Automatic pipet

Add 10 ml. of 85% sulfuric acid (preferably by means of an automatic pipet). 

Several methods have been used for the matrix application (1) immersing a tissue section quickly in a matrix solution, (2) spraying matrix solution onto a tissue section with an air brush, (3) putting small droplets of matrix solution onto a tissue section with an automatic pipetting device that can dispense picoliter volumes (lpL = 10 pk) of reagents.4,5,715161819... 

Pipet 25.00 mL of the degassed soda pop into a 250-mL Erlenmeyer flask Set up the titration experiment with pH probe and pH meter on an automatic stirrer. The standardized 0.10 N NaOH is the titrant. 

The analysis takes place in a circular disc called the transfer disc or rotor (Figure 6.1) made of an inert material such as Teflon or acrylic whose surface properties allow minimal adhesion of liquid. It contains radially arranged sets of cavities, each set composed of two or more interconnected cavities, one for the sample and the others for the reagents (Figure 6.2). Small measured volumes of sample and reagent, e.g. 5 - 200/rl, are automatically pipetted into the appropriate wells so that each set contains a different sample but the same... 

Implementation of microanalytical devices presents some issues mostly related to the scale of the volumes. In fact, successive reduction in the sample volume may compromise analysis either because the measurement limit of the analytical method is exceeded or because the sample is no longer representative of the bulk specimen. Another drawback for microchip devices is microvolume evaporation of both sample and reagent from the microchip, compromising quantitative determination or inducing unwanted hydrodynamic flows. This problem has been addressed by designing pipetting systems that automatically replace fluid lost by evaporation or by enclosing the chip in a controlled... 

A comparison of automated pipetting with manual pipetting, by Weltz [16]. demonstrates a difference of approximately one order of magnitude 0.4% RSD for automatic sample introduction versus 3.2% RSD for manual sample introduction. To achieve optimum results for trace elements in biological materials, the use of dedicated automated samplers is recommended. The Hquid-handhng capabihties of a pipetter/diluter workstation have been evaluated at Ortho Pharmaceutical (Haller et al. [17]). Four different volumes of each of three solvents were dispensed 20 times. Actual volumes... 

NMR-tomographic method, any commercially available NMR spectrometer can be used. To inject samples from 384-format deep-well microtiter plates into the bundle automatically, an in-house-developed pipetting robot with a modified tray was used. 

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. ... 

Although most quantitative transfers are now done with automatic pipetting devices, which are described later in the chapter, instructions will be... 

Information on automatic pipets, procedures for use, and helpful hints. http //ehs.clemson.edu/bsm-spil.html Biological Safety Manual. http //www.hendrix.edu/chemistry/chemsafe.htm... 

When the tissue starts to break up, ensure complete dissociation into individual nuclei by pipeting using a 5-mL automatic pipet... 

A clean glass pipet is recommended to deliver the acid, as accidental splashes and fumes from acids can cause corrosion of expensive automatic pipets. 

In general, ELISA tests have been implemented in meso-scale instrumentation based on the microtitre plate format, which has become a standard, very widely spread configuration. The analyses are usually performed with a protocol that enables the thermodynamic equilibrium of the immunoreaction to be reached at each step of the assay. In this manner, the capture efficiency is optimised and the obtained results are often very satisfactory in terms of sensitivity and reproducibility. In order to further increase the performances and throughput of these tests, fully automatic robotised stations have been developed, thereby reducing manipulation errors such as dilution or pipetting imprecision, for instance. 

The authors applied this concept to both gas/liquid (see Figure 3.75) and liquid/ liquid systems (see Figure 3.76). This set-up consisted in the core of a tubular reactor with an interdigital micro mixer as dispersion unit (compare Figure 3.77). The peripheral equipment consisted of an automated pipetting robot, a fraction collector and a gas-chromatograph equipped with an automatic injector. 

Fig, 1. Automatic pipet washer. The siphon principle is utilized to empty the chamber after it has been filled to the preset point. This is a schematic diagram. Many varieties are commercially available,... 

Automation in the pipetting and transferring of solutions has been suggested for many years (see, for instance, Rowe (Rl), 1916). No attempt will be made here to cover the historical developments in this field. Any automatic pipet must supply the positive or negative pressure (with respect to atmospheric pressure) needed to move a liquid from the reservoir into the pipet. This has variously been supplied by such means as hydrostatic pressure, external vacuum or pressure pumps, in... 

Fig. 4. Use of rubber bulbs in automatic pipetting, (a) Propipet. The rubber bulb is supplied with three manually operated ball valves which control the filling and emptying. (b) and (c) Examples of rubber bulbs which are compressed respectively by plunger and lever action (lever, Fisher Scientific Co.).

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