Laboratory Techniques: Multichannel Pipettes

Questions and Answers

What is the primary purpose of a volumetric flask?

To hold a precise volume of a solution at a specific mark. (correct)

To filter solids from liquids in a solution.

To hold large volumes of liquid during heating.

To mix solutions through vigorous shaking.

Which characteristic differentiates Class A glassware from Class B glassware?

Class B glassware is primarily used for preparing standard solutions.

Class A glassware is manufactured from borosilicate material. (correct)

Class B glassware has a higher level of accuracy.

Class A glassware is made from soda-lime glass.

For which task are Erlenmeyer flasks primarily designed?

For stirring or heating solutions. (correct)

For holding accurate measurements of solutions.

For filtering liquids from solids.

For conducting titrations with high precision.

What is a common use for beakers in the laboratory?

To catch liquids that result from titrations. Signup and view all the answers

What material is Class B glassware typically made from?

Soda-lime glass. Signup and view all the answers

What is the main advantage of using multichannel pipettes?

Ability to attach multiple pipette tips Signup and view all the answers

How are automatic pipettes categorized?

According to their mechanism and volume type Signup and view all the answers

What characteristic defines a fixed volume pipette?

It dispenses the same volume every time Signup and view all the answers

What is a unique feature of positive displacement pipettes?

The sample comes into direct contact with the piston Signup and view all the answers

What is the typical volume range found in a single pipette?

0.5 μL to 1,000 μL Signup and view all the answers

Study Notes

Pipettes Overview

Multichannel pipettes can attach multiple tips to a single handle for dispensing fixed volumes into multiple wells simultaneously.
Commonly used in clinical chemistry laboratories for their efficiency and time-saving features.
Automatic pipettes can be categorized as fixed, variable, or multichannel based on volume capabilities.

Types of Pipettes

Air-displacement Pipettes: Utilize a piston for suction to draw fluid, requiring disposable tips that need changing after each use.
Positive-displacement Pipettes: Function like syringes where liquid contacts both the tip and piston, enhancing precision and eliminating air cushions, useful for viscous liquids.

Glassware in Measurements

Volumetric and Erlenmeyer flasks are commonly used for preparing standard solutions and reagents due to their calibrated capacities.
Class A Glassware: Offers the highest accuracy, made from borosilicate glass, ideal for precise experiments.
Class B Glassware: More general-purpose, made from soda-lime glass, less precise but suitable for a wide range of materials.

Pipette Types and Usages

Transfer Pipettes: Designed to move liquid with a focus on accuracy, essential for standard solution preparations.
Micropipettes: Defined as those dispensing less than 1 mL; they can be Mohr or serological types.
Disposable Pipettes: Can have calibration marks, used primarily for transferring solutions without targeting specific volumes.

Pipette Calibration and Maintenance

Regular calibration (3-4 times a year) is critical for maintaining the accuracy of automatic pipettes and non-Class A materials.
Class A pipettes do not require recalibration by the laboratory; they are accurate to within 0.1%.
Tips for positive-displacement pipettes are reusable and must fit properly to prevent carryover between samples.

Best Practices

Record pipette calibration results for long-term monitoring and adjusting performance over time.
Multichannel pipettes improve throughput in tasks such as tissue culture and enzyme assays by filling multiple wells efficiently.

Description

This quiz explores the benefits and functionalities of multichannel pipettes in laboratory settings. Learn how these tools enhance precision, save time, and improve ease of use while reducing the need for cleaning. Test your knowledge about this vital piece of lab equipment.