Pipet tips

A homemade combination scraper-coUector used in my laboratory can be made from a Pasteur pipet (229 mm x 7 mm OD Fisher Scientific Co., Pittsburgh, PA Catalog No. 13-678-6B) [52]. The pipet is cut with a file 60 mm from the top and 65 mm from the tip to produce a pipet that is approximately 100 mm long, which is then plugged with glass wool. The pipet tip is attached to a vacuum pump or... 

Guard column, Betasil Cig, 10 nun x 2-mm i.d. Guard column holder Eppendorf fixed-volume pipets, 0.50-mL Eppendorf fixed-volume pipets, 1.0-mL Eppendorf pipet tips, 1.0-mL... 

Because the PCR exponentially copies the target molecule or molecules, amplicon contamination in the laboratory is a serious concern. It is recommended that the mastermix is prepared in an isolated area, such as a PCR station equipped with a UV light. This work area should be exposed to UV radiation after use to destroy any DNA contaminants. The use of dedicated pipets and Altered pipet tips is also recommended. The template DNA should be prepared and added to the reaction in an area that is isolated from the mastermix preparation hood. The thermal cycling and gel electrophoresis should be conducted in a third work area and care should be taken not to introduce amplified PCR products into the mastermix or template preparation work areas. 

Pipet tips Sorenson Multiflt Research Pipet Tips 5-200 and 100-1000 p-L Rainin Certified Disposable Pipet Tips 10 mL... 

Exogenous sources such as a person s hair or skin, doorknobs, laboratory benches, dust, reagents, thermal cyclers, and pipet tips are some of the common sources of DNA contamination. Ideally, a laminar air flow bench with filtered air provides a clean, dust-free environment. Sample preparation should be done in a separate room or area. The addition of sample to the PCR reaction mixture in the... 

Ribonuclease (RNAse)-free pipet tips (Ambion). 

The interface layer contains contaminants such as proteins, including RNAses, and should not be carried over. To avoid this, the tube is tipped at a 45° angle and the pipet tip carried along the outermost tube wall to be able to pick up the last drop of aqueous solution. 

Method / was designed for an unbonded microreactor. A micropositioner-controlled pipet tip was used to inject the liquid into the channel from the open top of the channel. 

Make sure that there are no air bubbles. I usually place 40-50 pL PCR reaction mix on the top of the coverslips. Invert one slide at a time, touch it to the drop of reaction mix, and quickly lift the slide. The coverslip should remain adhered to the slide because of surface tension. Flip the slide, center the coverslip with a clean pipet tip, and gently remove the air bubbles. 

The unit also has the ability to advance or increment the various test tube and pipet tip holding racks in the programming for automatic sequential operations. Figure 4 gives a typical small program called "Pick up Tube. ... 

Mechanical pipet fillers (sometimes called safety pipet fillers, propipets, or pi-fillers) are more convenient than latex bulbs (Figure 1.4C,D). Equipped with a system of hand-operated valves, these fillers can be used for the complete transfer of a liquid. The use of a safety pipet filler is oudined in Figure 1.5. Never allow any solvent or solution to enter the pipet bulb. To avoid this, two things must be kept in mind (1) always maintain careful control while using valve S to fill the pipet, and (2) never use valve S unless the pipet tip is... 

To use the pipettor, choose the proper size and place a polypropylene pipet tip firmly onto the cone as shown in Figure 1.6. Tips for pipets are... 

Vortex mix the NBT and BCIP stock solutions, and add 100 pL of each to 50 mL AP staining buffer When pipeting BCIP, it is useful to snip off the end of the pipet tip to widen its bore. 

Plastic sandwich boxes make good containers for blot washing, but often have a much larger base area than the size of the membrane. It is useful to have a few containers that have a base of similar dimensions to the membrane, so that incubations can be carried out in as small a volume as possible. Incubations with antibody solutions can be performed in heat-sealed plastic bags (see Note 11), but this is not practical for other steps, particularly incubations with visualization solutions Lids from pipet tip holders make suitable containers for small blots from mimgels... 

Make a series of four to five 100-fold serial dilutions in 2X TY using new pipet tips each time. Plate 100 pL of each dilution on the appropriate selective TYE plates... 

Inoculate individual colonies from the plates of phage-infected TGI spread after the desired round of selection into 150 pL 2X TY-AMP-GLU into 96-well plates. Use a toothpick or a small pipet tip as inoculating device. After inoculation, use the same device to touch a replica 2X TY-AMP-GLU plate with a numbered grid... 

Force a 1 to 200 il pipet tip onto the other end of the tubing and, using a ring stand and clamp, position the tip 0.5 to 1 mm inside the top center of the gel sandwich. Use the clamp to hold the pipet tip firmly in place. 

Supervisors usually assume that novice analysts joining their group know how to use a micropipettor properly. Usually, this is not the case therefore, some suggestions for accurate pipetting of viscous samples involved in (3-glu-can analysis arc presented here. Do not immerse the pipet tip more than 3 mm into the solution. Deeper immersion usually leads to... 

Dry the sample, pipet tips, and the NMR sample tube plug 2 hr in a desiccator under vacuum at room temperature. 

Layer the blood mixture on top of the Ficoll solution using a 10-mL pipet and pipettor. Proceed carefully so as to not disturb the Ficoll-blood interface by keeping the pipet tip against the tube wall close to the blood surface. The Ficoll to blood volume should be approx 2 3. 

Using a 10-mL pipet and pipetor, carefully aspirate the plasma layer from the Ficoll tubes and discard. Leave approx 5 mL of plasma on top of the mononuclear cell layer to avoid cell loss. Carefully aspirate the mononuclear cell layer and transfer to two new 50-mL Falcon tubes. A total of approx 12 mL of the mononuclear cell volume should be obtained. Move the pipet tip in a circular, continuous manner over the mononuclear cell layer when aspirating avoiding red blood cell contamination. Discard the red blood cell contents in to the waste container containing 10% bleach solution. 

Plasticware sterile 35-mm and 90-mm Petri dishes, autoclaved yellow and blue pipet tips, 1.5- and 0.5-mL Eppendorf tubes. 

Wash thoroughly 10 times with TBST. Elute bound phage for 5-10 min with 400 pL of elution buffer. Wash the plate surface thoroughly during this elution using a pipet tip to remove all phage. Add 75 pL of 1 M Tris-HCl, pH 9.1, and mix (see Notes 3 and 4). 

Aliquot 50 pL of the master mix into each well of the PCR plate. Pick large colonies with sterile pipet tips and add to the appropriate wells. 

Fig. 7. Combination of pipet and buret. This combination (Seligson, A. H. Thomas Co.) is usable for multiple microdeterminations in which the sample is first picked up and then diluted. The pipet tip is calibrated to contain samples as small as 50 jil. The sample is quantitatively rinsed out and diluted by a reagent added from the buret.

Dissolve peptide and lipopeptide vaccines in saline to a concentration of 200 nmol/mL. If necessary, encourage dissolution by warming in a water bath and/or by sonication. Do not mix by pipet if the inoculant is not soluble this can result in insoluble peptide or lipopeptide being trapped in the pipet tip. 

Proper reagent care can reduce problems stemming from contamination, heat or excessive light exposure. Reagent contamination can be avoided by the use of clean pipet tips. Prompt return of reagents to proper storage conditions will prolong their shelf life. 

Dilute DNA solution to 1-2 ug/ml. in sterile TE and fill the injection pipet by dipping the end in the diluted DNA solution. Allow capillary action to fill the pipet to several millimeters above the tip. Attach the injection pipet to a second micromanipulator via its instrument tube, and connect the instrument tube to a glass 50-mL syringe filled with air. Insert the injection pipet tip into the injection chamber at a 5-10° angle. Demonstrate that the injector is not clogged by displacing an egg with a stream of DNA solution. 

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