High sensitivity radiation detector for capillary electrophoresis

Capillary electrophoresis (CE) is an instrumental technique capable of high resolution separation and analysis of small quantities of nucleotides, amino acids, peptides, and proteins with very high efficiency and throughput. The unprecedented sensitivity of this technique will be useful for such new applications as in vivo labeling and identification of trace substances and single cell work. The principal limitation of this technique for radiolabeled molecules has been identified as the sensitivity of the detector, primarily due to the small sample volume (<1 nl) and the short residence time of the sample in the detector (<3 sec). The authors report the development of a high-sensitivity CdTe solid-state detector used for detection of ³²P-labeled biomolecules with unprecedented sensitivity. This detector can be easily retrofitted into existing CE apparatus