Friday, November 15, 2013

Friday Fun: Corporate Indicator? Refrigerator.

Here's a picture of our work fridge:

No, we didn't just clean it out; this is how it's looked all week. Amazing how little it's used when the company only employs a handful of people.

Gone are the niceties of early start-up life, the beer, the free soda, the fresh fruit and snacks. We don't even stock milk for coffee anymore. Note what's also missing: Forgotten lunches. Tupperware. Old birthday cake. Fast food leftovers.

That seltzer on the right? The boss's. Ditto the hard lemonade in the drawer. The Coke? The part-time facilities guy. I don't even know who owns the bruised fruit.

The champagne, however? That's mine. Relic of a more optimistic era - I was going to crack that when we won our first big contract.

Been sitting there for over a year.

Happy (?) Friday,
See Arr Oh

Wednesday, November 13, 2013

Highly Active, Barely Seen

Bench chemists know it's tough enough to control the multiple variables that go into any one reaction. But what about the ones you never saw coming?

The literature abounds with cautionary tales: Trace nickel (II) in the NHK reaction. Trace phosphate in the GFAJ "arsenic life" saga. "Metal-free" couplings found to rely upon parts-per-billion levels of Pd or Fe contaminants in "pure" sodium carbonate.

In yesterday's post, a volcanic mudpot-dwelling bacterium flourished in lab culture, but only when its growth media was doped with a rare earth element (REE). The authors had quite a bit of trouble eliminating residual metals from the growth media:
"When testing REE dependency (salts > 99% pure), it was observed that standard serum bottles resulted in a highly variable growth. . . Sand is one of the major raw materials of glass and may contain considerable amounts of REE, and Ce may be used as an additive during glass manufacturing. It was concluded that REEs in glass are extractable, at least partly, by the acidic media used."
Whoa! I confess, I've stirred hundreds of acidic solutions in glassware of all shapes and sizes, and never once have I assayed the rare earth content! And the glass wasn't the only cause for concern:
"Contact of the acidic medium with needles used for sampling was minimized as the metal seems to release REE as well. For these experiments, concentrations of trace elements were (in μM): NiCl2, 1; CoCl2, 1; Na2MoO4, 1; ZnSO4, 1; FeSO4, 5; and CuSO4, 10."
For those playing at home, some of these trace metals guest star at the ppm level in this media. Due to the materials used in glass and disposable needle manufacture, I guess there will always be a baseline of (potentially active) metal contaminants in acidic solution.

Want to take bets that one or more play roles in our favorite cross-coupling reactions?

Tuesday, November 12, 2013

Counterion Conundrum

(For Popkin's great Science News writeup, click here)
(Update - Also, Chemistry World!)

Update (11/13/13) - Blog buddy Lila Guterman of Science News has the inside scoop:
"An answer! Authors via : cerium(III)chloride heptahydrate (99.9% pure) from Sigma (cat. nr. 228931-25G)"


Fascinating news for the inorganic biochemistry fans out there: Scientists have ID'd a bacterium (Methylacidiphilum fumariolicum) living in highly acidic volcanic pools that seems to use rare earth metals in one of its enzymes. A multinational team modeled the enzyme with a variety of rare earth cores, and the bacterium appeared to selectively take them up in cell culture. Cool!

Just one small problem: What's the counterion?!?

My crack online reporting team has scoured the manuscript, finding only mentions of a mysterious Ce(III), along with triply-oxidized La* and Pr. Nowhere in the Supporting Information do they mention reagents used, and the reporter has confirmed that this subject wasn't broached.

Given the other salts the researchers added to the media, it's likely that they used either cerium (III) sulfate or cerium (III) chloride. However, Sigma-Aldrich sells no less than 10 different cerium (III) salts (Strem has over 20!), and I'm willing to bet they have markedly different bioavailability, oxidation potential, aqueous solubility...the works.

Readers, does anyone know what the cerium source is in this paper?** I certainly don't wish to draw unwarranted conclusions, but we're all still touchy over another recent dust-up having to do with a miraculous trace element.

Please let me know in the comments.

*IUPAC police: Throughout the paper, the authors refer to "Ln ions." Do you suppose they mean La (lanthanum)? Are elements abbreviated differently in other places?

**Interestingly, the authors note that their acidic growth media leached trace rare earths out of the glassware. I've never looked at that as a reaction contaminant, but I guess I'll have to start!

Thursday, November 7, 2013

Start-up, Year Two

As my tiny company hovers on the brink of non-existence, I recently passed my second-year employment anniversary. Here's how the numbers shake out for 2013:

(Year One Stats)

"Standard" 40-hour work weeks: 2
45-60 hour weeks: 46
60+ hour weeks: 4
Total hours where I've been the only employee in the facility: >300
Weekends worked: 4
Holiday + vacation + sick days used: 29
Paycheck snafus: 3

Total Reactions Run (2011-2013): >850
Synthesized compounds evaluated in disease models: 10
Total NMR Experiments (2011-2013): >1,150
Total Papers Downloaded (2011-2013): >2,200
Total Inventory Chemicals: 380
Fume Hood Failures: 3
Total boxes of gloves used (2011-2013): 23

Turnover (2011-2013): 70%
Company Interviewees: 7
Happy Hours: 1

Biz Dev
Grants Submitted: 12
Teleconferences: 63
Conferences / Events: 14
Slide Decks constructed: 36
Presentations: 5
Total Business Cards Distributed (2011-2013): 400+ 
Total Reimbursed Mileage (2011-2013): 3,100+

Total Purchase Orders (2011-2013): 317
Continuing Ed / Training Classes: 20 hours
Holiday Parties: 0

Tuesday, November 5, 2013

What's that 'Bright Orange' Chemical?

As reported by NPR this morning, the U.S. Supreme court hears the case of Carol Anne Bond, convicted of violating the Chemical Weapons Convention through her repeated attempts to poison her husband's mistress with two industrial chemicals. From NPR:
"Bond stole toxic chemicals from the chemical manufacturing company where she worked and ordered other chemicals over the Internet. She combined the chemicals into a compound that is potentially lethal in small amounts — and is also bright orange. Bond spread the toxic material on her rival's mail, mailbox, front doorknob, car door and other surfaces.
But because of the orange color, the mistress, Myrlinda Haynes, easily spotted the chemicals and avoided any injury except a thumb burn."
 I tried to look for information on the identity of this "bright orange" substance. Digging into the SCOTUS brief, it seems Ms. Bond purchased two chemicals:
". . .petitioner [Bond] decided to punish Haynes. She purchased some potassium
dichromate (a chemical commonly used in printing photographs) from, and stole a bottle of 10, 10-chloro-10-H-phenoxarsine (an arsenic-based chemical) from her employer. Petitioner knew the chemicals were irritants and believed that, if Haynes touched them, she would develop an uncomfortable rash."
According to this oral argument from 2011, Ms. Bond had been a microbiology technician with Rohm & Haas, from whom she nabbed the arsine compound. What I haven't been able to figure out from the stories or briefings is whether she intended the combination of two potentially poisonous, irritant substances to function apart, or to perform some sort of solid-phase oxidation to, for example, phenoxarsine oxide (a known antimicrobial compound).

This case needs more chemical context...paging Deborah Blum!