteínas E , HDL-Colesterol , Enfermedad Coronaria , Factores de Riesgo de Enfermedad Cardiaca , Enfermedad Coronaria/diagnóstico , Humanos , Azul de MetilenoRESUMEN
Triplex DNA nanostructures are one of the most emerging and fascinating self-assembled nanostructures due to their unique nanoparticle-like organization and inherit characteristics. They have attracted numerous interests recently because of their versatile and powerful utility in diverse areas of science and technology, such as clinical or disease diagnosis and stimuli-based drug delivery. This review addresses particularly the utilization of DNA triplexes in the development of biosensors for detecting nucleic acid; strategies in sensing pH, protein activity, ions, or molecules. Finally, an outlook for potential applications of triplex DNA nanoswitches is provided.
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Técnicas Biosensibles , Nanoestructuras , ADN/química , Nanoestructuras/química , Conformación de Ácido NucleicoRESUMEN
Cytomegalovirus (CMV) is the most frequent cause of congenital infection worldwide; congenital CMV may lead to significant mortality, morbidity, or long-term sequelae, such as sensorineural hearing loss. The current study presents a newly designed surface plasmon resonance (SPR) biosensor for CMV-specific microRNAs that does not involve extra care for receptor immobilization or treatment to prevent fouling on bare gold surfaces. The modification-free approach, which utilizes a poly-adenine [poly(A)]-Au interaction, exhibited a high affinity that was comparable to that of the gold-sulfur (Au-S) interaction. In addition, magnetic nanoparticles (MNPs) were used to separate the analyte from complex sample matrixes that significantly reduced nonspecific adsorption. Moreover, the MNPs also played an important role in SPR signal amplification due to the binding-induced change in the refractive index. Our SPR biosensing platform was used successfully for the multi-detection of the microRNAs, UL22A-5p, and UL112-3p, which were associated with CMV. Our SPR biosensor offered the detection limits of 108 fM and 24 fM for UL22A-5p and UL112-3p, respectively, with an R2 of 0.9661 and 0.9985, respectively. The precision of this biosensor has an acceptable CV (coefficient of variation) value of <10%. In addition, our sensor is capable of discriminating between serum samples collected from healthy and CMV-infected newborns. Taken together, we believe that our newly developed SPR biosensing platform is a promising alternative for the diagnosis of CMV-specific microRNA in clinical settings, and its application for the detection of other miRNAs may be extended further.
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Técnicas Biosensibles , Nanopartículas del Metal , MicroARNs , Citomegalovirus/genética , Oro , Humanos , Recién Nacido , MicroARNs/genética , Resonancia por Plasmón de SuperficieRESUMEN
BACKGROUND: Areas of hypoxia are often found in triple-negative breast cancer (TNBC), it is thus more difficult to treat than other types of breast cancer, and may require combination therapies. A new strategy that combined bioreductive therapy with photodynamic therapy (PDT) was developed herein to improve the efficacy of cancer treatment. Our design utilized the characteristics of protoporphyrin IX (PpIX) molecules that reacted and consumed O2 at the tumor site, which led to the production of cytotoxic reactive oxygen species (ROS). The low microenvironmental oxygen levels enabled activation of a bioreductive prodrug, tirapazamine (TPZ), to become a toxic radical. The TPZ radical not only eradicated hypoxic tumor cells, but it also promoted therapeutic efficacy of PDT. RESULTS: To achieve the co-delivery of PpIX and TPZ for advanced breast cancer therapy, thin-shell hollow mesoporous Ia3d silica nanoparticles, designated as MMT-2, was employed herein. This nanocarrier designed to target the human breast cancer cell MDA-MB-231 was functionalized with PpIX and DNA aptamer (LXL-1), and loaded with TPZ, resulting in the formation of TPZ@LXL-1-PpIX-MMT-2 nanoVector. A series of studies confirmed that our nanoVectors (TPZ@LXL-1-PpIX-MMT-2) facilitated in vitro and in vivo targeting, and significantly reduced tumor volume in a xenograft mouse model. Histological analysis also revealed that this nanoVector killed tumor cells in hypoxic regions efficiently. CONCLUSIONS: Taken together, the synergism and efficacy of this new therapeutic design was confirmed. Therefore, we concluded that this new therapeutic strategy, which exploited a complementary combination of PpIX and TPZ, functioned well in both normoxia and hypoxia, and is a promising medical procedure for effective treatment of TNBC.
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Antineoplásicos/farmacología , Nanopartículas/uso terapéutico , Fotoquimioterapia/métodos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Aptámeros de Nucleótidos , Línea Celular Tumoral , Terapia Combinada , Femenino , Humanos , Ratones , Oxígeno , Profármacos , Especies Reactivas de Oxígeno , Dióxido de Silicio , Tirapazamina , Carga Tumoral , Hipoxia Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
DNA nanotechnology provides powerful tools for developing cancer theranostics. Here we introduce the autonomous surface-nucleolin-guided HCR that leads to the polymerization of G-quadruplex polymer chains, in which the ZnII -protoporphyrin IX is intercalated. We demonstrate that MDA-MB-231 (Triple Negative Breast Cancer cells, TNBC) with overexpressed surface nucleolin were able to induce HCR leading to the formation of the ZnII PPIX-loaded G-quadruplex polymer chains, while the M10 epithelial breast cells served as control. The ZnII PPIX-loaded nanowires allow the selective imaging of TNBC, and their permeation into the TNBC leads to selective cytotoxicity and guided photodynamic therapy toward the cancer cells due to structural perturbation of the membranes. The aptamer-guided HCR-generated G-quadruplex polymer chains may serve as a versatile tool to target TNBC featuring poor prognosis and high pathological risk of recurrence, thus offering a promising theranostic platform.
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Antineoplásicos/farmacología , Aptámeros de Nucleótidos/farmacología , Complejos de Coordinación/farmacología , Protoporfirinas/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Zinc/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Aptámeros de Nucleótidos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Ensayos de Selección de Medicamentos Antitumorales , G-Cuádruplex , Humanos , Hibridación de Ácido Nucleico , Protoporfirinas/química , Neoplasias de la Mama Triple Negativas/patología , Zinc/químicaRESUMEN
Lung cancer is the primary cause of cancer-associated mortality worldwide, which makes the identification of reliable lung cancer biomarkers a pressing need for early diagnosis and prognosis. RGS11, which is a regulator of G-protein signaling and also a lung cancer biomarker, plays an important role in cancer-related metastasis. However, trace levels of RGS11 (in the range of pg/mL) in serum samples make it difficult to quantify using currently available enzyme-linked immunosorbent assay (ELISA) kits and, therefore, this hinders progress in the discovery of new approaches for treating lung cancer. The aim of this study is to develop a rapid, sensitive, and reliable platform for the detection of RGS11 lung cancer biomarker based on a suspension immunoassay coupled with an isothermal exponential amplification strategy. Our study was initiated by the functionalization of magnetic beads with anti-RGS11 antibodies (Ab-MB) by EDC (1-ethyl-3-(3-(dimethylamino)propyl)-carbodiimide)/NHS ( N-hydroxysulfosuccinimide) activation. Ab-MB served as a sensing probe for the competitive immunorecognitions between known concentrations of His-tag RGS11 and unknown concentrations of target RGS11 in serum. The reporter anti-His antibodies, which were modified with primers that induced an isothermal exponential amplification reaction, were subsequently introduced to the reaction mixture that resulted in the formation of immunosandwich complexes. The exponentially amplified DNA duplex that was intercalated with SYBR Green was designated as a signal reporter for the assessment of RGS11 in an inversely proportional relationship. The sensing platform was excellent for the determination of RGS11 with an exceptional detection limit of 148 fg/mL and a linear dynamic range of 0.1-10 pg/mL using a minimal sample volume (20 µL) and with a reaction time of 1.5 h. In addition, we challenged the sensing platform with RGS11-spiked samples (in 2× diluted serum), and an acceptable recovery rate (>90%) was observed. Finally, 24 clinical samples acquired from patients with advanced lung cancer (C), inflammation (I), and heart failure (H) were analyzed by this newly developed sensing platform and a commercial ELISA kit for validation. This sensing platform has potential in biomedical applications for clinically diagnosing liquid biopsy samples for patients with lung cancer. Moreover, the universal design of our proposed system is easily adapted to detect any other protein if a His-tag recombinant protein is available.
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Biomarcadores de Tumor/sangre , Inmunoensayo/métodos , Neoplasias Pulmonares/diagnóstico , Proteínas RGS/sangre , Anticuerpos Inmovilizados/química , Anticuerpos Inmovilizados/inmunología , Reacciones Antígeno-Anticuerpo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/inmunología , Histidina/genética , Histidina/inmunología , Histidina/metabolismo , Humanos , Límite de Detección , Neoplasias Pulmonares/metabolismo , Magnetismo , Técnicas de Amplificación de Ácido Nucleico , Oligopéptidos/genética , Oligopéptidos/inmunología , Oligopéptidos/metabolismo , Proteínas RGS/genética , Proteínas RGS/inmunologíaRESUMEN
We developed a simple, sensitive inner filter effect (IFE)-based fluorescent assay for sensing H2O2 and cholesterol. In the process, poly(vinylpyrrolidone)-protected gold nanoparticles (PVP-AuNPs) and fluorescent BSA-protected gold nanoclusters (BSA-AuNCs) were used as an IFE absorber/fluorophore pair. PVP-AuNPs can be a powerful absorber to influence the emission of the fluorophore, BSA-AuNCs, in the IFE-based fluorescent assays. That is due to the high extinction coefficient of AuNPs and the complementary overlap between the surface plasmon resonance (SPR) absorption of PVP-AuNPs and the excitation of BSA-AuNCs. The PVP-Au seeds, produced by directly mixing PVP with HAuCl4, were able to catalyze H2O2 to enlarge AuNPs. The SPR absorption of PVP-AuNPs was enhanced with an increased concentration of H2O2 and, subsequently, induced significant fluorescence quenching of BSA-AuNCs. The IFE-based fluorescent assay enabled the detection of H2O2 and generation of H2O2 in the presence of O2/cholesterol and cholesterol oxidase (ChOx) by the fluorescence response of BSA-AuNCs. The present IFE-based approach can detect H2O2 ranging from 1 to 100 µM with a detection limit of 0.8 µM and cholesterol ranging from 1 to 100 µM with a detection limit of 1.4 µM.
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Colesterol/análisis , Fluorescencia , Oro/química , Peróxido de Hidrógeno/análisis , Nanopartículas del Metal/química , Animales , Bovinos , Albúmina Sérica Bovina/química , Espectrometría de FluorescenciaRESUMEN
An optically active polyaniline nanomaterial (PANI-Nap), doped with (S)-naproxen, was developed and evaluated as a potent pH sensor. We synthesized the material in one pot by the addition of the dopant, (S)-naproxen, prior to polymerization, followed by the addition of the oxidizing agent (ammonium persulfate) that causes polymerization of the aniline. This green chemistry approach allowed us to take only 1 h to produce a water-soluble and stable nanomaterial. UV-visible spectroscopy, fluorescence spectroscopy, FT-IR spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the designed nanomaterial. This nanomaterial exhibited excellent pH sensing properties and showed long term stability (up to one month) without loss of sensor performance.
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Compuestos de Anilina/química , Tecnología Química Verde , Nanofibras/química , Naproxeno/química , Sulfato de Amonio/química , Concentración de Iones de Hidrógeno , Nanofibras/ultraestructura , Oxidantes/química , Polimerizacion , Solubilidad , Soluciones , Agua/químicaRESUMEN
Aging, marked by dysregulated cellular systems, gives rise to a spectrum of age-related disorders, including neurodegeneration, atherosclerosis, immunosenescence, and musculoskeletal issues. These conditions contribute significantly to the global disease burden, posing challenges to health span and economic resources. Current therapeutic approaches, although diverse in mechanism, often fall short in targeting the underlying cellular pathologies. They fail to address the issues compounded by altered pharmacokinetics in the elderly. Nanotechnology emerges as a transformative solution, offering tissue-specific targeted therapies through nanoparticles. Functional nanomaterials (FNMs) respond to internal or external stimuli, with light-responsive nanomaterials gaining prominence. Harnessing the benefits of deep tissue penetration and ease of manipulation particularly in the near-infrared spectrum, light-responsive FNMs present innovative strategies for age-related comorbidities. This review comprehensively summarizes the potential of light-responsive FNM-based approaches for targeting cellular environments in age-related disorders, and also emphasizes the advantages over traditional treatment modalities. Specifically, it focuses on the development of various classes of light-responsive functional nanomaterials including plasmonic nanomaterials, nanomaterials as carriers, upconversion nanomaterials, 2D nanomaterials, transition metal oxide and dichalcogenide nanomaterials and carbon-based nanomaterials against age related diseases. We foresee that such advanced developments in the field of nanotechnology could provide a new hope for clinical diagnosis and treatment of age-related disorders.
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Nanoestructuras , Humanos , Nanoestructuras/química , Envejecimiento/efectos de los fármacos , Animales , LuzRESUMEN
Due to its physiologic role in modulating adhesive interactions between blood cells and the endothelium during inflammatory processes or at injury sites, the adhesion molecule P-selectin is of great interest. The level of soluble P-selectin in plasma or serum can be detected and used as a clinical predictor for adverse cardiovascular events, leading to the presumption that it is secreted, shed or cleaved from the cell membrane during the process of diseases. Increased levels of soluble P-selectin in the plasma have been shown to be associated with a range of cardiovascular disorders, including coronary artery disease, hypertension and atrial fibrillation. Therefore, it is of huge significance to develop simple, rapid and sensitive methods for the detection of such pathological predictors, not only for facilitating the surveillance of cardiovascular mortality/sudden cardiac death, but also for effectively monitoring the drug potency on platelets based on measurement of P-selectin performed on fixed blood samples following platelet stimulation in whole blood in a remote setting. We herein developed a simple, yet novel and sensitive electrochemical sandwich immunosensor for the detection of P-selectin; it operates through covalent linkage of anti-P-selectin antibody on CNT@GNB nanocomposites-modified disposable screen-printed electrode as the detection platform, with the potassium ferrocyanide-encapsulated, anti-P-selectin-tagged liposomal biolabels as the electrochemical signal probes. The immunorecognition of the sample P-selectin by the liposomal biolabels occurred on the surface of the electrodes; the release of potassium ferrocyanide from the bound liposomal biolabels extensively contributed to the increase in electrochemical signal, which was acquired in HCl solution at +0.32V in square wave voltammetry mode. The resulting sigmoidally shaped dose-response curves possessed a linear dynamic working range from 1×10(-13) to 1×10(-5)g/mL. This liposome-based electrochemical immunoassay provides an amplification approach for detecting P-selectin at trace levels, leading to a detection limit as low as 4.3fg (equivalent to 5µL of 0.85pg/mL solution). A commercially available ELISA kit was used as a reference method to validate the newly-developed assay through the analysis of mouse serum samples. A strong correlation was observed between the two data sets as the R-squared value of 0.997 from the linear regression line. This electrochemical immunosensor will be useful for the detection of P-selectin in biological fluids and tissue extracts.
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Técnicas Biosensibles/instrumentación , Enfermedades Cardiovasculares/diagnóstico , Inmunoensayo/instrumentación , Selectina-P/sangre , Animales , Biomarcadores/sangre , Biomarcadores/química , Técnicas Biosensibles/métodos , Enfermedades Cardiovasculares/inmunología , Membrana Celular/química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Ensayo de Inmunoadsorción Enzimática , Ferrocianuros/química , Ácido Clorhídrico/química , Inmunoensayo/métodos , Límite de Detección , Modelos Lineales , Liposomas/química , Ratones , Nanocompuestos/química , Reproducibilidad de los Resultados , Factores de Riesgo , Solubilidad , Factores de TiempoRESUMEN
The characteristics of global prevalence and high recurrence of bladder cancer has led numerous efforts to develop new treatments. The spontaneous voiding and degradation of the chemodrug hamper the efficacy and effectiveness of intravesical chemotherapy following tumor resection. Herein, the externally thiolated hollow mesoporous silica nanoparticles (MSN-SH(E)) is fabricated to serve as a platform for improved bladder intravesical therapy. Enhanced mucoadhesive effect of the thiolated nanovector is confirmed with porcine bladder. The permeation-enhancing effect is also verified, and a fragmented distribution pattern of a tight junction protein, claudin-4, indicates the opening of tight junction. Moreover, MSN-SH(E)-associated reprogramming of M2 macrophages to M1-like phenotype is observed in vitro. The antitumor activity of the mitomycin C (MMC)-loaded nanovector (MMC@MSN-SH(E)) is more effective than that of MMC alone in both in vitro and in vivo. In addition, IHC staining is used to analyze IFN-γ, TGF-ß1, and TNF-α. These observations substantiated the significance of MMC@MSN-SH(E) in promoting anticancer activity, holding the great potential for being used in intravesical therapy for non-muscle invasive bladder cancer (NMIBC) due to its mucoadhesivity, enhanced permeation, immunomodulation, and prolonged and very efficient drug exposure.
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Nanopartículas , Neoplasias de la Vejiga Urinaria , Animales , Porcinos , Antibióticos Antineoplásicos , Adyuvantes Inmunológicos/uso terapéutico , Dióxido de Silicio , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Mitomicina/uso terapéuticoRESUMEN
The telomerase-specific oncolytic adenovirus Telomelysin and the histone deacetylase inhibitor AR42 have demonstrated anticancer effects in preclinical models of human hepatocellular carcinoma (HCC). However, the clinical development of Telomelysin may be hindered by human antiviral immunity and tumor resistance. Combining oncolytic and epigenetic therapies is a viable approach for treating various cancers. This study investigated the potential synergism of Telomelysin and AR42 and the relevant underlying mechanisms. Telomelysin and AR42 exhibited synergistic antiproliferative effects in human HCC models in vitro and in vivo. Apoptosis induced by Telomelysin was significantly enhanced by AR42 in both PLC5 and Hep3B HCC cells. AR42 treatment unexpectedly attenuated the expression of the coxsackievirus and adenovirus receptor and the mRNA levels of human telomerase reverse transcriptase, which may be positively associated with the cytotoxicity of Telomelysin. Meanwhile, the cellular antiviral interferon response was not altered by AR42 treatment. Further, we found that Telomelysin enhanced Akt phosphorylation in HCC cells. AR42 reduced Telomelysin-induced phospho-Akt activation and enhanced Telomelysin-induced apoptosis. The correlation of Akt phosphorylation with drug-induced apoptosis was validated in HCC cells with upregulated or downregulated Akt signaling. Combination therapy with Telomelysin and AR42 demonstrated synergistic anti-HCC efficacy. Clinical trials investigating this new combination regimen are warranted.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Viroterapia Oncolítica , Telomerasa , Humanos , Carcinoma Hepatocelular/terapia , Telomerasa/genética , Telomerasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Histona Desacetilasas/metabolismo , Línea Celular Tumoral , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Adenoviridae/genética , ApoptosisRESUMEN
Rationale: Prediabetes can be reversed through lifestyle intervention, but its main pathologic hallmark, insulin resistance (IR), cannot be detected as conveniently as blood glucose testing. In consequence, the diagnosis of prediabetes is often delayed until patients have hyperglycemia. Therefore, developing a less invasive diagnostic method for rapid IR evaluation will contribute to the prognosis of prediabetes. Adipose tissue is an endocrine organ that plays a crucial role in the development and progression of prediabetes. Label-free visualizing the prediabetic microenvironment of adipose tissues provides a less invasive alternative for the characterization of IR and inflammatory pathology. Methods: Here, we successfully identified the differentiable features of prediabetic adipose tissues by employing the metabolic imaging of three endogenous fluorophores NAD(P)H, FAD, and lipofuscin-like pigments. Results: We discovered that 1040-nm excited lipofuscin-like autofluorescence could mark the location of macrophages. This unique feature helps separate the metabolic fluorescence signals of macrophages from those of adipocytes. In prediabetes fat tissues with IR, we found only adipocytes exhibited a low redox ratio of metabolic fluorescence and high free NAD(P)H fraction a1. This differential signature disappears for mice who quit the high-fat diet or high-fat-high-sucrose diet and recover from IR. When mice have diabetic hyperglycemia and inflamed fat tissues, both adipocytes and macrophages possess this kind of metabolic change. As confirmed with RNA-seq analysis and histopathology evidence, the change in adipocyte's metabolic fluorescence could be an indicator or risk factor of prediabetic IR. Conclusion: Our study provides an innovative approach to diagnosing prediabetes, which sheds light on the strategy for diabetes prevention.
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Hiperglucemia , Resistencia a la Insulina , Estado Prediabético , Ratones , Animales , Estado Prediabético/diagnóstico , Estado Prediabético/metabolismo , Lipofuscina/metabolismo , NAD/metabolismo , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/metabolismo , Hiperglucemia/metabolismoRESUMEN
In this paper, we describe a simple one-pot method, employing l-3,4-dihydroxyphenylalanine (L-DOPA) as a reducing/capping reagent, for the synthesis of fluorescent gold nanoclusters (AuNCs). Within a short reaction time of 15 min (excluding the time required for purification), this strategy allows the fabrication of homogeneous AuNCs having the capability to sense ferric ions (Fe(3+)). The as-prepared AuNCs exhibited a fluorescence emission at 525 nm and a quantum yield of 1.7%. On the basis of an aggregation-induced fluorescence quenching mechanism, these fluorescent AuNCs offer acceptable sensitivity, high selectivity, and a limit of detection of 3.5 µM for the determination of Fe(3+) ions, which is lower than the maximum level (0.3 mg L(-1), equivalent to 5.4 µM) of Fe(3+) permitted in drinking water by the U.S. Environmental Protection Agency.
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Técnicas de Química Analítica/instrumentación , Dihidroxifenilalanina/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Oro/química , Hierro/análisis , Nanopartículas del Metal/química , Tampones (Química) , Cloruros/química , Suplementos Dietéticos/análisis , Compuestos de Oro/química , Concentración de Iones de Hidrógeno , Hierro/química , Lagos/química , Límite de Detección , Fenómenos Ópticos , Oxidación-Reducción , Relación Señal-Ruido , Factores de Tiempo , Agua/químicaRESUMEN
The vascular endothelial growth factor, VEGF, is an important biomarker for different diseases and clinical disorders. We present a series of optical aptasensor-based sensing platforms for VEGF that include the following: (i) A FRET-based sensor that involves the VEGF-induced separation of aptamer-functionalized quantum dots blocked by a quencher nucleic acid (detection limit 1 nM). (ii) A FRET-based sensor based on the VEGF-induced assembly of the aptamer subunits functionalized with QDs and a dye acceptor (Cy5), respectively (detection limit 12 nM). (iii) A chemiluminescence aptasensor based on VEGF-induced assembly of a hemin/G-quadruplex catalyst (detection limit 18 nM). (iv) A chemiluminescence aptasensor based on the VEGF-stimulated assembly of two aptamer subunits into the hemin/G-quadruplex catalyst (detection limit 2.6 nM). (v) A chemiluminescence resonance energy transfer (CRET) aptasensor based on the VEGF-induced assembly of a semiconductor QDs-hemin/G-quadruplex supramolecular structure (detection limit 875 pM). Furthermore, an amplified optical aptasensor system based on the Exonuclease III (Exo III) recycling of the VEGF analyte was developed. In this system, one aptamer subunit is modified at its 5' and 3' ends with QDs and a black hole quencher, respectively. The VEGF-induced self-assembly of the aptamer subunits result in the digestion of the quencher units and the autonomous recycling of the analyte, while triggering-on the luminescence of the QDs (detection limit 5 pM). The system was implemented to analyze VEGF in human sera samples.
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Aptámeros de Nucleótidos/metabolismo , Técnicas Biosensibles/métodos , Fenómenos Ópticos , Factor A de Crecimiento Endotelial Vascular/análisis , Aptámeros de Nucleótidos/genética , Secuencia de Bases , Exodesoxirribonucleasas/metabolismo , Transferencia Resonante de Energía de Fluorescencia , G-Cuádruplex , Hemina/metabolismo , Humanos , Mediciones Luminiscentes , Puntos Cuánticos , Factor A de Crecimiento Endotelial Vascular/sangreRESUMEN
Bottom-up approaches in creating artificial cells that can mimic natural cells have significant implications for both basic research and translational application. Among various artificial cell models, liposome is one of the most sophisticated systems. By encapsulating proteins and associated biomolecules, they can functionally reconstitute foundational features of biological cells, such as the ability to divide, communicate, and undergo shape deformation. Yet constructing liposome artificial cells from the genetic level, which is central to generate self-sustained systems remains highly challenging. Indeed, many studies have successfully established the expression of gene-coded proteins inside liposomes. Further, recent endeavors to build a direct integration of gene-expressed proteins for reconstituting molecular functions and phenotypes in liposomes have also significantly increased. Thus, this review presents the development of liposome-based artificial cells to demonstrate the process of gene-expressed proteins and their reconstitution to perform desired molecular and cell-like functions. The molecular and cellular phenotypes discussed here include the self-production of membrane phospholipids, division, shape deformation, self-DNA/RNA replication, fusion, and intercellular communication. Together, this review gives a comprehensive overview of gene-expressing liposomes that can stimulate further research of this technology and achieve artificial cells with superior properties in the future.
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Células Artificiales , Células Artificiales/metabolismo , Liposomas/metabolismo , Proteínas/genética , Fenotipo , Expresión GénicaRESUMEN
Using in vivo multiphoton fluorescent dosimetry, we demonstrate that the clearance dynamics of Indocyanine Green (ICG) in the blood can quickly reveal liver function reserve. In normal rats, the ICG retention rate was below 10% at the 15-minute post-administration; While in the rat with severe hepatocellular carcinoma (HCC), the 15-minute retention rate is over 40% due to poor liver metabolism. With a 785 nm CW laser, the fluorescence dosimeter can evaluate the liver function reserve at a 1/10 clinical dosage of ICG without any blood sampling. In the future, this low-dosage ICG 15-minute retention dosimetry can be applied for the preoperative assessment of hepatectomy or timely perioperative examination.
RESUMEN
Measuring the kinetic constants of protein-protein interactions at ultralow concentrations becomes critical in characterizing biospecific affinity, and exploring the feasibility of clinical diagnosis with respect to detection sensitivity, efficiency and accuracy. In this study, we propose a method that can calculate the binding constants of protein-protein interactions in sandwich assays at ultralow concentrations at the pg/mL level, using a localized surface plasmon coupled fluorescence fiber-optic biosensor (LSPCF-FOB). We discuss a two-compartment model to achieve reaction-limited kinetics under the stagnant conditions of the reaction chamber. The association rate constant, dissociation rate constant, and the equilibrium dissociation constant, that is, k(a), k(d), K(D), respectively, of the kinetics of binding between total prostate-specific antigen (t-PSA) and anti-t-PSA at concentrations from 0.1 pg/mL to 1 ng/mL, were measured either in PBS or in human serum. This is the first time that k(a), k(d), and K(D) have been measured at such a low concentration range in a complex sample such as human serum.
Asunto(s)
Técnicas Biosensibles/métodos , Oro/química , Nanopartículas del Metal/química , Animales , Anticuerpos Inmovilizados/inmunología , Técnicas Biosensibles/instrumentación , Bovinos , Humanos , Inmunoglobulina G/inmunología , Cinética , Límite de Detección , Ratones , Fibras Ópticas , Unión Proteica , Espectrometría de Fluorescencia , Especificidad por SustratoRESUMEN
In this study, we have successfully developed a facile method for the high-yield fabrication of Au-Pd core-shell heterostructures with an unusual tetrahexahedral (THH) morphology using Au nanocubes as the structure-directing cores. The lattice orientations of the Au nanocubes match those of the Pd shells. Structural analysis establishes that the THH nanocrystals are bounded by high-index {730} facets. A substantial lattice mismatch between Au and Pd, oxidative etching in the presence of chloride and oxygen, the use of cetyltrimethylammonium chloride (CTAC) surfactant, and the reaction temperature (30-60 °C) were identified to be key factors facilitating the formation of the THH core-shell nanocrystals. Intermediate products have also been examined to follow the growth process. By selecting cubic gold cores with sizes of 30-70 nm and varying the volume of the gold core solution used, THH Au-Pd core-shell nanocrystals with continuously adjustable sizes from 56 to 124 nm can be readily obtained. Their UV-vis spectra display progressive red-shifted bands. Interestingly, novel concave octahedral and octahedral Au-Pd core-shell nanocrystals can be prepared by lowering the reaction temperature and prolonging the reaction time. The concave octahedra show depressions on all the {111} faces. Electrocatalytic activity of the three Au-Pd core-shell structures for the oxidation of ethanol has been investigated. The THH nanocrystals with entirely high-index {730} facets were found to exhibit the best electrocatalytic activity. These size-tunable THH Au-Pd core-shell nanocrystals may be valuable for catalyzing other organic reactions.