Multiple detection

Demonstrate that the system includes controls to detect multiple attempts at unauthorized use (e.g., repeated login attempts/failed password entry on login and electronic signature). 

Non-NADA methods may be designed to detect multiple residues and they may be designed for use in multiple species. In order to validate these multi-residue methods, modifications to the validation protocol relative to single analyte methods are made. Additional laboratories will participate in the method trial, but the number of samples... 

Ulerich, N. H., and Powers, G. J., On-Line hazard aversion and fault detection Multiple loop control example. AIChE Fall National Meeting, New York, 1987. 

Taitt C.R., Golden J.P., Shubin Y.S., Shriver-Lake L.C., Sapsford K.E., Rasooly A., Ligler F.S. A portable array biosensor for detecting multiple analytes in complex samples, J. Microbiol. Ecol. 2003 Feb 9. 

Selection of on-site analytical techniques involves evaluation of many factors including the specific objectives of this work. Numerous instrumental techniques, GC, GC-MS, GC-MS-TEA, HPLC, HPLC-MS-MS, IR, FTIR, Raman, GC-FTIR, NMR, IMS, HPLC-UV-IMS, TOF, IC, CE, etc., have been employed for their laboratory-based determination. Most, however, do not meet on-site analysis criteria, (i.e., are not transportable or truly field portable, are incapable of analyzing the entire suite of analytes, cannot detect multiple analytes compounded with environmental constituents, or have low selectivity and sensitivity). Therefore, there exists no single technique that can detect all the compounds and there are only a few techniques exist that can be fielded. The most favored, portable, hand-held instrumental technique is ion mobility spectrometry (IMS), but limitations in that only a small subset of compounds, the inherent difficulty with numerous false positives (e.g., diesel fumes, etc.), and the length of time it takes to clear the IMS back to background are just two of its many drawbacks. 

There has been considerable interest in using fluorescence anisotropy to detect multiple environments in membranes as with fluorescence lifetimes (see above). For example, if a fluorophore is located in two environments with long and short lifetimes, then the fluorescence anisotropy decay process at longer times after excitation will be dominated by the long-lived fluorescent species. This occurs with parinaric acids, and this situation has been explored for a number of theoretical cases. 60 A similar situation has been found for DPH in two-phase lipid systems by collecting anisotropy decay-associated spectra at early and late times after excitation. 61 Evidence was found for more than one rotational environment in vesicles of a single lipid of it is at the phase transition temperature. It is important to identify systems showing associated anisotropy decays with more than one correlation time, each of... 

Interpretation of molecular spectra involves four basic steps. First, major skeletal and functional group components of the molecule are identified, either from assumptions about the compound origin or from features of the spectra. Second, non-localized molecular properties such as the molecular weight, elemental composition, and chromatographic behavior are considered. These global constraints can be used to eliminate unlikely functional groups, deduce the presence of groups and skeletal units which have no distinctive features in the spectra, and detect multiple occurrences of... 

Another application of this methodology is to use several different copolymers to detect multiple analytes in a single sample. Each polymer would have a different antibody attached and be precipitated at a different temperature. This appears to be possible since one copolymer that precipitates at a lower temperature does not appear to remove a copolymer with a higher LCST from solution. (J. H. Priest, unpublished observations). It is also conceivable that a DNA probe-based assay could be included with a panel of immunoassays. After removal of the various antibody-copolymer conjugates at lower temperature sodium chloride would be added, the hybridization would be performed at 55 C and the DNA-copolymer conjugates precipitated at 65 C. 

On examination of the urine and serum of numerous patients with suspected paraproteinemia in both Jamaicans and Africans between 1962 and 1966, it was concluded that whenever a low total serum y-globulin level with a normal serum electrophoretic pattern were encountered in a suspected case of multiple myelomatosis, it was then essential to obtain also a specimen of urine from such a patient for further electrophoretic examination. Invariably simultaneous electrophoresis of such sera and urines proved to be diagnostic, even when the classical heat test for Bence Jones protein was negative. Consequently it was found that concurrent electrophoresis of scrum and urine was the first means of detecting multiple myelomatosis in no less than 20% of the patients, which were subsequently confirmed either by bone marrow biopsy or X-ray examination or both (M3). 

HMBC ( -Detected Multiple-bond Heteronuclear Multiple Quantum Coherence Spectrum) NMR of 26a allowed one to show that the isopropyl group (Ha, Hfc) is connected to the olefmic carbon (Cc), whereas methyl (IF) and methylene (H-C, H- ) groups are bonded to another olefmic carbon (Cd) and fullerene carbon (Ch) through quaternary carbon (Ce) shown in 26a and 26b (Scheme 8). 

Great progress was made by Marzilli143 on using -detected multiple-quantum NMR, in the structure determination of d(TGGT). 

Steffen, W. and Linck, R. W. (1989) Multiple immunoblot a sensitive technique to stain proteins and detect multiple antigens on a single two-dimensional replica. Electrophoresis 10,714—718. 

The use of X-ray microscopy to image chemical signals in biological materials requires probes that can be applied to both naturally occurring and artificially introduced molecules, particularly proteins. Current capabilities allow for only a single molecular species of protein inside a cell to be imaged. There is a need to develop the capability to simultaneously detect multiple proteins inside the cell... 

Fluorescence may by induced using labeled mono- or polyclonal antibodies raised against the compound of interest. This technique has been used successfully to detect the presence of okadaic acid in cultures of Prorocentrum lima, and, further, to estimate quantities of the compound in individual cells.110 Immunofluoresence in combination with thin layer chromatography and ELISA techniques have also been used to detect multiple haptens in mycotoxin families.111112... 

Kwok, Y.C., Manz, A., Shah convolution Fourier transform detection multiple-sample injection technique. Electrophoresis 2001, 22, 222-229. 

Taking advantage of the ability to detect multiple group II and group III metals at mercury film electrodes using stripping analysis, a multianalyte DNA sensor was developed using different semiconductor nanocrystals (ZnS, CdS, and PbS) for the... 

More recent trends aim in the direction of fabricating electrochemical protein array systems (for detecting multiple protein targets) and miniaturization of such immunoassays. These include an electrochemical protein chip with an array of 36 platinum electrodes on a glass substrate (64) and electrical immunoassays using microcavity formats down to the zmol antigen level (65). 

Rice endosperm ADPGlc PPase has been purified to apparent homogeneity (43 U/ mg).153 However, electrophoretic analyses detected multiple isoforms, and no kinetic characterization was reported. However another report shows that the purified endosperm ADPGlc PPase is activated by 3PGA (40-fold) and inhibited by Pi.81 The allosteric kinetic constants are given in Table 4.1. 

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