Coffee and E. coli

Out of all the equipment used in chemistry and biochemistry, one piece of machinery can be counted upon to be present in every lab, nearly without fail. This machinery is of course a standard coffee maker, which is used for a daily minimum of two dozen cups of coffee in this laboratory setting. This usage creates waste, including empty coffee containers, usually of the plastic variety. Here, we show the use of different coffee containers as a waste bucket for pipette tips, centrifuge tubes, or other lab materials.

Standard 3-lb and 1.5-lb Folgers coffee containers were found to be very effective, (Figure 1) with the 3-lb containers being of sufficient height to hold long serological pipettes. The 1.5-lb containers, while very useful, have the same base and lower height, making the disposal of top-heavy objects problematic.

Figure 1 - 3-lb coffee container used for waste

These Folgers containers also are made of a recyclable plastic, ensuring the easy disposal of the disposal apparatus when the disposal of other disposable objects is complete. This composition also allows for quick and effective cleaning with organic solvents and bleach.

Classic Roast coffee containers of a medium-roast variety were investigated, but results give no indication that dark roast or medium-dark roast containers would have variance in performance. In the context of a research laboratory, mild-roast containers were found to be completely and totally irrelevant.

Metal coffee containers of the Sam's Club variety were investigated in this report, but found to be ineffective due to their propensity to corrode. This is due to a number of liquids being present in the waste container, either because of direct user input, or leakage of other waste materials. When cleaned with bleach (as is protocol in a biochemistry laboratory) the corrosion and remaining biological material react, creating hazardous fumes as well as an unpleasant foam. To avoid this, a plastic bag may be placed inside the container. Their positive qualities, however, include a heavier weight which allows for the disposal of larger serological pipettes without the canister tipping over, as well as a satisfying *ping* sound when disposing of smaller pipette tips.

In conclusion, we can safely recommend the usage of plastic coffee containers as disposal units for pipette tips and other waste materials.

Pipette Tip Uses Continued

Previously, Inventive Laboratory Practices investigated alternative uses for Rainin pipette tips in a laboratory setting. This has sparked correspondence from other labs, and in collaboration with Dr. Bonnie Barrilleaux at UC Davis, we wish to present an updated list of pipette tip uses.

Figure 1 - Rainin P1000 tip used as an autoclavable sheath for forceps

• P1000-sized tips can be readily used as autoclavable sheaths for items like tweezers, forceps, and scissors. This allows continued sterility of the item, while also protecting delicate ends from damage (Figure 1)
• Larger tips can again be used as adapters to connect Pasteur pipettes to vacuum hoses, allowing easy connect / disconnect of the Pasteur pipette, while maintaining a secure seal. (Figure 2)

Figure 2 - Closeup of connection between glass Pasteur pipette, plastic P1000 tip, and rubber vacuum hose

• We also report that these tips can be used as quick, sterile scoops for small amounts of reagent. This is especially true for reagents that are A) difficult to deal with by hand, such as sodium hydroxide, or B) easily damaged by tweezers, such as protease inhibitor tablets.

Investigation into these useful lab items is still underway. For correspondence, please contact soopaflysa@gmail.com. 

Thanks to UC Davis Postdoctoral Fellow Bonnie Barrilleaux for the tips! (pun very intended)

Falcon Tubes - Not Just For Liquids!

Falcon-brand centrifuge tubes are a convenient, sterile, and disposable way to store chemical solutions and other liquids, and are conveniently manufactured to fit into a number of commercially available centrifuges. This has led to their widespread use in laboratory environments, especially those of a biological nature where sterility is desired. Herein, we report alternative uses for these pervasive laboratory doohickies.

Here we use both 15 mL and 50 mL Falcon tubes for a few things, but far and away the most helpful alternative use is for simple storage. Oftentimes these tubes are used to make Tris buffers, or something equally as harmless, and then simply thrown away. Instead, we use these tubes for storage of small things that are easily lost or separated, such as screws for shaker flask holders (Figure 1) or paperclips.

Figure 1 - Shaker flask holder screw storage. (Reading that aloud makes no sense at all)

We also use these tubes for sonication of cells after hacking off the top. (Figure 2) This allows the "big tip" of our sonicator to fit near the bottom of the tube, maximizing exposure to sonicating waves. By cutting off the tube at the 30 mL mark, approximately 25 mL of cells can be effectively sonicated at a time while minimizing the risk of spillage. This also allows the user to keep subsequent rounds on ice to chill while sonicating samples.

Figure 2 - Sonication apparatus

Finally, we also use these tubes for the simple, but constant need to store pens. Falcon tubes can be especially effective because of their ability to be mounted (taped) in almost any location. This is helpful for two primary reasons. Firstly, it allows pens to be placed at the ready wherever the user desires. Secondly, it allows the user to place pens and other writing utensils in a "hidden" location, such as underneath a benchtop, so that other lab members don't easily find and steal them. (Figure 3) Unsupported data shows that 64% of lost productivity in a laboratory is a result of some jerk stealing your pen right as you need to write down a result.

Figure 3 - Pen holder, conveniently placed underneath shelving

In conclusion, we find that Falcon tubes are useful for many things other than centrifugation techniques, and will continue the investigation into their application to alternative methods.

Please address correspondence to soopaflysa@gmail.com

In which a biochemist uses a fume hood

Acrylic labware is used in many laboratories, in many different fashions. Some experimental apparatuses are made of acyrlic thermoplastics, but in this laboratory setting they are mostly found in sinks, washing areas, and drying racks. (Figure 1) One of the unfortunate coincidences of this placement is that acrylic thermoplastics often come into contact with organic cleaning solvents such as ethanol. Upon contact with ethanol, acrylic labware has a tendency to crack and become distorted, often ruining its usability. (Figure 2) Here, we report the use of the organic compound chloroform to repair these lab apparatuses through liberal application and clamping of the broken acrylic labware.

Figure 1 - Acrylic Drying Rack and Washing Area

Figure 2 - Broken Acrylic Drying Rack

Saftey and Precautions
Chloroform is a known toxic agent, with vapors causing dizziness, headache, and fatigue. All uses of chloroform should be in a fume hood with proper ventilation, as well as proper eye protection and gloves. Don't drink this stuff.

Materials

• Something broken and acrylic - cracks are easiest to repair, with shattered materials becoming more difficult as the complexity of assembly increases.
• Pipette and tips to deliver chloroform to acrylic (P1000 used here, other methods may be more feasible depending on the repair
• Chloroform (Sigma, ACS Grade)
• Tape and / or clamps 
• Paper towels.
• Gloves, goggles, and other protection

Procedure

Figure 3 - Closeup of Broken Rack

Firstly, the rack was removed using a standard Phillips screwdriver and examined. (Figure 3) Then, using sheer force, the cracked areas were re-formed as best as possible, squeezing until an approximate reformation of the original shape was obtained. Help was requested from other lab members, but not delivered. Next, using tape and / or clamps, the cracked areas were secured in this conformation so that upon the release of force, no shifting occurred. (Image not shown due to the difficulties of operating a camera, tape and chloroform in a crowded fume hood) Next, using a P1000 pipette, small quantities of chloroform (< 1 mL at a time) were gently delivered into the crevices, allowing all interacting surfaces to be sufficiently exposed to chloroform. After leaving for lunch and eating a chocolate shake, the clamps and tape were removed, and the structural integrity of the repair tested, and the acrylic labware replaced using the same standard Phillips screwdriver.

Results

Our initial conclusion from this experiment is that chloroform can indeed be used to repair broken labware, but that the method has flaws, and sufficient technique is required. Firstly, the nature of acrylic does not lend itself to perfect repairs, and some gaps / angles remained after the joining of breaks. Secondly, the spreading of chloroform onto other surfaces near and far from the original repair resulted in marred acrylic, which damaged aesthetics but not functionality. This could be remedied by steadier hands, a more thorough tape / clamping job, as well as a more functional workspace. OR HELP FROM OTHER LAB MEMBERS. (Figure 4)

Figure 4 - Repaired Acrylic Labware

While sturdy, and certainly repaired, the structural integrity of chloroform-welded acrylic labware does not match that of the original, unbroken labware. Upon addition of sufficient force to the repaired area, the crack was re-introduced, but the damage was limited to that of the original repair. This test-induced crack was repaired utilizing the same methods listed above, and not tested again, but rather just put back where it belonged.

Conclusion

In a functional laboratory environment, chloroform can be used to repair broken acrylic labware with good reproducibility and success. Care should be taken both for the aesthetics of the repair, as well as for the inherent dangers of using toxic chemicals. In conclusion, we report that our washing area no longer drips water everywhere, and that unnamed colleagues should be more careful when spraying ethanol everywhere, Jon.

Correspondence should be addressed to soopaflysa@gmail.com 

Thanks to forums user OnceIWasAnOstrich for this idea.

Rainin Pipette System Uses

Rainin pipette reloads, while convenient, build up a quick excess of refuse that has no immediate use. Due to their interesting color, shape, and design, this buildup of plastic requires a further investigation into their uses, so that laboratory contribution of non-biodegradable plastics to landfills and other trash collections can be minimized. Here, we report an initial use of these pipette reloading racks, and speculate on other methods of utilization.

Figure 1 - Rainin Pipette Tip System - Pictured are the components of the Rainin Pipette System - from left to right - (1) Reload "punch rack," (2) assembled and autoclavable tip box, (3) left over tip reload rack.

This laboratory uses three (3) types of pipette tips, coordinated by color. Blue corresponds with P1000 (100-1000 uL tips), as green and red correspond to P200 (10-200 uL) and P10 (1-10 uL), respectively. Pipette tips in and of themselves have a myriad of uses, but this extrapolation deals with the reloading system, and the waste it creates.

Details and Measurements
Each rack reload measures 11.75 x 8.15 cm, and (very) approximately 0.10 cm thick. Red and green reloads have an 8x12 grid of holes, each with a diameter of 0.5 cm, while blue reloads contain 0.7 cm holes in the same 8x12 grid. 

Uses!
Waste reload racks have been utilized in the following ways in this laboratory.

Figure 2 - Pipette Reload Use - Colorful key identifier, helps to ensure easy access to keys as well as prevent lab members from just sticking them into pockets

• Gluing multiple reloads together as a microcentrifuge tube rack.
• As a colorful key identifier. (Figure 2)
• Water bath flotation devices for microcentrifuge tubes. (some flotation may be required)
• As a ruler, after making markings using an actual ruler

Further investigation into the uses for these common lab items is still underway. Correspondence should be addressed to soopaflysa@gmail.com . 

Starting With the Obvious

Pipette tips are a ubiquitous feature in most laboratories, especially those in the biological sciences. They have a number of useful applications other than their intended function. Herein, we demonstrate just a few of the many ways these common lab items can be utilized.

Figure 1 - Wash Bottle Nozzle - A single Rainin P1000 tip, attached to the spray outlet of a standard laboratory wash bottle. This serves to direct and accelerate the flow of water from the bottle.


Pipette tips, due to their useful size, can be implemented in a number of ways, including but not limited to:

• Connectors to link rubber tubing together (works best if you cut off part of the tapered end)
• Box openers to rip through tape (200 uL tips work best)
• TLC plate spotters (10 uL tips are recommended, but unverified)

Further investigation into the uses for pipette tips is still underway, and submissions are welcomed.

Correspondence should be addressed to soopaflysa@gmail.com