Eppendorf Combitips advanced User Manual
Page 5

Operating instructions
Combitips advanced
®
English (EN)
5
E
Eppendorf Quality
Eppendorf Quality is an Eppendorf
AG purity grade for consumables. Eppendorf Quality meets the
requirements for standard products, e.g., precision, accuracy, wetting behavior and tightness.
G
Graduation
Incremental graduation of a range, a surface or a volume.
M
Maximum volume
The maximum volume that can be used for dispensing.
N
Nominal volume
The maximum dispensing volume of a Combitip in conjunction with the selected dispensing device. The
term "nominal volume" comes from the ISO
8655
standard.
P
PCR clean
PCR clean is an Eppendorf
AG purity grade for consumables. PCR clean meets the requirements for
standard products, e.g., precision, accuracy, wetting behavior, tightness. PCR clean also meets the
requirements with regard to absence of human DNA, DNase, RNase and PCR inhibitors.
Consumables with the PCR clean purity grade are controlled and certified by an external laboratory.
Certificates are available for downloading from our webpage www.eppendorf.com.
Positive displacement principle
The liquid comes into direct contact with the Combitip piston during aspiration and dispensing. Unlike with
a pipette, the liquid and piston are not separated by an air cushion. A small air bubble is visible at the piston
during dispensing.
R
Random error
Precision. Describes how large the deviations of several measurements are from each other, if the same
volume is measured several times.
Remaining stroke
Liquid reserve. The liquid which remains after all dispensing steps have been completed. You can discard
the liquid of the remaining stroke or reuse it.
Reverse stroke
After aspiration, the piston is moved into a defined position. Liquid is dispensed during this piston
movement. The reverse stroke is not a dispensing step.