Differential detection

Recently, the state-selective detection of reaction products tluough infrared absorption on vibrational transitions has been achieved and applied to the study of HF products from the F + H2 reaction by Nesbitt and co-workers (Chapman et al [7]). The relatively low sensitivity for direct absorption has been circumvented by the use of a multi-pass absorption arrangement with a narrow-band tunable infrared laser and dual beam differential detection of the incident and transmission beams on matched detectors. A particular advantage of probing the products tluough absorption is that the absolute concentration of the product molecules in a given vibration-rotation state can be detenuined. 

Bluhm, B. H., Flaherty, J. E., Cousin, M. A., and Woloshuk, C. P. (2002). Multiplex Polymerase Chain Reaction assay for the differential detection of trichothecene- and fumonisin-producing species of Fusarium in cornmeal. /. Food Prot. 65,1955-1961. 

Fig. 2. A magnetooptical player (2). P = polarizer MC = magnetic coil (for magnetooptical writing) NBS = neutral beam splitter PBS = polarizing beam splitter. Dl, D2 = detectors for differential detection. The optical path also comprises tracking and focusing optics which are not shown here.

To further extend the utility of CPMV virions as tools in nanobiotechnology, it was shown that CPMV particles can be utilized as building blocks for the construction of monolayer, bilayer, and multilayer arrays on surfaces in a controlled manner [109]. CPMV virions were labeled with two different ligands fluorescent dyes that enabled differential detection, and biotin molecules that allowed the... 

Medium resolution Semi-quantitative Differential expression Detects PTMs Medium resolution Semi-quantitative Improved differential Detects PTMs Low resolution Rapid profiling biofluids Signatures Small sample size Immunoaffinity separation Rapid multiplex analysis Immunoaffinity protein ID Small sample size... 

The Separation of a Mixture of Tetracyclines Monitored by Differential Detection... 

Dedysh S. N., Dunfield P. F., Derakshani M., Stubner S., Heyer J., and Liesack W. (2003) Differential detection of type II methanotrophic bacteria in acidic peatlands using newly developed I6S rRNA-targeted fluorescent oligonucleotide probes. FEMS Microbiol. Ecol. 43, 299-308. 

A typical example is the analysis of nitrate and chlorate. With the exception of the IonPac AS9 (Dionex Corp.), these ions cannot be separated on conventional anion exchangers, making misinterpretation of the chromatogram possible. The only way to distinguish between nitrate and chlorate is to make use of their different absorption characteristics chlorate is UV-transparent while nitrate can be detected at a wavelength of 215 nm. If both species are present in solution, determinations will only be possible via differential detection. 

At the present time there are no rapid lower tier , i.e., nonmammalian screening systems which have been validated as capable of detecting teratogenic substances. The basic problem is that an applicable screening test must differentially detect substances to which the conceptus is uniquely susceptible . Virtually any toxic substance is capable of affecting the fetus at doses that are close to those which are toxic to the adult, but such coeffective teratogens would not necessarily pose a developmental hazard. 

R. A. Leach, J. R0ii6ka, and J. M. Harris, Spectrophotometric Determination of Metals at Trace Levels by Flow Injection and Series Differential Detection. Anal. Chem., 55 (1983) 1669. 

Refractive index detectors are bulk property detectors with a near universal response, albeit limited by poor sample detectability for some applications [101 -106]. Differential detection is employed to minimize background noise with the result that the detector response is in some way related to the difference in refractive indices of the mobile phase and the mobile phase containing the sample. Consequently, an analyte will be detected only if its refractive index is different from that of the mobile phase. Peaks in both a positive and negative direction may be observed in the same chromatogram depending on whether the analyte has a higher or lower refractive index than that of... 

Improvements in these different techniques may come from either improved diodes or detection schemes. The nonlinearities measured in the current-VOItage curves of our MIM diodes are extremely small and conversion efficiencies could be 100 times larger. We are optimistic that better materials which will result in larger FIR powers may be found. Differential detection schemes would also significantly improve the sensitivity and permit the detection of weaker lines. The sensitivity, however, is still only about 1% of that of laser magnetic resonance. Laser magnetic resonance is useful only for paramagnetic... 

Simpson, J. A., R. Labugger, G. G. Hesketh, C. D Arsigny, D. O Donnell, N. Matsumoto, C. P. Collier, S. Iscoe, and J. E. Van Eyk (2002). Differential detection of skeletal troponin I isoforms in serum of a patient with rhabdomyolysis markers of muscle injury Clin Chem 48(7) 1112-1114. 

Here I a and Ip are the fluorescence intensities of the donor and acceptor respectively (for the same doubly labelled molecule), 4>a and Op are the quantum yields of the donor and acceptor molecules and and rjp are the detection efficiencies of the experiment at the wavelengths of the fluorescence signals from the two molecules. For simplicity, the correction factor, y, to account for differential detection efficiencies and quantum yields of the two fluorophores is generally assumed to be unity (see for a discussion [78]), and fret is then sometimes referred to as the proximity ratio P [ 77]. 

Fluorescent Staining. Certain methods of tissue staining differentially detect the presence of particular chemical components in cells. One approach is to use a fluorescent label to trace components inside the cell. Fluorescent staining not only attests to the presence or absence of certain components in cells but also provides their precise localization in a particular cell or tissue type. For example, immunochem-istry uses fluorescent antibodies that specifically bind with the target structures in the tissue so that the labeled antibodies will highlight the presence of the structures of interest in the analyzed specimen. Some applications of these techniques are staining of virus-infected cells in tissues and detection of immune-complex deposition in the kidneys and skin of patients with lupus. 

Similarly as in the GB case, the absorption maximum of GD is at 9P -band. The absorption at other transmission lines of CO2 laser are very low, therefore is possible to use these lines as reference only. A maximum of absorption can be estimated from the common mfrared absorption spectrum of GD, Fig. 2 The absorption maximum is at wavelaigth of 9.8367 mm. The working pair for differential detection has been selected at line 9P38 as measure and 10 4 line as reference. 

D. M. Alperin, H. Carminatti, V. Idoyaga-Vargas, and R. O. Couso, Thermal-ultra-violet method for differential detection and recovery of organic compounds in thin-layer chromatography, J. Chromatogr. 265 193-200(1983). 

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