Interesting work on ProTx-II from the University College of London. ProTx-II is a potent blocker of the voltage-gated sodium channel Nav1.7. Results show that the synthetic Smartox’ ProTx-II is highly active.
View results here: http://discovery.ucl.ac.uk/1467249/1/Zoe%20Wright%20PhD%20Thesis.pdf
ProTx-II is also available with a fluorescent and a biotin tag.