Artel stresses importance of pipette calibration

The firm helps with liquid handling quality, productivity and compliance challenges in laboratories.

Bjoern Carle, product manager at Artel, said it does not necessarily depend on how much work a lab is doing but on the risk it is willing to take.

“Pipettes are used in laboratories in many different capacities, it starts with sample preparation and dilutions to the use of very accurate and precise volumes in analytical tests and analytical assays which require pipettes to work fine,” ​he told FoodQualityNews at Pittcon 2017. ​

“To ensure pipettes are working fine and delivering exactly the volume that you intend them to deliver you need to calibrate those pipettes on a regular basis, it is a quality check and ensures the researcher or the laboratory technician that the correct amounts have been delivered.​

“The pharma industry has been working with very small volumes with PCR analyses and other tests for a very long time but the food industry is catching up especially as the FSMA has been put in place. We have seen a quite a significant uptick in enquiries and we have a number of customers in the food industry who recognise the benefits of our system and are using our technology.” ​

Avoid working with defective pipette​

Carle said a pipette fails without sending an email notification.

“One of the small highly precise parts could break at any time, so if you simply assume the pipette is good for six months or one year after a calibration day you may actually work for some time with a defective pipette,” ​he said.

“Laboratories usually assess the risk for each of their tasks, assays or sample preparation steps and then have to think back on how critical it is to ensure the pipette is working well. ​

“I know of customers who calibrate or check their pipette for proper functionality every day or before every critical assay they conduct, other calibration frequencies are on a monthly basis, quarterly basis, semi-annually and also annually but I would discourage such long calibration intervals.”​

The smallest volume calibration and measurement capability (CMC) means the pipette is calibrated to the lower possible level of uncertainty, allowing for repeatability and increased confidence in results.

Calibration standards​

ISO 8655 is a calibration standard in seven parts.

“Adherence to ISO 86/55 is voluntary but it gives a calibration laboratory all the specific guidelines and instructions on how to calibrate pipettes,” ​said Carle.

“Other pipette calibration standards are ASTM E1154 or FDA GMP and GLP guidelines that have pipette guidelines without being as specific as the ISO and ASTM standards. ​

“Quite often in the food industry FDA standards are being adhered to as well as other ISO standards, ISO 17025 is a very common analytical laboratory standard and that standard accords for all laboratory equipment which includes pipettes.”   ​

Artel’s PCS system Pipette Calibration System verifies the volume dispensed from any single-channel pipette and calibrating single-channel pipettes.

It uses ratiometric photometry and standardized dye solutions to determine the dispensed volumes.

Carle said PCS software can assess the technique of operators such as laboratory technicians as the best performing instrument is only as good as the operator using it.

“So the software allows set up of training plans for each operator so he or she can be tested with exactly those pipette volumes that they are using in their day to day work and the tolerances that they need to adhere to based on their work function. ​

“So it allows the laboratory manager to fully customise each operator’s training and performance assessment just like he can fully customise the calibration requirements for each of the pipettes in the organisation.”​

Software aid​

The software can also alert the laboratory manager if anything goes wrong.

“Let’s look at the example of a pipette calibration. So for a pipette the laboratory manager would determine the calibration frequency, he will also determine at which volumes the pipette needs to be calibrated, how many replicates at each volume need to be taken and what the pass and fail tolerances are for accuracy and precision​,” said Carle.

“The software displays the statistics from the collected data points and gives an overview of the accuracy and precision for each of the tested volumes. ​

“It will send an email to the laboratory manager that A) this pipette has been tested and B) the report is attached or available for review and then ask the laboratory manager to log in to the software and approve or reject that calibration data. ​

“By doing so it allows for a streamlined workflow, you don’t have to print out paper calibration reports anymore, hand them around for signatures or file them in folders so for audits everything is electronically retrievable.”​

Customers benefit from the ability to check pipettes at any time when they suspect anything problematic or if a pipette drops off a lab bench onto the floor.

“Nothing may have been broken but maybe something internally get damaged, it is definitely good practice to check out the pipette in these cases,”​ said Carle.

“The other advantage is the user can calibrate and check the pipettes in the exact lab environment in which they are being used so they don’t have to send it out to a calibration lab and encounter the risk that pipettes might get damaged in transit. ​

“A good laboratory manager will also perform a so-called calibration verification – if they are sending out pipettes to an external calibration laboratory they will verify the calibration results once they have been returned and our instrument is suitable for such calibration verifications.”​