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1.
Pharmacol Res ; 208: 107355, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39179052

RESUMO

The activating transcription factor (ATF)/ cAMP-response element binding protein (CREB) family represents a large group of basic zone leucine zip (bZIP) transcription factors (TFs) with a variety of physiological functions, such as endoplasmic reticulum (ER) stress, amino acid stress, heat stress, oxidative stress, integrated stress response (ISR) and thus inducing cell survival or apoptosis. Interestingly, ATF family has been increasingly implicated in autophagy and ferroptosis in recent years. Thus, the ATF family is important for homeostasis and its dysregulation may promote disease progression including cancer. Current therapeutic approaches to modulate the ATF family include direct modulators, upstream modulators, post-translational modifications (PTMs) modulators. This review summarizes the structural domain and the PTMs feature of the ATF/CREB family and comprehensively explores the molecular regulatory mechanisms. On this basis, their pathways affecting proliferation, metastasis, and drug resistance in various types of cancer cells are sorted out and discussed. We then systematically summarize the status of the therapeutic applications of existing ATF family modulators and finally look forward to the future prospect of clinical applications in the treatment of tumors by modulating the ATF family.


Assuntos
Fatores Ativadores da Transcrição , Antineoplásicos , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/genética , Animais , Fatores Ativadores da Transcrição/metabolismo , Fatores Ativadores da Transcrição/genética , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos
2.
ACS Sens ; 9(8): 4098-4106, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39033535

RESUMO

Nucleic acid detection plays a crucial role in various aspects of health care, necessitating accessible and reliable quantification methods, especially in resource-limited settings. This work presents a simplified electrochemical approach for end-point yet quantitative nucleic acid detection. By elevating the concentration of redox species and choosing potential as the signals, we achieved enhanced signal robustness, even in the presence of interfering substances. Leveraging this robustness, we accurately measured pH-induced redox potential changes in methylene blue solution for end-point nucleic acid detection after loop-mediated isothermal amplification (LAMP). Our method demonstrated quantitative detection of the SARS-CoV-2 N gene and human ATCB gene and successful discrimination of the human BRAF V600E mutation, comparable in sensitivity to commercial kits. The developed user-friendly electrochemical method offers a simplified and reliable approach for end-point yet quantitative detection of nucleic acids, potentially expanding the benefits of nucleic acid testing in resource-limited settings.


Assuntos
Técnicas Eletroquímicas , Técnicas de Amplificação de Ácido Nucleico , SARS-CoV-2 , Técnicas Eletroquímicas/métodos , Humanos , SARS-CoV-2/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Proteínas Proto-Oncogênicas B-raf/genética , COVID-19/diagnóstico , COVID-19/virologia , Azul de Metileno/química , Mutação , Oxirredução , Técnicas de Diagnóstico Molecular/métodos , Região de Recursos Limitados
3.
Chem Commun (Camb) ; 60(15): 2034-2037, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38284796

RESUMO

The CRISPR/Cas12a system is accelerated by glutathione-mediated reduction of MnO2 nanosheets. By monitoring the trans-cleavage of the DNA probe, an electrochemical method for glutathione assay is fabricated, with the detection limit of 3.5 pM. It provides a promising tool for plasma analysis with satisfactory performance, indicating the broad application prospects of this glutathione assay.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , Óxidos , Compostos de Manganês , Glutationa/análise
4.
ACS Appl Bio Mater ; 6(8): 3084-3088, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37565741

RESUMO

Green-emissive carbon nanodots (CDs) with high quantum yield are prepared. The abundant functional groups on the surfaces of CDs can selectively interact with Cu2+. The formed cupric amine complexes induce significant fluorescence quenching. The "on-off" switching can be further adjusted to the fluorescence "on" mode by the introduction of glutathione (GSH), which hinders the interactions between CDs and Cu2+. Based on the fantastic optical behavior of CDs, highly sensitive detection of Cu2+ and GSH can be achieved. Intracellular imaging of the two targets is also validated.


Assuntos
Carbono , Glutationa , Espectrometria de Fluorescência/métodos
5.
Colloids Surf B Biointerfaces ; 229: 113482, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37523806

RESUMO

The concentration of circulating tumor cells (CTCs) in peripheral blood is strongly correlated with the progress of certain metastatic cancers. In this study, we have developed a novel and facile electrochemical biosensor for the detection of CTCs based on the use of manganese dioxide nanosheets (MnO2 NSs) and gold nanoparticles (AuNPs). Aptamer sequence of target cell is modified on the surface of AuNPs for specifical recognition. With low-speed centrifugation, numerous AuNPs@DNA can be removed from the supernatant. On the other hand, MnO2 NSs are modified on the electrode surface to capture unreacted AuNPs@DNA. The declined electrochemical signal intensity can be used to reflect the level of CTCs. This biosensor achieves a wide linear range from 10 to 104 cells mL-1 and a limit of detection as low as 3 cells mL-1. Due to the specific aptamer as the recognition element, interfering cells can be successfully distinguished and this method performs satisfactorily in clinical samples. Therefore, it has great potential to be used as a powerful tool benefiting rare cells analysis and the investigation of dynamics of cellular interactions.


Assuntos
Técnicas Biossensoriais , Ouro , Compostos de Manganês , Nanopartículas Metálicas , Células Neoplásicas Circulantes , Óxidos , Humanos , Técnicas Eletroquímicas , Comunicação Celular
6.
Front Oncol ; 13: 1144047, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37274262

RESUMO

Objective: For elderly patients aged ≥75 with esophageal cancer, whether surgical treatment is safe and effective and whether it is feasible to use a relatively radical "no tube, no fasting" fast-track recovery protocol remain topics of debate. We conducted a retrospective analysis to shed light on these two questions. Methods: We retrospectively collected the data of patients who underwent McKeown minimally invasive esophagectomy (MIE) combined with early oral feeding (EOF) on postoperative day 1 between April 2015 and December 2017 at Medical Group 1, Ward 1, Department of Thoracic Surgery of our hospital. Preoperative characteristics, postoperative complications, operation time, intraoperative blood loss, duration of anastomotic leakage (day), hospital stay, and survival were evaluated. Results: Twenty-three elderly patients with esophageal cancer underwent surgery with EOF. No significant difference was observed in intraoperative measures. The incidence of postoperative complications was 34.8% (8/23). Two patients (8.7%) were terminated early during the analysis of the feasibility of EOF. For all 23 patients, the mean hospital stay was 11.4 (5-42) days, and the median survival was 51 months. Conclusion: Patients aged ≥75 with resectable esophageal cancer can achieve long-term survival with active surgical treatment. Moreover, the "no tube, no fasting" fast-track recovery protocol is safe and feasible for elderly patients.

7.
Drug Des Devel Ther ; 17: 1665-1677, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37309414

RESUMO

Objective: To investigate the feasibility of multimodal regimen by paracetamol, gabapentin, ketamine, lidocaine, dexmedetomidine and sufentanil among cardiac surgery patients, and compare the analgesia efficacy with conventional sufentanil-based regimen. Design: A single-center, prospective, randomized, controlled clinical trial. Setting: One participating center, the cardiovascular center of the major integrated teaching hospital. Participants: A total of 115 patients were assessed for eligibility: 108 patients were randomized, 7 cases were excluded. Interventions: The control group (group T) received conventional anesthesia management. Interventions in the multimodal group (group M) were as follows in addition to the standard of care: gabapentin and acetaminophen 1 hour before surgery; ketamine for induction and to maintain anesthesia with lidocaine and dexmedetomide. Ketamine, lidocaine, and dexmedetomidine were added to routine sedatives postoperatively in group M. Measurements and Main Results: The incidence of moderate-to-severe pain on coughing made no significant difference (68.5% vs 64.8%, P=0.683). Group M had significantly less sufentanil use (135.72µg vs 94.85µg, P=0.000) and lower rescue analgesia rate (31.5% vs 57.4%, P=0.007). There was no significant difference in the incidence of chronic pain, PONV, dizziness, inflammation index, mechanical ventilation time, length of stay, and complications between the two groups. Conclusion: Our multimodal regimen in cardiac surgery is feasible, but was not superior to traditional sufentanil-based regimen in the aspects of analgesia effects; however, it did reduce perioperative opioid consumption along with rescue analgesia rate. Moreover, it showed the same length of stay and the incidences of postoperative complications.


Assuntos
Analgesia , Procedimentos Cirúrgicos Cardíacos , Dor Crônica , Dexmedetomidina , Ketamina , Humanos , Sufentanil , Gabapentina , Estudos Prospectivos , Lidocaína , Acetaminofen
8.
ACS Appl Mater Interfaces ; 15(22): 26241-26251, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37232130

RESUMO

Synergetic photothermal/photodynamic/chemotherapy receives significant attention for precise in vivo cancer treatment. Despite plenty of encouraging photosensitizers explored, integrated nanoagents with multiple functions are still highly desired. In this study, novel nanocomposites coupling black phosphorus (BP) nanosheets, gold nanorods (AuNRs), carbon nanodots (CDs), and doxorubicin (Dox) are prepared. The nanoagents exhibit high antitumor activity on account of their broad light absorption, excellent catalytic ability, and significant photothermal and photodynamic effects. CDs not only emit bright fluorescence for accurate diagnosis and guiding of tumor treatment but also catalyze the generation of ROS for photodynamic therapy (PDT). The released Dox induces apoptosis of cells and increases the levels of H2O2 to promote PDT. AuNRs are the main photothermal therapy (PTT) material that converts light into heat. Moreover, BP can be used to enhance both PTT and PDT efficiencies, and the two therapy modes can be cooperatively reinforced. It is also found that the local immune microenvironment of the tumors is activated. The strategy makes good use of the features of each component. Satisfactory antitumor phenomena are well confirmed by in vitro and in vivo results. This study provides new insights into enhanced synergetic therapy, highlighting the great utility of BP-based nanoagents in the field of nanomedicine.


Assuntos
Nanotubos , Neoplasias , Fotoquimioterapia , Humanos , Carbono/uso terapêutico , Linhagem Celular Tumoral , Ouro/uso terapêutico , Peróxido de Hidrogênio , Neoplasias/tratamento farmacológico , Fósforo/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral
9.
Anal Chem ; 95(23): 8842-8849, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37255274

RESUMO

Biomimetic structures to fabricate bioelectronic interfaces that allow sensors to electrically communicate with electrodes have potential applications in the development of biosensors. Herein, inspired by the structure feature of nitric oxide (NO) sensory protein, we constructed a biomimetically catalytic center, the histamine coordinated iron phthalocyanine (FePc), for efficient and sensitive detection of NO. In specific, NO is recognized by axial tethered FePc, and the oxidative signal of NO on FePc is converted into output signal through electrocatalytic oxidation. Based on the fabricated catalytic structure on the carbon fiber electrode, on one hand, the macrocyclic π system of FePc enabled a rapid redox process, which facilitates electron transfer, thereby greatly improving sensitivity. On the other hand, by coordination with histamine on the electrode surface, FePc can enhance the electrochemical oxidation activity toward NO and promote catalytic detection, which have been revealed by electrochemical characterizations and density functional theory theoretical calculations. The designed electrochemical microsensor exhibits a low limit of detection (0.03 nM) and shows a wide detection range (0.1 nM-2 µM). In addition, the electrochemical microsensor has been successfully used for real-time monitoring of NO release by live cells. So, this work shows a new strategy for the design of bio-inspired electrochemical microsensors that may provide a potential analytical tool for tracing biological signal molecules with enzyme-free biomimetically catalytic centers.


Assuntos
Histamina , Óxido Nítrico , Microeletrodos , Compostos Ferrosos/química , Eletrodos , Técnicas Eletroquímicas
10.
Biomed Opt Express ; 14(4): 1480-1493, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078051

RESUMO

Laser speckle contrast imaging (LSCI) provides full-field and label-free imaging of blood flow and tissue perfusion. It has emerged in the clinical environment, including the surgical microscope and endoscope. Although traditional LSCI has been improved in resolution and SNR, there are still challenges in clinical translations. In this study, we applied a random matrix description for the statistical separation of single and multiple scattering components in LSCI using a dual-sensor laparoscopy. Both in-vitro tissue phantom and in-vivo rat experiments were performed to test the new laparoscopy in the laboratory environment. This random matrix-based LSCI (rmLSCI) provides the blood flow and tissue perfusion in superficial and deeper tissue respectively, which is particularly useful in intraoperative laparoscopic surgery. The new laparoscopy provides the rmLSCI contrast images and white light video monitoring simultaneously. Pre-clinical swine experiment was also performed to demonstrate the quasi-3D reconstruction of the rmLSCI method. The quasi-3D ability of the rmLSCI method shows more potential in other clinical diagnostics and therapies using gastroscopy, colonoscopy, surgical microscope, etc.

11.
Biosens Bioelectron ; 231: 115297, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37031505

RESUMO

Early screening of biomarkers benefits therapy and prognosis of cancers. MiRNAs encapsulated in tumor-derived exosomes are emerging biomarkers for early diagnosis of cancers. Nevertheless, traditional methods suffer certain drawbacks, which hamper their wide applications. In this contribution, we have developed a convenient electrochemical approach for quantification of exosomal miRNA based on the assembly of DNA triangular pyramid frustum (TPF) and strand displacement amplification. Four single-stranded DNA helps the formation of primary DNA triangle with three thiols for gold electrode immobilization at the bottom and three amino groups on overhangs for the capture of silver nanoparticles. On the other hand, target miRNA induced strand displacement reaction produces abundant specific DNA strands, which help the DNA structural transition from triangle to TPF. Amino groups are thus hidden and the declined silver stripping current can be used for the evaluation of target miRNA concentration. This biosensor exhibits excellent analytical performances and successfully achieves analysis of exosomal miRNAs from cells and clinical serum samples.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , MicroRNAs/análise , Nanopartículas Metálicas/química , Prata/química , Técnicas Biossensoriais/métodos , DNA/genética , DNA/química , Técnicas Eletroquímicas/métodos , Limite de Detecção
12.
Biosens Bioelectron ; 228: 115226, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36934606

RESUMO

Circular RNAs (circRNAs) can act as molecular sponges of microRNA (miRNA) to form circRNA-miRNA axis, which regulates the expressions of downstream proteins. Although the mechanism has been widely reported in various bioprocesses, there is still a lack of reliable and facile way to intuitively monitor and locate the interaction between circRNA and miRNA inside living cells. In this study, multiple DNA probes are designed and loaded onto two-dimensional Cu metal-organic framework (2D Cu-MOF) nanosheets for one-step analysis of circRNA-miRNA axis. The nanosheets serve as not only powerful fluorescence quenchers but also excellent nanocarriers of abundant DNA probes for further assembly. The Probes@Cu-MOF complex can be applied to track the circRNA-miRNA axis in living cells with high sensitivity and co-localization analysis. This platform combines the transmembrane advantage of nanosheets and the signal amplification ability of localized DNA cascade assembly, so it holds great potential for understanding the biological functions of circRNA-miRNAs in cancer pathogenesis and for therapeutic applications.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , MicroRNAs , MicroRNAs/genética , RNA Circular/genética , DNA
13.
Small Methods ; 7(2): e2201334, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36572635

RESUMO

The detection of deep-seated lesions is of great significance for biomedical applications. However, due to the strong photon absorption and scattering of biological tissues, it is challenging to realize in vivo deep optical detections, particularly for those using the safe laser irradiance below clinical maximum permissible exposure (MPE). In this work, the combination of ultra-bright surface-enhanced Raman scattering (SERS) nanotags and transmission Raman spectroscopy (TRS) is reported to achieve the non-invasive and photosafe detection of "phantom" lesions deeply hidden in biological tissues, under the guidance of theoretical calculations showing the importance of SERS nanotags' brightness and the expansion of laser beam size. Using a home-built TRS system with a laser power density of 0.264 W cm-2 (below the MPE criteria), we successfully demonstrated the detection of SERS nanotags through up to 14-cm-thick ex vivo porcine tissues, as well as in vivo imaging of "phantom" lesions labeled by SERS nanotags in a 1.5-cm-thick unshaved mouse under MPE. This work highlights the potential of transmission Raman-guided identification and non-invasive imaging toward clinically photosafe cancer diagnoses.


Assuntos
Neoplasias , Análise Espectral Raman , Camundongos , Animais , Suínos , Análise Espectral Raman/métodos , Luz , Ouro/química
14.
Biosens Bioelectron ; 220: 114900, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379172

RESUMO

Accurate and sensitive analysis of biomarkers is a promising way to provide comprehensive physio-pathological information that is significant for early diagnosis of certain diseases. miRNA is a type of noncoding small RNAs which are involved in the regulation of a number of cellular processes. It has been regarded as an important tumor biomarker. Herein, we have constructed a three-dimensional DNA layer on electrode interface and achieved ladder hybridization chain reaction strategy for the enrichment of electrochemical signals. In addition, duplex-specific nuclease catalyzed amplification is previously performed on magnetic nanocomposites, which further improves the sensitivity for the detection of target miRNA initiator. This approach shows great molecular recognition efficiency as well as cascade signal amplification. The analytical performances are superior. In addition, the identification of cancer cell types according to target biomarker information is achieved and the testing results in clinical serum samples further demonstrate its great potential utility for diagnosis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Técnicas Biossensoriais/métodos , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Hibridização de Ácido Nucleico/métodos , DNA/genética , DNA/química , Limite de Detecção
15.
Artigo em Inglês | MEDLINE | ID: mdl-36286204

RESUMO

Hydrogel has been widely used in modern biotherapeutics due to its excellent biocompatibility, degradability, and high drug loading capacity. Among them, the construction of a phototherapy system including photosensitizer and hydrogel has aroused great interest in tumor therapy. Unfortunately, complex modifications are necessary to integrate different photosensitizers into the hydrogel. In this work, an injectable hydrogel was proposed by the Schiff base reaction between HA-CHO and carbon dots (CDs), which can realize PTT and PTT simultaneously. Notably, the CDs with rich -NH2 can be used not only as a photosensitizer but also as an efficient cross-linking agent for the Schiff base reaction to form a hydrogel network. The CD@Hydrogel with outstanding biosafety showed a high antitumor effect after 660 nm laser irradiation in in vitro and in vivo experiments. In summary, the CD@Hydrogel can not only realize PTT and PDT synergistic treatment under one light source but also act as a cross-linking agent to react with HA-CHO to form hydrogel, which is simple and efficient, providing a new strategy for cancer phototherapy.

16.
Langmuir ; 38(36): 11130-11135, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36045009

RESUMO

MicroRNAs (miRNAs) are a family of endogenous noncoding RNAs with the functions of gene regulation, which serve as promising markers for a range of diseases such as diabetic foot ulcers, cancers, etc. In this work, we engineered a roll-to-roll DNA nanomachine for highly sensitive electrochemical detection of miRNA. A dumbbell-structured DNA probe could be transitioned to be wheel-structured conformation upon target recognition, which rolls around track strands on the surface of gold nanoparticles (AuNPs) in the presence of nicking endonuclease. The resulting single strands on AuNPs are activated for the second round of rolling at the DNA-modified electrode interface, leading to the variation of electrochemical responses. The roll-to-roll amplification behavior allows a wide detection range with a limit of detection as low as 10 aM. The practicability is also demonstrated by the application in human serum samples with satisfactory results. It is expected that the proposed electrochemical method offers a new paradigm to develop miRNA assays based on DNA nanotechnology.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , Técnicas Biossensoriais/métodos , DNA/química , DNA/genética , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , MicroRNAs/genética
17.
Anal Chem ; 94(28): 9975-9980, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35796492

RESUMO

A three-dimensional DNA tetrahedral nanostructure is constructed to support a walker strand on top and multiple track strands around it via the assembly of triplex-forming oligonucleotide (TFO). This design facilitates the regeneration of the sensing interface by simply adjusting pH conditions. On the basis of the tetrahedral DNA supported walking nanomachine, ultrasensitive electrochemical analysis of miRNA (miR-141) is achieved. Target miRNA assists the formation of three-way junction nanostructure. It contains a duplex region (hybridized by track and walker strands) that could be specially recognized and digested by certain nicking endonuclease. As a result, walker strand and target miRNA are released and move around the attached tracks for continuous cleavage reactions, releasing a larger number of signal reporters. By measuring the variation of signal responses, ultrasensitive analysis of miRNA is achieved. The limit of detection (LOD) is calculated to be 4.9 aM, which is rather low. In addition, the proposed method is successfully applied for the detection of miRNA in cell and serum samples, which could distinguish pathological information from healthy controls.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Neoplasias , Técnicas Biossensoriais/métodos , DNA/química , Técnicas Eletroquímicas/métodos , Limite de Detecção , MicroRNAs/análise
18.
J Nanobiotechnology ; 20(1): 181, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35392911

RESUMO

Cancer immunotherapy is limited by the immune escape of tumor cells and adverse effects. Photo-immunotherapy, the combination of immunotherapy and phototherapy (such as photodynamic therapy (PDT) and photothermal therapy (PTT)), can improve the effectiveness of immunotherapy in cancer treatment. Here, we first explored mesoporous hexagonal core-shell zinc porphyrin-silica nanoparticles (MPSNs), which are composed of a zinc porphyrin core and a mesoporous silica shell, and exhibit high laser-triggered photodynamic and photothermal activity, as well as outstanding drug loading capacity. In other words, MPSNs can be used not only as excellent photosensitizers for photo-immunotherapy, but also as an ideal drug carrier to achieve more efficient synergy. After loading with R837 (imiquimod, a toll-like receptor-7 agonist), MPSNs@R837 will elicit high-efficiency immunogenic cell death via PDT and PTT, and promote dendritic cell maturation after the PH-responsive release of R837, thereby, inducing tumor-specific immune responses. When combined with a programmed death ligand-1 checkpoint blockade, the photo-immunotherapy system markedly restrains primary tumors and metastatic tumors with negligible systemic toxicity. Therefore, the therapeutic strategy of integrating PTT, PDT and checkpoint blockade, shows great potential for suppressing cancer metastasis.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Linhagem Celular Tumoral , Imiquimode , Imunoterapia , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Fototerapia , Dióxido de Silício
19.
ACS Appl Mater Interfaces ; 14(15): 17119-17127, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35394762

RESUMO

It is well-known that the ratio of reduced l-glutathione (GSH) to oxidized l-glutathione (GSSG) is a vital biomarker for monitoring overall cellular health, thus detecting the intracellular concentration of glutathione is of great significance. Recently, an increasing number of reports have published various methods for GSH detection, but studies on the detection of GSSG are still rare. Here, we report a kind of new yellow fluorescent carbon dots (CDs) for the detection of GSSG through a fluorescence "off-on" process. Because the surface is rich in amino groups, the CDs show a positive potential. When the concentration of GSSG was continuously increased, the CDs' fluorescence dropped sharply, while the fluorescence gradually recovered after the addition of sodium sulfide. The phenomenon of fluorescence quenching is linear with the concentration of the quencher (GSSG)(0-200 µM), and 0.18 µM is calculated as the detection limit. More interestingly, as a fluorescent probe, the CDs can be further used for fluorescence imaging in living cells and zebrafish.


Assuntos
Corantes Fluorescentes , Pontos Quânticos , Animais , Carbono , Glutationa , Dissulfeto de Glutationa , Limite de Detecção , Espectrometria de Fluorescência/métodos , Peixe-Zebra
20.
Anal Chem ; 94(11): 4565-4569, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35266700

RESUMO

Manganese dioxide (MnO2) nanosheets are emerging for biomedical applications with excellent physical and chemical properties. Adsorption of DNA on MnO2 is important for biosensing, bioimaging, and therapy. Nevertheless, current fundamental understanding about the interaction is preliminary. Herein, UV-vis absorption spectra are applied to systematically explore the biointerfacial interaction between DNA and MnO2 with the factors of salt concentration, pH value, temperature, DNA concentration, and length. The results offer important fundamental insights into the investigation of DNA-MnO2 nanocomposites. Meanwhile, the optimal parameters are applied to construct a screen-printed electrode (SPE) modified with polymerase chain reaction (PCR) primer-decorated MnO2 nanosheets. An electrochemical PCR system is then developed for ultrasensitive detection of circulating tumor DNA (ctDNA). The limit of detection is determined to be 0.1 fM, and high selectivity is demonstrated. Combining the merits of SPE, DNA-MnO2 nanosheets, and an amplified reaction, this developed strategy shows great promise in bioanalysis, clinical disease diagnosis, and biomedicine applications.


Assuntos
Compostos de Manganês , Óxidos , DNA , Compostos de Manganês/química , Nanoconjugados , Óxidos/química , Reação em Cadeia da Polimerase
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