Detection and analysis

Radiochemical tracers, compounds labeled with radioisotopes (qv), have become one of the most powerful tools for detection and analysis in research, and to a limited extent in clinical diagnosis (see Medical IMAGING TECHNOLOGY). A molecule or chemical is labeled using a radioisotope either by substituting a radioactive atom for a corresponding stable atom in the compound, such as substituting for H, for or for P, and for for... 

The detection and analysis, including quantification, of cyanobacterial toxins are essential for monitoring their occurrence in natural and controlled waters used for agricultural purposes, potable supplies, recreation and aquaculture. Risk assessment of the cyanobacterial toxins for the protection of human and animal health, and fundamental research, are also dependent on efficient methods of detection and analysis. In this article we discuss the methods developed and used to detect and analyse cyanobacterial toxins in bloom and scum material, water and animal/clinical specimens, and the progress being made in the risk assessment of the toxins. 

Methods for the detection and analysis of cyanobacterial toxins fall into two... 

A number of studies (Kristoff and Guilbault 1983 Milanko et al. 1992) have investigated the use of coated and uncoated piezoelectric crystals in the detection and analysis of diisopropyl methylphosphonate in air samples. Piezoelectric crystals have a natural resonant frequency of oscillation that can be utilized to detect... 

Cutillas, P.R., Norden, A.G., Cramer, R., Burlingame, A.L., Unwin, RJ. (2003). Detection and analysis of urinary peptides by on-line liquid chromatography and mass spectrometry application to patients with renal Fanconi syndrome. Clin. Sci. (Lond.) 104, 483 490. 

The ProteinChip System from Ciphergen Biosystems uses patented SELDI (Surface-Enhanced Laser Desorption/Ionization) ProteinChip technology to rapidly perform the separation, detection, and analysis of proteins at the femtomole level directly from biological samples. ProteinChip Systems use ProteinChip Arrays which contain chemically (cationic, anionic, hydrophobic, hydrophilic, etc.) or biochemically (antibody, receptor, DNA, etc.) treated surfaces for specific interaction with proteins of interest. Selected washes create on-chip, high-resolution protein maps. This protein mass profile, or reten-tate map of the proteins bound to each of the ProteinChip Array surfaces, is quantitatively detected in minutes by the ProteinChip Reader. 

Phizicky, E.M., and Fields, S. (1995) Protein-protein interactions Methods for detection and analysis. Microbiol. Rev. 59, 94-123. 

In fuel-lean premixed burners, the primary air ratio determines the quality of combustion changing the rotational speed of the flue gas fan has also some influence. An ionization probe is used to determine the quality of combustion. A dedicated system, developed at GWI, provides accurate detection and analysis of the ionization signal. This includes a metering device, which is provided with a rectangular supply voltage, thus warranting very accurate ionization signals. 

The alternative approach to detection and analysis incorporates a solid state detector and a multichannel pulse height analysis system. The crystals used are of silicon (of the highly pure intrinsic type), or the lithium drift principle (p. 463 etseq.) is utilized. All emitted radiations are presented to the detector simultaneously and a spectrum is generated from an electronic analysis of the mixture of voltage pulses produced. Chapter 10 contains a more detailed account of pulse height analysis and solid state detectors. Production of an X-ray spectrum in this way is sometimes known as energy dispersive analysis ofX-rays (EDAX) and where an electron microscope is employed as SEM-EDAX. 

Scintillation counters, which constitute an extremely important group, depend upon the absorption of radiation by a scintillator to produce UV light scintillations, which are detected and converted into amplified voltage pulses by a photomultiplier (Figure 10.10). Solid scintillators are used extensively for the detection and analysis ofy-rays and X-rays, while liquid scintillators find widespread employment in the measurement of pure negatron emitters, especially where the particle energy is low (< 1 MeV). 

Flurkey WH. Polyphenoloxidase in higher plants immunological detection and analysis of in vitro translation products. Plant Physiol 1986 86 614-618. 

Electrical methods involve the detection and analysis of electronic pulses generated by droplets in a measurement volume or on a wire. The electronic signals are then converted into digital data and calibrated to produce information on droplet size distribution. A detailed review of electrical methods for droplet size measurements has been made by Jones.[657]... 

To minimize problems with the detection and analysis of a gene that exists as a single copy on an autosomal chromosome, technology of extreme sensitivity needs to be employed. Although the standard Southern analysis combines reasonable sensitivity with greater specificity, it is labor-intensive, requiring the use of radioisotopes such as 32P, and a few days are required to complete an analysis. Several pitfalls of the Southern procedure can be eliminated by substituting the PCR technique (M4). 

Henikoff, S., and Henikoff, J. G. (2000). Protein family-based methods for homology detection and analysis. In Bioinformatics, A Practical Approach. (D. Higgins, and W. Taylor, eds.), IRL Press, (In press). 

Some PAHs (e.g., phenanthrene, pyrene, and benzo[g,/z,i]perylene) are commonly seen in products boiling in the middle to heavy distillate range. In a method for their detection and analysis (EPA 8310), an octadecyl column and an aqueous acetonitrile mobile phase are used. Analytes are excited at 280 nm and detected at emission wavelengths of >389 nm. Naphthalene, acenaphthene, and fluorene must be detected by a less sensitive UV detector because they emit light at wavelengths below 389 nm. Acenaphthylene is also detected by UV detector. 

Numerous workers have demonstrated the applicability of electrospray ionization mass spectrometry (ESI/MS) for the detection and analysis of biomolecules with highly electronegative groups (reviewed by Wood et al., 2003, and for neutral steroids by Higashi and Shimada, 2004). The sensitivity of detection of neurosteroids can also be enhanced by derivatization when they are analyzed by nano-electrospray/mass spectrometry procedures. Neurosteroid sulfates can be easily prepared in a single-step reaction in pyridine with the N,N-dimethylformamide complex of sulfur trioxide (Chatman et al., 1999). Another elegant... 

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