If you purchased one of our portable equipment sets, you received a set of fixed-volume pipettes. These pipettes allow you to run ATP analyses in the field without worrying about damaging your expensive adjustable pipettors. They are light, portable, and easy to use, but they do require some care and the occasional maintenance check to ensure you’re getting the most accurate ATP results.
Here are a few quick tips to help ensure your pipettes are in tip-top shape:
1. Always check your fixed-volume pipettes for damage before use:
- Test the plunger to make sure it moves freely and doesn’t stick.
- Ensure the top is screwed on tightly.
- Ensure no sample has built-up around the tip or inside the pipette.
2. On a regular basis, or if in doubt, check the volume dispensed by each fixed-volume pipette.
This can be done by either:
- Pipetting into a graduated cylinder and ensuring the appropriate volume is dispensed.
- Taring a small container on a balance and pipetting an aliquot of water with the pipette being tested. The water should weigh as follows:
- Blue Pipet: 100 ul = 0.10 g
- Beige Pipet: 1.0 ml = 1.0 g
- Red Pipet: 300 ul = 0.30 g
3. Hold the pipette upright when transferring fluid.
Inverting it can allow sample or reagent to contaminate the inside of the pipet tip and affect the volume of fluid transferred. It’s also important to hold the pipette as vertical as possible or at the same slight angle each time.
4. Be consistent.
Inconsistent technique can increase the variability between ATP analyses so take care to never reuse pipet tips for different solutions, and if you flush the tip with sample or reagent before transferring, be sure to do this for all samples tested.
5. Replace pipettes annually.
It’s ideal to replace pipettes used in the field annually to reduce the risk of pipet damage and contamination which can skew ATP results.
You’ll find a handy infographic here that can be used as a quick reference guide and a how-to video below that shows you what to look for.
How to check your fixed-volume pipettes and improve your pipetting technique.
All our kits and equipment are designed with portability and field-use in mind and if you have any questions about the equipment or our test methods, please contact our technical support team for more information and other tips and tricks.