SmartFlare controversy: independent confirmation of endosomal localization

Check this previous post for a quick summary of the SmartFlare controversy, or read all SmartFlare-related posts if you are really passionate. At the centre of the SmartFlare controversy is the rather simple question, from an experimental point of view, of how many Spherical Nucleic Acids (to use Chad Mirkin’s terminology), if any, escape the […]

How many people are using the #SmartFlares? Freedom of Information request provide insights

Quick summary of previous episodes for those who have not been following the saga: Chad Mirkin’s group developed a few years ago a technology to detect mRNAs in live cells, the nano-flares. That technology is currently commercialised by Merck under the name smartflares. For a number of reasons (detailed here), I was unconvinced by the […]

SmartFlare Maths

SmartFlare are nanoparticle sensors which are sold by Merck and are supposed to detect mRNA inside live cells. The technology has been developed by Chad Mirkin. In his papers, the nanoparticles are called Nano-Flares or Spherical Nucleic Acids. I am saying “supposed to” because the central question of how those sensors could possibly reach the […]

Lab Times: “Flare up over SmartFlares”

Stephen Buckingham interviewed me for Lab Times On the face of it, Millipore’s SmartFlares are meant to be a tool cell biologists dream of – a way of measuring levels of specific RNA in real time in living cells. But does it really work? Raphaël Lévy and Gal Haimovich are in doubt. Raphaël Lévy, Senior […]

Do nanoparticles deliver? Merck’s SmartFlares and other controversies

Originally posted on For Better Science:
A large body of scientific nanotechnology literature is dedicated to the biomedical aspect of nanoparticle delivery into cells and tissues. The functionalization of the nanoparticle surface is designed to insure their specificity at targeting only a certain type of cells, such as cancers cells. Other technological approaches aim at…

New data on SmartFlare – do they detect mRNA?

Originally posted on greenfluorescentblog:
Almost exactly a year ago, I wrote a post regarding my concerns with SmartFlare, supposedly a novel method for live imaging of RNA in cells. In a nutshell, SmartFlare are gold nanoparticles covered in oligos specific to a certain mRNA of interest. Supposedly, cells internalize these particles and, once the mRNA…

Are StickyFlares smarter than SmartFlares?

Update (19/08/2015): Dave Mason has posted a detailed critique of this paper at PubPeer Update (19/10/2015): We have submitted a response to this paper as a Letter to the Editor of PNAS. It is currently available as a preprint. Update (16/11/2015): Inder Verma, Editor of PNAS, has decided that our letter “does not contribute significantly […]

How smart are SmartFlares?

This post is co-authored by Raphaël Lévy and Dave Mason. Note: We contacted Chad Mirkin and EMD Millipore for comments. Chad Mirkin replied but did not allow me to share his comments as he prefers to discuss his work in peer reviewed manuscripts rather than blogs. EMD Millipore has provided a response (reproduced below) and is keen to further engage in […]


Some readers might wonder why I am going on about this, so let me tell you: this is a considerably more important story than Stripy Nanoparticles Revisited. If, as I am arguing, some of this science is shaky, then it is not only the way we evaluate scientists and spend public money which are put into […]

A response from Chad Mirkin’s group

Well nearly. Possibly as close as we might get. If you have followed the Spherical Nucleic Acid / SmartFlare / StickyFlare story on this blog, you will know that we have raised doubts about the endosomal escape of these nanoparticles which are supposed to reach the cytosol of cells where they could detect mRNAs. We […]