Sample carousel

Fig. 17.8. Representation of a CE system. (1) Electrolyte compartments, (2) the capillary, (3) detector, (4) power supply, (5) sample carousel, (6) electrodes, (7) thermostatted areas and (8) data workstation.

FIGURE I Representation of a CE system. I electrolyte compartments, 2 capillary, 3 detector, 4 power supply, 5 sample carousel, 6 electrodes, 7 thermostated areas, 8 data workstation. 

When attempting to convert a manual method into an automated method, there are certain elements, such as tablet size and solvent selection, which will have an impact on the ease of the conversion from manual to automated. For instance, some of the elements of an assay method that would make it easier to automate would be that the dosage form fits into a test tube the extraction uses neutral media or acid not more concentrated than 0.1 M makes use of nonvolatile, low-toxicity solvents does not use surfactants and uses premixed, room-temperature solvents. Some of the elements of a dissolution method that would make it easier to automate would be that the dosage form fits in the sample carousel, does not use media more concentrated than 0.1 M acid, does not use isopropanol or surfactant in large quantities, uses magnetic sinkers or no sinkers at all, and uses no or minimal reagent addition volumes for pH control. 

Three grams of each sample were placed in 40 mL Pyrex vials with silicone caps and then introduced inside the automatic sampling carousel of the electronic nose. After an equilibration time of 20 min at room temperature, the measurement sequence started with an incubation of 40°C for 10 min. Each sample was evaluated three times and the average of the results was used for subsequent statistical analysis (PCA and ANN). 

LECO CORPORATION X Automated system with sample carousel... 

Figure 7 Automated resistively heated filament pyrolysis using quartz sample tubes, front view, and side view of the pyrolysis chamber. 1, Quartz tubes 2, sample carousel 3, optical sensor for locating tubes 4, funnel to guide tubes into inlet valve 5, inlet valve 6, quartz chamber 7, heating filament 8, outlet valve 9, GC online valve 10, connection to GC injector.

The injection system should be able to inject a small sample aliquot with precision, with injection volumes usually varying from 10 to 200 /uL. The pol5uner sample solutions are commonly prepared with concentrations varying from 0.05 to 0.1% wt/vol. For high temperature SEC, polymer solutions are generally prepared directly in the inj ection compartment imder spinning and filtering, if required. Offline sample preparation setups are also available. The sample injection systems are provided with a sample carousel to permit the sequential injection of several samples. 

Most chromatographs today are sold with autoinjectors. Such units are capable of injecting samples into the LC from vials on a sample carousel or from microtiter plates. They usually contain sampling loops and a syringe pump for injection volumes from less than I pL to more than 1 mL. Some have controlled-temperature environments that allow for sample storage and for carrying out derivatization reactions prior to injection. Most are programmable to allow for unattended injections into the LC system. 

During the extraction cycle, the cell is removed from the sample carousel and sealed at both ends by the autoseal arms in the oven. The pump fills the cell with... 

About 15 mg of the sample of interest, usually a polymer solution or polymer mixture, is forced into a thin-walled glass capillary cell of 1 mm inner diameter. This cell has one lens-shaped end and after being filled with the sample of accurately known polymer concentration or ratio, the other end of the cell is sealed under vacuum. The cell thus obtained has a length of about 25 mm which allows it to be mounted in the sample carousel of the PICS apparatus, where four samples can be analyzed... 

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