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The identification of tumor-related microRNAs(miRNAs)exhibits excellent promise for the early diag-nosis of cancer and other bioanalytical applications.Therefore,we developed a sensitive and efficient biosensor using polyadenine(polyA)-mediated fluorescent spherical nucleic acid(FSNA)for miRNA analysis based on strand displacement reactions on gold nanoparticle(AuNP)surfaces and electrokinetic signal amplification(ESA)on a microfluidic chip.In this FSNA,polyA-DNA biosensor was anchored on AuNP surfaces via intrinsic affinity between adenine and Au.The upright conformational polyA-DNA recognition block hybridized with 6-carboxyfluorescein-labeled reporter-DNA,resulting in fluores-cence quenching of FSNA probes induced by AuNP-based resonance energy transfer.Reporter DNA was replaced in the presence of target miRNA,leading to the recovery of reporter-DNA fluorescence.Sub-sequently,reporter-DNAs were accumulated and detected in the front of with Nafion membrane in the microchannel by ESA.Our method showed high selectivity and sensitivity with a limit of detection of 1.3 pM.This method could also be used to detect miRNA-21 in human serum and urine samples,with re-coveries of 104.0％-113.3％and 104.9％-108.0％,respectively.Furthermore,we constructed a chip with three parallel channels for the simultaneous detection of multiple tumor-related miRNAs(miRNA-21,miRNA-141,and miRNA-375),which increased the detection efficiency.Our universal method can be applied to other DNA/RNA analyses by altering recognition sequences.
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Objective To evaluate the radiosensitization effect and micro CT imaging of multifunctional gold nanoparticles in lung adenocarcinoma A549 tumor-bearing mouse models.Methods The tumor-bearing mice were injected with gold nanoparticles and irradiated with different energy levels of 160 kV and 6 MV X-ray.The tumor volume changes were measured.Intra-tumoral injection of gold nanoparticles was administered and micro CT scan was performed at different time points to observe the imaging and retention time of gold nanoparticles in the tumor tissues.Results The tumor volume did not significantly differ between the control and gold nanoparticles groups (P=0.941).The tumor volume in the 6 MV X-ray combined with gold nanoparticles group was slightly reduced compared with that in the 6 MV X-ray group with no statistical significance (P=0.730).The tumor volume in the 160 kV X-ray combined with gold nanoparticles group was significantly smaller than that in the 160 kV X-ray group (P=0.026).Micro CT scan demonstrated that gold nanoparticles could be deposited in the tumors for 30 d and yielded excellent imaging effect.No gold nanoparticles-induced toxicity was observed.Conclusions Multifunctional gold nanoparticles exert significant radiosensitization effect in the lung adenocarcinoma A549 transplanted tumors irradiated with 160 kV X-ray.Stable CT imaging of the gold nanoparticles-injected tumors can be used as a potential method for mapping and delineating the target area in tumor-guided radiotherapy.
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Objective To establish a simple and convenient method and study the feasibility of using gold nanoparticle composites (ssDNA-AuNPs) for colorimetric detection of gamma radiation.Methods The composites ssDNA-AuNPs were prepared by applying the ssDNA to the surface of AuNPs,and then were irradiated with gamma ray with absorbed doses of 0,5,10,20,and 30 Gy,respectively.Subsequently the color change in the solutions were observed simultaneously with absorption spectra being measured.The linear relationship between the ratio of A625/A521 in the absorption spectrum and the absorbed dose was established.Results With the increase of radiation dose,the color of the solutions changed from wine-red to blue-violet gradually,the ratio of A625/A521 in absorption spectra had excellent liner response for absorbed dose ranging from 0 to 30 Gy,and the linear equation was A625/A521 =0.020 6 + 0.303 6 E(R2 =0.991 5).Conclusions The ssDNA-AuNPs synthesized in this experiment can be successfully used for colorimetric detection of gamma absorbed dose,and a simple and convenient method for detection of gamma radiation has been newly established.
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Objective·To investigate the effect of gold nanoparticles (AuNPs) on exosome secretion of mesenchymal stem cells (MSCs) via blocking autophagy flux.Methods·Rat derived MSCs were treated with AuNPs (0,15,30,90,150 μg/mL),and the cell proliferation was detected with CCK-8 assay to evaluate the cytotoxicity of AuNPs.Then,MSCs were divided into normal control group,AuNPs group (20 μg/mL AuNPs for 72 h) and positive control group (5 μmol/L chloroquine for 4 h).Transmission electron microscopy was used to observe the ultrastructure of MSCs,and exosomes were extracted by ultracentrifugation and tested with nanoparticle analyzer and scan electron microscopy.The autophagy was observed by confocal microscopy and verified by Western blotting.Results·Low concentrations of AuNPs (0 to 30 μg/mL) slightly affected the cell proliferation.MSCs of AuNPs group secreted more abundant and smaller exosomes than those of control group,and expressed significantly more LC3 and p62 (both P＜0.05).Autophagosomes in AuNPs group were increased and fusion of lysosomes and autophagosomes was blocked.Conclusion·AuNPs block the autophagy flux and regulates the secretion of exosomes.
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Objective: To investigate the effect of gold nanoparticles (AuNPs) on exosome secretion of mesenchymal stem cells (MSCs) via blocking autophagy flux. Methods: Rat derived MSCs were treated with AuNPs (0, 15, 30, 90, 150 μg/mL), and the cell proliferation was detected with CCK-8 assay to evaluate the cytotoxicity of AuNPs. Then, MSCs were divided into normal control group, AuNPs group (20 μg/mL AuNPs for 72 h) and positive control group (5 μmol/L chloroquine for 4 h). Transmission electron microscopy was used to observe the ultrastructure of MSCs, and exosomes were extracted by ultracentrifugation and tested with nanoparticle analyzer and scan electron microscopy. The autophagy was observed by confocal microscopy and verified by Western blotting. Results: Low concentrations of AuNPs (0 to 30 μg/mL) slightly affected the cell proliferation. MSCs of AuNPs group secreted more abundant and smaller exosomes than those of control group, and expressed significantly more LC3 and p62 (both P<0.05). Autophagosomes in AuNPs group were increased and fusion of lysosomes and autophagosomes was blocked. Conclusion: AuNPs block the autophagy flux and regulates the secretion of exosomes.
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Nanotechnology is the engineering and manipulation of materials and devices with sizes in the nanometer range. Colloidal gold, iron oxide nanoparticles and quantum dot semiconductor nanocrystals are examples of nanoparticles, with sizes generally ranging from 1 to 20 nm. These nanotechnologies have been researched tremendously in the last decade and this has led to a new area of “nanomedicine” which is the application of nanotechnology to human healthcare for diagnosis, monitoring, treatment, prediction and prevention of diseases. Recently progress has been made in overcoming some of the difficulties in the human use of nanomedicines. In the mid-1990s, Doxil was approved by the FDA, and now various nanoconstructs are on the market and in clinical trials. However, there are many obstacles in the human application of nanomaterials. For translation to clinical use, a detailed understanding is needed of the chemical and physical properties of particles and their pharmacokinetic behavior in the body, including their biodistribution, toxicity, and biocompatibility. In this review, we provide a broad introduction to nanomedicines and discuss the preclinical and clinical trials in which they have been evaluated.
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Humans , Delivery of Health Care , Diagnosis , Gold Colloid , Iron , Nanomedicine , Nanoparticles , Nanostructures , Nanotechnology , Quantum DotsABSTRACT
Polymer-modified gold nanoparticles, which are more stable, less toxic to human body and have improved biocompatibility, have received intensive attention in biomedical applications, which can be used as or construct various therapy agents or carriers in cancer treatment. This review summarizes the current investigation of polymer-modified gold nanoparticles on their cancer treatment applications.
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Objective To synthesize novel gold nanoparticles of GAL-PEG-GNPs,study its radiation effect on hepatocellular carcinoma cells HepG2 cells in vitro,and investigate the underlying mechanisms.Methods GAL-PEG-GNPs were synthesized and characterized successfully.HepG2 cells were divided into three groups of control,GNPs and GAL-PEG-GNPs.The cytotoxicities of these compounds were tested by the CCK-8 assay and their IC50 values of HepG2 cells were calculated.Cell uptake of nanoparticles was detected by TEM and ICP-MS.The radiosensitization effect of nanoparticles was tested by the colony formation assay.Cell cycle distribution was detected by FCM.The expressions of CAT,SOD,and total GSH were detected with a microplate reader,and the expressions of apoptosis-related proteins were tested by Western blot.Results The GNPs and GAL-PEG-GNPs had absorption peaks at 520 and 530 nm,respectively,and their diameters were (22.6-±2.12) and (32.0 ± 1.41) nm detected by ICP-MS.The GAL-PEG-GNPs and GNPs had similar cytotoxicity profiles (P ＞ 0.05),while GAL-PEG-GNPs could be more effectively uptaken by HepG2 cells than GNPs.The sensitive enhancement ratio (SER) of GNPs and GAL-PEG-GNPs to HepG2 cells were 1.46 和 1.95,respectively.The percentage of cells at phase of G2/M in HepG2 population treated with GNP was higher than that of untreated cells (t =14.20,P ＜0.05).The protein expressions of Cytochrome C,Bax,Caspase-3,and Caspase-9 were upregulated while Bcl-2 expression was down-regulated in the cells treated with GNPs/radiation or GAL-PEGGNPs/radiation.The expressions of CAT,SOD and total GSH in the GNP treated groups were significantly decreased compared with the control group(t =12.34,29.39,12.85,P ＜ 0.05).Conclusions GALPEG-GNPs has obvious radiosensitization effect on HepG2 cells,which is related to the induction of cell apoptosis and the generation of free radicals.
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OBJECTIVE: To prepare a kind of novel multifunctional gold nanoshell coated magnetic nanoparticles and investigate their morphology, size distribution, two-photon optical properties, cellular uptake behavior, cytotoxicity as well as drug release profile. METHODS: In this study, the gold shell coated magnetic polyester nanoparticles (AuMPn) were prepared by emulsion solvent evaporation method combined with hydroxylamine reduction method. The size distribution, morphology, and two-photon optical properties were characterized by Zeta sizer, AFM, TEM and multiphoton confocal laser scanning microscopy respectively. The drug loading and release profile were evaluated by dialysis method using idarubicin as a model drug. RESULTS: The resultant AuMPn exhibit spherical shaped morphology with average size of (235.7±1.34) nm. The encapsulation efficiency and drug loading efficiency were 72.08% and 1.73% respectively. Under near infrared light irradiation, gold shell outside of AuMPn showed fingerprint like characteristic emission spectrum. The in vitro drug release study demonstrated that the release of idarubicin from AuMPn can be controlled by NIR irradiation. CONCLUSION: Overall, a novel gold shell coated nanoparticles are successfully prepared in this study. By taking advantage of the dual function of the gold shell outside of the particles, precise control on drug release as well as label-free visualization of AuMPn can be achieved simultaneously. Thus, this approach provides a new strategy for drug delivery.
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A peptide microarray-based fluorescence and resonance light scattering ( RLS ) two readout assay was developed for screening thrombin inhibitors in blood samples. In this assay, the biotinylated peptide microarray was used as the platform. The peptide C-terminal fragments carried biotin sites departed from the slide when the biotinylated peptides were digested by thrombin hydrolysis reaction. The hydrolysis progress was labeled by fluorescence and 30 nm peptide-stabilized gold nanoparticles through the biotin-avidin reaction. In the presence of thrombin inhibitors, the hydrolysis reactions were blocked, and the inhibition capability of inhibitors could be detected by the fluorescent and RLS signal changes. The order of the half maximal inhibitory concentration ( IC50 ) of thrombin inhibitors in pure thrombin solution and spiked human serum were argatrobanHAT-Ⅲ>trypsin inhibitor>E-64>AEBSF. The reversible or irreversible characters of argatroban and HAT-Ⅲ had been estimated in human plasma. Compared with the experimental data of fluorescent and RLS assay in blood sample, the RLS assay labeled by 30 nm gold nanoparticles are more suitable for the inhibitor detection in complicated blood sample.
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Nanoscience and Nanotechnology have found their way in the fields of pharmacology and medicine. The conjugation of drug to nanoparticles combines the properties of both. In this study, gold nanoparticle (GNP) was conjugated with NKCT1, a cytotoxic protein toxin from Indian cobra venom for evaluation of anti-arthritic activity and toxicity in experimental animal models. GNP conjugated NKCT1 (GNP-NKCT1) synthesized by NaBH4 reduction method was stable at room temperature (25±2 °C), pH 7.2. Hydrodynamic size of GNP-NKCT1 was 68–122 nm. Arthritis was developed by Freund's complete adjuvant induction in male albino rats and treatment was done with NKCT1/GNP-NKCT1/standard drug. The paw/ankle swelling, urinary markers, serum markers and cytokines were changed significantly in arthritic control rats which were restored after GNP-NKCT1 treatment. Acute toxicity study revealed that GNP conjugation increased the minimum lethal dose value of NKCT1 and partially reduced the NKCT1 induced increase of the serum biochemical tissue injury markers. Histopathological study showed partial restoration of toxic effect in kidney tissue after GNP conjugation. Normal lymphocyte count in culture was in the order of GNP-NKCT1>NKCT1>Indomethacine treatment. The present study confirmed that GNP conjugation increased the antiarthritic activity and decreased toxicity profile of NKCT1.
Subject(s)
Animals , Arthritis, Experimental/drug therapy , Arthritis, Experimental/pathology , Edema/drug therapy , Edema/pathology , Elapid Venoms/administration & dosage , Elapid Venoms/chemistry , Elapidae , Gold/administration & dosage , Gold/chemistry , Humans , Lymphocyte Count , Metal Nanoparticles/administration & dosage , Metal Nanoparticles/chemistry , Mice , RatsABSTRACT
Testes diagnósticos baseados na detecção de ácidos nucleicos sem amplificação prévia através da utilização de nanopartículas de ouro (AuNPs) têm sido descritos para várias enfermidades. Este trabalho teve como objetivo desenvolver uma técnica de AuNPs não modificada para detecção de Actinobacillus pleuropneumoniae (App). Utilizaram-se 70 amostras de pulmão de suínos, 17 sem lesão e 53 com lesões características de pneumonia, objetivando a detecção de App. O oligonucleotídeo utilizado foi baseado no gene ApxIV. O teste de AuNPs apresentou sensibilidade de 93,8 por cento e especificidade de 84,6 por cento quando comparado com a detecção pela PCR. Os resultados mostraram boa concordância entre os testes de AuNPs e a PCR, sendo que a técnica pode ser utilizada como alternativa aos testes convencionais, já que é de fácil e rápida execução e não exige infraestrutura e mão de obra especializada.
Based on diagnostic tests for the detection of nucleic acids without amplification through the use of gold nanoparticles (AuNPs) have been described for various diseases. This study aimed to develop a technique of unmodified AuNPs to detect Actinobacillus pleuropneumoniae (App). We used 70 lung samples from pigs, 17 with and 53 without characteristic lesions of pneumonia, to detect App. The primer used was based on ApxIV gene. The AuNPs test had a sensitivity of 93.8 percent and specificity of 84.6 percent when compared with PCR detection. The results showed good agreement between AuNPs and PCR testing, and the technique can be used as an alternative to conventional tests, since it is quick and easy, and does not require implementation infrastructure and skilled labor.
Subject(s)
Animals , Actinobacillus pleuropneumoniae/isolation & purification , Gold , Metal Nanoparticles , Lung/physiopathology , Swine/microbiology , Actinobacillus Infections/veterinary , Pneumonia/veterinary , Polymerase Chain Reaction/veterinaryABSTRACT
Objective To quantitatively detect CA125 with self-designed synthetic gold nanoparticle probes by the colorimetric immunoassay and to initially investigate the feasibility of clinical application .Methods The capture antibody of detective CA125 was conjugated to the gold nanoparticle surface for preparing the gold nanoparticle probes .The gold nanoparticle aggregation was formed by the antigen-antibody immunoreaction .CA125 was quantitatively detected by the colorimetric immunoassay .Results The gold nanoparticle probes was successfully prepared ,which could detect the serum CA125 content rapidly and conveniently ,the de-tection results were coincident with the pathological diagnosis .The lowest limit of quantitation was 0 .5 U/mL ,which was far lower than that in ELISA .Conclusion This gold nanoparticle probes are simple to be prepared ,rapid and easy to operate with low cost , and have the important application value in clinical early detection of ovarian cancer marker CA 125 ,especially in the primary hospi-tals .
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Peptide self-assembled multilayers ( SAMs ) was coated onto the quartz surface. The assembly conditions, such as the assembly agent concentration and assembly time, were examined. The SAMs was characterized via UV-vis absorption spectrometry and scanning electron microscope. Our results showed that the optimal concentration and assembly time for the 3-aminopropyl-triethoxysilane aqueous were 1% ( V/V ) and 3 h respectively, and those of gold nanoparticles were 2. 4 × 10-4 mol/L and 12 h, respectively, while those of peptide solution were 1 × 10-4 mol/L and 12 h, respectively. A new sensitive method, based on the theory that peptide could be cleaved at the site of Arg-Gly by thrombin, was established to detect thrombin. In addition, a good linear relationship was obtained in the range from 2. 8×10-12 mol/L to 9. 9×10-10 mol/L, and the detection limit was 1. 4×10-12 mol/L. The peptide self-assembled multilayers were also used in the analysis of blood serum samples, and the recovery rate was within the range from 91. 6% to 107. 6%.
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The 13 nm gold nanoparticles ( AuNPs ) were synthesized through the reduction of HAuCl4 by sodium citrate and the glutathione was assembled on the AuNPs. Under the experiment conditions, glutathione-modified AuNPs ( GSH-AuNPs ) with negative charge presented a wine red color owing to the electrostatic repulsion between nanoparticals. Upon the addition of neurogenin 3 ( ngn3 ) peptide, the aggregation of GSH-AuNPs was induced by ngn3 peptide under a certain concentration of salt. The color of AuNPs solution changed from red to blue as a function of the ngn3 peptide concentration. Thus, a rapid detection method for ngn3 peptide using GSH-AuNPs as colorimetric probe was established. The optimal experiment conditions were equilibrium time=10 min, pH=6. 0, CNaCl=100 mmol/L. Under the optimum conditions, the assay showed a linear response range of 20-300 μg/L for the peptide with a detection limit being 8 μg/L and exhibited excellent selectivity for ngn3 peptide.
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Three different seaweeds Gracilaria corticata J.Agardh ,Grateloupia lithophila Boergesen and Chaetomorpha antennina(Bory) kuetz used for the study were subjected for the estimation of carbohydrates, proteins, aminoacids, lipids and pigments such as chlorophyll a, chlorophyll b, carotenoid and phycobilins. They were also used for the nanoparticles synthesis and also checked for the blood glucose level changes by the oral administration of the seaweeds (0.5 g/day) to 6 mice for 20 days and with 3 mice as controls. The chaetomorpha, grateloupia and gracilaria estimation results showed 18.4%, 5.5%, 3.6% for carbohydrates, 15.8%, 30.5%, 23.7% for proteins, 4.9%, 22.94%, 11.04% for amino acids, 0.3%, 1.8%, 1.2% for lipids, 33.93, 1.35, 2.97 (mg/g fresh sample) for total chlorophyll, 0.2, 0.6, 5.49 (mg/g fresh sample) for carotenoid, 1.75, 2.1, 5.04 (μg/g fresh sample) for phycoerythrin respectively. They were also investigated for the extracellular biosynthesis of silver and gold nanoparticle and have achieved rapid formation of gold nanoparticles using Chaetomorpha antennina and Gracilaria corticata. It has been confirmed with the surface plasmon resonance.
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A simple and sensitive method was developed for the detection of mercury ions with quartz crystal microbalance(QCM), based on the specific thymine(T)-Hg2+-T structure and gold nanoparticles. The gold nanoparticles were prepared by the citrate reduction method. In a self-assembled way, the particle surface was modified with the probe oligonucleotides which were partially replaced by 6-Mercaptohexan-1-ol to reduce the steric hindrance of hybridization. The sensitivity was optimized by the oligonucleotide with a strand length of 9bp and a T number of 7. The linear range was 5.0-100 nmol/L with a detection limit of 2.0 nmol/L. And Ca2+, Mg2+ and other metal ions had no significant interferences. This method was successfully applied for the detection of Hg2+in environmental water samples, with RSD less than 2.9% and recoveries of 97.3%-101.2%.