Termovap-Sample Concentrator TV 10

 TERMOVAP TV 10 SAMPLE CONCENTRATOR

• Concentrating with temperature control and gas introduction above solution surface
• Simultaneous treatment of up to twelve samples
• Gas supply to each vial equipped with a valve
• Easy to handle
• Time saving

A method of concentrating dissolved samples by solvent evaporation using introduction of controlled gas flow (air by means of a pump, nitrogen through a control valve of a gas cylinder) above the level of the solution with temperature control is now still more used technique than conventional alternative procedures, e.g. using vacuum rotary evaporators or Kundera-Danish concentrators.

Concentrating of samples is widely used in combination with solid phase extraction (SPE) in analyses of environmental samples (determination of polycyclic aromatic hydrocarbons, biphenyls, chlorophenols, pesticides, etc.), samples of biological materials, screening determinations of pharmaceuticals, etc., particular lyusing chromatographic methods (HPLC, GC, TLC). In many determinations the method of concentrating dissolved samples forms an integral part of standardised (e.g. determination of polycyclic aromatic hydrocarbons to ČSN 75 7554 standard), unified or recommended analytical procedures and applications.

In comparison with the above mentioned alternative methods it makes possible easier sample handling and especially simultaneous treatment of up to twelve samples. It is a convenient development of a 12-position Dorkus vacuum separator (Tessek, Prague) widely used in the Czech Republic, utilised for extraction of analytes from solutions onto a solid sorbent, or similar imported devices.

The concentrator consists of an aluminium block for twelve 5 ml or 10 ml vials with an adjustable height gas supply. Gas is ducted above the solution surface in a vial using a switching valve and a needle. The block is located in a temperature controlled oven permitting temperature setting from ambient temperature up to 100°C. The oven is heated with an electric heater and a high precision of temperature control is provided by built-in platinum thermal sensor. Actual block temperature is displayed on a 3.5 digit display. A reversible thermal cut-out is built in the instrument, which switches the heater off and transmits an acoustic signal, when set temperature is exceeded by 10°C.