文献 | 量子荧光|微型光纤光谱仪-ag贵宾会

a new strategy is proposed for determination of carcino-embryonic antigen (cea) based on aptamer/ graphene oxide(apt/go) by capillary electrophoresis-chemiluminescence(ce-cl) detection system. cea aptamer conjugated with horseradish peroxidase(hrp) firstly mixes with go,and the cl willbe quenched because the stack of hrp–apt on go leads to chemiluminescence resonance energy transfer (cret). when cea exists, the specific combination of hrp–apt and cea can form hrp–apt–cea complex, which dissociates from go. then, the cl catalyzed by hrp–apt–cea complex can be detected without any cret, and the content of cea can be estimated by the clintensity. it has been proved that the interference issue resulted from free hrp–apt issolved well by mixing go firstly with hrp–apt, which blocks the free hrp–apt's cl signal due to cl quenching effect of go; and the interference resulted from go to cl is also solved by ce, then the sensitivity and accuracy can be greatly improved. results also showed that the cl intensity had a linear relationship with the concentration of cea in the range from 0.0654 to 6.54ng/ml, and the limit of detection was approximately 4.8pg/ml(s/n?3). this proposed method with high specificity offers a new way for separation and determination of biomolecule, and has good potential in application of biochemistry and bioanalysis.

clinical diagnostic devices provide new sources of information that give insight about the state of health which can then be used to manage patient care. these tools can be as simple as an otoscope to better visualize the ear canal or as complex as a wireless capsule endoscope to monitor the gastrointestinal tract. it is with tools such as these that medical practitioners can determine when a patient is healthy and to make an appropriate diagnosis when he/she is not. the goal of diagnostic medicine then is to efficiently determine the presence and cause of disease in order to provide the most appropriate intervention. the earliest form of medical diagnostics relied on the eye – direct visual observation of the interaction of light with the sample. this technique was espoused by hippocrates in his 5th century bce work epidemics, in which the pallor of a patient’s skin and the coloring of the bodily fluids could be indicative of health. in the last hundred years, medical diagnosis has moved from relying on visual inspection to relying on numerous technological tools that are based on various types of interaction of the sample with different types of energy – light, ultrasound, radio waves, x-rays etc. modern advances in science and technology have depended on enhancing technologies for the detection of these interactions for improved visualization of human health. optical methods have been focused on providing this information in the micron to millimeter scale while ultrasound, x-ray, and radio waves have been key in aiding in the millimeter to centimeter scale. while a few optical technologies have achieved the status of medical instruments, many remain in the research and development phase despite persistent efforts by many researchers in the translation of these methods for clinical care. of these, raman spectroscopy has been described as a sensitive method that can provide biochemical information about tissue state while maintaining the capability of delivering this information in real-time, non-invasively, and in an automated manner. this review presents the various instrumentation considerations relevant to the clinical implementation of raman spectroscopy and reviews a subset of interesting applications that have successfully demonstrated the efficacy of this technique for clinical diagnostics and monitoring in large (n z 50) in vivo human studies.

for almost a century, the iridescence of tropical morpho butterfly scales has been known to originate from 3d vertical ridge structures of stacked periodic layers of cuticle separated by air gaps. here we describe a biological pattern of surface functionality that we have found in these photonic structures. this pattern is a gradient of surface polarity of the ridge structures that runs from their polar tops to their less-polar bottoms. this finding shows a biological pattern design that could stimulate numerous technological applications ranging from photonic security tags to selfcleaning surfaces, gas separators, protective clothing, sensors, and many others. as an important first step, this biomaterial property and our knowledge of its basis has allowed us to unveil a general mechanism of selective vapor response observed in the photonic morpho nanostructures. this mechanism of selective vapor response brings a multivariable perspective for sensing, where selectivity is achieved within a single chemically graded nanostructured sensing unit, rather than from an array of separate sensors.

we report the detection of characteristic raman lines for several chemicals using a single-beam coherent anti-stokes raman scattering (cars) technique from a 12 meter standoff distance. single laser shot spectra are obtained with sufficient signal to noise ratio to allow molecular identification. background and spectroscopic discrimination are achieved through binary phase pulse shaping for optimal excitation of a single vibrational mode. these results provide a promising approach to standoff detection of chemicals, hazardous contaminants, and explosives.