Nat. Protoc. 1, 387–396 (2006); doi:10.1038/nprot.2006.59; published online 27 June 2006; corrected after print 5 August 2015

In the version of this article initially published, Figure 1 contained the words “metoxyamin hydrochloride.” These words should have read “methoxyamine hydrochloride.” The error has been corrected in the HTML and PDF versions of the article.