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1.
Anal Chem ; 92(1): 1292-1300, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31855416

RESUMEN

We demonstrate an effective approach to realize active and real-time temperature monitoring around the gold nanobipyramids (AuNBPs)-labeled cancer cell under 808 nm laser irradiation by combining optical tweezers and temperature-sensitive upconversion microparticles (UCMPs). On the one hand, the aptamer-modified AuNBPs that absorb laser at 808 nm not only act as an excellent photothermal reagent but also accurately and specifically bind the target cancer cells. On the other hand, the single optically trapped NaYF4:Yb3+, Er3+ UCMPs with a 980 nm laser exhibit temperature-dependent luminescence properties, where the intensity ratio of emission 525 and 547 nm varies with the ambient temperature. Therefore, real-time temperature variation monitoring is performed by 3D manipulation of the trapped single UCMP to control its distance from the AuNBPs-labeled cancer cell while being photothermally killed. The results show distance-related thermal propagation because the temperature increase reaches as high as 10 °C at a distance of 5 µm from the cell, whereas the temperature difference drops rapidly to 5 °C when this distance increases to 15 µm. This approach shows that the photothermal conversion from AuNBPs is sufficient to kill the cancer cells, and the temperature increase can be controlled within the micrometer level at a certain period of time. Overall, we present a micrometer-size thermometer platform and provide an innovative strategy to measure temperature at the micrometer level during photothermal killing of cancer cells.


Asunto(s)
Luminiscencia , Nanopartículas/química , Pinzas Ópticas , Compuestos Orgánicos de Oro/química , Fototerapia , Temperatura , Células A549 , Células Cultivadas , Erbio/química , Células HEK293 , Calefacción , Humanos , Rayos Láser , Imagen Óptica , Compuestos Orgánicos de Oro/síntesis química , Factores de Tiempo , Iterbio/química , Itrio/química
2.
Anal Chem ; 92(7): 5258-5266, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32156113

RESUMEN

To enhance signal acquisition stability and diminish background interference for conventional flow bead-based fluorescence detection methods, we demonstrate here an exceptional microfluidic chip assisted platform by integrating near-infrared optical tweezers with upconversion luminescence encoding. For the former, a single 980 nm laser is employed to perform optical trapping and concurrently excite upconversion luminescence, avoiding the fluctuation of the signals and the complexity of the apparatus. By virtue of the favorable optical properties of upconversion nanoparticles (UCNPs), the latter is carried out by employing two-color UCNPs (Er-UCNPs and Tm-UCNPs) with negligible spectral overlaps. With the assistance of the double key techniques, we fabricated complex microbeads referred to a UCNPs-miRNAs-microbead sandwich construct by a one-step nucleic acid hybridization process and then obtained uniform terrace peaks for the automatic and simultaneous quantitative determination of miRNA-205 and miRNA-21 sequences with a detection limit of pM level on the basis of a special home-built flow bead platform. Furthermore, the technique was successfully applied for analyzing complex biological samples such as cell lysates and human tissue lysates, holding certain potential for disease diagnosis. In addition, it is expected that the flow platform can be utilized to investigate many other biomolecules of single cells and to allow analysis of particle heterogeneity in biological fluid by means of optical tweezers.


Asunto(s)
Luminiscencia , MicroARNs/análisis , Pinzas Ópticas , Células Cultivadas , Humanos , Rayos Infrarrojos , Rayos Láser , Microesferas , Nanopartículas/química , Tamaño de la Partícula , Propiedades de Superficie
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 545-50, 2017 Feb.
Artículo en Zh | MEDLINE | ID: mdl-30291776

RESUMEN

The traditional screening method of cervical cancer mainly involves TBS classification method and quantitative analysis method based on DNA, TBS screening method which has high diagnostic rate, but it needs experienced doctors to participate in the process with low sensitivity. Therefore, it is difficult to achieve early cervical cancer screening; cell's DNA quantitative analysis, only stained the nucleus, achieving a quantitative and automated analysis. Even with high sensitivity, the specificity is poor. So it is extremely necessary to realize the combination of screening for TBS and cell's DNA quantitative analysis, but the current TBS and DNA quantitative analysis combined screening method for the use of two different cell smear, time-consuming, laborious and very inconvenient, there is no screening method for cervical cancer on a combination of TBS and DNA quantitative analysis at home and abroad. This paper presents a method using TBS classification and DNA quantitative analysis on the same cell smear which was stained with Pap and Feulgen in order to solve the problem of the interference of the absorbance of DNA substance caused by multiple staining. a set of multi spectral imaging system and DNA absorbance peeling model are established based on linear multiple regression. With model solution, the real absorbance of the substance DNA was calculated, and the quantitative analysis of DNA was carried out. A pseudo color image is synthesized from 3 - band cell images with the close wavelength of RGB for TBS classification, so the organic combination of TBS and cell's DNA quantitative analysis is realized. Experiments show that the DNA quantitative analysis model of this method is stable, with small error and high diagnostic rate due to the fact that the pseudo color images used for TBS screening were bright, clear, and clear cytoplasm. Therefore, this method is very useful in the diagnosis and screening of cervical cancer.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias del Cuello Uterino , Núcleo Celular , Color , Citoplasma , ADN , Femenino , Humanos , Modelos Lineales , Tamizaje Masivo , Coloración y Etiquetado
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 496-501, 2016 Feb.
Artículo en Zh | MEDLINE | ID: mdl-27209757

RESUMEN

The conventional cervical cancer screening methods mainly include TBS (the bethesda system) classification method and cellular DNA quantitative analysis, however, by using multiple staining method in one cell slide, which is staining the cytoplasm with Papanicolaou reagent and the nucleus with Feulgen reagent, the study of achieving both two methods in the cervical cancer screening at the same time is still blank. Because the difficulty of this multiple staining method is that the absorbance of the non-DNA material may interfere with the absorbance of DNA, so that this paper has set up a multi-spectral imaging system, and established an absorbance unmixing model by using multiple linear regression method based on absorbance's linear superposition character, and successfully stripped out the absorbance of DNA to run the DNA quantitative analysis, and achieved the perfect combination of those two kinds of conventional screening method. Through a series of experiment we have proved that between the absorbance of DNA which is calculated by the absorbance unmixxing model and the absorbance of DNA which is measured there is no significant difference in statistics when the test level is 1%, also the result of actual application has shown that there is no intersection between the confidence interval of the DNA index of the tetraploid cells which are screened by using this paper's analysis method when the confidence level is 99% and the DNA index's judging interval of cancer cells, so that the accuracy and feasibility of the quantitative DNA analysis with multiple staining method expounded by this paper have been verified, therefore this analytical method has a broad application prospect and considerable market potential in early diagnosis of cervical cancer and other cancers.


Asunto(s)
Cuello del Útero/citología , ADN/análisis , Neoplasias del Cuello Uterino/diagnóstico , Núcleo Celular , Citoplasma , Femenino , Humanos , Coloración y Etiquetado
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2654-9, 2015 Sep.
Artículo en Zh | MEDLINE | ID: mdl-26669185

RESUMEN

Monitoring the consumption of nutrients of biological process helps control the growth environment of the microbes. It ensures the microbes are always in the best growing conditions, so as to maximize the yield of the target product. To monitor the content of glycerol, methanol and glucose in yeast culture medium, a new NIR spectrometer was developed which is based on Hadamard Transform (HT)technique. It uses the Near IR probe, which was designed all by ourselves, to collect the spectral signals, and uses the Digital Micro-mirror Devices(DMD) to complete the coding and modulation of Hadamard template. With self-developed software, aiming at spectral acquisition and spectral processing, the spectrometer has realized the real-time monitoring. The designs of optical path, Near IR probe, hardware circuit and software modules are given. Through lots of experiments, it turns out that the value of stray light is 0.875% and the volatility is ±4.28% in this spectrometer. The spectrometer shows high precision in a series of tests which means it totally meets the requirements of monitoring the biological processes.


Asunto(s)
Medios de Cultivo/química , Saccharomyces cerevisiae , Espectroscopía Infrarroja Corta , Fenómenos Biológicos , Glucosa , Glicerol , Luz , Metanol , Volatilización
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2357-61, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26672325

RESUMEN

An online Fourier Transform Infrared Spectrometer and an ATR (Attenuated Total Reflection) probe, specifically at the application of real time measurement of the reaction substrate concentration in biological processes, were designed. (1) The spectrometer combined the theories of double cube-corner reflectors and flat mirror, which created a kind of high performance interferometer system. The light path folding way was utilized to makes the interferometer compact structure. Adopting double cube-corner reflectors, greatly reduces the influence of factors in the process of moving mirror movement such as rotation, tilt, etc. The parallelogram oscillation flexible support device was utilized to support the moving mirror moves. It cancelled the friction and vibration during mirror moving, and ensures the smooth operation. The ZnSe splitter significantly improved the hardware reliability in high moisture environment. The method of 60° entrance to light splitter improves the luminous flux. (2) An ATR in situ measuring probe with simple structure, large-flux, economical and practical character was designed in this article. The transmission of incident light and the light output utilized the infrared pipe with large diameter and innerplanted-high plating membrane, which conducted for the infrared transmission media of ATR probe. It greatly reduced the energy loss of infrared light after multiple reflection on the inner wall of the light pipe. Therefore, the ATR probe obtained high flux, improved the signal strength, which make the signal detected easily. Finally, the high sensitivity of MCT (Mercury Cadmium Telluride) detector was utilized to realize infrared interference signal collection, and improved the data quality of detection. The test results showed that the system yields the advantages of perfect moisture-proof performance, luminous flux, online measurement, etc. The designed online Fourier infrared spectrometer can real-time measured common reactant substrates such as glycerin in the bioreactor under high quality. There is a large potential market, such as online analysis in biological, chemical testing and material analysis.


Asunto(s)
Espectroscopía Infrarroja por Transformada de Fourier , Reactores Biológicos , Fermentación , Rayos Infrarrojos , Luz , Reproducibilidad de los Resultados , Espectrofotometría Infrarroja
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2343-7, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26672322

RESUMEN

In order to improve moving mirror drive of Fourier transform infrared spectrometer, we design a dynamic scanning system based on flexible hinge support. Using the flexible hinge support way and the voice coil motor drive mode. Specifically, Using right Angle with high accuracy high stability type flexible hinge support mechanism support moving mirror, dynamic mirror can be moved forward and backward driven by voice coil motor reciprocating motion, DSP control system to control the moving mirror at a constant speed. The experimental results show that the designed of moving mirror scanning system has advantages of stability direction, speed stability, superior seismic performance.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1134-7, 2015 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-26197617

RESUMEN

For obtaining spectrum information and space distribution information of metameric targets at the same time, an AOTF-based imaging spectrometer was developed, which consists of a front imaging lens assembly, an AOTF filter imaging module, an AOTF driver, a plane array CCD, an image acquisition card and a PC. Under the control of the PC, a spectral image cube can be obtained by a fast wavelength scanning process, thereby the spectrum information of any point on the image is available. The developed imaging spectrometer, with a spectral range from 550-1,000 nm and a spectral resolution of 2.6 nm (@ 632 nm), and a less than 80 s switch time between any two wavelengths, has the characteristics of no mechanical moving part, low power dissipation and strong vibration resistance. The identification test of true and false roses and the information recovery experiment of altered physical evidence were carried out, The true and false roses were identified and the altered physical evidence was recovered, The experimental results showed that the imaging spectrometer has an excellent ability of identifying metameric targets, indicating a good application prospect.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1711-5, 2014 Jun.
Artículo en Zh | MEDLINE | ID: mdl-25358194

RESUMEN

Aiming at the existing problems such as weak environmental adaptability, low analytic efficiency and poor measuring repeatability in the traditional spectral oil analyzers, the present paper designed a portable mid-infrared rapid analyzer for oil concentration in water. To reduce the volume of the instrument, the non-symmetrical folding M-type Czerny-Turner optical structure was adopted in the core optical path. With a periodically rotating chopper, controlled by digital PID algorithm, applied for infrared light modulation, the modulating accuracy reached ±0.5%. Different from traditional grating-scanning spectrophotometers, this instrument used a fixed grating for light dispersion and avoided rotating error in the course of the measuring procedures. A new-type MEMS infrared linear sensor array was applied for modulated spectral signals detection, which improved the measuring efficiency remarkably. Optical simulation and experimental results indicate that the spectral range is 2 800 - 3 200 cm(-1), the spectral resolution is 6 cm(-1) (@3 130 cm(-1)), and the signal to noise ratio is up to 5 200 : 1. The acquisition time is 13 milliseconds per spectrogram, and the standard deviation of absorbance is less than 3 x 10(-3). These performances meet the standards of oil concentration measurements perfectly. Compared with traditional infrared spectral analyzers for oil concentration, the instrument demonstrated in this paper has many advantages such as smaller size, more efficiency, higher precision, and stronger vibration & moisture isolation. In addition, the proposed instrument is especially suitable for the environmental monitoring departments to implement real-time measurements in the field for oil concentration in water, hence it has broad prospects of application in the field of water quality monitoring.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 271-4, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23586271

RESUMEN

Imaging AOTF is an important optical filter component for new spectral imaging instruments developed in recent years. The principle of imaging AOTF component was demonstrated, and a set of testing methods for some key performances were studied, such as diffraction efficiency, wavelength shift with temperature, homogeneity in space for diffraction efficiency, imaging shift, etc.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 278-82, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23586273

RESUMEN

The acousto-optic tunable filter (AOTF) is the most outstanding progress of near-infrared spectrometer since the 1990s. Restriction in working range and performance of the device exists due to the traditional single-transducer structure. The design of a near-infrared acousto-optic tunable filter with high-throughput and wide-bandwidth adopting a dual-transducer structure is reported in the present paper. By calculation and simulation based on the wave vector diagram which satisfies the parallel-tangents condition, the optimal cutting direction and cutting angle of the acousto-optic crystal, the length of the transducers and other best parameters were obtained. The tuning range of the filter is improved significantly while the resolution, diffraction efficiency and other parameters satisfy the requirements by making two transducers working at the high-frequency part and low-frequency part respectively. According to the testing results of the designed filter, the spectrum resolution is better than 15 nm and the diffraction efficiency is reaches to 41% with the tuning range of 900-2 400 nm.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2294-8, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-24159897

RESUMEN

A novel interferometer system based on the combinations of cube-corner reflectors and fixed plane mirrors was designed, the moving mirror drive system was designed and analysed, and its governor PID algorithm was used to ensure that the movement of the moving mirror is collimated, uniform and smooth. The parameters of the optical system of the interferometer and the optical devices were described. Finally, after validation of the experiment, it was indicated that the wave number accuracy, resolution, signal to noise ratio and other key indicators can meet the needs of practical application.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(6): 1712-6, 2012 Jun.
Artículo en Zh | MEDLINE | ID: mdl-22870672

RESUMEN

A novel interferometer system based on the combinations of cube-corner reflectors and fixed plane mirrors was designed to improve the quality of spectra. It consists of a pair of cube corner reflectors, two fixed perpendicular plane mirrors and one beam splitter. By analyzing the modulation depth and phase error, the tilt and shearing of the cube corner reflectors, the deviation angle of cube corner reflector, the tilt of fixed plane mirrors and the deviation angle of two fixed plane mirrors were analyzed. It was proved that the tilt and shearing of the cube corner reflectors, and the deviation angle of two fixed plane mirrors, have no effects on the modulation depth and phase error of this new interferometer system, and the effect from the vibration, temperature fluctuations and other external environmental factors also can be effectively reduced, which can significantly improve the spectral resolution and quality. Through some experiments, it was found that the instrument has a simple structure, good sealing, high resolution, strong stability and other advantages

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(6): 1722-6, 2012 Jun.
Artículo en Zh | MEDLINE | ID: mdl-22870674

RESUMEN

A kind of two-dimensional hadamard transform spectrometer was developed. A grating was used for chromatic dispersion of orders and a prism was used for spectral dispersion. Quite different from traditional CCD detection method, a digital micromirror device (DMD) was applied for optical modulation, and a simple point detector was used as the sensor. Compared with traditional two-dimensional spectrometer, it has the advantage of high resolution and signal-noise-ratio, which was proved by theoretical calculation and computer simulation.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(10): 2874-8, 2011 Oct.
Artículo en Zh | MEDLINE | ID: mdl-22250575

RESUMEN

A Hadamard transform near infrared spectrometer based on a digital micromirror device was constructed. The optical signal was collected by optical fiber, a grating was used for light diffraction, a digital micromirror device (DMD) was applied instead of traditional mechanical Hadamard masks for optical modulation, and an InGaAs near infrared detector was used as the optic sensor. The original spectrum was recovered by fast Hadamard transform algrithms. The advantages of the spectrometer, such as high resolution, signal-noise-ratio, stability, sensitivity and response speed were proved by experiments, which indicated that it is very suitable for oil and food-safety applications.

16.
Analyst ; 134(3): 504-11, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19238287

RESUMEN

We report the development of Hadamard transform fluorescence spectral imaging microscopy by using a movable one-dimensional Hadamard mask to encode the image signals and a linear charge-coupled device (CCD) to detect the encoded spectral image signal. The technique has the ability of multi-spectral imaging and images with four dimensions: location coordinate (X and Y), fluorescence intensity (Z) and wavelength (lambda) (or time (t)) can be obtained. The results show that the system has high spectral resolving power (0.3 nm) and imaging capability, where image resolution up to 511 x 512 can be easily obtained for analysis of tiny samples. Multicolor imaging of acridine orange/ethidium bromide double-stained fibroblast treated with glyoxal shows that 1.5 mM glyoxal obviously causes apoptosis, thus demonstrating that identification of apoptotic cells can be realized using the Hadamard system not only through morphologic changes but also by the spectral evidences of the fluorescently stained cells. In addition, based on immunostaining with quantum dots (QDs) emitting at 550 and 610 nm to tag and trace two breast cancer biomarkers human epidermal growth factor receptor 2 (HER-2) and estrogen receptor (ER) in human breast cancer tissue with in situ dual-color fluorescence imaging, sensitive spectra and images were obtained and show that the system can be applied to visualize and quantitatively measure the subcellular proteins inside the tumor tissues, especially when a single laser line is used as the illuminating source for multi-components with different emission peaks. The preliminary biomedical applications indicate the great potential of the Hadamard imaging system as a useful tool in biomedicine.


Asunto(s)
Microscopía Fluorescente/métodos , Apoptosis/efectos de los fármacos , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/diagnóstico , Compuestos Cromogénicos , Diseño de Equipo , Fibroblastos/efectos de los fármacos , Colorantes Fluorescentes , Glioxal/farmacología , Humanos , Microscopía Fluorescente/instrumentación , Puntos Cuánticos
17.
Biosens Bioelectron ; 74: 1029-37, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26275712

RESUMEN

In this work, a novel approach that can calibrate the colors obtained with a cellphone camera was proposed for the colorimetric sensor array. The variations of ambient light conditions, imaging positions and even cellphone brands could all be compensated via taking the black and white backgrounds of the sensor array as references, thereby yielding accurate measurements. The proposed calibration approach was successfully applied to the detection of glucose in urine by a colorimetric sensor array. Snapshots of the glucose sensor array by a cellphone camera were calibrated by the proposed compensation method and the urine samples at different glucose concentrations were well discriminated with no confusion after a hierarchical clustering analysis.


Asunto(s)
Teléfono Celular , Colorimetría/instrumentación , Glucosa/análisis , Glucosuria/orina , Aplicaciones Móviles , Urinálisis/instrumentación , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/normas , Calibración/normas , Colorimetría/normas , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Urinálisis/normas
18.
Biomaterials ; 30(15): 2912-8, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19251316

RESUMEN

HER2 detection is important for breast cancer (BC) treatment and prognosis, but the detection methods currently used have some disadvantages. Quantum dots (QDs)-based probes provide a potentially important new method for HER2 detection in clinical practice. This potential is examined in this paper. A QDs HER2 probe kit and QDs image acquisition and analysis software were developed and applied to 94 clinical samples of BC. Compared to conventional immunohistochemistry techniques, this method provided a superior accurate and sensitive method for the detection of HER2 in clinical breast cancer diagnosis.


Asunto(s)
Neoplasias de la Mama/genética , Genes erbB-2 , Puntos Cuánticos , Estudios de Factibilidad , Técnica del Anticuerpo Fluorescente , Humanos , Sensibilidad y Especificidad
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