Shine On You Deadly Bacteria

As I mentioned in a previous post, I've been working with a small research team on the development of an electrochemical sensor to detect pathogenic E. coli bacteria. I've already discussed the difficulty that I had in obtaining an accurate cell count to quantify the concentration of the E. coli cells in the soy broth suspension that they live in. Well, I've overcome the problems that I was having with cell counting and have moved on to fluorescent imaging of the cells. More specifically, I've been charged with labeling the E. coli with a fluorescent dye and exposing the labeled cells to our electrochemical devices functionalized with IgG antibodies that selectively bind to E. coli. Then, rather than taking electrochemical measurements, I want to take fluorescent images to correlate our findings from the sensor data to actual images of the cells bound to the device.

I've been working on fluorescently labeling the E. coli cells with fluorescein isothiocyanate (FITC) for a couple of months now, with essentially no success. FITC is an amine-reactive fluorophore, and so my plan was to label the anti-E. coli antibody with FITC, then allow the labeled antibodies to coat the surface of the cells. However, that didn't work out so well. After several attempts using this procedure, I ended up with zero observable or measurable fluorescence from the E. coli cells. I did learn some things along the way, though. Most notably, I learned that trying to label viable live cells is a fool's errand unless absolutely necessary, so I started heat killing the cells before the labeling procedure.

After these failed attempts, I decided to simplify things a bit. Why not try to label the E. coli with FITC directly, rather than trying to use the antibody as an intermediate? So that's what I did. I introduced the killed cells to a large concentration of FITC, allowed the binding reaction to take place for an hour or so, and then purified the labeled cells from the remaining free dye. The resulting solution of labeled E. coli showed strong fluorescence when analyzed using fluorescence spectroscopy, so I dropped the cell suspension on a microscope slide and took some fluorescent images. And...well...see for yourself:


Those small elongated dots are the brightly labeled rod-shaped bacteria. I should mention that, despite being stored in the dark, the fluorescent emission of the cells is dropping surprisingly quickly. I would guess that this may be an indication that rather than the expected covalent attachment of the FITC to surface proteins on the E. coli, the FITC diffused into the cell and is slowly diffusing back out again over time. Either way, the cells were initially nice and bright, which allowed me to take some good images of the labeled cells bound to our electrochemical sensor device, which is exactly what I needed to do.

Update: Not So Aww Crap After All?

I was disappointed that Spaceweather.com was not listing any ISS flybys for the next week, thinking that I had missed viewing it this time around. But on a whim, I decided to check out NASA's page with sighting schedules. What do you know? According to NASA, the ISS will be visible nearly everyday for the next two weeks.

I should mention, however, that most of the flybys will be very low, with maximum elevations in the teens or twenties. On the night of May 3rd, the ISS is scheduled to reach a maximum elevation of 67 degrees, though. That's pretty good. Also, on the next night, May4th, the sighting duration is scheduled to be longer: 4 minutes. That's pretty much the maximum amount of time that the ISS flyby ever lasts, since it moves so fast.

So get your binoculars out and happy ISS viewing to all!

Aww Crap!

It looks like Wired Science let me down this week.

The blog reported on an International Space Station flyby that has been taking place this week. This is a relatively rare event in which the ISS is not eclipsed by the planet as it makes its way overhead. I remember getting a good look at one of the recent ISS flybys a few years back, and it was pretty wild. During the flyby, the ISS is the brightest object in the night sky except for the moon. And it behaves unlike any other heavenly body. It moves startlingly fast, rising above the horizon and then setting at the opposite horizon, all within a matter of a few minutes.

The problem? Wired reported on the flyby on the afternoon of the last day that the ISS would be visible. And since I didn't see the post until this morning, I totally missed it! According to Spaceweather's satellite flyby database for my zip code (65203), the ISS was visible on the evenings of Monday April 18 and Tuesday April 19, with a magnitude of 'very bright.'

Oh well. I'll just have to do a better job of keeping up to date with Spaceweather. Hopefully the next time this happens, I'll be on top of it. And maybe we can have a big ISS flyby watch party. That would be awesome.

@Pharyngula: I'm In the Future Too! #itsnotsobad

I'm a little late in getting this out. But for any readers conducting high level research, albeit in academia, industry, or government, I can't recommend this post from Pharyngula enough. In fact, I not only recommend reading it, but I would also persuade you to absorb it via osmosis, respiration, hypodermic injection...whatever your preferred method of information delivery.

Here's the tale that Dr. Myers relates: a professor conducting research on genetics (this is a disturbingly gross simplification, but I'm going to leave it at that) published a paper in a high impact journal PLoS One. Rather than following standard operating procedure and sending out a traditional press release through the university, the professor posted a somewhat informal presentation of the paper on his blog.

This is an important event for a number of reasons, which Dr. Myers does a great job of discussing. But I would like to emphasize the point that the use of online media to reach a target audience is here to stay, and is only going to become more prevalent. As for myself, I recently published a paper in the journal Analytical Chemistry, and I was very proud of this achievement. When it was published, I linked to my paper and its selection as a featured article by the American Chemical Society on Facebook. I didn't do this because I thought it would be some kind of game-changing decision; I did it to brag about my success to my friends. But after reading the Pharyngula post, I can't help thinking that I could've taken the whole process farther. A lot farther.

Instead of directing my Facebook friends to the journal article, I could have posted an informal discussion of the article on this blog, linking to the journal article within the post. Then I could've directed my Facebook friends, Twitter followers, and LinkedIn connections to the blog post by updating my status or tweeting or whatever with a link to my blog. In this way, I would've reached many more people with a very easy and free way of utilizing the online networks of which I am already a part.

I should point out that I am not special in thinking this is a good idea. Others are already utilizing new media to reach out to their peers and share information more quickly and easily than ever before. Dr. Myers concludes his blog post by saying this:

Are any of your grad students and post-docs blogging? You might want to think about getting them trained in this brave new world now, before it's too late. And you might want to consider getting started yourself, if you aren't already.

I agree, Fearless Leader. I agree.

What The Hell is That?

Here's a little tidbit that might inject some intellectual titillation into your Monday morning (or whenever you happen to be reading this):

Via Wired Science, an unknown cosmic phenomenon is being observed. The astronomical blast, which is emitting large amount of electromagnetic radiation aimed in our general direction, is puzzling NASA researchers. Initially, it was thought to be a gamma ray burst. A gamma ray burst is a directional expulsion of energetic gamma rays associated with the collapse of a massive star. But gamma ray bursts normally only last for a matter of seconds, while the blast in question has now lasted for 11 days. And equally bizarre is how the event has been behaving over those 11 days, with the radiation fading and brightening and emitting sudden pulses.

Check out the original post for more information on this wild event and to read up on what researchers believe the blast might be.

How To: Destroy a Planet Part II

As a regular reader of Paul Krugman's blog and NY Times column, I've grown somewhat enamored with the Nobel laureate. So much so that I've developed a bit of a heterosexual man-crush. But my being smitten is not what's important right now. Moving along...

Krugman is vastly knowledgeable about a number of issues, most of which are very close to my heart. I must admit I have very little interest in international economics, which is the Princeton economist's forte. But I do have a lot of interest in politics, particularly with respect to health care and social security, as I'm a firm believer in the importance of insuring the welfare of this fine country's populace. Poverty is, after all, a despicable thing. I also have a lot of interest in climate change, and this is a topic that Krugman addresses often and with great care. Case in point: Krugman's recent column, titled 'The Truth, Still Inconvenient.'

This is a very well written and thought out essay, but there is one point in particular that I would like to emphasize. Krugman indicates that climate change deniers are guilty of a certain degree of irresponsibility. After all, if climate change is indeed a myth, then the worst that could happen is that we uselessly spend a fraction more money than normal on trying to be more responsible citizens of our planet. On the other hand, if the multitude of research studies prove to be correct and climate change is a real and dangerous phenomenon, then the climate deniers have committed an egregious act of purposeful obfuscation that could be absolutely catastrophic. So you can kind of see how the consequences of these scenarios are not really equally balanced.

I know that I am certainly biased and may be oversimplifying the situation, but I think the overall idea here is most definitely accurate. But hey, this is something I've already discussed in a previous post. It's difficult to stress, though, how important this idea is: it's all about the consequences of one's actions, and it seems to me that staunch climate deniers have done a very poor job weighing the consequences of their actions.