Fig. 1a: Pipette tip connector between serological pipettes and suction tubes.Photo credit: Andy TayLab supplies such as pipette tips and conical tubes are two of the products scientists, especially biologists, will encounter in their careers and use almost daily. Interestingly, while they were designed for specific applications such as aspirating or holding liquids, researchers have found out-of-box (and ingenious) applications for them. Such an exercise of creativity often leads to higher research productivity, cost savings, and convenience.
In this article, the featured lab supplies are our favorite pipette tips and conical tubes. Hopefully, it can also inspire other creative use of lab inventories.
Let’s pick up some (pipette) tips
Walk by any biosafety cabinet, and you will see a suction tube used to aspirate liquids into a waste bottle. This is a step that is typically performed using a serological pipette attached to a tube whose suction is provided by a vacuum flask. Unfortunately, serological pipettes and suction tubes from different manufacturers can come in incompatible diameters. Fear not, you can count on pipette tips to solve this problem!
Fig. 1b: Pipette tip picker for a single colony of bacteria.Photo credit: Andy TayConnector: The conical shape of pipette tips allows them to be a cheap connector between serological pipettes and suction tubes of any reasonable diameters (Fig. 1a). This reduces the need to purchase customized connectors. It also gives your lab the freedom to purchase serological pipettes and suction tubes from any company.
Picker: Pipette tips are also extremely useful for picking bacterial (Fig. 1b) and stem cell colonies with minimal cross contamination. For many microbiology and stem cell experiments, it is important to pick just one single colony to ensure that the bacteria and stem cells you are working with are of the same genetic composition. Pipette tips, with their small, pointed tips, can easily pick up a single colony before subsequent culture.
Fig. 1c: Pipette tip cell scraper for scratch assay.Photo credit: Andy TayScraper: For those of you studying cell migration, do you know that pipette tips are also handy tools to perform the standard scratch assay (Fig. 1c)? In this assay, cells are scratched away, leaving behind an empty region. Cell migration is assessed by monitoring the invasion of neighboring cells into the region. One additional advantage of using pipette tips is that they can be cut at different diameters to create empty regions with different widths.
Hole Puncher: Pipette tips have also been cleverly used in agar gel experiments to test the antimicrobial properties of materials (Fig. 1d). The circular head of a pipette tip is first used to punch out holes from agar gel streaked with microbes. Next, antimicrobial materials are injected into the holes and the hole diameters are monitored over time. The larger the region of dead microbes, the more effective the antimicrobial agents are.
Fig. 1d: Pipette tip hole puncher for antimicrobial assay.Photo credit: Michael ReithoferFiller: Another creative, and probably the least known, use of pipette tips is using them as fillers for thin glass pipettes in experiments in electrophysiology. Currently, polyetheretherketone (PEEK) tubing is used for filling glass pipettes. However, with three simple steps, pipette tips can be transformed into a filler (Fig. 1e)! First, hold a 2-200 μL pipette tip horizontally and heat it at around two-third of its length over a Bunsen burner. Once the plastic starts to melt, use tweezers to pull the melted part vertically downward. Finally, use a razor blade to cut off excess length to get yourself a pipette tip filler.
Fig. 1e: Pipette tip fillers for thin glass pipettes used in electrophysiology experiments.Photo credit: Andy Tay
A 10-foot PEEK tubing, which is sufficient for 40 × 7.5 cm filler, costs ~USD 75 whereas a bag of 960 pipette tips costs only ~USD 24. True, it may take some time to master creating the perfect pipette tip filler, but the effort can certainly save your lab a significant sum of money over time.
And now, conical tubes and their Styrofoam packaging
Left to right: Fig. 2a and Fig. 2b: Conical tubes as marker holders.Photo credit: Andy TayMarkers are frequently used in labs for writing, drawing, and labeling. Have you experienced losing markers and later finding them in random drawers, or in someone’s lab coat days later? Although conical tubes were designed for holding liquids, they have found an exceptionally useful alternative role as marker holders in many labs! With the aid of adhesive materials like plasticine, conical tubes can be attached to nearly any surface near whiteboards (Fig. 2a) and biosafety cabinets (Fig. 2b), where markers are frequently used.
Conical tubes are often delivered to labs arranged nicely on Styrofoam. As Styrofoam is composed of 95% air, it is unsuitable for recycling because it takes up lots of space in bins. One creative use of Styrofoam packaging is as a rack for storing used conical tubes (Fig. 2c). In this way, it stops people from fighting over racks, promotes bench neatness, and reduces environmental waste. What a way to kill three birds with one stone!
Styrofoam rack for storing used conical tubes.Photo credit: Nina ChangMany of you might not have realized how creative you can be when it comes to creating alternative uses for common lab supplies.
Do you have a story to share? The editors at Lab Manager would love to hear it. Simply submit a 40 to 50-word description along with a photo of an innovative use of a lab inventory item to Pam Ahlberg at firstname.lastname@example.org for inclusion in a future article on this topic.