Diamond nights

Yesterday morning I awoke in crumpled clothes on a strange sofa, my mouth feeling furry and unwashed. I’d crashed there at about 5.30 am and only snatched a couple of hours of fitful sleep. As I gazed blearily at unfamiliar surroundings, a woman I barely recognised appeared and asked if I’d like a cup of tea. I nodded and mumbled thanks.

Partying hard in the run-up to Christmas? No, it was the aftermath of another synchrotron trip, this time to the Diamond Light Source just outside Didcot.

The symptoms will be familiar to most protein crystallographers: puffy eyes, grey complexion, mental derailment, churned up guts that are no longer in sync with mealtimes. Jet-lag without ever having left the ground.

Three of us had arrived bright-eyed on Wednesday morning for our first data collection trip on the micro-focus beam-line (I24) at Diamond. The beam-line is a work in progress since the experimental station isn’t quite fully operational. But it works well enough to be useable and in a mutual back-scratching agreement with Gwyndaf, the beam-line scientist, we’d managed to snag some time for our project. I24 focuses the intense X-rays generated by the accelerator ring into a beam that is only about a tenth of the thickness of a human hair—around 10 µm—just what we needed since our crystals were tiny needles of about the same size.

 

Crystal mounted on I24 at DLS
The crystal (invisible!) is on the end of the horizontal pin in the centre of the photo

 

It’s amazing that such miniscule crystals can be used to scatter X-rays into the diffraction patterns needed to figure out the structure of the molecules within. But tiny crystals make for tricky experiments. So we fiddled for hours, scooping up each one and freezing it in a stream of nitrogen cooled to 100K. The frozen crystal—trapped in a gobbet of cryo-solvent—is imaged by a microscope so that we can manoeuvre it precisely into the path of the beam. But seeing a tiny crystalline shard embedded in a glistening bead that bends and reflects the light is no easy feat.

Even then the X-rays are so intense and the crystals so small that ten short exposures were enough to frazzle the protein. So you stop and shift the crystal needle along to blast a new section for another 10 exposures.

And so the night passed, myself, Olga and Jingjie locked in intense rounds of sample preparation and analysis, of activity and concentration. We were cheered when rows of dark spots appeared on the detector, dismayed when there were none. Midnight came and went and the wee small hours were upon us. It’s strange, but you can keep going as long as you’re active, as long has you have a purpose.

But we finished around 5 am, tidied up and crashed. And when you do stop your body finally catches on to the punishment you’ve been giving it and strikes back with a vengeance. We slunk back dead-beat from Diamond.

The name was well chosen: diamonds are bright but they’re also hard. Well hard.

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18 Responses to Diamond nights

  1. Brian Derby says:

    Steve – dfoes this mean you are a Diamond Geezer?

  2. Stephen Curry says:

    Definitely! Though that was true even before I went to the new synchrotron!

  3. Katherine Haxton says:

    I’ve never had the pleasure of Diamond or Daresbury, but I’ve been a beam line widow many weekends when my partner is there. Too many hours staring at the beam status, hoping that it doesn’t go down, and hoping for no dispondent ‘nothing is working’ phone calls!
    I hope the results are worth their weight in microcrystalline diamonds!

  4. Stephen Curry says:

    Cheers Katherine. My wife has suffered much the same. In fact she refers to the machine as the stinkrotron. It is usually fairly tough going on each trip but I do rather like the total immersion in the science that it offers – for me a pleasant change from the constant interruptions of office life!

  5. Sara Fletcher says:

    I did feel bad running off at 6pm and leaving you to the mercy of the beamline! I hope you got some useful data in the end. I reallt feel for our scientists who, especially when the beamline is new, spend many nights and weekends helping out the users. Whenever I start getting misty-eyed about how I loved being an active research scientist I remind myself of those long, often thankless hours!

  6. Stephen Curry says:

    You have no need to feel bad Sara – we knew what was ahead of us. And yes, I think we got something useful in the early hours of Thursday morning, though only after we’d woken up Danny to sort out a goniometer crash (don’t ask), which he did very willingly. The hours are long but not entirely thankless!

  7. Sara Fletcher says:

    Glad to hear that anyway! Are the sofas at Diamond comfy?!

  8. Stephen Curry says:

    Rather firm actually and curved, but not bad a all. You can try them out yourself – they’re the ones in the entrance atrium. Not a very private space for sleeping!

  9. Sara Fletcher says:

    That is a bit rubbish, I’m surprised you didn’t get woken up by the cleaners! We really should look into something better for late night visitors if Ridgeway House is full. Or get the Oxford tube to stop outside Diamond House!

  10. Brian Derby says:

    Luxury – Isis doesn’t even have sofas.

  11. Stephen Curry says:

    @Sara – I’m not complaining since we hadn’t pre-booked anything and we actually able to get a room for one of us. The User Office offered to book a B&B but we declined.
    @Brian – you should complain!

  12. Brian Derby says:

    I have not used neutrons for a few years now but I always preferred the ILL to ISIS because the food was better. Neutron experiments are much slower than X-rays so you get a better chance of some sleep. However, I may be using the tomography line at Diamond in the future so sleepless nights beckon.

  13. Stephen Curry says:

    Well good luck with the tomography. I think you’ll be pleasantly surprised by the working environment at Diamond. I can’t speak for the food since I only managed to grab sandwiches from a vending machine. For lunch and dinner!

  14. Andreas Forster says:

    I don’t want to split hairs, Stephen, but you don’t get too far with a beam focused to the width of a hair. Mine, at 60 um, is very fine. 100um is more typical. (Amazing things you remember from your physical lab course.)
    Thanks for your blog.

  15. Stephen Curry says:

    Thanks for the correction Andreas. Bloody useless internet information! Mind you, I should have realized my error since we use cat whiskers (naturally moulted, not plucked!) to manipulate our crystals – since these are even finer than human hairs – but even those would have been too cumbersome for the crystals we were shooting on this trip.

  16. steffi suhr says:

    we use cat whiskers (naturally moulted, not plucked!) to manipulate our crystals
    That is one of the most intriguing bits of information yet. Whoever thought of that first?

  17. Bob O'Hara says:

    And who follows their cat around waiting for it to drop whiskers?
    If you want can hair, naturally moulted, I can collect plenty for you. I have a factory curled up in the chair next to me as I write.

  18. Stephen Curry says:

    @Steffi – I’m not entirely sure who was first to use cat whiskers but I first came across the technique in a paper by Enrico Stura in Ian Wilson’s lab:

    Stura, E.A., and Wilson, I.A. (1990). Analytical and production seeding techniques. Methods 1, 38-49.

    Whiskers are much finer than human hair but retain enough stiffness to be useful for pushing crystals around or scratching off small fragments to use for seeding—crystallisation is a lot like gardening… The whisker is attached to the thin end of a pasteur pipette with a bob of wax to create the tool that we use. Stura actually recommends chinchilla whiskers as superior to those from the cat but I don’t have access to one of those!
    @Bob – no need to worry about the cats. I get whiskers from my sister-in-law who finds them lying around the house and they last a very long time. We now have a cat ourselves but I have yet to find a single whisker. Maybe they only start dropping off when the cats reach a certain age (ours is quite young)?

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