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1.
Ecotoxicol Environ Saf ; 272: 116041, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38350213

RESUMEN

Although PFOS has been banned as a persistent organic pollutant, it still exists in large quantities within the environment, thus impacting the health of aquatic ecosystems. Previous studies focused solely on high PFOS concentrations, disregarding the connection with environmental factors. To gain a more comprehensive understanding of the PFOS effects on aquatic ecosystems amidst changing environmental conditions, this study investigated the cellular responses of Microcystis aeruginosa to varying PFOS concentrations under heatwave and nutrient stress conditions. The results showed that PFOS concentrations exceeding 5.0 µg/L had obvious effects on multiple physiological responses of M. aeruginosa, resulting in the suppression of algal cell growth and the induction of oxidative damage. However, PFOS concentration at levels below 20.0 µg/L has been found to enhance the growth of algal cells and trigger significant oxidative damage under heatwave conditions. Heatwave conditions could enhance the uptake of PFOS in algal cells, potentially leading to heightened algal growth when PFOS concentration was equal to or less than 5.0 µg/L. Conversely, deficiency or limitation of nitrogen and phosphorus significantly decreased algal abundance and chlorophyll content, inducing severe oxidative stress that could be mitigated by exposure to PFOS. This study holds significance in managing the impact of PFOS on algal growth across diverse environmental conditions.


Asunto(s)
Microcystis , Ecosistema , Clorofila , Estrés Oxidativo , Fósforo/farmacología
2.
Anal Chem ; 95(8): 4220-4226, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36786428

RESUMEN

Bisphenol A (BPA), one of the most abundantly produced endocrine disrupting chemicals, is widely used in everyday plastic products and thus must be monitored. Multimode sensing platforms are able to combine the advantages of different strategies while solving the issues of inaccurate test results of single signal sensing. However, the exploration in this field is limited due to the compromise of sensing conditions and inevitable mutual interferences of different systems. Herein, we constructed a two-dimensional photonic crystal dually cross-linked supramolecular hydrogel (2DPCDCSH) by utilizing a host-guest pair of ß-cyclodextrin (ß-CD) and tert-butyl (t-Bu) as the second cross-linking for colorimetric and fluorescent dual-mode sensing of BPA. Based on the fact that BPA can act as a competitive guest to break the host-guest interaction between ß-CD and t-Bu, the cross-linking density decreased and an expansion-induced structural color change occurred. Sensitive and selective BPA detection can be easily achieved by measuring the Debye diffraction ring diameter or observing the color change of 2DPC with a detection limit of 1 µg mL-1. Moreover, the formation of the ß-CD/BPA complex gave a significant enhancement of the intrinsic fluorescence of BPA, obtaining a detection limit of 0.001 µg mL-1. The two sensing systems can share the same reaction condition and yield a wider dynamic response range than the single signal strategy. Overall, the proposed method presented an efficient, rapid, cost-effective, and regenerative dual-mode method for BPA analysis and shed new insights for the design of diversified sensing platforms.

3.
Opt Lett ; 48(24): 6400-6403, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38099758

RESUMEN

Laser beam steering is important for classical and quantum information processing. On-chip beam steering is a major motivation for developing large-scale photonic integrated circuits such as optical phased arrays. A major challenge for such arrays is to simultaneously control a large number of on-chip phase shifters, which requires a complicated analog control algorithm and rapidly increasing power consumption. We report a green light (532 nm) 1 × 16 focal plane array photonic integrated circuit with simple control and low power consumption. Fabricated on a silicon nitride platform, the focal plane array achieves angular beam steering over a 10° field of view, with ultra-low electrical power consumption (4 × 3.1 mW).

4.
Molecules ; 28(20)2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37894485

RESUMEN

Lowering blood cholesterol levels is crucial for reducing the risk of cardiovascular disease in patients with familial hypercholesterolemia. To develop Perilla frutescens (L.) Britt. leaves as a functional food with a cholesterol-lowering effect, in this study, we collected P. frutescens (L.) Britt. leaves from different regions of China and Republic of Korea. On the basis of the extraction yield (all components; g/kg), we selected P. frutescens (L.) Britt. leaves from Hebei Province, China with an extract yield of 60.9 g/kg. After evaluating different concentrations of ethanol/water solvent for P. frutescens (L.) Britt. leaves, with luteolin 7-glucuronide as the indicator component, we selected a 30% ethanol/water solvent with a high luteolin 7-glucuronide content of 0.548 mg/g in Perilla. frutescens (L.) Britt. leaves. Subsequently, we evaluated the cholesterol-lowering effects of P. frutescens (L.) Britt. leaf extract and luteolin 7-glucuronide by detecting total cholesterol in HepG2 cells. The 30% ethanol extract lowered cholesterol levels significantly by downregulating 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase expression. This suggests that P. frutescens (L.) Britt leaves have significant health benefits and can be explored as a potentially promising food additive for the prevention of hypercholesterolemia-related diseases.


Asunto(s)
Perilla frutescens , Humanos , Glucurónidos , Luteolina , Extractos Vegetales/farmacología , Solventes , Etanol , Colesterol , Agua , Hojas de la Planta
5.
Anal Chem ; 94(14): 5530-5537, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35357128

RESUMEN

The stimuli-responsive DNA hydrogel has attracted wide attention in the fields of chemical and biological sensing. However, it is still a challenge to integrate characteristics with low-cost, high mechanical strength, and signal self-expression into a DNA hydrogel simultaneously. Herein, a stimuli-responsive 2D photonic crystal double network DNA hydrogel (2D PhC DN-DNA hydrogel) sensing platform is developed via combining the signal self-expression of 2D PhC array with the selective recognition of polyacrylamide (PAM)/DNA DN hydrogel. The change of DNA configuration induced by specific target triggers the change of 2D PhC DN-DNA hydrogel volume, leading to a shift of the Debye diffraction ring diameter. In order to verify the feasibility of this strategy, the 2D PhC DN-DNA hydrogel with C-rich sequences is chosen as a proof-of-concept. The results indicate that the hydrogel has good detection performance for pH and Ag+/Cys. And the Debye diffraction ring diameter of the hydrogel is correlated with the concentration of the Ag+/Cys in the range of 0.5-20 µM. Compared with previously pure DNA hydrogel sensing platform, the 2D PhC DN-DNA hydrogel features low-cost preparation process and label-free determination. Meanwhile, only a laser pointer and a ruler are needed for the determination of targets, which shows that the hydrogel has application prospect in the development of portable response equipment.


Asunto(s)
Hidrogeles , Fotones , ADN/química , Hidrogeles/química
6.
Analyst ; 147(15): 3585-3592, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35822491

RESUMEN

There is an increasing need to develop simple yet effective sensors with high sensitivity, high selectivity, rapid response, and low cost for on-site detection of UO22+ in the environment in planned or emergency situations. Herein, we develop a UO22+ responsive interpenetrating porous photonic crystal ball (IPPCB) sensor by template replication and a two-step activation method. The amidoxime group and carboxyl group in the hydrogel drive the shrinkage of the hydrogel network through the coordination with UO22+, which reduces the lattice spacing, thereby changing the structure color and shifting the reflection peak position. Therefore, we can perform a semi-quantitative analysis of UO22+ with the naked eye or a fiber spectrometer. Benefiting from the sensor's spherical symmetry and periodic interpenetrating porous structure, the sensor can provide angle-independent, fast (12 min), and sensitive (minimum detection concentration of 1 nM) detection of UO22+. Moreover, IPPCBs have high selectivity and excellent regeneration performance, which can be applied to real sample detection.


Asunto(s)
ADN Catalítico , ADN Catalítico/química , Hidrogeles , Iones/química , Fotones , Porosidad
7.
Nano Lett ; 21(8): 3487-3494, 2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33848175

RESUMEN

Stimulated emission depletion (STED) nanoscopy plays a key role in achieving sub-50 nm high spatial resolution for subcellular live-cell imaging. To avoid re-excitation, the STED wavelength has to be tuned at the red tail of the emission spectrum of fluorescent probes, leading to high depletion laser power that might damage the cell viability and functionality. Herein, with the highly emissive silica-coated core-shell organic nanoparticles (CSONPs) enabling a giant Stokes shift of 150 nm, ultralow power STED is achieved by shifting the STED wavelength to the emission maximum at 660 nm. The stimulated emission cross section is increased by ∼20-fold compared to that at the emission red tail. The measured saturation intensity and lateral resolution of our CSONP are 0.0085 MW cm-2 and 25 nm, respectively. More importantly, long-term (>3 min) dynamic super-resolution imaging of the lysosomal fusion-fission processes in living cells is performed with a resolution of 37 nm.


Asunto(s)
Nanopartículas , Colorantes Fluorescentes , Rayos Láser , Microscopía Fluorescente , Dióxido de Silicio
8.
Anal Chem ; 93(34): 11887-11895, 2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34398607

RESUMEN

Herein, a novel liquid crystal microarray (LCM) film with optical regulation ability is first constructed by combining liquid crystals (LC) and the highly ordered microporous structure of inverse opal photonic crystals (IOPhCs). The LCM films are fabricated by infiltrating LC molecules into the LC polymer with the structure of IOPhCs, and their properties are very different from those without the LC. Interestingly, the optical property of LCM films can be controlled by changing the orientation of LC molecules, which varies with the interfacial force. In combination with polarization images, spectral reflection peak, circular dichroism spectra, potential difference, and fluorescence images of LCM films, the mechanism of this change is investigated. It is found that the exposed basic group of single-stranded DNA is the key to the change of the optical property of LC microarrays. Meanwhile, the optical signals of LC microarrays based on the PhCs provide a novel LC signal mode for an LC sensing system (microspectral signal mode), and it can be recorded by a fiber-optic spectrometer, which is a great improvement on LC sensing signals. Therefore, the LC microarray sensing signal can be used for accurate analysis of targets by the change of the reflection peak intensity of PhCs. When the LC molecules are induced by different aptamers, the LC microarray sensing interface can be further used for the determination of different targets, such as cocaine and Hg2+. The research on LCM films is of significant value for the development of LC sensing technology and also shows great application prospects in biochemical sensing fields.


Asunto(s)
Cristales Líquidos , Análisis por Micromatrices , Óptica y Fotónica , Fotones , Refractometría
9.
Analyst ; 146(2): 502-508, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33210667

RESUMEN

A simple penicillinase functionalized two-dimensional photonic crystal hydrogel (2DPPCH) biosensor was developed for colorimetric detection of penicillin G and penicillinase inhibitors. The penicillinase can specifically recognize penicillin G and catalyze it to produce penicilloic acid, which decreases the pH of the hydrogel microenvironment and shrinks the pH-sensitive hydrogel. The particle spacing decrease of the 2D photonic crystal array induced by the hydrogel shrinkage further causes a blue-shift in the diffraction wavelength. While the hydrolysis reaction is repressed upon treatment with clavulanate potassium (a kind of penicillinase inhibitor), no significant change in the diffraction wavelength is found. The detection of targets can be achieved by measuring the Debye diffraction ring diameter or observing the structural color change in the visible region. The lowest detectable concentrations for penicillin G and clavulanate potassium are 1 µM and 0.1 µM, respectively. Moreover, the 2DPPCH is proved to exhibit high selectivity and an excellent regeneration property, and it shows satisfactory performance for penicillin G analysis in real water samples.


Asunto(s)
Técnicas Biosensibles/métodos , Hidrogeles/química , Penicilina G/análisis , Penicilinasa/metabolismo , Fotones , Inhibidores de beta-Lactamasas/análisis , Inhibidores de beta-Lactamasas/farmacología
10.
Acta Biochim Biophys Sin (Shanghai) ; 53(3): 317-324, 2021 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-33432347

RESUMEN

Osteosarcoma (OS) is the most common type of primary malignant tumors that originate in the bone. Resistance to chemotherapy confers a poor prognosis on OS patients. Dysregulation of the epidermal growth factor receptor (EGFR) signaling has been reported in sarcomas. However, the functional contribution of EGFR hyperactivation to the tumor biology and chemoresistance remains largely unexplored in OS. In this study, we aimed to investigate the role of EGFR in OS progression and in the response of OS to gemcitabine treatment. The EGFR expression was found to be upregulated in fibroblastic OS cell lines. EGFR knockdown suppressed OS cell proliferation, migration, and invasion in vitro and tumor formation in vivo. Conversely, EGFR overexpression promoted the growth and motility of OS cells. In terms of mechanism, the levels of phospho-Akt and phospho-ERK were decreased upon EGFR knockdown but increased as a result of EGFR overexpression, implying a possible involvement of PI3K/Akt and ERK pathways in mediating the effects of EGFR on OS cells. Moreover, the level of phospho-EGFR was increased in OS cells when exposed to gemcitabine treatment. A more profound proliferative inhibition and a higher rate of apoptosis were obtained in OS cells via inducing cell cycle arrest at G1 phase upon gemcitabine treatment combined with EGFR knockdown, as compared to gemcitabine alone. On the contrary, EGFR overexpression counteracted the growth-inhibiting and pro-apoptotic effects of gemcitabine in OS cells. The present study suggests that EGFR promotes tumor progression and contributes to gemcitabine resistance in OS.


Asunto(s)
Neoplasias Óseas/metabolismo , Desoxicitidina/análogos & derivados , Resistencia a Antineoplásicos , Proteínas de Neoplasias/metabolismo , Osteosarcoma/metabolismo , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Línea Celular Tumoral , Desoxicitidina/farmacología , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Proteínas de Neoplasias/genética , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/genética , Osteosarcoma/patología , Gemcitabina
11.
Mikrochim Acta ; 188(6): 210, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-34047843

RESUMEN

A self-healing smart PhC hydrogel sensor that combines the optical property of photonic crystal and the dynamic regeneration property of boronate ester bond has been prepared for determination of glucose and related saccharides using Debye diffraction ring detection. The boronate ester bond formed through phenylboronic acid and dopamine endows the hydrogel network self-healing ability, and the tensile stress of the healing hydrogel can recover to 94.4%; this excellent self-healing property can effectively improve the reliability and lifetime of the hydrogel. Due to the high bonding capacity between 1,2- and 1,3-diol and phenylboronic acid, the hydrogel sensor has a good recognition ability for glucose and related saccharides. The reaction between the monosaccharides and the phenylboronic acid group makes the sensor swell and the diameter of the Debye diffraction ring decrease. The sensor shows good reuse and responsive ability for saccharides; the RSD of the recoverability assays is 4.3%. The determination range of the sensor to glucose is 0.5 to 12 mM. The sensor also has good response to glucose in urine, exhibiting potential application value in the preliminary screening of diabetes. Although the sensor has poor selectivity for specific monosaccharides, the process of measuring the Debye ring makes the determination no longer rely on expensive and complicated equipment and greatly simplifies the determining process and reduces the cost of determination, which shows a broad application prospect. The boronate ester bond formed through phenylboronic acid and dopamine results in the self-healing property of hydrogel network, which can effectively improve the reliability and lifetime of hydrogel. And due to the high bonding capacity between 1,2- and 1,3-diol and phenylboronic acid, the smart hydrogel sensor has a good recognition ability for glucose and related saccharides. The reaction between the monosaccharides and the phenylboronic acid group breaks the original boronate ester bond; this will lead to a decrease in cross-linking density of the PhC hydrogel sensor and further makes the sensor swell and the diameter of the Debye diffraction ring decrease.


Asunto(s)
Técnicas Biosensibles/métodos , Glucosa/análisis , Hidrogeles/química , Ácidos Borónicos/química , Fotones , Reproducibilidad de los Resultados , Rayos Ultravioleta
12.
Anal Chem ; 92(1): 924-931, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31800217

RESUMEN

Here, we report a surface-enhanced Raman scattering (SERS) nanosensor for real-time ratiometric detection of carbon monoxide (CO) based on a ligand displacement mechanism. This nanoprobe consists of a gold-silver (Au-Ag) alloy nanoparticle core as the highly active SERS substrate, an alkyne/ruthenium(II) (alkyne/Ru(II)) complex immobilized on the surface as the CO-sensing element, and a porous silica shell to improve the stability and biocompatibility of the particle. Displacement of the alkyne ligand by CO results in a decrease of the alkyne vibrations and an increase of the metal carbonyl complex signals, thus allowing the effective ratiometric detection of CO in real-time. The great potential of this assay for CO detection is validated in clean buffer environments, live cells, and tissue slices.


Asunto(s)
Alquinos/química , Monóxido de Carbono/análisis , Complejos de Coordinación/química , Rutenio/química , Espectrometría Raman/métodos , Aleaciones/química , Animales , Técnicas Biosensibles/métodos , Oro/química , Células Hep G2 , Humanos , Masculino , Nanopartículas del Metal/química , Ratones Endogámicos BALB C , Imagen Óptica/métodos , Dióxido de Silicio/química , Plata/química
13.
Analyst ; 145(16): 5624-5630, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32638707

RESUMEN

As an effective nuclear energy resource, uranium plays an important role in industry and energy but the wastes of uranium also cause radioactive contamination, which is harmful to the environment and the human body. Herein, a responsive photonic crystal (PC) film sensor for the ultrasensitive and label-free detection of uranyl ions (UO22+) has been proposed, which is easy to construct and does not need to be combined with a hydrogel. The PC film is not pH-sensitive because it is obtained by the self-assembly of methyl methacrylate-acrylonitrile co-polymeric nanospheres (PMMA-AN). These nanospheres were modified with amidoxime groups, which have a good coordination ability with UO22+. The bindings between nanospheres and UO22+ change the refractive index and disturb the face-centered cubic structure of the film, which leads to a decrease in the diffraction peak intensity of the PC film. The sensor works in the concentration range of 10 pM to 100 µM for UO22+ determination and the decreased intensities of the diffraction peaks are linearly correlated with the logarithm of UO22+ concentration in the range from 1 nM to 100 µM. Moreover, the sensor shows good selectivity for UO22+ and can also perform the determination of UO22+ in a real sample. The responsive PC film sensor shows great potential in the label-free and ultrasensitive detection of UO22+.

14.
Mikrochim Acta ; 187(8): 476, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32740762

RESUMEN

A low-angle-dependent photonic crystal hydrogel (LAD-PCH) material was developed to simultaneously detect and remove uranyl ions (UO22+). Different from traditional SiO2 photonic crystal hydrogel with the problem of angle dependency, the LAD-PCH material overcomes the restriction of observation direction. The LAD-PCH is a composite material with the photonic crystal array of 180-nm monodisperse CdS@SiO2 particles embedded into the functional hydrogel. As one UO22+ can bind to multiple carboxyl groups and amide groups, the functional hydrogel fabricated by acrylic acid and acrylamide will shrink after chelating. These changes in the hydrogel volume alter the array spacing and trigger a blue shift of diffraction wavelength and naked-eye visual color changes of LAD-PCH. The color can vary from orange-red to orange, yellow, green, and cyan, corresponding to the determination range of 100 pM-100 µM. The LAD-PCH material detects UO22+ sensitively as the lowest detectable concentration is about 100 pM, and removes UO22+ high-efficiently as the maximum adsorption capacity of U(VI) is about 1010 mg g-1 at 298 K. This LAD-PCH material is convenient and has potential to simultaneously monitor and remove UO22+ from uranium-polluted water. Schematic representation of the low-angle-dependent photonic crystal hydrogel (LAD-PCH) material for UO22+ detection and removal: The structural colors of LAD-PCH material overcome the restriction of observation angles. After the ligands complex with UO22+, the networks of LAD-PCH show different degrees of shrinkage; these volume changes of hydrogel trigger obvious naked-eye visual color changes of LAD-PCH.

15.
Environ Geochem Health ; 42(3): 849-861, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31093815

RESUMEN

Eutrophication has become great concern in recent years due to the fact that rivers, lakes, and reservoirs are the main drinking water source. Studies have been performed to enhance the removal of algae with ClO2 pre-oxidation, but there was high potential in the formation of chlorite and chlorate. In this study, ultra-sonication was employed to assist algae removal and control disinfection by-products formation in ClO2 pre-oxidation processes. It was found that solo ultra-sonication for 10 min (algae removal 86.11 ± 2.16%) could achieve similar algae removal efficiency as that with solo ClO2 (0.5 mg/L) pre-oxidation for 10 min (algae removal 87.10 ± 3.50%). In addition, no formations of chlorite and chlorate were detected in solo ultra-sonication process. Five-minutes ultra-sonication followed by 5-min 0.5 mg/L ClO2 treatment (total treatment time 10 min; algae removal 93.55 ± 3.22%) provided a better performance on algae removal compared to the solo ClO2 (0.5 mg/L) pre-oxidation for 10 min. Moreover, chlorite was undetectable. It suggests that the utilization of ultra-sonication in ClO2 pretreatment for algae removal has highly prevented the formations of chlorite and chlorate.


Asunto(s)
Compuestos de Cloro/química , Desinfección/métodos , Eutrofización , Óxidos/química , Sonicación/métodos , Purificación del Agua/métodos , Cloratos/química , Cloruros/química , Cloroformo/química , Oxidación-Reducción , Agua
16.
Anal Chem ; 91(7): 4529-4536, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30830752

RESUMEN

We report a ratiometric surface-enhanced Raman scattering (SERS) nanoprobe for imaging hypoxic living cells or tissues, using azo-alkynes assembled on a single-walled carbon nanotube (SWCNT) surface-functionalized with Ag/Au alloy nanoparticles (SWCNT/Ag/AuNPs). Under a hypoxic condition, azobenzene derivatives preassembled on the surface of the nanostructures are reduced stepwise by various reductases and eventually removed from the surface of the SWCNT/Ag/AuNPs, resulting in the loss of characteristic alkyne Raman bands at 2207 cm-1. Using 2D-band of SWCNTs at 2578 cm-1 as the internal standard, we are able to determine the hypoxia level based on the ratio of two peak intensities ( I2578/ I2207) as demonstrated by the successful detection in different cell lines and rat liver tissue samples derived from hepatic ischemia surgery. By combining the outstanding anti-interference property of alkynes as SERS reporters and the distinct Raman responses of alkynes and SWCNTs in complex systems, this novel ratiometric SERS strategy holds promise in becoming a very useful tool for in vitro and in vivo monitoring of hypoxia in research and clinical settings.


Asunto(s)
Alquinos/química , Oro/química , Isquemia/patología , Nanoconjugados/química , Nanotubos de Carbono/química , Plata/química , Espectrometría Raman/métodos , Animales , Hipoxia de la Célula , Línea Celular , ADN/química , Isquemia/metabolismo , Rayos Láser , Hígado/metabolismo , Hígado/patología , Microscopía Confocal , Ratas
17.
Mikrochim Acta ; 186(11): 724, 2019 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-31655900

RESUMEN

Liquid crystals (LCs) have the ability to transduce and amplify a molecular stimulus into optical signals due to their elastic and birefringence properties. An aptamer-based LC sensor for cocaine is described here. 3-Morpholinopropanesulfonic acid with amphipathic structure was used to establish recognition sites at a water/LC interface for the detection of cocaine. The cocaine-binding aptamer is formed at the interface. The conformation of the aptamer undergoes a change on binding cocaine, and this triggers the LCs anchoring transition from homeotropic to planar. Binding can also be detected by polarized optical microscopy. The fluorescence spectroscopy and circular dichroism results are used to prove that the conformation of aptamer changed from a hairpin structure to a special three-way junction structure on binding of cocaine at the interface. The assay works in the 1 nM to 10 µM cocaine concentration range and is specific. Graphical abstract Schematic representation of aptamer-based liquid crystal (LC) biosensor for the detection of cocaine. In this interface biosensing system, after the aptamer binding with cocaine, the conformation of aptamer at the aqueous/LC interface was changed from a hairpin structure to a special three-way junction structure. This triggered the Liquid crystals (LCs) anchoring transition from homeotropic to planar and the sign-on optical signal could be obtained by polarizing optical microscope (POM) in real-time.

18.
Biochem Biophys Res Commun ; 505(4): 959-965, 2018 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-30262140

RESUMEN

OBJECTIVE: Screening and identifying the gene mutation of EXT1, EXT2 and EXT3 associated with multiple exostosis (ME) and the expression in tumor tissues. METHODS: Nine patients with multiple exostosis were collected and genomic DNA was extracted. Polymerase chain reaction (PCR) amplification and direct sequencing techniques were used to screen all exons, 5' and 3' ends of the EXT1, EXT2 and EXT3 related causative genes. EXT1, EXT2 and EXT3 gene were screened and quantified by RNA-SEQ and RT-qPCR. The concentration of calcitonin gene-related peptide (CGRP) in peripheral blood of tumor patients and normal controls was detected by ELISA. RESULTS: Between the two patients with ME, the EXT1 gene was found in one patient to have c.79 T>A mutation, which caused the change of p.M27T, the non polar methionine was replaced by the high frequency mutation of polar threonine, and the rest of patients was found the splicing mutation c.1284 + 8 delAT of the heterozygosity of the EXT1 gene. The serum CGRP concentration of ME patients (623 + 49 pg/ml) was significantly higher than that of normal controls (196 + 68 pg/ml), and EXT1 mutation patients were also higher than non mutation patients.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/genética , Exostosis Múltiple Hereditaria/genética , N-Acetilglucosaminiltransferasas/genética , Péptido Relacionado con Gen de Calcitonina/sangre , Biología Computacional , Exostosis Múltiple Hereditaria/diagnóstico , Perfilación de la Expresión Génica , Humanos , Mutación
19.
Mikrochim Acta ; 185(12): 557, 2018 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-30465282

RESUMEN

A molecularly imprinted photonic hydrogel (MIPH) is described for the optical determination of L-histidine (L-His). The inverse opal structure of MIPH was obtained by placing silica particles (230 nm) in molecularly imprinted polymer on a glass slide. After being fully etched by hydrofluoric acid, this inverse opal structure brings about a high specific surface and plentiful binding sites for L-His. If L-His is absorbed by the modified MIPH, its average effective refraction coefficient is increased. This causes the Bragg diffraction peak to be red-shifted by about 34 nm as the concentration of L-His increases from 0 to 100 nM. Much smaller diffraction peak shifts are obtained for other amino acids. The detection limit of this method is 10 pM. The response time towards L-His is as short as 60 s. In addition, the sensor can be recovered by treatment with 0.1 M acetic acid/methanol. It was applied to the determination of L-His in drinks sample. Graphical abstract After absorbing L-histidine, the average effective refractive index of this molecularly imprinted photonic hydrogel (MIPH) is increased, and the Bragg diffraction peak is shifted. The shift of the diffraction peak can be used for the detection of L-His.

20.
Anal Chem ; 89(5): 2852-2858, 2017 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-28225598

RESUMEN

A novel aptasensor platform has been developed for quantitative detection of adenosine triphosphate (ATP) based on a ratiometric surface-enhanced Raman scattering (SERS) strategy. The thiolated 3'-Rox-labeled complementary DNA (cDNA) is first immobilized on the gold nanoparticle (AuNP) surface and then hybridizes with the 3'-Cy5-labeled ATP-binding aptamer probe (Cy5-aptamer) to form a rigid double-stranded DNA (dsDNA), in which the Cy5 and Rox Raman labels are used to produce the ratiometric Raman signals. In the presence of ATP, the Cy5-aptamer is triggered the switching of aptamer to form the aptamer-ATP complex, leading to the dissociation of dsDNA, and the cDNA is then formed a hairpin structure. As a result, the Rox labels are close to the AuNP surface while the Cy5 labels are away from. Therefore, the intensity of SERS signal from Rox labels increases while that from Cy5 labels decreases. The results show that the ratio between the Raman intensities of Rox labels and Cy5 labels is well linear with the ATP concentrations in the range from 0.1 to 100 nM, and the limit of detection reaches 20 pM, which is much lower than that of other methods for ATP detection and is also lower than that of SERS aptasensor for ATP detection. The proposed strategy provides a new reliable platform for the construction of SERS biosensing methods and has great potential to be a general method for other aptamer systems.

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