Abstract: Apparatus and methods are provided that enable the interaction of low-energy electrons and positrons with sample ions to facilitate electron capture dissociation (ECD) and positron capture dissociation (PCD), respectively, within multipole ion guide structures. It has recently been discovered that fragmentation of protonated ions of many biomolecules via ECD often proceeds along fragmentation pathways not accessed by other dissociation methods, leading to molecular structure information not otherwise easily obtainable. However, such analyses have been limited to expensive Fourier transform ion cyclotron resonance (FTICR) mass spectrometers; the implementation of ECD within commonly-used multipole ion guide structures is problematic due to the disturbing effects of RF fields within such devices.

Abstract: Encoded bead multiplex assays for chromosomal gains and losses are provided that provide the benefits of complex, large template DNA sources, such as BAC DNA, as the probe material without bead networking or other assay performance problems. Reagents for assaying DNA are described herein which include a plurality of encoded particles having attached amplicons amplified from a template DNA sequence. Each individual attached amplicon includes a nucleic acid sequence identical to a random portion of the template DNA sequence, wherein the amplicons together represent substantially the entire template DNA and wherein the nucleic acid sequence identical to a random portion of the template DNA sequence of each individual amplicon is shorter than the entire template DNA.

Abstract: A radioisotope labeled reagent includes a compound having the general formula (I), L-(aCbH2)naCbH3??(I) where a in each occurrence independently is a carbon mass number between 11 and 14 inclusive, b in each occurrence independently is a hydrogen mass number between 1 and 3 inclusive, such that a in each occurrence is not 12 simultaneously with b in each occurrence being 1; L is a leaving group R1SO2—O—, R1—S—, 12C1H3(12C3H2)n—S—R1C(O)O—, NC—, (R1)3P—, XMg—and Li—, where n is an integer between 0 and 3 inclusive, where X is chloro, bromo or iodine, where R1 is H, aryl, a substituent containing aryl, C1-C20 alkyl, a substituent containing C1-C20 alkyl, C2-C20 alkenyl, a substitute containing C2-C20 alkenyl, C2-C20 alkynyl, and a substitute containing C2-C20 alkynyl with the proviso that when n is 0, a is 13 and b is 2 and R1 in R1—S is not aryl.