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1.
Biosens Bioelectron ; 255: 116269, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579624

RESUMO

Saxitoxin (STX), which is produced by certain dinoflagellate species, is a type of paralytic shellfish poisoning toxin that poses a serious threat to human health and the environment. Therefore, developing a technology for the convenient and cost-effective detection of STX is imperative. In this study, we developed an affinity peptide-imprinted polymer-based indirect competitive ELISA (ic-ELISA) without using enzyme-toxin conjugates. AuNP/Co3O4@Mg/Al cLDH was synthesized by calcining AuNP/ZIF-67@Mg/Al LDH, which was obtained by combining AuNPs, ZIF-67, and flower-like Mg/Al LDH. This synthesized nanozyme exhibited high catalytic activity (Km = 0.24 mM for TMB and 132.5 mM for H2O2). The affinity peptide-imprinted polymer (MIP) was imprinted with an STX-specific template peptide (STX MIP) on a multi-well microplate and then reacted with an STX-specific signal peptide (STX SP). The interaction between the STX SP and MIP was detected using a streptavidin-coated nanozyme (SA-AuNP/Co3O4@Mg/Al cLDH). The developed MIP-based ic-ELISA exhibited excellent selectivity and sensitivity, with a limit of detection of 3.17 ng/mL (equivalent: 0.317 µg/g). Furthermore, the system was validated using a commercial ELISA kit and mussel tissue samples, and it demonstrated a high STX recovery with a low coefficient of variation. These results imply that the developed ic-ELISA can be used to detect STX in real samples.


Assuntos
Técnicas Biossensoriais , Cobalto , Nanopartículas Metálicas , Óxidos , Humanos , Toxinas Marinhas/análise , Polímeros Molecularmente Impressos , Ouro , Peróxido de Hidrogênio , Frutos do Mar/análise , Saxitoxina , Ensaio de Imunoadsorção Enzimática/métodos , Peptídeos , Polímeros
2.
Biosens Bioelectron ; 246: 115902, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38056339

RESUMO

Extracellular protein kinase A autoantibody (ECPKA-AutoAb) has been suggested as a universal cancer biomarker due to its higher amounts in serum of several types of cancer patients than that of normal individuals. Herein, we first developed a lateral flow immunoassay (LFIA) tool, using a sandwich format, toward ECPKA-AutoAb in human serum. For this format, 3G2 as a capture antibody was identified using hybridoma technique and a series of screenings where it showed superior capacity to recognize Enzo PKA catalytic subunit alpha (Cα), compared to other PKA antibodies and antigens. Using these components, we performed sandwich ELISA toward a mimic and real sample of ECPKA-AutoAb. As per the results, limit of detection (LOD) was found to be 135 ng/mL and ECPKA-AutoAb levels were higher in various cancer patients than in normal individuals like previous studies. Based on these results, we applied this sandwich format into LFIA tool and found that the LOD of the fabricated LFIA tool showed about 3.8 ng/mL using spiked PKA-Ab, which is significantly improved compared to the LOD of sandwich ELISA. Also, the developed LFIA tool demonstrated a remarkable ability to detect significant differences in ECPKA-AutoAb levels between normal and cancer patients within 15 min, showing a potential for point-of-care (PoC) detection. One interesting point is that our LFIA strip contains an additional conjugation pad II, named because of its position behind the conjugation pad, in which PKA Cα is dried, enabling a sandwich format.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Neoplasias , Humanos , Autoanticorpos , Proteínas Quinases , Neoplasias/diagnóstico , Imunoensaio/métodos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Limite de Detecção , Testes Sorológicos
3.
J Fluoresc ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38109030

RESUMO

This study describes a new method for synthesizing water-soluble carbon dots (CDs) using "Curcuma longa" (green source) named CL-CDs via a single-step hydrothermal process. The as-synthesized CL-CDs exhibited greenish-yellow fluorescence at 548 nm upon excitation at 440 nm. It shows good water stability and exhibits a quantum yield of 19.4%. The developed probe is utilized for sensing triazophos (TZP) pesticide via a dynamic quenching mechanism, exhibiting favorable linearity ranging from 0.5-500 µM with a limit of detection of 0.0042 µM. The as-prepared CL-CDs probe was sensitive and selective towards TZP. Lastly, the successful application of the CL-CDs-based fluorescent probe in water and rice samples highlights its potential as a reliable and efficient method for the detection of TZP in various real sample matrices. Eventually, bioimaging and biocompatibility aspects of CL-CDs have been assessed on Saccharomyces cerevisiae (yeast) cell and lung cancer (A549) cell lines, respectively.

4.
J Fluoresc ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38109031

RESUMO

Fluorescent copper nanoclusters (Cu NCs) were synthesized by using Withania somnifera (W. somnifera) plant extract as a biotemplate. Aqueous dispersion of W. somnifera-Cu NCs displays intense emission peak at 458 nm upon excitation at 350 nm. This fluorescence emission was utilized for the detection of two pyrethroid pesticides (cypermethrin and lambda-cyhalothrin) via "turn-off" mechanism. Upon the addition of two pyrethiod pesticides independently, the fluorescence emission of W. somnifera-Cu NCs was gradually decreased with increasing concentrations of both pesticides. It was noticed that the decrease in emission intensity at 458 nm was linearly dependent on the logarithm of both pesticides concentrations in the ranges of 0.01-100 µM and of 0.05-100 µM for cypermethrin and lambda-cyhalothrin, respectively. Consequently, the limits of detection were found to be 27.06 and 23.28 nM for cypermethrin and lambda-cyhalothrin, respectively. The as-fabricated W. somnifera-Cu NCs acted as a facile sensor for the analyses of cypermethrin and lambda-cyhalothrin in vegetables (tomato and bottle gourd), which demonstrates that it could be used as portable sensing platform for assaying of two pyrethroid pesticides in food samples.

5.
ACS Omega ; 8(35): 31784-31800, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692247

RESUMO

The epidermal growth factor receptor (EGFR) is vital for regulating cellular functions, including cell division, migration, survival, apoptosis, angiogenesis, and cancer. EGFR overexpression is an ideal target for anticancer drug development as it is absent from normal tissues, marking it as tumor-specific. Unfortunately, the development of medication resistance limits the therapeutic efficacy of the currently approved EGFR inhibitors, indicating the need for further development. Herein, a machine learning-based application that predicts the bioactivity of novel EGFR inhibitors is presented. Clustering of the EGFR small-molecule inhibitor (∼9000 compounds) library showed that N-substituted quinazolin-4-amine-based compounds made up the largest cluster of EGFR inhibitors (∼2500 compounds). Taking advantage of this finding, rational drug design was used to design a novel series of 4-anilinoquinazoline-based EGFR inhibitors, which were first tested by the developed artificial intelligence application, and only the compounds which were predicted to be active were then chosen to be synthesized. This led to the synthesis of 18 novel compounds, which were subsequently evaluated for cytotoxicity and EGFR inhibitory activity. Among the tested compounds, compound 9 demonstrated the most potent antiproliferative activity, with 2.50 and 1.96 µM activity over MCF-7 and MDA-MB-231 cancer cell lines, respectively. Moreover, compound 9 displayed an EGFR inhibitory activity of 2.53 nM and promising apoptotic results, marking it a potential candidate for breast cancer therapy.

6.
Biosens Bioelectron ; 234: 115382, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37178497

RESUMO

C-reactive protein (CRP) is a phylogenetically highly conserved plasma protein found in blood serum, and an enhanced CRP level is indicative of inflammatory conditions such as infection and cancer, among others. In this work, we developed a novel high CRP-affinity peptide-functionalized label-free electrochemical biosensor for the highly sensitive and selective detection of CRP. Throughout biopanning with random peptide libraries, high affinity peptides for CRP was successfully identified, and then a series of synthetic peptide receptor, of which C-terminus was incorporated to gold binding peptide (GBP) as an anchoring motif was covalently immobilized onto gold nanoparticle (AuNPs) tethered polydopamine (PDA)‒black phosphorus (BP) (AuNPs@BP@PDA) nanocomposite electrode. Interaction between the CRP-binding peptide and CRP was confirmed via enzyme-linked immunosorbent assay along with various physicochemical and electrochemical analyses. Under the optimized experimental conditions, the proposed peptide-based biosensor detects CRP in the range of 0-0.036 µg/mL with a detection limit (LOD) of 0.7 ng/mL. The developed sensor effectively detects CRP in the real samples of serum and plasma of Crohn's disease patients. Thus, the fabricated peptide-based biosensor has potential applications in clinical diagnosis and medical applications.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanocompostos , Humanos , Proteína C-Reativa/análise , Ouro , Técnicas Eletroquímicas , Eletrodos , Peptídeos , Limite de Detecção
7.
Food Chem ; 422: 136243, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37141762

RESUMO

Okadaic acid (OA) is a type of marine biotoxin produced by some species of dinoflagellates in marine environments. Consumption of shellfish contaminated with OA can cause diarrhetic shellfish poisoning (DSP) in humans with symptoms that typically include abdominal pain, diarrhea and vomiting. In this study, we developed an affinity peptide-based direct competition enzyme-linked immunosorbent assay (dc-ELISA) for the detection of OA in real samples. The OA-specific peptide was successfully identified via M13 biopanning and a series of peptides were chemically synthesized and characterized their recognition activities. The dc-ELISA system showed good sensitivity and selectivity with a half-maximal inhibitory concentration (IC50) of 148.7 ng/mL and a limit of detection (LOD) of 5.41 ng/mL (equivalent, 21.52 ng/g). Moreover, the effectiveness of the developed dc-ELISA was validated using OA-spiked shellfish samples, and the developed dc-ELISA showed a high recovery rate. These results suggest that the affinity peptide-based dc-ELISA can be a promising tool for detecting OA in shellfish samples.


Assuntos
Alimentos Marinhos , Frutos do Mar , Humanos , Ácido Okadáico/análise , Frutos do Mar/análise , Alimentos Marinhos/análise , Anticorpos Monoclonais , Peptídeos
8.
J Enzyme Inhib Med Chem ; 38(1): 2202358, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37096560

RESUMO

Epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) protein tyrosine kinases co-expressed in various cancers such as ovarian, breast, colon, and prostate subtypes. Herein, new TAK-285 derivatives (9a-h) were synthesised, characterised, and biologically evaluated as dual EGFR/HER2 inhibitors. Compound 9f exhibited IC50 values of 2.3 nM over EGFR and 234 nM over HER2, which is 38-fold of staurosporine and 10-fold of TAK-285 over EGFR. Compound 9f also showed high selectivity profile when tested over a small kinase panel. Compounds 9a-h showed IC50 values in the range of 1.0-7.3 nM and 0.8-2.8 nM against PC3 and 22RV1 prostate carcinoma cell lines, respectively. Cell cycle analysis, apoptotic induction, molecular docking, dynamics, and MM-GBSA studies confirmed the plausible mechanism(s) of compound 9f as a potent EGFR/HER2 dual inhibitor with an effective antiproliferative action against prostate carcinoma.


Assuntos
Antineoplásicos , Carcinoma , Neoplasias da Próstata , Masculino , Humanos , Simulação de Acoplamento Molecular , Próstata , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proliferação de Células , Relação Estrutura-Atividade , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Receptores ErbB
9.
ACS Appl Bio Mater ; 6(4): 1621-1628, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-36972355

RESUMO

The lethality of the bovine viral diarrhea virus (BVDV) in cattle involves inapparent infection and various, typically subclinical, syndromes. Cattle of all ages are vulnerable to infection with the virus. It also causes considerable economic losses, primarily due to reduced reproductive performance. In the absence of treatment that can completely cure infected animals, detection of BVDV relies on highly sensitive and selective diagnosis methods. In this study, an electrochemical detection system was developed as a useful and sensitive system for the detection of BVDV to suggest the direction of diagnostic technology through the development of conductive nanoparticle synthesis. As a countermeasure, a more sensitive and rapid BVDV detection system was developed using the synthesis of electroconductive nanomaterials black phosphorus (BP) and gold nanoparticle (AuNP). To increase the conductivity effect, AuNP was synthesized on the BP surface, and the stability of BP was improved by using dopamine self-polymerization. Moreover, its characterizations, electrical conductivity, selectivity, and sensitivity toward BVDV also have been investigated. The BP@AuNP-peptide-based BVDV electrochemical sensor exhibited a low detection limit of 0.59 copies mL-1 with high selectivity and long-term stability (retaining 95% of its initial performance over 30 days).


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Vírus da Diarreia Viral Bovina , Nanopartículas Metálicas , Animais , Bovinos , Ouro , Doença das Mucosas por Vírus da Diarreia Viral Bovina/diagnóstico , Peptídeos
10.
Anal Chim Acta ; 1251: 341018, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-36925304

RESUMO

Influenza viruses are known to cause pandemic flu through inter-human and animal-to-human transmissions. Neuraminidase (NA), which is a surface glycoprotein of both influenza A and B viruses, is a minor immunogenic determinant; however, it has been proposed as an ideal candidate for a real testing. We successfully identified an affinity peptide which is specific to the influenza H5N1 virus NA via phage display technique and observed initially its binding affinities using enzyme-linked immunosorbent assay (ELISA). In addition, four synthetic peptides were chemically synthesized to develop an affinity peptide-based electrochemical biosensing system. Among all peptides tested, INA BP2 was selected as a potential candidate and subjected to square-wave voltammetry (SWV) for evaluating their detection performance. To enhance analytical performance, a three-dimensional porous bovine serum albumin (BSA)-MXene (BSA/MXene) matrix was applied. The surface morphology of the BSA/MXene film-deposited electrode was analyzed using X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Using SWV measurement, the BSA/MXene nanocomposite-based peptide sensor exhibited significant the dissociation constant (Kd = 9.34 ± 1.20 nM) and the limit of detection (LOD, 0.098 nM), resulting in good reproducibility, stability and recovery, even in the presence with spiked human plasma. These results demonstrate an alternative way of new bioanalytical sensing platform for developing more desirable sensitivity in other virus detection.


Assuntos
Técnicas Biossensoriais , Virus da Influenza A Subtipo H5N1 , Influenza Humana , Nanocompostos , Animais , Humanos , Soroalbumina Bovina/química , Influenza Humana/diagnóstico , Porosidade , Reprodutibilidade dos Testes , Peptídeos , Nanocompostos/química , Eletrodos , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção
11.
Molecules ; 28(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36771165

RESUMO

The bitter taste of M. charantia fruit limits its consumption, although the health benefits are well known. The thermal drying process is considered as an alternative method to reduce the bitterness. However, processing studies have rarely investigated physiochemical changes in fruit stages. The antioxidant activities and physiochemical properties of various fruit stages were investigated using different thermal treatments. The color of the thermally treated fruit varied depending on the temperature. When heat-treated for 3 days, the samples from the 30 °C and 90 °C treatments turned brown, while the color of the 60 °C sample did not change significantly. The antioxidant activities were increased in the thermally processed samples in a temperature-dependent manner, with an increase in phenolic compounds. In the 90 °C samples, the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity presented a 6.8-fold higher level than that of nonthermal treatment in mature yellow fruit (S3), whereas the activity showed about a 3.1-fold higher level in immature green (S1) and mature green (S2) fruits. Regardless of the stages, the carotenoid content tended to decrease with increasing temperature. In terms of antioxidant activities, these results suggested that mature yellow fruit is better for consumption using thermal processing.


Assuntos
Antioxidantes , Momordica charantia , Antioxidantes/análise , Carotenoides/análise , Momordica charantia/química , Fenóis/química , Frutas/química
12.
Luminescence ; 38(7): 1374-1384, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36758217

RESUMO

The fabrication of stable fluorescent MoNCs (molybdenum nanoclusters) in aqueous media is quite challenging as it is not much explored yet. Herein, we report a facile and efficient strategy for fabricating MoNCs using 2,3 dialdehyde maltose-cysteine Schiff base (DAM-cysteine) as a ligand for detecting myoglobin and γ-aminobutyric acid (GABA) in biofluids with high selectivity and sensitivity. The DAM-cysteine-MoNCs displayed fluorescence of bright blue color under a UV light at 365 nm with an emission peak at 444 nm after excitation at 370 nm. The synthesized DAM-cysteine-MoNCs were homogeneously distributed with a mean size of 2.01 ± 0.98 nm as confirmed by the high-resolution transmission electron microscopy (HR-TEM). Further, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) techniques were utilized to confirm the elemental oxidation states and surface functional groups of the DAM-cysteine-MoNCs. After the addition of myoglobin and GABA, the emission peak of DAM-cysteine-MoNCs at 444 nm was significantly quenched. This resulted in the development of a quantitative assay for the detection of myoglobin (0.1-0.5 µM) and GABA (0.125-2.5 µM) with the lower limit of detection as 56.48 and 112.75 nM for myoglobin and GABA, respectively.


Assuntos
Cisteína , Molibdênio , Cisteína/química , Espectroscopia de Infravermelho com Transformada de Fourier , Molibdênio/química , Maltose , Mioglobina , Micro-Ondas , Bases de Schiff , Espectrometria de Fluorescência , Corantes Fluorescentes/química , Ácido gama-Aminobutírico
13.
Org Lett ; 25(4): 647-652, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36682059

RESUMO

We present a novel nickel-catalyzed reaction of indole-tethered 2-alkynylphenol esters with various (hetero)aryl boronic acids, resulting in the synthesis of diversely functionalized pentacyclic benzofurocyclohepta[b]indole derivatives. This unprecedented cascade reaction involves the arylative cyclization of alkynes, nucleophilic attack of the indole moiety on the oxonium ion intermediate, 1,2-alkyl group migration, and aromatization. The synthesized molecules exhibit exceptional cytotoxicity against multiple cancer cell lines while maintaining biocompatibility toward healthy cells.

14.
Talanta ; 248: 123613, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653962

RESUMO

Identifying alternatives to antibodies as bioreceptors to test samples feasibly is crucial for developing next-generation in vitro diagnostic methods. Here, we aimed to devise an analytical method for detecting H1N1 viral proteins (hemagglutinin [HA] and neuraminidase [NA]) as well as the complete H1N1 virus with high sensitivity and selectivity. By applying biopanning of M13 peptide libraries, high affinity peptides specific for HA or NA were successfully identified. After selection, three different synthetic peptides that incorporated gold-binding motifs were designed and chemically synthesized on the basis of the original sequence identified phage display technique with or without two repeat. Their binding interactions were characterized by enzyme-linked immunosorbent assay (ELISA), square wave voltammetry (SWV), Time of flight-secondary ion mass spectroscopy (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS). The binding constants (Kd) of HA BP1, HA BP2 and NA BP1 peptides were found to be 169.72 nM, 70.02 nM and 224.49 nM for HA or NA proteins by electrochemical measurements (SWV). The single use of HA BP2 peptide enabled the detection of either H1N1 viral proteins or the actual H1N1 virus, while NA BP1 peptide exhibited lower binding for real H1N1 virus particles. Moreover, the use of both HA BP1 and BP2 as a divalent capturing reagent improved sensor performance as well as the strength of the electrochemical signal, thereby exhibiting a dual synergistic effect for the electrochemical detection of H1N1 antigens with satisfactory specificity and sensitivity (limit of detection of 1.52 PFU/mL).


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Neuraminidase/química , Peptídeos/química , Receptores de Peptídeos , Proteínas Virais
15.
Analyst ; 147(14): 3155-3179, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35730445

RESUMO

Lanthanide-doped upconversion nanoparticles (UCNPs) have gained more attention from researchers due to their unique properties of photon conversion from an excitation/incident wavelength to a more suitable emission wavelength at a designated site, thus improving the scope in the life sciences field. Due to their fascinating and unique optical properties, UCNPs offer attractive opportunities in theranostics for early diagnostics and treatment of deadly diseases such as cancer. Also, several efforts have been made on emerging approaches for the fabrication and surface functionalization of luminescent UCNPs in optical biosensing applications using various infrared excitation wavelengths. In this review, we discussed the recent advancements of UCNP-based analytical chemistry approaches for sensing and theranostics using a 980 nm laser as the excitation source. The key analytical merits of UNCP-integrated fluorescence analytical approaches for assaying a wide variety of target analytes are discussed. We have described the mechanisms of the upconversion (UC) process, and the application of surface-modified UCNPs for in vitro/in vivo bioimaging, photodynamic therapy (PDT), and photothermal therapy (PTT). Based on the latest scientific achievements, the advantages and disadvantages of UCNPs in biomedical and optical applications are also discussed to overcome the shortcomings and to improve the future study directions. This review delivers beneficial practical information of UCNPs in the past few years, and insights into their research in various fields are also discussed precisely.


Assuntos
Elementos da Série dos Lantanídeos , Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Luminescência , Nanopartículas/química , Neoplasias/diagnóstico , Neoplasias/terapia
16.
Bioelectrochemistry ; 145: 108090, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35240465

RESUMO

Caspase-3, a cysteine-dependent protease, is considered a reliable molecular biomarker for the diagnosis and prognosis of apoptosis-related diseases. In this study, we demonstrated a phage-based electrochemical biosensor for the evaluation of cell apoptosis by the sensitive and specific detection of caspase-3. Specifically, for screening of affinity peptide-displayed phages, phage display was performed using M13 phage libraries (cyclic forms of peptides), and we identified potential affinity peptide-displayed phage clones with the sequence CPTTMWRYC. After characterization of its binding affinity using enzyme-linked immunosorbent assay, whole phage particles were covalently attached to a gold surface using coupling chemistry (MUA-EDC/NHS). The developed phage sensor was characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM), electrochemical analysis using cyclic voltammetry (CV), and square wave voltammetry (SWV). Under optimal conditions, the affinity peptide-displayed phage sensor showed a good binding affinity (Kd = 0.13 ± 0.56 µM) and limit of detection (0.39 µM) for caspase-3 detection. Furthermore, developed phage sensor could be monitored the response of apoptotic HeLa cells by detecting caspase-3 activity. This work should stimulate the development of efficient alternative caspase-3 detection methods for the diagnosis and prognosis of apoptosis-related diseases.


Assuntos
Bacteriófago M13 , Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Caspase 3 , Técnicas Eletroquímicas , Células HeLa , Humanos , Peptídeos/química
17.
ACS Appl Mater Interfaces ; 13(31): 36697-36708, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34313117

RESUMO

Development of drug-delivery systems that allow simultaneous in vivo imaging has gained much interest. We report a novel strategy to encapsulate metal nanoparticles (NPs) within alginate gel for in vivo imaging. The cell lysate of recombinant Escherichia coli strain, expressing Arabidopsis thaliana phytochelatin synthase and Pseudomonas putida metallothionein genes, was encapsulated within the alginate gel. Incubation of alginate gel with metal ion precursors followed by UV irradiation resulted in the synthesis of high concentrations of metal NPs, such as Au, Ag, CdSe, and EuSe NPs, within the gel. The alginate gel with metal NPs was used as a drug-delivery system by further co-encapsulating doxorubicin and rifampicin, the release of which was made to be pH-dependent. This system can be conveniently and safely used for in vitro and in vivo bioimaging, enabled by the metal NPs formed within the gel matrix without using toxic reducing reagents or surfactants.


Assuntos
Alginatos/química , Portadores de Fármacos/química , Corantes Fluorescentes/química , Géis/química , Nanopartículas Metálicas/química , Aminoaciltransferases/genética , Aminoaciltransferases/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Arabidopsis/enzimologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Escherichia coli/genética , Células Hep G2 , Humanos , Masculino , Metalotioneína/genética , Metalotioneína/metabolismo , Metais/química , Camundongos Nus , Pseudomonas putida/enzimologia , Rifampina/química , Rifampina/farmacologia
18.
Anal Chim Acta ; 1146: 131-139, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33461708

RESUMO

Colorectal cancer (CRC) develops from polyps in the inner large intestine or rectum and an increasing incidence and high mortality rate has been observed in humans. Currently, colonoscopy is the preferred modality for early CRC diagnosis. However, this technique has several limitations, such as high medical costs and intricate procedures, leading to increasing demands for the development of a new, simple, and affordable diagnostic method. In this study, an advanced electrochemical biosensor based on rationally designed affinity peptides was developed for discriminating adenoma to carcinoma progression. Amino acid-substituted and rationally designed synthetic peptides (BP3-1 to BP3-8) based on in silico modeling studies were chemically synthesized, and covalently immobilized onto a gold electrode using aromatic ring compounds through surface chemistry techniques. The binding performance of the developed sensor system was observed using square wave voltammetry (SWV). The peptide BP3-2 was selected depending on its relative binding affinity; SWV indicated the limit of detection of BP3-2 for LRG1 to be 0.025 µg/mL. This sensor could distinguish the adenoma-carcinoma transition with improved binding abilities (specificity and selectivity), and stability in plasma samples spiked with LRG1 and real samples from patients with CRC. These results indicate that this electrochemical sensor system can be used for early monitoring of the colorectal adenoma to carcinoma progression.


Assuntos
Técnicas Biossensoriais , Neoplasias do Colo , Técnicas Eletroquímicas , Ouro , Humanos , Limite de Detecção , Peptídeos
19.
Bioelectrochemistry ; 137: 107670, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32971483

RESUMO

The recent extensive spread of Zika virus has led to increased interest in the development of early diagnostic tests. To the best of our knowledge, this is the first study to demonstrate the successful use of phage display to identify affinity peptides for quantitative analysis of AXL, a tyrosine kinase receptor involved in Zika virus entry. Biopanning of M13 phage library successfully identified a high affinity peptide, with the sequence AHNHTPIKQKYL. To study the feasibility of using free peptides for molecular recognition, we synthesized a series of amino acid-substituted peptides and examined their binding affinity for AXL using electrochemical impedance spectroscopy and square wave voltammetry. Most synthetic peptides had non-identical random coil structures based on circular dichroism spectroscopy. Of the peptides tested, AXL BP1 exhibited nanomolar binding affinity for AXL. To verify whether AXL BP1 could be used as a peptide inhibitor at the cellular level, two functional tests were carried out: a WST assay for cell viability and qRT-PCR for quantification of RNA levels in Zika virus-infected Huh7 cells. The results showed that AXL BP1 had low cytotoxicity and could block Zika virus entry. These results indicate that newly identified affinity peptides could potentially be used for the development of Zika virus entry inhibitors.


Assuntos
Peptídeos/farmacologia , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Receptores Proteína Tirosina Quinases/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Zika virus/fisiologia , Sequência de Aminoácidos , Linhagem Celular , Dicroísmo Circular , Espectroscopia Dielétrica , Ensaio de Imunoadsorção Enzimática , Humanos , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/metabolismo , Receptores Proteína Tirosina Quinases/fisiologia , Receptor Tirosina Quinase Axl
20.
Mater Sci Eng C Mater Biol Appl ; 110: 110545, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32204054

RESUMO

Photodynamic therapy is an emerging noninvasive cancer treatment approach, which requires a photosensitizer (PS), light, and molecular oxygen. In this study, we have successfully fabricated a dual nature (pH- and reactive-oxygen-species-responsive) upconversion nanoparticles (UCNPs) to utilize coloaded doxorubicin (DOX) and chlorin e6 (Ce6) with high antitumor efficacy. The model anticancer drug (DOX) and PS (Ce6) were conjugated in a ratio of 1:1 (w:w), and then loaded on the surface of UCNPs@mesoporous silica (mSiO2) (85.63 ± 9.87 nm). Cellular uptake could be achieved by either increased permeability or ionic effect of UCNPs@mSiO2, where Ce6 controlled the DOX release under a near-infrared (NIR) laser irradiation at 980 nm. A cytotoxicity analysis revealed that the dual-responsive UCNPs@mSiO2 could successfully deliver DOX and Ce6 at the tumor site, causing cell death with a high efficiency. This study shows that the modified UCNPs@mSiO2 is a promising system to realize NIR-light-triggered PS and drug delivery approach to improve synergistic therapies in vitro and in vivo, in the future.


Assuntos
Antineoplásicos , Doxorrubicina , Sistemas de Liberação de Medicamentos , Luz , Nanopartículas , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes , Dióxido de Silício , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/metabolismo , Neoplasias/patologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Dióxido de Silício/farmacologia
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