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1.
Chem Commun (Camb) ; 55(61): 8963-8966, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31290488

RESUMO

We develop a simple method for sensitive detection of alkaline phosphatase (ALP) based on the ligase amplification reaction-catalyzed assembly of a single quantum dot (QD)-based nanosensor. This nanosensor requires only a single ligase enzyme to achieve ultrahigh sensitivity with a detection limit of 5.63 × 10-7 U mL-1, and can be applied for kinetic analysis, inhibitor screening, and ALP measurement in cell extracts.


Assuntos
Fosfatase Alcalina/análise , Técnicas Biossensoriais/métodos , DNA Ligases/química , Ensaios Enzimáticos/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Pontos Quânticos/química , Biotina/química , Carbocianinas/química , DNA/química , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Fluorescência , Células HEK293 , Humanos , Limite de Detecção , Células MCF-7 , Hibridização de Ácido Nucleico , Imagem Individual de Molécula , Estreptavidina/química
2.
J Agric Food Chem ; 67(32): 9022-9031, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31339724

RESUMO

The quantitative multiplex immunochromatographic assay (mICA) has received an increasing amount of attention in multitarget detection. However, the quantitative results in the reported mICAs were obtained by recording the signals on the test lines that with which various analyte-independent factors readily interfere, resulting in inaccurate quantitation. The ratiometric strategy using the T/C value (ratios of signals on the test line to those of the control line) for signal correction can effectively circumvent these issues to enable more accurate detection. Herein, we present for the first time a novel ratiometric mICA strip with multiple T lines for the simultaneous quantitative detection of aflatoxin B1 (AFB1), fumonisin B1 (FB1), and ochratoxin A (OTA) using highly luminescent quantum dot nanobeads (QBs) as enhanced signal reporters. To achieve reliable ratiometric signal output, a biotin-streptavidin system was introduced to replace the conventional anti-mouse IgG antibody for reliable reference signals on the control line that are completely independent of the signal probe and analyte. By using stable T/C values as quantitative signals, our proposed QB-mICA method can successfully detect three mycotoxins with concentrations as low as 1.65 pg/mL for AFB1, 1.58 ng/mL for FB1, and 0.059 ng/mL for OTA. The detection performance of the developed QB-mICA strip, including precision, specificity, and reliability, was further evaluated using artificially contaminated cereal samples. The results demonstrate the improved accuracy and reliability of quantitative determination by comparison with the anti-mouse IgG antibody. Thus, this work provides a promising strategy for developing a ratiometric mICA method for accurately quantifying multiple analytes using the biotin-SA system, opening up a new direction in quantitative mICAs.


Assuntos
Aflatoxina B1/análise , Fumonisinas/análise , Imunoensaio/métodos , Ocratoxinas/análise , Animais , Biotina/química , Grão Comestível/química , Contaminação de Alimentos/análise , Imunoensaio/instrumentação , Luminescência , Camundongos , Micotoxinas , Pontos Quânticos , Estreptavidina/química
3.
Chem Asian J ; 14(17): 2953-2957, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31321878

RESUMO

This paper describes the synthesis of protein microtube motors having a urease interior surface and highlights their nonbubble-propelled behavior driven by enzymatic reaction (urea→NH3 and CO2 ). The precursor microtubes were prepared by layer-by-layer assembly using a track-etched microporous polycarbonate membrane. Immobilization of a urease on the internal wall was accomplished using avidin-biotin interaction. The tubules swam smoothly in an aqueous media containing a physiological concentration of urea. Each tubule was rotating laterally while moving forward. It is remarkable that the microtubes were digested completely by proteases, demonstrating perfect biodegradability.


Assuntos
Avidina/química , Biotina/química , Urease/metabolismo , Avidina/metabolismo , Biotina/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Cimento de Policarboxilato/química , Porosidade , Ureia/química , Ureia/metabolismo , Urease/química
4.
Anal Bioanal Chem ; 411(17): 3881-3890, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31152222

RESUMO

Aflatoxin B1 (AFB1) is one of the major mycotoxins, which naturally occurs in food and agricultural products. In this study, a cyclic peptide (CVPSKPGLC) mimicking AFB1 was used to develop a biotinylated peptide-based immunoassay (bp-ELISA) for AFB1 determination. This cyclic peptide was isolated from a commercially available phage-displayed random 7-mer cyclic peptide library, and then synthesized chemically. Instead of phage particles, the peptide was biotinylated and used to detect AFB1 by bp-ELISA, with an IC50 of 0.92 ng/mL, which was approximately 60-fold better than that of phage ELISA. Good recoveries (83-102%) were obtained in spiked rice and corn samples, which were further validated by high-performance liquid chromatography-fluorescence detector. As better sensitivities (0.92-1.21 ng/mL) were obtained by bp-ELISA even using selected anti-AFB1 antibodies prepared previously in laboratory, this cyclic peptide is suitable as a substitute for synthetic competitive AFB1 antigens in food contamination monitoring. Graphical abstract.


Assuntos
Aflatoxina B1/imunologia , Antígenos/química , Antígenos/imunologia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Biotina/química , Técnicas de Visualização da Superfície Celular , Cromatografia Líquida de Alta Pressão/métodos , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Contaminação de Alimentos/análise , Concentração Inibidora 50 , Limite de Detecção , Espectrometria de Fluorescência/métodos , Estreptavidina/química
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1122-1123: 83-89, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31173996

RESUMO

For magnetic control of cells for biomedical applications such as targeting of immune cells to tumors, cells must be magnetizable. For that, cells are incubated with superparamagnetic iron oxide nanoparticles (SPIONs) to take them up and thus become magnetizable. When using adherent cells, non-ingested SPIONs can be easily removed by rinsing of the particles regardless of their colloidal stability in cell culture medium. However, if suspension cells such as T cells are to be loaded with SPIONs, established methods to separate excess nanoparticles from cells are based on physicochemical parameters such as density, size or magnetizability. Thus, colloidal stability of the particles is of great importance, since only colloidally stable SPIONs can be completely separated from the cells due to their physicochemical differences. Aggregates of colloidally meta- or unstable particles cannot, however, be separated from cells due to their overlapping sizes and densities. Thus, development of an alternative method for the separation of nanoparticle aggregates from suspension cells is urgently needed. Here, we present an affinity chromatographic separation method based on immunohistochemical properties of the respective cells. A desthiobiotinylated antibody against a cellular surface antigen (here CD90.2 receptor on EL4 T cells) is immobilized on a streptavidin agarose column optimized for cell purification. Subsequently the column is loaded with the particle/cell suspension so that the cells bind to the column. After removing the particles by washing, the cells can be gently eluted with biotin solution under physiological conditions. This allows >95% of the excess iron concentration to be removed while maintaining cell viability.


Assuntos
Cromatografia de Afinidade/métodos , Separação Imunomagnética/métodos , Nanopartículas de Magnetita/química , Animais , Anticorpos/metabolismo , Biotina/química , Linhagem Celular , Sobrevivência Celular/fisiologia , Coloides/química , Camundongos , Estreptavidina/química
6.
J Mass Spectrom ; 54(8): 676-683, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240800

RESUMO

Detection of nucleic acids and single nucleotide polymorphisms (SNPs) is of pivotal importance in biology and medicine. Given that the biological effect of SNPs often is enhanced in combination with other SNPs, multiplexed SNP detection is desirable. We show proof of concept of the multiplexed detection of SNPs based on the template-directed native chemical ligation (NCL) of PNA-probes carrying a metal tag allowing detection using ICP-MS. For the detection of ssDNA oligonucleotides (30 bases), two probes, one carrying the metal tag and a second one carrying biotin for purification, are covalently ligated. The methodological limit of detection is of 29 pM with RSD of 6.7% at 50 pM (n = 5). Detection of SNPs is performed with the combination of two sets of reporter probes. The first probe set targets the SNP, and its yield is compared with a second set of probes targeting a neighboring sequence. The assay was used to simultaneously differentiate between alleles of three SNPs at 5-nM concentration.


Assuntos
Espectrometria de Massas/métodos , Ácidos Nucleicos/análise , Polimorfismo de Nucleotídeo Único , Sequência de Bases , Biotina/química , Cromatografia Líquida de Alta Pressão , Ligantes , Limite de Detecção , Metais/química , Oligonucleotídeos/análise , Estudo de Prova de Conceito , Estreptavidina/química
7.
Anal Bioanal Chem ; 411(21): 5383-5391, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31179527

RESUMO

Rapid, portable, and efficient detection of lead cations (Pb2+) is of great significance for monitoring and evaluating environmental toxicity and human healthcare. In this work, we developed a simple and low-cost homogenous fluorescence DNAzyme assay for Pb2+ determination based on Pb2+-dependent cleaving and rolling circle amplification (RCA). DNAzyme and its substrate (5'-biotin) formed double-stranded hybrids in solution which could thoroughly react with Pb2+ in aqueous phase. Then, the unreacted DNAzyme/substrate hybrids as well as cleaved parts with biotin labeling of substrate strand would be captured by magnetic beads through biotin-streptavidin interactions and removed from the reaction solution. Meanwhile, the other parts of the substrate strand remained in solution and subsequently acted as the primer and triggered RCA. The concentration of the cleaved substrate strand correlated to that of Pb2+ and non-specific amplification was effectively minimized through biotin-streptavidin isolation. With a smartphone camera, the fluorescence intensity was recorded and quantified after 30-90 min amplification, making it a portable method with minimum instrumentation. A dynamic range of 1-100 nM of Pb2+ was achieved under optimized conditions and it was successfully employed for Pb2+ detection in spiked lake water. Graphical abstract.


Assuntos
Técnicas Biossensoriais/métodos , DNA Catalítico/química , Chumbo/análise , Smartphone , Artefatos , Biotina/química , Cátions , Fluorescência , Corantes Fluorescentes/química , Limite de Detecção , Estudo de Prova de Conceito , Estreptavidina/química
8.
Inorg Chem ; 58(14): 9135-9149, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31241925

RESUMO

Prospective anticancer metallodrugs should consider target-specific components in their design in order to overcome the limitations of the current chemotherapeutics. The inclusion of vitamins, which receptors are overexpressed in many cancer cell lines, has proven to be a valid strategy. Therefore, in this paper we report the synthesis and characterization of a set of new compounds [Ru(η5-C5H5)(P(C6H4R)3)(4,4'-R'-2,2'-bpy)]+ (R = F and R' = H, 3; R = F and R' = biotin, 4; R = OCH3 and R' = H, 5; R = OCH3 and R' = biotin, 6), inspired by the exceptional good results recently obtained for the analogue bearing a triphenylphosphane ligand. The precursors for these syntheses were also described following modified literature procedures, [Ru(η5-C5H5)(P(C6H4R)3)2Cl], where R is -F (1) or -OCH3 (2). The structure of all compounds is fully supported by spectroscopic and analytical techniques and by X-ray diffraction studies for compounds 2, 3, and 5. All cationic compounds are cytotoxic in the two breast cancer cell lines tested, MCF7 and MDA-MB-231, and much better than cisplatin under the same experimental conditions. The cytotoxicity of the biotinylated compounds seems to be related with the Ru uptake by the cells expressing biotin receptors, indicating a potential mediated uptake. Indeed, a biotin-avidin study confirmed that the attachment of biotin to the organometallic fragment still allows biotin recognition by the protein. Therefore, the biotinylated compounds might be potent anticancer drugs as they show cytotoxic effect in breast cancer cells at low dose dependent on the compounds' uptake, induce cell death by apoptosis and inhibit the colony formation of cancer cells causing also less severe side effects in zebrafish.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Biotina/química , Ciclopentanos/química , Compostos de Rutênio/síntese química , Animais , Antineoplásicos/toxicidade , Biotina/farmacologia , Biotinilação , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Cristalografia por Raios X , Ciclopentanos/farmacologia , Humanos , Estrutura Molecular , Compostos de Rutênio/química , Compostos de Rutênio/farmacologia , Testes de Toxicidade , Peixe-Zebra
9.
Food Chem ; 294: 224-230, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126457

RESUMO

A novel high-sensitivity authentication method has been demonstrated for the rapid visual detection of adulterated meat based on both the lateral flow strip (LFS) platform and on polymerase chain reaction (PCR). After the rapid extraction of genomic components from meat, the on-site amplification of the target DNA of adulterated duck meat is carried out with the rationally designed functional FITC- and biotin-modified primer set, thereby producing numerous double-stranded DNA (dsDNA) products dually labelled with FITC and biotin. The FITC-labelled terminal end of the products binds to the pre-immobilized FITC antibody on the test line of the strip, and the biotin-labelled terminal end binds to the streptavidin-conjugated gold nanoparticles, resulting in a visible test line on the LFS for the rapid identification of duck meat in adulterated beef. After optimization, an adulteration ratio as low as 0.05% can be easily measured, which is more sensitive than other common adulteration authentication methods and is even comparable to instrumental methods. Moreover, 22 commercial processed meat samples were tested with this new strategy, and 4 adulterated samples were successfully identified by both the classic method and our method. In essence, the present authentication method is simple in design, convenient in operation, and can be easily extended to the identification of other adulteration components just by replacing the modified primers.


Assuntos
DNA/metabolismo , Carne/análise , Animais , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Biotina/química , Biotina/metabolismo , Bovinos , DNA/química , DNA/genética , Patos , Fluoresceína-5-Isotiocianato/química , Ouro/química , Nanopartículas Metálicas/química , Reação em Cadeia da Polimerase/métodos , Estreptavidina/química , Estreptavidina/metabolismo
11.
Talanta ; 200: 408-414, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036202

RESUMO

Extracellular vesicles (EVs) are cell-excreted membrane particles existing in a variety of biological fluids. As potential noninvasive biomarkers, EVs have received wide attention in recent years. However, usual EVs assays are complex, time-consuming and costly, thus limiting their clinical utility. Simple and rapid EVs quantification within biological fluids remains challenging. Here, we developed a simple, rapid strategy for EVs quantification, which combined with lateral flow assay and membrane biotinylation strategy. By utilizing biotin-functionalized phosphatidylethanolamine (DSPE-PEG-Biotin), the membrane of EVs could be successfully modified with biotin under strong hydrophobic interactions. Subsequently, based on the high affinity between streptavidin and biotin, quantification assay was achieved by lateral flow assay with fluorescent nanospheres (FNs) as a reporter. Biotinylation of biogenic EVs could be reached to 85%. This proposed method enables sensitive detection of 2.0 × 103 particles/µL. The whole procedure time was within 1 h. Furthermore, this approach was used to detect EVs in biological samples, demonstrating potential clinical applications.


Assuntos
Biotina/química , Biotinilação , Vesículas Extracelulares/química , Corantes Fluorescentes/química , Nanosferas/química , Fosfatidiletanolaminas/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Espectrometria de Fluorescência , Propriedades de Superfície , Células Tumorais Cultivadas
12.
Analyst ; 144(13): 3942-3948, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31086885

RESUMO

We report a smartphone compatible, low-cost porous silicon biosensor, which correlates the structural colour of a porous silicon microcavity (PSiM) to spectral peak position. Molecules captured in the PSiM cause a colour change that can be quantified through image analysis. Minimal external accessories are employed. Spectrometer measurements of the PSiM reflectance spectrum shifts are carried out concurrently with the smartphone measurements to benchmark the accuracy of the smartphone biosensor. We estimate that the smartphone biosensor supports an equivalent accuracy of 0.33 nm for the detection of colour changes corresponding to spectral shifts of the PSiM. Biosensing functionality is demonstrated using a biotin-streptavidin assay with an estimated detection limit of 500 nM. The PSiM-smartphone biosensor is a promising platform for label-free point of care diagnostics.


Assuntos
Técnicas Biossensoriais/instrumentação , Silício/química , Smartphone/instrumentação , Biotina/química , Cor , Limite de Detecção , Sistemas Automatizados de Assistência Junto ao Leito , Porosidade , Refratometria , Estreptavidina/química
13.
Analyst ; 144(13): 3959-3966, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31134974

RESUMO

MDM2 can mediate the degradation of tumor suppressor p53 through an autoregulatory feedback loop, in which MDM2 abolishes wild-type p53 function and accelerates malignant transformation. However, the incorporation of MDM2 antagonist Nutlin-3 could reactivate the transcriptional activity of p53, up-regulate caspase-3, and induce apoptosis. In this work, the simultaneous and label-free monitoring of p53-MDM2 complex and caspase-3 levels in cancer cells before and after Nutlin-3 treatment was conducted using dual-channel surface plasmon resonance (SPR). The p53-MDM2 complex was captured in one fluidic channel covered with consensus double-stranded (ds)-DNA, while the other channel was pre-immobilized with caspase-3-specific biotinylated DEVD-containing peptides. To amplify the SPR signals, the attachment of streptavidin (SA)-conjugated anti-MDM2 antibody in both channels was achieved. The signal diversity before and after Nutlin-3 treatment is indicative of the difference in the levels of the intracellular p53-MDM2 complex and caspase-3. The limit of detection for p53-MDM2 and caspase-3 down to 4.54 pM and 0.03 ng mL-1, respectively, was attained. Upon treatment with Nutlin-3, MCF-7 cancer cells with wild-type p53 showed decreased expression of the p53-MDM2 complex and an increased caspase-3 level, while MDA-MB-231 cancer cells with mutant p53 exhibited an elevated caspase-3 level and unchanged p53-MDM2 complex expression. The apoptosis of MCF-7 and MDA-MB-231 cancer cells upon Nutlin-3 treatment follows a p53-dependent and a p53-independent pathway, respectively. The proposed method is sensitive, selective and label-free, holding great promise for assaying intracellular p53-MDM2 complex and caspase-3 levels and differentiating Nutlin-3-mediated p53-dependent or p53-independent apoptotic pathways.


Assuntos
Caspase 3/análise , Imidazóis/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/análise , Ressonância de Plasmônio de Superfície/métodos , Proteína Supressora de Tumor p53/análise , Apoptose/efeitos dos fármacos , Biotina/química , Caspase 3/química , Caspase 3/metabolismo , Linhagem Celular Tumoral , DNA/química , Relação Dose-Resposta a Droga , Humanos , Limite de Detecção , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estreptavidina/química , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/metabolismo
14.
Molecules ; 24(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141958

RESUMO

Systems for efficient and selective capture of micro-scale objects and structures have application in many areas and are of particular relevance for selective isolation of mammalian cells. Systems for the latter should also not interfere with the biology of the cells. This study demonstrates the capture of microspheres through orthogonal coupling using biotin (ligand) and (strept)avidin (receptor). Fibrous poly(ethylene terephthalate) (PET) meshes were hydrolyzed under controlled alkaline conditions to obtain activated surfaces with COOH groups allowing for the functionalization of the PET with biotin of various spacer length. The system capture efficiency was optimized by varying the length of spacer presenting the biotin against streptavidin. In a proof of concept experiment, avidin-functionalized microspheres were used as surrogates for cells, and their capture under dynamic conditions including virous mixing and high-flow rate perfusion is demonstrated. Functionalization of PET meshes with biotin conjugated to longest spacer yielded the most efficient capture of microspheres. These preliminary results lay the foundation for the development of biosystems for capture of specific cells under physiologically relevant conditions, using biorthogonal avidin-biotin interactions.


Assuntos
Avidina/química , Biotina/química , Microesferas , Polímeros/química , Álcalis/química , Reatores Biológicos , Hidrólise , Perfusão , Polietilenotereftalatos/química
15.
Chem Commun (Camb) ; 55(35): 5159-5162, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30984931

RESUMO

We have reported a versatile nanopore method based on the combination of analyte-controlled liposome signal amplification and the nanopore detection of a reporter molecule, which largely extends the nanopore application range, and easily elevates the nanopore sensitivity to the fM level from the µM level.


Assuntos
Avidina/análise , Proteínas Hemolisinas/química , Nanoporos , Hormônio Liberador de Tireotropina/análise , Lipossomas Unilamelares/química , Biotina/química , Fosfatidilcolinas/química , Ácido Fítico/química
16.
Talanta ; 199: 164-169, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952241

RESUMO

A novel metal-enhanced chemiluminescence (MEC) signal tag was designed. By combining with a disposable immunosensor chip, an ultrasensitive immunoassay method was proposed for detection of C-reactive protein (CRP), an essential cerebrovascular disease marker. Two kinds of silver nanoparticle (AgNP) probes, DNA-hemin/DNA-A/biotin-DNA modified AgNPs (Probe A) and DNA-hemin/DNA-B modified AgNPs (Probe B) were prepared respectively. The MEC signal tag was formed by the link of Probe A and Probe B through the hybridization of DNA-A and DNA-B. The formed AgNP hybrid probes brought excellent CL signal amplification, due to the increased content of hemin molecules and the great MEC effect. The AgNP hybrid probes can be bound to the biotinylated antibody of sandwich immunocomplex for immunoassay of CRP. Under optimal conditions, the method showed a wide detection range of 7 × 10-7 to 0.07 mg mL-1 and a detection limit down to 0.05 ng mL-1. The results obtained with clinical serum samples were in acceptable agreement with reference values. The AgNP hybrid probes as well as the MEC-based immunoassay method showed great potentials in early clinical diagnosis of cerebrovascular disease.


Assuntos
Proteína C-Reativa/análise , Corantes Fluorescentes/química , Luminescência , Nanopartículas Metálicas/química , Prata/química , Biotina/química , DNA/química , Hemina/química , Humanos , Tamanho da Partícula , Propriedades de Superfície
17.
Drug Deliv ; 26(1): 499-508, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31033359

RESUMO

In this paper, the self-assembled folate-biotin-quaternized starch nanoparticles (FBqS NPs) were used as carrier system of doxorubicin (DOX) and siRNAIGF1R for the codelivery of both into human lung adenocarcinoma cell lines (A549 cells) in vitro. The cytotoxicity, targeted ligand competition, cell proliferation inhibition, cellular uptake, endocytosis mechanism and target protein suppression of drug-loaded FBqS NPs were evaluated in detail. Compared with several other drug formulations under same condition, siRNAIGF1R/DOX/FBqS NPs exhibited the greatest cytotoxicity to A549 cells and the cytotoxicity was competitively inhibited by free folate in dose-dependent manner. The A549 cells treated by siRNAIGF1R/DOX/FBqS NPs showed the lowest cell proliferation capacity. The energy-dependent clathrin- and caveolae-mediated endocytosis might be the primary cellular uptake mechanism of drug-loaded FBqS NPs. The expression of IGF1R protein in A549 cells treated by siRNAIGF1R/FBqS NPs declined dramatically. So the FBqS NPs were expected as the co-carrier system of chemotherapeutants and siRNAs for future clinical application.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Nanopartículas/química , RNA Interferente Pequeno/administração & dosagem , Células A549 , Antineoplásicos/farmacologia , Biotina/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Endocitose/efeitos dos fármacos , Ácido Fólico/química , Humanos , Neoplasias Pulmonares/patologia , Tamanho da Partícula , RNA Interferente Pequeno/farmacologia , Amido/química
18.
IET Nanobiotechnol ; 13(1): 6-11, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30964030

RESUMO

Circulating tumour cells (CTCs) draw significant attention as a promising biomarker for cancer prognosis, status monitoring, and metastasis diagnosis. However, the concentration of CTCs in peripheral blood is usually extremely low, thereby requiring enrichment followed by isolation of CTCs prior to detection. An immunomagnetic separation is a promising tool for CTCs enrichment. In this study, a cost-effective magnetic separation method, based on streptavidin-biotin complexation, was developed and the effects of magnetic beads' size in CTCs capture were compared. Magnetic nanobeads which were 25 nm in diameter lead to highest capture efficiency (82.2%) compared with 150 nm magnetic beads and 1 µm microbeads. Based on the streptavidin-biotin system, 25 nm magnetic nanobeads could capture model CTCs over 80% efficiency even at concentrations as low as ∼25 cells/mL that may represent the actual level of CTCs in peripheral blood of cancer patients. Furthermore, the isolated cells remained robust and healthy showing insignificant changes in morphology and behaviour when cultured for 24 h immediately after capture and isolation. The magnetic nanobeads based on streptavidin-biotin complexation showed promise for the easy and efficient capture and isolation of healthy CTCs for further diagnosis and analysis.


Assuntos
Proteínas de Bactérias/química , Biotina/análogos & derivados , Separação Imunomagnética/métodos , Nanopartículas de Magnetita/química , Células Neoplásicas Circulantes , Proteínas de Bactérias/metabolismo , Biotina/química , Biotina/metabolismo , Citometria de Fluxo , Humanos , Células K562 , Células MCF-7 , Tamanho da Partícula
19.
Mater Sci Eng C Mater Biol Appl ; 100: 676-687, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948104

RESUMO

Cervical cancer is one of the most occurring cancers and the fourth leading occurrence of cancer in women, worldwide. In this study, we planned to synthesis κ-Carrageenan grafted graphene oxide nanocarrier conjugated with biotin (GO-κ-Car-biotin) for targeted cervical cancer. Doxorubicin (DOX) is a well-known anticancer drug for any type of cancer and it is used to entrap over on the graphene oxide surface via π-π stacking interaction. The chemical function and crystalline nature of the synthesized nanocarrier was characterized by Fourier Transformed Infrared Spectroscopy (FT-IR) and X-ray diffraction Analysis (XRD). The surface morphological study was carried out through Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM) and Atomic force microscopy (AFM). The in-vitro drug release profile of DOX was carried out by UV-Vis spectrometer at the λmax value of 480 nm. The entrapment of DOX on GO-κ-car-biotin has been observed at 94%. The hydrophilic DOX drug has excellent pH-sensitive drug released in an in-vitro study. The anticancer efficiency of the synthesized GO-based nanocarrier was examined using HeLa cell line in-vitro. Cell viability, proliferation, cytotoxicity, and nuclear chromatin condensation was studied by trypan blue assay, triphosphate assay (ATP), lactate dehydrogenase assay (LDH) and Hoechst staining respectively. Finally, biotin leading GO-κ-Car carrier demonstrated is a promising drug delivery system for cervical cancer treatment.


Assuntos
Biotina/química , Carragenina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Grafite/química , Nanopartículas/química , Trifosfato de Adenosina/metabolismo , Carragenina/síntese química , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Liberação Controlada de Fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Células HeLa , Humanos , L-Lactato Desidrogenase/metabolismo , Microscopia de Força Atômica , Nanopartículas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X
20.
Methods Mol Biol ; 1977: 71-82, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30980323

RESUMO

Protein S-acylation (palmitoylation) is a reversible lipid modification that is increasingly recognized as an important regulator of protein function, including membrane association, trafficking, and subcellular localization. Most proteomic methods to study palmitoylation allow characterization of putative palmitoylated proteins but do not permit identification of individual sites of palmitoylation. We have recently adapted the Acyl-Biotin Exchange (ABE) method that is routinely used for palmitoyl-proteome characterization, to permit global S-acylation site analysis. This site-specific ABE (ssABE) protocol, when combined with SILAC-based quantification, allows both the large-scale identification of palmitoylation sites and quantitative profiling of palmitoylation site changes. This approach enables palmitoylation to be studied at a systems level comparable to other more intensively studied post-translational modifications.


Assuntos
Biotina/metabolismo , Proteína S/metabolismo , Proteômica , Acilação , Biotina/química , Cromatografia Líquida , Interpretação Estatística de Dados , Espectrometria de Massas , Proteômica/métodos , Coloração e Rotulagem , Espectrometria de Massas em Tandem , Fluxo de Trabalho
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