Introduction

The invention proposes a buffer for sampling a liquid to perform its chemical-physical analysis. In particular, the buffer prevents the contamination of the samples collected consequently and permits simultaneous sampling and measurement. In conclusion, the integrated device for on-line and in-situ environmental monitoring, can provide reliable measurements at higher frequencies.

Technical features

This buffer allows to store and distribute a predetermined quantity of liquid using only a small amount for the cleaning process. For this purpose the device is provided with a variable volume chamber, during the cleaning phase it is minimally expanded. The buffer, used in on-line and in-situ systems with electrolytic, electrochemical and immuno-sensors, decouples the liquid uptake and measurement operations of the substances contained (eg pollutants). This allows the integrated system to start the following sampling process while the measurement is still underway reducing waiting times and thus increasing the frequency of the measurements. The buffer has to be inert and non polluting material, compatible with the liquid to be analyzed (eg polytetrafluoroethylene – PTFE) and has proper mechanical strength. To understand the functioning of the buffer, it is necessary to consider it integrated in an measuring system (Figure on the side). The entire integrated system consists of a buffer, 3 valves (EV1-3), 1 pump (EPMP), 1 inlet / outlet (bottom) and 1 outlet (top) for the liquid. The buffer in the figure can be tilted to meet any mounting needs while maintaining its proper functioning.

Possible Applications

• Sampling and chemical-physical analysis of liquids for environmental monitoring purposes;
• Chemical, biochemical, chemical-physical and biological analysis;
• Water analysis.

Advantages

• Protect analytes from contamination;
• Buffer compatible with sensorized systems (electrolytic, electrochemical, immunesensors, etc);
• Usable on-line and in-situ;
• It allows to decouple the sampling and measurement of the substances;
• It allows to start the following sampling process while measurement is still underway, reducing waiting times by increasing the frequency of measurements.