Fully Automatic Application

If you have to perform assays by quantitative TLC, you will find fully automatic sample application indispensable. This will at least require the Automatic TLC Sampler (ATS 3) of CAMAG (Fig. 34), in which a PC controls the application and then, in combination with a TLC scanner, the evaluation. The PC also processes the measured data. The samples are applied from a steel capillary, which is connected to a dosing syringe driven by a stepping motor. The samples are applied to precoated layers (on glass or foil), up to the 20 x 20 cm format, either spotwise or bandwise as required. Applica- 

The sample vials, which are closed with normal septa, are placed in the equipment in a rack with 16 positions. Within one application program, up to 32 vials (in two racks) can be addressed. 

The arrangement of the samples on the layer can be for normal, double-sided, circular and anticircular chromatographic development. 

The Automatic TLC Sampler (ATS 3) is fast. The capillary from which the samples are dosed moves with a lateral velocity of 25 cm/s according to the plotter principle. The dosing rate selected can be in the range 10-1000 nl/s [37]. 

Practical Tips for working with the AS 30 in fully automatic mode  

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A specially modified sampler for Desaga expands the TLC-Applicator AS 30 into a fully automatic application system. The applicator control of the autosampler is performed by a serial interface, and it monitors the selection of sample containers, the delivery of the necessary amount of sample, and the rinsing processes. A second serial interface allows the application parameters to be documented using a printer or laboratory computer system. 

Before purchasing equipment for semiautomatic or fully automatic application, it is advisable to test its performance oneself. Good information can also be obtained from congresses such as the Internationale Symposium fiir Planar-Chromatographie which takes place every 2 years in Interlaken (Switzerland) and exhibitions such as InCom, Diisseldorf (annually), Analytica, Munich (every 2 years) and Achema, Frankfurt (every 3 years). 

The amount of process plant that can be defined accurately as automatic is relatively small, and manual intervention is often involved at some stage. The relevant design criteria are therefore often IM/12 or IM/18. In practice, fully automatic burner controllers tested and certified by British Gas are available that comply with the requirements of BS 5885. Although these have features which may not be applicable to non-automatic plant, it may be more appropriate to use such a controller, particularly as its safety is well proven. It may also be less expensive than buying and installing separate timers, relays, etc. For some processes (for example, those that do not need and cannot tolerate a long purge) such controllers may not be appropriate. 

The wide application of hydraulic systems has undoubtedly been stimulated by the increasing use of fully automatic controls for sequences of operations where the response to signals must be rapid and the controls themselves light and easily operated. These needs are met by hydraulic circuits that, in addition, provide infinitely variable speed control, reversal of high-speed parts without shock, full protection against damage from overhead and automatic lubrication. 

The top and the bottom x-ray detector each contain a multiplier phototube coated with phosphor. This tube compares the intensity of the x-ray beam entering the detector with that of the light from the reference standard, a discharge lamp. The reference beam is part of a circuit that maintains the x-ray source at constant intensity. The deviation wedge comes to rest when the intensities of the transmitted x-ray beams stand in a predetermined ratio. At this point, the unbalance in the servo system has been compensated, and the position of the deviation wedge consequently indicates the thickness of the strip. In 1955, this application was made fully automatic that is, the unbalance (or error signal) just mentioned was used to readjust tandem cold reduction mills of the United States Steel Corporation. Automatic control proved significantly more effective than manual control. 

A second fully automated device, the HPTLC applicator AS 30 (described earlier), can be employed in connection with a sampling device. Automated refilling of the syringe is performed by editing a volume factor, e.g., 10 for application of 10 times 100 pi. This device can be recommended if loss of sample is not relevant (e.g., owing to automatic rinsing operations that afford at least 70 pi dead volume for a minimal 20-cm tube connection). However, the fully automatic mode is not recommended for valuable samples. Sample volume still present in the Teflon tube between the sampler and AS 30 syringe will be wasted and lost because this operation cannot be circumvented by the user. 

High Rate Detonator Production Study. As part of the overall program to modernize the US Govt owned, company operated, Army Ammunition Loading and Assembly Plants, it is planned to develop fully automatic equipment to manuf nonelectric detonators at the rate of 1200 per minute. The survey of literature sources and industry was undertaken to discover techniques and equipment that may be applicable, as described in Ref 1... 

Security sealer. For automatic application of preperforated polyvinyl chloride tubing. The security seal is fully and evenly shrunk around the cap by the heat tunnel. The shrink seal covers the shoulder of the cap to the neck flange of the container. 

Moisture-Based Adhesives. The thin film of moisture-diluted adhesive applied costs very little per 1000 labels, plus labor costs. Plain paper is most widely applied to glass, but can be applied to metal, particularly in the form of a complete wraparound label. Application can be by hand, semiautomatic, or fully automatic methods. Speeds of 1000 or more per min can be achieved. 

The advances in ion exchange analytical methods have also had limited application in some laboratories. Chromatographic and ion exchange methods of purification and identification of trace components in body fluids have occasionally appeared in clinical chemical literature. The development of fraction collectors and even the fully automatic amino acid analyzer are outside the scope of this presentation. 

Camag Automatic TLC Sampler 4 (ATS4) is a precise and fully automatic sample applicator for TLC (Fig. 

If the slide is ready to receive the sample, a green lamp lights up at the DTSC module (Fig. 18) and a beep is emitted. 10 pi of the sample is now applied by means of the electric air displacement pipette. Application of the sample is monitored by an automatic sample detector system. After successful application of the sample the slide travels fully automatically to the pre-incu-... 

Operating Labor Centrifuges run the gamut from completely manual control to fully automated operation. For the former, one operator can run sever centrifuges, depending on their type and the application. Fully automatic centrifuges usuaUy require little direct operation attention. In most production environments, PLC- or DCS-based automatic controls are the norm. 

Tower Presses This press is similar to the stacked horizontal diaphragm presses, but only one filter belt is used (Fig. 18-191). The operation is also fully automatic. The primary applications are in chemical, mineral and pharmaceutical industries. The testing method is the same as the diaphragm presses. One important factor in designing a tower press is the sohds need to be able to be cleared from the chamber sed, otherwise leakage will occur in the following filtration cycle. 

The general text in the main part of these guidelines may be applicable to validation and qualification of premises, equipment, utilities and systems, and processes and procedures. More specific principles of qualification and validation are addressed in the appendices. Semi-automatic or fully automatic clean-in-place (CIP) systems and other special cases should be treated separately. 

Peel-and-stick labels provide a quick and easy way to apply labels to almost any surface. Die cut and supplied on release papers, they can be printed in computers for addresses, while preprinted labels for an enormous range of applications, particularly difficult substrates such as polyolefins or cold, moist containers make labeling a pleasure compared with traditional wet-applied systems such as dextrines or caseins. Pressure-sensitive label stock provides reliable bonding, is easy to use and virtually instantaneous, and offers a choice of properties, including permanence or easy removal, high-temperature resistance, or low-temperature flexibility. Large or small labels can be easily stored and handled, and applied by hand, hand-held applicators, or semiautomatic or fully automatic industrial labelers. 

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