Micro detection

The potentiometric micro detection of all aminophenol isomers can be done by titration in two-phase chloroform-water medium (100), or by reaction with iodates or periodates, and the back-titration of excess unreacted compound using a silver amalgam and SCE electrode combination (101). Microamounts of 2-aminophenol can be detected by potentiometric titration with cupric ions using a copper-ion-selective electrode the 3- and... 

FIGURE 2 Schematic diagram of the Millipore MicroStar microbial enumeration system. The cells are concentrated by membrane filtration and the membrane filter is positioned at the top of the detection tower (upper left). CCD, charge-coupled device RMDS, rapid micro detection system. (Courtesy of Millipore Corp.)... 

Crouch, R.C., G.E. Martin, R.W. Dickey, and D.G. Baden (1995). Assignment of the IH and 13C NMR spectra of complex natural products and the submilligram level using micro detection probes— Brevetoxin-3 (PbTx-3). Tetrahedron 51, 8409-8422. 

Heydorn, K. Detecting Errors in Micro and Trace Analysis by Using Statistics, Anal. Chim. Acta 1993, 283, 494M99. 

Unlike the array collector, with a microchannel plate all ions of only one m/z value are detected simultaneously, and instrument resolution does not depend on the number of elements in the micro-channel array or on the separation of one element from another. For a microchannel plate, resolution of m/z values in an ion beam depends on their being separated in time by the analyzer so that their times of arrival at the plate differ. 

Thin-Layer Chromatography (tic). Tic (126) is used widely for quahtative analysis and micro-quantity separation of amino acid mixtures. The amino acids detected are developed by ninhydrin coloring, except for proline and hydroxyproline. Isatia has been recommended for specific coloring of pToline (127). 

In field testing, there are many commercial products and instmments available that ate helphil in rapidly detecting, identifying, and quantifying micro organisms. 

MICRO ELECTRO-MECHANICAL SYSTEMS FOR THE DETECTION OF BIOANALYTES USING ELECTROCHEMILUMINESCENCE... 

A method of detecting herbicides is proposed the photosynthetic herbicides act by binding to Photosystem II (PS II), a multiunit chlorophyll-protein complex which plays a vital role in photosynthesis. The inhibition of PS II causes a reduced photoinduced production of hydrogen peroxide, which can be measured by a chemiluminescence reaction with luminol and the enzyme horseradish peroxidase (HRP). The sensing device proposed combines the production and detection of hydrogen peroxide in a single flow assay by combining all the individual steps in a compact, portable device that utilises micro-fluidic components. 

Isolation of Citronellal and Citral. At the close of each experiment (7 to 10 days), the nests were frozen intact. Groups of 200 workers were placed in a micro-Soxhlet apparatus and extracted for 8 hours with methylene chloride. A few milligrams of carrier citronellal and citral were added and the mixture was applied to a thin-layer chromatoplate (silica gel G) which was developed with hexane-ethyl acetate (92 to 8) to separate citronellal and citral (3). The aldehydes were detected by spraying with a solution of 2, 4-dini-trophenylhydrazine in tetrahydrofuran (20) and the citronellal and citral peaks were scraped off and allowed to react with excess dinitro-phenylhydrazine reagent for a further 12 hours. 

---