VistaLab MLA Series User manual

Operator’s Manual
MLA Digital Pipettes
Introduction
MLA Digital Pipettes are “to deliver”air displacement adjustable volume instruments. Three
models are available covering a volume range of 10 to 1000µL. Volume is adjusted by rotating
the plunger. The plunger clicks in place for any desired setting. The volume display is located
in the body of the pipette.
Pipette Tips
It is recommended that MLA Pipettes be used with MLA Pipette Tips. The use of tips from
other sources may degrade the pipette performance. For information on MLA Pipette Tips
refer to the Pipette Information Table.
Pipetting Procedure
a. Rotate the plunger to display the desired volume (clockwise to decrease and
counterclockwise to increase).
b. Using MLA Pipette Tips, press the pipette nozzle firmly into a fresh tip.
c. Fully depress the pipette plunger and then immerse the tip into the solution (approximately
1/8 inch-3mm deep).
d. Smoothly release the plunger and allow the solution to enter the pipette tip.
e. Remove the tip from the solution and touch the tip against the side of the vessel to remove
any solution that may have adhered to the outside of the tip.
f. Place the tip against the side of the receiving vessel as close to the bottom as possible or,
if the vessel contains liquid, as close to the liquid as possible. Smoothly depress the plunger.
g. While holding the plunger depressed, slowly withdraw the tip keeping it against the wall of
the container.
h. Release the plunger and remove the tip by applying a slight upward pressure to the bonnet.
(See Figure 1)
VistaLab Technologies, Inc.
27 Radio Circle Drive
Mt. Kisco, NY 10549 USA
[phone]
www.vistalab.com
326720 Rev. C
Volume Range Catalog No. Color Increment
10 to 50µL 1136 Green 0.1µL
50 to 200µL 1137 Red 0.2µL
200 to 1000µL 1138 Gray 1.0µL
Specifications Table
Volume Volume Change Volume Acceptable Accuracy
per 1/2 revolution Setting Range (µL)
10 to 50µL 2.5µL Low 10µL 9.5 - 10.5 ±5%
Mid 30µL 29.1 - 30.9 ±3%
High 50µL 49.0 - 51.0 ±2%
50 to 200µL 5.0µL Low 50µL 49.0 - 51.0 ±2%
Mid 125µL 123.75 - 126.25 ±1%
High 200µL 198.0 - 202.0 ±1%
200 to 1000µL 25µL Low 200µL 198.0 - 202.0 ±1%
Mid 600µL 594.0 - 606.0 ±1%
High 1000µL 990.0 - 1010.0 ±1%
Pipette Information Table
MLA Pipette Tips
Volume Color Seal Kit Stacked Bulk Sterile
Rack
10 to 50µL Green 9091 9025 4025 2025
50 to 200µL Red 9092 4225 2027
200 to 1000µL Gray 9094 9026 4026 2026
4226 2028
Accessories
Nozzle Inserts 8066
Pipette Stand 1700
pipette

Hints
a. When pipetting serum or other biological fluids, a liquid film may be retained in the tip that
may change the pipetted volume. Pre-wetting the tip with the liquid to be pipetted can
reduce this effect.
b. Smoothly depress and release the plunger and maintain the same speed of action for all
samples. Do not let the plunger snap back.
c. Fully depress the plunger before inserting the pipette tip into a solution. This will prevent
an air bubble from forming in the solution.
d. Hold the pipette as vertically as possible at all times. Insert the tip to the same depth
each time.
e. If an air bubble forms in the tip during intake, return the sample, discard the tip and apply
a fresh tip.
f. Remove and clean the nozzle insert daily. Replace the nozzle insert if necessary.
g. Check that the nozzle assembly is screwed firmly into the pipette body.
Calibration
Calibration is accomplished by adjusting the plunger shaft. Digital Pipettes are factory calibrat-
ed at three settings across the pipetting range. Factory tests and calibration are performed
at 21.5 ± 2oC using distilled water. To change calibration proceed as follows:
a. Determine the pipette delivered volume by testing the pipette at the lowest volume setting.
NOTE: Gravimetric or colorimetric techniques may be used to determine the pipette
delivered volume. A procedure for the gravimetric method, or information about a
MLA Pipette Calibration Kit using a color dilution principle, can be obtained from the
Technical Service Department.
b. While holding the plunger between the thumb and forefinger, unscrew and remove the
plunger cap by rotating it in a counterclockwise direction. The plunger can be extended
for easier holding by increasing the digital display to a higher volume.
c. Allow plunger cover to drop down to release the plunger gear shaft.
d. With a small bladed straight slot screwdriver or fingers, rotate the plunger shaft clockwise
to decrease the volume and counterwise to increase the volume.
e. The approximate change in volume for a 1/2 turn is 2.5µL for the 10-50µL, 5µL for the
50-200µL and 25µL for the 200-1000µL Digital Pipette.
f. Pull the plunger cover up and re-engage plunger gear shaft. Hold the plunger cover up
and replace the plunger cap.
g. Retest the pipette volume delivery at the low setting.
h. Test the pipette at mid and high settings.
If further adjustments are required, return the pipette to the low volume setting and adjust
plunger shaft as needed. Retest the pipette volume delivery at the low setting before continu-
ing to the mid and high settings. Ensure that each setting is within the acceptable volume
range. For specifications, see Specifications Table.
Maintenance
During factory assembly, the internal parts of the pipette (plunger, seals, etc.) are lubricated
with grease. Unless the pipette is used with corrosive chemicals or solvents, routine cleaning
and lubrication should only be necessary at 6 month intervals. Lubrication is necessary if the
plunger movement is rough or does not return to the “up”position.
The nozzle and the nozzle insert in particular should be cleaned regularly. In case of acci-
dental sample aspiration the nozzle assembly and insert should be cleaned immediately.
Cleaning should be done with a lint-free cloth dampened with alcohol. Refer to Figure 2 for
nozzle insert removal.
Should the pipette fail to operate or if the delivered volume is low, the seals should be
checked for wear and replaced if necessary. Instructions for pipette disassembly and seal
replacement can be found in the appropriate seal kit. When reassembling the pipette, align
the display cutout on the pipette sleeve with the digital display. Twisting the sleeve once
placed onto the pipette body can cause the alignment pins to break.
MLA Digital Pipette Assembly
10 to 50µL and 50 to 200µL
200 to 1000µL
Sleeve
Alignment Pin
Plunger
Plunger
Plunger
Cap
Body
Bonnet
Seals
Nozzle Cover
Nozzle Assembly
Spring Cap
Assembly
Display Cutout
Plunger
Cap
Body
Seal
Digital
Display
Bonnet
Sleeve
Nozzle Cover
Display Cutout
Nozzle Assembly
Alignment Pin
Digital
Display
Figure 2:
Nozzle
Insert
Removal
Figure 1:
D-Tipping