Biological probes detectability

In the context of molecular biology, probes may be described as molecules whose recognition capability allows for the detection of specific target molecules. 

Biological Applications Detecting FRET in cells monitoring fast neuronal activity and signaling quantifying plasma membrane expression cytotoxicity assay membrane fusion assay probe for endocyto-sis probe for exocytosis ... 

Biological Applications Detecting nucleic acids lipid probes measuring collagenase, target nucleic acid sequence fluorescent immunoassays ... 

Despite the capabilities of quinoline-based probes for selective detection of Cd ", these probes have limited applicability for optical imaging of biological samples due to the requirement for ultraviolet excitation (7,ex < 330 nm), which is deleterious to biological samples and induces autofluorescence from endogenous cellular molecules such as NADH and FAD. Furthermore, the fluorescence properties of quinoline fluorophores generally depend on the solvent polarity, which may make them unsuitable for biological Cd " detection. 

In this section, we describe theoretical methods that describe the macroscopic optical properties of metal nanoparticles (a.k.a quantum dots). Recently, silver and gold nanoparticles have foimd tremendous use in biological assays, detection, labelling and sensing because of their sensitive optical spectra. While some works in the literature refer to these as quantum dots , in optical absorption experiments their quantized energy structure is not probed. The spectrum is a probe of the localized surface plasmon phenomenon, a collective electronic excitation that is localized in spatial extent owing to the small size of the nanoparticle compared with the wavelength. 

Southern, E. M., 1975. Detection of specific sequences among DNA fragments separated by gel electrophoresis. Journal of Molecular Biology 98 503-517. The classic paper on die idendficadon of specific DNA sequences through hybridizadon widi unique probes. 

The power of the pooled GST fusion protein approach will increase as new biochemical reagents and assays become available. The development of chemical probes for biological processes, termed chemical biology, is a rapidly advancing field. For example, the chemical synthesis of an active site directed probe for identification of members of the serine hydrolase enzyme family has recently been described (Liu et al., 1999). The activity of the probe is based on the potent and irreversible inhibition of serine hydrolases by fluorophosphate (FP) derivatives such as diisopropyl fluorophosphate. The probe consists of a biotinylated long-chain fluorophosphonate, called FP-biotin (Liu et al., 1999). The FP-biotin was tested on crude tissue extracts from various organs of the rat. These experiments showed that the reagent can react with numerous serine hydrolases in crude extracts and can detect enzymes at subnanomolar... 

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