Steps Involved in the Calibration of Your Pipette Note: You should check the calibration of your pipette using two different volumes. Take distilled water in a beaker and record its temperature. Gather your pipette and the correct tips based on both the small and large volumes that the pipette can dispense. Prepare the pipette for calibration. Wipe down the pipette with ethanol to kill any contaminants before beginning and make sure nothing is clogging the tip end of the pipette. Place the appropriate tip on the end and set the volume that you want to test. For calibration, test both the smallest volume and the largest volume the pipette can dispense. Both pipette types have a piston that moves in a cylinder or capillary. In air displacement pipettes, a certain volume of air remains between the piston and the liquid. In positive displacement pipetting, the piston is in direct contact with the liquid.
Lab 2: Measurement of Volume & Mass in Biotechnology Lab The ability to accurately measure specified amounts of liquids and solids is an essential skill for a biotechnology lab worker. Today, you will become familiar with the instruments used to measure volume and mass in a biotechnology lab and learn how to measure accurately. Of the metric units, volume is perhaps the most crucial as most of biotechnology (and biology) is water (or solution) based. Solutions can be measured and transferred with a range of "volumetric glassware" including: flasks, beakers, graduated cylinders and pipets. Cell density, mass, and volume measurements. Cell density is calculated by the linear relationship between buoyant mass and fluid density (red line, equation in text). The slope of this line is determined by the cell volume (Inset A) and is measured by a commercial Coulter counter on the same sample loaded in the SMR.
Purpose: Work with DNA and enzymes frequently involves measuring very small volumes, often in the microliter range. The liter is the metric volume standard, and one microliter (μl) is one millionth of a liter. To make these precise measurements, the molecular biologist uses a micropipette. Concept: Work with DNA and enzymes frequently involve measuring very small volumes, often in the microliter range. A microliter (μl) is one millionth of a liter. Liquid measurements in the metric system are made in units based on the liter where a liter is about one quart. To make these precise measurements, molecular biologists use a precision tool known as a micropipette. This tool is as basic to their lab work as a hammer is to a carpenter. Micropipettes come in many models and sizes.
Micropipettes are the type of air displacement pipettes that are used to transfer the small quantities of solutions measured in microliters, 1000 µl (microliters) equals to 1 ml (milliliter) and is the maximum amount that is commonly dispensed with the micropipettes. Micropipettes are of two types, the Fixed micropipettes, and the Variable Micropipettes. These are micropipettes are a recent introduction to micropipette fields invented by Alar Ainla in the biophysical technology lab of the Chalmers University of Technology Sweden.
Gather the necessary materials. To check the calibration of a pipette, you will need the pipette, pipette tips, distilled water, a beaker, a thermometer, a balance, and weigh boats. The balance needs to be specific to micrograms to calibrate micropipettes with a maximum of 1 µL. Measure the temperature of the distilled water. Place the thermometer in the water and leave it for at least one minute. If the red line on the thermometer is still moving, leave it for another minute. After a minute, record the temperature in a notebook. Remove the thermometer and dry it off when you are finished. Place the weigh boat on the balance and zero it out. Ideally, you will use a balance that has doors on it and is an isolated chamber. Place the weigh boat in the chamber and close the doors. If you don’t have doors, simply place the weigh boat on the balance. Press the "Zero" or "Tare" button and wait until the balance reads zero.
If used appropriately and carefully enough, the pipette can consistently deliver volumes as small as one drop ( 1/20 of a mL). In certain tests and and reagent interactions, one reactant must be administered in small volumes so that the exact rate of change or production can be precisely measured.
On the body of the micropipette is a small vertical window with three numbers. These numbers, read from the top down, tells the user how much volume the micropipette is currently set at. To change the numbers, grasp the black dial or plunger and gently twist. The numbers will then change.
The p20 micropipette is one of the most commonly used pipettes. It is used for measuring small volumes and is often the pipette of choice for loading electrophoresis gels. p20 micropipettes are used to measure volumes between 1.0 µL and 20 µL. p200 micropipettes are used to measure volumes between 20.0 µL and 200 µL.
Volumetric pipette: While there are many measuring glasswares available such as graduated cylinders, beakers, and flasks; out of all, the volumetric pipette is considered the most accurate one for calculating volumetric analysis.
Graduated pipettes are less accurate than volumetric pipettes. Mohr graduated pipettes, which are sometimes called “drain out pipettes”, are marked with a zero at the start of their conical end, while Serological graduated pipettes, also known as “blow out pipettes”, do not display zero marks.