Pipette filler

To use such pipettes, a suitable pipette filler is first attached to the upper or suction tube. These devices are obtainable in various forms, a simple version consisting of a rubber or plastic bulb fitted with glass ball valves which can be operated between finger and thumb these control the entry and expulsion of air from the bulb and thus the flow of liquid into and out of the pipette. Suction by mouth must never be used to fill a pipette with liquid chemicals or with a solution containing chemicals. 

Presently, many analysts make use of pipette filler for sucking in and draining out of liquids from the transfer pipettes for obvious reasons. 

Use a safety pipette filler to draw 10 mL of 6.0M hydrochloric acid (HC1) into a 10-mL graduated pipette. 

Pipette, using a suitable safety pipette filler, 25 ml acid-dichromate mixture into the flask, fit the cold finger dispenser and slowly turn on the water supply. Place on a hotplate and simmer for 2 h. 

Workers should always wash their hands thoroughly on leaving a laboratory and before eating. All pipetting by mouth should be avoided since there are excellent rubber bulb and piston-type pipette fillers available commercially. 

If the end of the pipette indicates the pipette is of blow-out design, gently (but firmly) provide (by lips or by the pipette filler) extra air pressure to blow out the last drop of liquid. Do not maintain a long continuous blow, especially if you are using the mouth to blow out the excess because you may contaminate your solution. 

Spectroline Pipette Filler 26 Nalgene Pipetting Aid Outfit... 

Spectroline Pipette Filler 40 Volac Universal Pipette Controller... 

Spectroline Pipette Filler Arthur H. Thomas Company Vine Street at 3rd P.O. Box 779 Philadelphia. PA 19105 33, 22 D... 

Never mouth pipette any hquid. Use a pipette filler (see p. 10). 

Rinse out pipettes with a little of the solution to be delivered before commencing the accurate measurement. To prevent cross-contamination, never draw the solution into the pipette filler. 

For safety reasons, it is no longer permissible to mouth pipette - various aids (pipette fillers) are available, such as the rubber-bulb and Pi-Pump (Fig. 3.3). 

Fig. 3.3 Pipette fillers (a) rubber-bulb type (b) Pi-Pump . ...

Use appropriate aids such as spatulae, pipette fillers, Pasteur pipettes etc., to minimize risk of contact. 

A clean 25.00 mL pipette (p. 10) is required together with a suitable pipette filler. Various designs of pipette filler are available. The most common type is based on a rubber-bulb suction device. It is best to evaluate a range of pipette fillers, if available in the laboratory, for ease of use and performance. The pipetting procedure is as follows ... 

Using your pipette filler, draw the titrand to just beyond the graduation mark (Fig. 21.3a). Remove the pipette filler, and invert the pipette to allow the solution to drain out. This ensures that the titrand used subsequently will be undiluted and uncontaminated by any residue or liquids in the pipette. 

Pipetting must be done by means of pipette fillers or automatic pipettes never by mouth. 

Whenever you are manipulating glass make sure your hands are properly protected. Be careful when fitting a pipette filler to, and... 

Make sure that the pipette filler is dry and that any solution previously used does not contaminate your sample. Fit it to the pipette and check that it is working properly i.e. it draws solution into the pipette and the pipette does not leak when held vertically. Do not force the filler onto the pipette in trying to stop a leak - the pipette is likely to break and cause an injury. 

Release air into the top of the pipette (with some pipette fillers it is necessary to remove the filler from the pipette at this stage) and let the solution drain naturally (by gravity only) into the collecting vessel. 

Inspect the pipette and the pipette filler. Ensure that the pipette is not chipped and that the filler is clean and dry, otherwise the volume measurements will not be correct. Fill the pipette with water and allow it to drain out. Check that the tip is not blocked and the water drains freely. If the pipette is clean no droplets of water will be left on the sides of the pipette. If the pipette is dirty or blocked, clean it as advised by the laboratory supervisor or select another one that is clean. 

Selecting and keeping particular items of equipment for the job -pipettes, pipette fillers, volumetric flasks. 

Pipettes are used to transfer accurate volumes of solution from a container (usually a beaker) to a reaction flask for dilution or assay, usually in conjunction with pipette fillers. They are not drinking straws and should never be placed in the mouth, or used to mouth pipette solutions. This practice is both dangerous and unhygienic. There are two main types of pipettes. 

Pipettes of this type are used in all analytical chemistry procedures. Care must be taken when inserting the pipette into the pipette filler. If the pipette is held by the bulb and pushed into the filler, the shaft of the pipette can break and the operator can be injured. When inserting pipettes into pipette fillers, the pipette must always be held close to the end to prevent this all too common accident occurring. 

The use of glass pipettes should be avoided if possible and no mouth operations should be allowed. If it is necessary to use glass pipettes, then these should have a small piece of cotton wool introduced into the mouth end and then be sterilised in cans in an oven. With practice, it is possible to remove the lid of the can, shake out the pipettes, and remove one without touching the others. The lid can then be replaced keeping the other pipettes sterile. These pipettes may then be used with a pipette filler. It requires considerable experience to keep these glass pipettes sterile and avoid dropping contaminated liquid during manipulations. Once used the pipette should be placed into a container of disinfectant. 

First, the apparatus is to be cleaned to avoid contamination. One hundred millilitre (polyethylene PE) volumetric flasks, 250 mL (PE) sampling bottles, and tips for pipette filler (polypropylene PP) etc. are all placed in a 5-10 % sodium hydrate solution with ultrapure water for a day, then after cleaning with ultrapure water. 

First of all the capillary is filled as normal with closed ventilation tube as shown in Fig. 3.14a. Afterwards the filling tube is to be closed (Fig. 3.14b), then the ventilation tube is to be opened and slight pressure has to be applied on the capillary tube manually (with a pipette filler for example). The bubbles have to be driven into the ventilation tube carefully so that the capillary is free of bubbles. It is important to assure that the meniscus in the capillary tube reaches the opening of the ventilation tube, but does not fall below the opening so that the bubbles can ascent into the ventilation tube completely. Afterwards the ventilation tube has to be closed and the capillary has to be refilled with bubble free solution from the reservoir... 

A selection of apparatus used In a titration pipette filler, burette and pipette... 

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