管理提醒: 本帖被 chenshuuu 执行加亮操作(2010-12-27)
all-molecule-binding nucleic acids conjugated to graphene oxide improve extraction and ionization of ytes from biological samples, an international research team has discovered (J. Am. Chem. Soc., DOI: 10.1021/ja109042w). Weihong Tan of the University of Florida and coworkers at Stanford University and China’s Hunan University attach aptamers—single-stranded oligonucleotides that bind target molecules with high affinity—to the surface of graphene oxide via a flexible poly(ethylene glycol) linker. The linker stabilizes the construct in biological fluids and allows the aptamers to fold into their three-dimensional conformations. The researchers used graphene oxide modified with a e-binding aptamer to extract e from spiked plaa samples and then yzed the drug by mass spectrometry directly from the graphene oxide surface. With unmodified graphene oxide, Tan and colleagues observed a signal-to-noise (S/N) ratio of about 15 in the mass ysis. The aptamer-modified graphene oxide efficiently captured the e and boosted the S/N ratio to an average of 52. The researchers achieved similar improvements with graphene oxide attached to an adenosine-binding aptamer.