update on Nikon objective immersion oils

August 30, 2018 at 8:41 am | | everyday science, hardware, review

A few years ago, I compared different immersion oils. I concluded that Nikon A was the best for routine fluorescence because: (A) it had low autofluorescence, (B) it didn’t smell, (C) it was low viscosity, and (D) the small plastic dropper bottles allowed for easy and clean application.

Unfortunately, my two favorites, Nikon A and NF, were both discontinued. The oil Nikon replaced these with is called F. But I don’t love this oil for a few reasons. First, it’s fairly stinky. Not offensive, but I still don’t want my microscopes smelling if I can help it. Second, I’ve heard complaints from others that Nikon F can have microbubbles (or maybe crystals?) in the oil, making image quality worse. Finally, dried F oil hardens over time, and can form a lacquer unless it is cleaned off surfaces very well. That said, F does have very low fluorescence, so that’s a good thing.

I explored some alternatives. Cargille LDF has the same optical properties as Nikon F (index of refraction = 1.518 and Abbe Ve = 41). But LDF smells terrible. I refuse to have my microscope room smell like that! Cargille HF doesn’t smell and has similar optical properties, but HF is autofluorescent at 488 and 405 nm excitation, so it adds significant background and isn’t usable for sensitive imaging.

At the recommendation of Kari in the UCSF microscopy core (and Caroline Mrejen at Olympus), I tried Olympus Type F, which also has an index of refraction of 1.518 and an Abbe number of 40.8, which is compatible with Nikon. The Olympus oil had very low autofluorescence, on par with Nikon A, NF, and F. (I also tested low-fluorescence oils Leica F and Zeiss 518F, but their dispersion numbers are higher (Ve = 45-46), which can cause chromatic aberration and may interfere with Perfect Focus.)

I used to love the low viscosity of Nikon A (150 cSt), because it allowed faster settling after the stage moved and was less likely to cause Perfect Focus cycling due to mechanical coupling to thin or light samples, plus it was easier to apply and clean. Nikon NF was higher viscosity (800 cSt). Olympus F is higher than Nikon A (450 cSt), but acceptable.

Finally, Olympus F comes is an easy to use applicator bottle: instead of a glass rod that can drip down the side of the vial if you’re not careful, the Olympus F is in a plastic bottle with a dropper. It’s not quite as nice as the 8 cc dropper bottles that Nikon A used to come in, and I don’t love the capping mechanism on the Olympus F, but I’ll survive.

I plan to finish up our last bottle of Nikon A, then switch over to Olympus F. We also have a couple bottles of Nikon NF remaining, which I will save for 37C work (the higher viscosity is useful at higher temperatures).


Some people claim that type A was simply renamed type N. I don’t think that’s true. First of all, I couldn’t get Perfect Focus on our Ti2 to work with Nikon type N oil. Second, the autofluorescence of Nikon type N (right) was way higher than Olympus type F (left) or the old Nikon type A, at least at 405 and 488 nm:

So I’ll stick with Olympus type F. :)


Here are some example images. These are excited with 640 (red), 561 (red), 488 (green), and 405 nm (blue) and the display ranges are the same for each sample. (The dots are single fluorophores on the glass.) You can see that Cargille HF is slightly more autofluorescent (especially at 405 nm) than either the old Nikon A or Olympus type F. This matches what Cargille states for HF: “Slightly more fluorescent than Type LDF.”


RSS feed for comments on this post. TrackBack URI

  1. Thanks for sharing your follow up oil test!
    Also to pass on the credit for the Olympus oil, Caroline Mrejen (formally of technical instruments, now with Olympus) was the one who pointed out the similarities with Nikon A to us.

    Comment by Kari — August 30, 2018 #

  2. Any thoughts on Leica or Zeiss immersion oils?

    Comment by gdm — January 24, 2019 #

  3. Nikon says type A oil is now called type N.

    Comment by Ray Truant — February 13, 2019 #

  4. Note that – even though Nikon says type N is the successor of type A – type N is not recommended for fluorescence or use of PFS. My guess is that makes type N unusable for ~ 90% of the Nikon TI and TI2 microscopes out there.

    Comment by Nico Stuurman — February 13, 2019 #

  5. Ray, interesting lead. Thanks! No one at Nikon has communicated that to me, even after several emails back and forth. But maybe they did rebrand A to N. Seems strange that they would change the name but keep the formulation identical, but it’s possible. I might test it someday to see if the autofluorescence is low and if it does end up working with Perfect Focus, as Nico mentioned.

    Comment by sam — February 14, 2019 #

  6. Hi Ray. Nope, Nikon type N isn’t the same as the old type A, and it’s not usable for sensitive fluorescence microscopy that needs Perfect Focus. Too bad.

    Comment by sam — February 15, 2019 #

  7. I’m curious about the statement
    “HF is autofluorescent at 488 and 405 nm excitation”
    I have heard this repeated other places, but we have been using HF for single GFP imaging for many years and it doesn’t seem to be an issue. Where exactly does this come from other than cargille sayin ” slight autofluorescence for this oil”. Does someone have images of type HF and say olympus type f of the same sample at 488? Perhaps we should change?

    Comment by Jeff — April 19, 2019 #

  8. Hi Jeff. I added some example images. If you’re not using 405 nm, you can probably get away with using HF. I still found noticeably higher background at 488 nm when using HF compared to the old Nikon A or Olympus type F, but it wasn’t catastrophic.

    Comment by sam — April 19, 2019 #

  9. Great Thanks! But unfortunately I can’t see the images. We have been using type HF for years with single GFP and not had any problems so I guess it’s ok

    Comment by Jeffrey SpectorJeff — April 22, 2019 #

  10. Sorry, I guess TIFFs don’t work on all browsers. Changed them to JPG. I agree that, if HF is working for you, no need to change!

    Comment by sam — April 23, 2019 #

  11. We are also running into the same problem here in our lab, we’ve just about used up our final two bottles of Type A so we’re looking into suitable replacements. I’m curious, what lens specifically are you using?

    Comment by TJ — July 25, 2019 #

  12. We use multiple lenses. For example 100x/1.49NA TIRF objective.

    Comment by sam — August 14, 2019 #

Leave a comment

thanks for the comment

Powered by WordPress, Theme Based on "Pool" by Borja Fernandez
Entries and comments feeds. Valid XHTML and CSS.