Oligonucleotides detectors

Oligonucleotide arrays [6] In-situ on the surface of the matrix 1 cm by 1 cm slide with approximately 40 000 genes Affymetrix s GeneChip can contain up to 400 000 different oligonucleotides and is the densest array Fluorescent tag labeling fluorophore detector is added after hybridization Passive Affymetrix... 

Other methods of detection of hybridisation event consist of the use of labels. These labels can be divided into electroactive and enzymatic labels. The schemes commonly used for detection are scheme b or c. The scheme selected to detect the hybridisation event depends on whether the target is labelled with a marker by PCR amplification or using a labelling kit, or whether a labelled synthetic detector oligonucleotide is used. These methods are usually the most sensitive, but the need of a labelling step makes them more complex, tedious and... 

An on-column contact conductivity detector was fabricated on a PMMA chip to analyze amino acids, peptides, proteins, and oligonucleotides. To minimize faradaic reaction and to only measure ohmic resistance (or conductivity), a bipo-... 

Leclerc [3] prepared regioregular and water soluble polythiophenes by oxidizing thiophene derivatives with iron (HI) chloride which were then used as optical and electrochemical detectors of double-stranded oligonucleotides. 

Oligonucleotides have a broad absorption band around 260 nm where the extinction coefficient is such that a solution of 30 /rg/ml in a 10 mm cell gives an absorbance of the order of 1 (10% transmission). Wavelengths of 254 and 265 nm are not much worse but at 280 nm the extinction coefficient is about half that at 260 nm. This makes ultraviolet monitors working near 260 nm rather sensitive detectors of oligonucleotides and they are widely used in this field. 

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