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Monthly Maintenance
Clean the Bottles and Tubes
• Clean the dispense and rinse bottles and supply tubes with deionized water before the first use, before each refill, and if they have been idle for any length of time.
• Accumulated algae, fungi, or mold may require decontamination; see page 58.
Clean the Manifold
Regular rinsing helps to keep the manifold clean and the dispense tubing clear, and will increase the life of the tubing. Follow the Decontamination procedure starting on page 58 to disinfect the manifold and tubing.
If you suspect a particular problem is related to the manifold (for example, clogged tubes can result in uneven dispensing), you should perform a thorough cleaning of the manifold. To clean the manifold:
1. Turn off and unplug the instrument.
2.
3.
4.
5.
Remove the mist shield. See
Figure 7
in Chapter 2.
Disconnect the tubing from the back of the manifold. See
Figure 5
in
Chapter 2.
Remove the thumbscrews and the manifold. Using a lint-free disposable towel, thoroughly clean the outside of the dispense tubes.
Run hot water through the inlet fitting. Check to see if water comes out of all of the dispense tubes. If not, soak the manifold in hot soapy water and repeat. Clean the tubes with the stylus if necessary (see below).
Clean (“Stylize”) the Dispense Tubes
Note: The autoclavable manifold has removable dispense tubes. We do not recommend routinely removing these tubes. In the case of a particularly difficult problem with any one channel, however, a tube may be removed and cleaned individually, or replaced.
The manifold dispense tubes do not need to be “stylized” unless there is a problem.
Periodic rinsing helps prevent the need for stylizing. If the previous steps are not completely successful, try the following:
1.
2.
Remove the two gray plugs from the ends of the manifold.
Tip the manifold on end and flush hot water through this open channel.
3. Using the supplied stylus (PN 2872304), clean the insides of all of the dispense tubes.
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7.
8.
9.
4.
5.
6.
Tip the manifold on end and flush hot water through the open channel.
Rinse the manifold with deionized or distilled water. Reinsert the gray plugs into the ends of the manifold. Check to see if water comes out of all of the dispense tubes.
Remount the manifold and replace the tubing. See
Figures 1 and 5
in
Chapter 2.
Replace the mist shield.
Run a Prime program using 40 ml of deionized water.
Verify dispense performance visually, or by performing the appropriate
Dispense Precision and Accuracy Tests in Chapter 5.
Clean the Plate Carrier
Note: Each plate carrier is specifically aligned to each MicroFill™. Do
not adjust the carrier’s nylon screws or interchange the carrier with another.
If liquid has overflowed onto the plate carrier, some crystal buildup may occur and prevent the plate adaptor from seating correctly onto the carrier.
1. Remove the carrier:
• Move it to its full “out” position (turn the dispenser on, wait for the system test to complete, and then turn the dispenser off). Make sure the manifold and tubes are over the priming trough (“home” position).
• Carefully lift the carrier
front
off the rail, avoiding contact with the manifold tubes.
• Carefully lift the carrier
rear
off the rail, avoiding contact with the manifold tubes.
2.
3.
Clean the carrier using soap and water or 70% isopropyl alcohol.
Replace the carrier:
• Hold the microplate carrier over the rail so that the trough is to the rear of the dispenser.
• Line up the pin on the underside of the carrier with the slot on the carrier transport.
• Snap the two carrier clips onto the rail. The pin must sit in the slot.
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Clean the Plate Carrier Transport Rail
Important!
Do not allow the alcohol or water to seep in between the rail and the plate carrier transport mechanism that rides on the rail. Follow the instructions carefully to prevent this.
If liquid has overflowed onto the stainless steel plate carrier transport rail, some crystal buildup may occur, preventing the carrier from moving properly.
To clean the plate carrier transport rail:
1. Turn off the instrument.
2.
3.
4.
5.
6.
Carefully lift the microplate carrier off of its transport mechanism.
Moisten (do not soak) a cloth with alcohol and wipe the back half of the rail.
After several minutes, wipe the rail with a cloth moistened (not soaked) with deionized water. Wipe with a dry cloth.
When the back half of the rail is completely dry, slide the plate carrier transport mechanism to the back of the rail.
Repeat step 3 for the front half of the rail.
When the front half of the rail is completely dry, replace the microplate carrier and turn on the instrument.
Clean/Replace the Check Valves
Note: The check valves for autoclavable dispensers do not twist open.
If the check valves leak or become stuck, you can either clean or replace them.
To order replacment check valves, contact BioTek Customer Service.
To clean a check valve:
1.
Pull the tubing off the check valve and pull the valve off the syringe pump port. See
Figure 3
in Chapter 2.
2.
3.
Insert the stylus into the feed end of the valve to hold it open (observe arrow on valve indicating flow direction).
Flush with hot water. If necessary, for the
non-autoclavable
model, the check valve body twists open to allow disassembly and cleaning of internal components. Note proper orientation for reassembly.
4. Replace the valve and the tubing.
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After replacing a check valve, we recommend that you
recalibrate the backlash
(see below) to ensure optimum accuracy performance.
Calibrating the Backlash
Equipment Required
• A minimum 3-place precision balance (all data from 0 to 99 grams)
• Supply bottle
• Priming plate
• Supply Tubing Sets:
For AF1000 Dispensers (PN 7140505)
For AF1000A Autoclavable Dispensers, use PN 7140510, or use the Organic
Solvent Tubing Set, PN 7140514 .
Setup
1.
2.
Connect the dispenser to a supply bottle that is half-filled with deionized water.
The deionized water container must be at the same level as the dispenser.
The liquid level should be 3” (102 mm) from the bench top.
While calibrating and testing, maintain the liquid level in the supply bottle at half the 3-inch column height, but start with more fluid to allow for priming.
Attach the fitting of the long tube to the supply bottle. Push the opposite end of this tubing onto the bottom port of the syringe pump (see
Figure 3
in Chapter 2).
The arrow of the check valve must point toward the syringe pump.
Note: For AF1000 dispensers, the check valve will be closer to the syringe pump than to the manifold. For AF1000A dispensers, the check valve will be closer to the manifold.
3. Push one end of the short supply tube onto the top port of the syringe pump. Push the other end over the barbed fitting on the manifold.
Select the Manifold (AF1000A Dispensers Only)
Before setting the backlash, it is necessary to select the manifold being tested.
Follow the menu path shown below:
UTIL > SETUP > MAN > 16ch or 8ch-96 or 8ch-24 >
MAIN MENU KEY
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Create a Dispense Program
The backlash is adjusted for a 20 μl dispense volume. Create a program that dispenses 20 μl per well at dispense rate 2. Follow the menu path shown below:
DEFINE > CREATE > DISP > key in a program name > set the
DISPENSE VOLUME to 0020 and the FLOW RATE to 2 > MAIN MENU
KEY > YES
Prime the Plate
1.
2.
Place the microplate adaptor into the carrier, and place the priming plate into the adaptor.
Follow the two menu paths shown below:
RUN > PRIME > OPTIONS key until New_Buffer_Prime is displayed > ENTER KEY to select the program > ENTER KEY to start the program > When the prime is complete, press the REPEAT soft key and prime again > MAIN MENU KEY
3.
RUN > DISP > OPTIONS key until the newly created
Dispense program is displayed > ENTER KEY to start this program > ENTER KEY to select the defaults for the first strip to dispense and the last strip to dispense > ENTER
KEY again to start the program
The MicroFill™ will dispense 20 μl per tube into the priming trough.
Empty the Priming Plate as needed.
Calibrate the Backlash
1.
Empty/dry the priming plate, place it on a three-place balance, and then tare the balance.
2.
3.
Place the priming plate onto the adaptor and run the 20 μl Dispense program created above.
When the program is complete, carefully remove and reweigh the plate, to determine the
Actual Weight
.
The
Expected Weight
is:
• 7.680 g for 16-channel manifolds
• 1.920 g for 8-channel manifolds (AF1000A versions only)
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4.
5.
6.
Calculate the volume (weight) error and the backlash adjustment that needs to be made.
• Subtract the Actual Weight from the Expected Weight and divide by the number of columns dispensed.
• Divide the result by 0.0033 for AF1000A instruments, or 0.0031 for AF1000 instruments, and round to the nearest whole number.
Example: 7.680 - 7.550 = 0.130, 0.130/24 = 0.00542, 0.00542/0.0033 = 1.64 rounded to 2. The backlash setting needs to be adjusted by 2.
Example: 1.920 - 2.010 = -0.09, -0.09/12 = - 0.0075, -0.0075/0.0033 = -2.27 rounded to -2. The backlash setting needs to be adjusted by -2.
Adjust the backlash as necessary:
UTIL
Î TESTS Î press the SHIFT key while simultaneously
pressing the HIDDEN KEY #2 (space between the Main Menu and Previous Screen keys)
Î SYR Î BKLSH Î enter the
new number
Î ENTER KEY Î MAIN MENU KEY
Repeat steps 1 through 5 until the volume dispensed is within one backlash unit of being exact:
• AF1000 dispenser: ± 0.112 ml
• AF1000A dispenser w/16-channel manifold: ± 0.119 ml
• AF1000A dispenser w/8-channel manifold: ± 0.059 ml
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Autoclaving the Syringe Head
This section applies to autoclavable versions of the MicroFill™ only.
Note: Refer to Figure 2 in Chapter 2 when performing steps 1-3.
1.
2.
3.
Use the supplied 3/32” (2.39 mm) hex wrench to remove the two mounting screws that hold the syringe head to the rear of the instrument.
Pull the syringe head straight back and off of the piston.
Use the hex wrench to loosen the setscrew and then remove the piston.
Important!
The piston and syringe head must be autoclaved separately from one another (see
Figure 10
below).
Ensure that the piston is removed from the syringe head before autoclaving.
If a mistake is made and the piston is set in the syringe head through the autoclave cycle, remove the piston from the syringe head and run the piston (or both piston and syringe head) through the autoclave again.
4.
5.
Autoclave at 134°C and 216 kPa for 3 minutes, or 121°C and 115 kPa for 30 minutes. The manifold, tubing, check valves, and supply bottles may also be sterilized in the autoclave.
Replace the components as described in Chapter 2.
Figure 10: Autoclave the piston (left) and syringe head (right) separately
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