All systems (OryxNano, Oryx4 and Oryx8):
Sitting drop down to 100+100 nl for screening
Up to 8+8 µl drops for crystal harvesting and soaking
Contact dispensing allows "MMS" and regular microseeding
Only 10.0 µl of protein for 96 wells (100+100 nl)
- 2D grids
- Cross-Matrix (Combinatorial) experiments
- Additive Scatter Optimization
here for videos,
and here for the advantages of the Oryx4 and
All Oryx systems use multi-bore dispensing tips (microtips), which
have several independent channels to dispense small volumes. At the end
of e.g. a 3-bore tip there are three holes. Each channel dispenses a
different solution. The solutions do not mix in the tip - they mix in
the drop after they are dispensed. This means that there is no
dead-volume. Oryx8 has two chassis and can use 3, 4 and 7-bore microtips.
The microtip is on the left-hand arm.
• The microtip always touches the plate when liquids are dispensed.
This gives very reliable dispensing, especially when suspensions of e.g.
seed crystals are used, which makes the system ideal for
• Stock solutions do not come into contact with the motorized syringes, which are filled with degassed pure water - this avoids the need for
flushing out the syringes when the stock solutions are changed.
• The manual syringes on the front panel
are used to refill the motorized syringes, to remove air bubbles, and to
load stock solutions for optimization experiments.
• Large volumes, including oil for
microbatch experiments, are dispensed by the right-hand arm using the
large (2 ml) motorized syringe. A 1 ml disposable tip is used for this.
Screening for sitting drop is carried out using plates that are
prefilled with reservoir solutions. (Reservoirs can be filled manually
with a 12-channel pipette, or large-volume dispenser such as the
Liquidator 96 by Rainin). During each dispensing cycle, the tip is
first cleaned in the reservoir by
moving it horizontally through the solution. The tip then picks up e.g.
100 nl of solution from a clean part of the reservoir and transfers it
to the drop, dispensing protein simultaneously (together with seed stock
for microseeding experiments). The level of contamination has been
tested and is very low.
A very simple user-interface is used to design experiments, as shown
below. The correct plate can be selected from a database of all
well-known crystallization plates (if your favorite isn't there, let us
know!), the volumes
of each ingredient of a drop are entered in a simple form.
Individual wells can be selected or skipped by clicking on the plate
with a mouse. (The form shown below allows seed stocks and additives
to be added to drops, as
Exactly the same mechanism is used to dispense drops up to 8+8 µl for
crystal harvesting and soaking experiments, and down to 100+100 nl for
screening experiments. Smaller drops can be used but will not give
reliable results with some proteins. Evaporation is reduced by covering
the plates with a sliding shield (see below). For soaking experiments,
microseeding is highly recommended, see below. For information about
dispensing reservoirs for optimization experiments, see below.
Sliding Evaporation Shield
Since all Oryx systems use contact dispensing (the tip always touches
the plate) they give very reliable dispensing even when suspensions of
solid particles are used. This makes them ideal for microseeding
experiments. The technique of adding crystal
seed-stock to random
screens (rMMS) is a significant breakthrough in protein crystallization
that is very effective. For example, one industrial group
method to solve 38 out of 70 structures generated in a four year period,
finding particular success with antibody complexes. rMMS not only
produces more hits, it also typically generates better-diffracting
crystals – because crystals are more likely to grow in the metastable
zone of the protein’s phase diagram (see below).
Note also that in cases where only one or a few crystals are obtained in
screening experiments, the seed stock that can be made is very valuable
– often more valuable than the protein sample. It is therefore a great
advantage to be able to use the smallest possible sample of seed stock.
Using any robot from the Oryx range, seeding can be performed in a whole
96-well plate using only 1.5 µl of seed stock. This is particularly
helpful for membrane protein crystallization projects because membrane
protein crystals are often unstable and it is helpful to make seed
stocks without diluting the original mother liquor.
Videos about rMMS : (1)
Introduction and theory. (2)
rMMS experiments with an Oryx system.
Contact dispensing has another advantage: almost no protein remains in
the tip at the end of the experiment. Moreover, since only one
(multi-channel) tip is used, all of the protein for an experiment can be
placed in a single PCR tube, which also reduces waste. When they have
enough protein, most users set up 300 + 300 nl drops. For a 96-well
plate this requires only 29.4 µl of protein, i.e. only 0.6 µl is wasted.
If your pipette is accurate, there is no need to put more than the
specified amount into the tube!
Similarly if 10 nl of seed stock is added to each drop, only about 1.5
µl of seed stock is required for a whole 96-well crystallization plate.
(It is helpful to dispense around 5 µl of screen solution on top of the
All Oryx systems can carry out simple optimization experiments using three different approaches.
The standard screening software allows users to define simple 2-d grids
for sitting drop experiments. Using three or four ingredients, the user
selects the volumes to be dispensed in two corners of a rectangular
grid. The software interpolates linearly between those conditions. (The
user interface does not show the concentrations in intermediate wells,
but the volumes dispensed to each well are shown in a log.) The script
works well with plates with small reservoir volumes (e.g. the SwissCI
3-drop) because the maximum volume of any ingredient that can be
dispensed is 1620 µl. (A more sophisticated approach to optimization
that includes 2-d Grid experiments is available with the Oryx8 – see
Click here for a video
showing how to set up 2-d grids
with an Oryx
The systems' powerful combinatorial optimization” approach allows a
different additive or seed-stock to be added to each row. Each additive
is picked up from the corresponding PCR tube on the right of the table
(A1, A2 etc. on the diagram below). By arranging e.g. precipitants in
columns (P1, P2 etc.), different combinations of precipitants and
additives can be tested very quickly. This is useful for reshuffling the
ingredients of several hits, so that ingredients that are not helpful
can be eliminated quickly, and trends can be identified. For example,
certain ingredients may encourage the formation of crystals with certain
The combinatorial approach can also be to systematically identify the appropriate “dilution of a seed stock in a single experiment. We recommend using a highly concentrated seed stock
for routine rMMS screening, however this can result in showers of small crystals. It is often possible to optimize these conditions by diluting the seed stock to get around 5
crystals per drop (experiment with thermolysin shown above). For example, different concentrations of seed stock
could be placed in the PCR loading tubes shown 1 - 1E-6 dilution above. Four different conditions
could be placed into the four columns labeled P1 to P4 above.
This is a very effective way to get a really reliable supply of crystals
for data collection and soaking experiments.
Click here for a video showing
Scatter up to 5 additives (e.g. seed stocks) evenly distributed across a vapor diffusion plate. The vapor diffusion plate would typically be pre-prepared
with a 2D gradient of precipitant against salt or precipitant against pH. The robot will then distribute up to 5 additives in a
pattern across the 2D gradient. This tests the additives across a range of concentrations.
This experiment would normally be used for testing up to 5 dilutions of seed stock. It could also be used to test other additives or protein concentrations.
Click below for:
OryxNano bench space
(Visio file (part of Microsoft Office)) - Follow this link to see how much space
is required on your lab bench using the on-screen ruler. Click on the tabs at
the bottom of the screen for possible configurations. If no ruler is visible,
click on ORYXNano Specification
between Oryx8, Oryx4 and OryxNano
Specification of OryxNano
Specification of MCC control unit
Getting started with OryxNano
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