Pipettes are typical laboratory tools that are utilised in the fields of chemistry, biology, and medicine. They are used to convey a predetermined volume of liquid and are frequently employed as media dispensers. In this article, we will tell you all about the graduated pipette.
What is a Graduated Pipette?
It is a tube made of glass or plastic that is straight, and at one end it has a narrowing that is termed a conical tip. The other end of the tube has a nozzle. They are calibrated in very small steps, so different amounts of liquid can be measured in amounts from 0.1 to 25 millilitres (ml).
Because of its broad neck, the precision with which it can measure liquids is inferior to that of the volumetric pipette. They are used in situations where a large number of solutions must be taken but the level of accuracy required is low. They can be used to measure volume and move liquid samples from one container to another.
The graduated glass pipettes can be categorised as either Mohr pipettes, also known as subterminal pipettes, or serological pipettes, also known as terminal pipettes. The Mohr pipette’s graduation stops before the tip of the tube, whereas the serological pipette’s graduation extends all the way to the end of the tube. This is the primary distinction between the two.
Characteristics of the Graduated Pipette
The following are some of the most important characteristics of graduated pipettes.
- Plastic or borosilicate glass is used in their construction.
- There are lines running down the body of the tube that provide an indication of the overall capacity. These have numbers on them that represent the amount of liquid that is currently in the line.
- Even though the graduated pipette can measure quantities from 0.1 to 25 ml, the most common amounts used in labs are 1 ml, 5 ml, 10 ml, and 25 ml.
- The specifications that indicate: its maximum volume is printed on the neck of the pipette; the size of their divisions, represented as 1/10, 1/100; the calibration temperature; and a legend identified as TD or TC, by the acronym in English of To Delivery (ex) or To Contain (in), which means to pour or empty, respectively. Additionally, the specifications indicate the temperature at which the pipette was calibrated.
- Pipettes that measure very small amounts of fluid can give a fairly accurate measurement, while pipettes that measure larger amounts of fluid can give a less accurate measurement.
What is the Graduated Pipette used for?
In most laboratories, particularly those dealing with chemistry, biology, or medicine, the use of graded pipettes is required. On one side of this pipette is a graduated scale that can be used to measure accurately the amount of different liquids.
Understanding of the instrument and consistent practice are required in order to utilise these in the correct manner. There are a few things of a more general kind that need to be taken into account:
It is necessary to be familiar with the right way to hold the pipette. The most effective way to grasp it is in the upper third, in the space between the thumb and the middle finger.
They have a graduation that can be used to determine the volume, but it is important to keep in mind that for an accurate measurement function, the final measurement (or the total capacity of the graduated pipette) is more accurate than the intermediate measures. This is because the volume is measured at the end of the pipette. Because of this, it is suggested that the pipette be chosen based on the exact volume that needs to be measured.
In order to collect the liquid that is going to be measured, the pipette has to be positioned approximately 6 millimetres above the base of the container.
Avoiding potential dangers by drinking the liquid through your mouth is not a good idea. For this reason, either a rubber pipette bulb or pipette pump is used, and once the desired amount has been dispensed, the nozzle is plugged with the pointer finger of the index hand.
Filling can also be accomplished by the use of other methods, such as injection or ascent.
After the liquid has been transferred into the pipette, the pipette should be positioned at an angle of between 10 and 20 degrees.
You can let go of the bottle’s contents by just lifting your index finger.
Because the parameters of the pipette indicate the calibration, it is quite important to have a solid understanding of those specs. For example, “1ml in 1/100 TD 20°C” indicates that the pipette is calibrated in divisions of 1/100 and can dispense up to 1 ml of liquid at temperatures no higher than 20°C.
In addition, it is not uncommon for graduated pipettes to additionally have the abbreviation “AS” engraved on the tube, beside the parameters. This is done for quality control purposes. This abbreviation, which is often located below the volume of the pipette, denotes the precision of the categorization. “A” stands for the maximum level of precision, while “S” stands for quick delivery.
MEDILAB’s Graduated Pipettes:
MEDILAB is a leading manufacturer of laboratory glassware including Calibrated Volumetric Glassware. High-quality borosilicate glass is used in all of MEDILAB’s laboratory glassware to make our products comply with the set international standards.
Graduated Pipette by MEDILAB is made and calibrated with accuracy at our in-house calibration lab in accordance with ISO/DIN Standards, ascertaining exact Class A accuracy so that it matches the high standards our customers have gotten used to.
Contact Us
Therefore, if you want some quality graduated pipette, you can write to us at [email protected] or you can call us at +91-9896330136 or +91-8607777500 and we will be happy to assist and guide you.
