Photoacoustic detector for solid, semi-solid and liquid samples

The INRAe of Narbonne has bought an ultra-high performance photoacoustic detector for solid, semi-solid and liquid samples (a PA301 module produced by Gasera). The PA301 is used as an accessory for any FTIR device. Last week, the Envicontrol team provided on site setup and a full training has been given.

The PA301 photoacoustic FTIR accessory improves laboratory productivity and safety by enabling extremely versatile and rapid analysis of solid, semi-solid, and liquid samples in any form without sample preparation.

The insensitivity to sample surface morphology, the depth profiling capabilities, and contactless measurement provide wide applicability in many areas of chemical and biological research which no other single accessory can match.

Due to the ultra-high sensitivity of the Gasera novel cantilever sensor, high quality spectra can be obtained in just seconds unlike in other available photoacoustic accessories. In fact the PA301 is over 100x faster that other competing PA solutions in the market. Furthermore, ambient air can be used as the carrier gas to obtain a signal-to-noise ratio (SNR) that is still significantly better compared to other commercial photoacoustic detectors used with helium carrier gas.

The quickness and the ease of use make the PA301 a must-have accessory for every lab!

Features

Measures solid, semi-solid and liquid samples.
Insensitive to sample morphology – hard crystalline materials or powders can be easily measured.
Highly absorbing “black” samples are well suited for the instrument due to the photoacoustic measurement principle.
Spectral range from UV to far-infrared.
Capability for depth profiling.
Sample space with the maximum sample size of 10 mm and 9 mm in diameter and height.
Automated purge gas control for nitrogen or helium.
Photoacoustic detector with cantilever enhanced optical microphone.
Patented ultra-sensitive optical microphone based on a MEMS cantilever sensor coupled with a laser interferometer to measure microscopic movement of the cantilever sensor.
Complies with the following standards or other standardization documents under the Low Voltage Directive 2006/95/EC and EMC Directive 2004/108/EC: EN 61326-1:2005, EN 61010-1: 2001
12 month warranty

CANTILEVER SENSOR

High sensitivity is achieved by using a patented cantilever pressure sensor that is over hundred times more sensitive compared to a membrane, which is used in conventional techniques.

Gasera’s patented cantilever-type pressure sensor is designed to significantly improve the sensitivity of potoacoustic spectroscopy (PAS). An extremely thin cantilever portion moves like a flexible door due to the pressure variations in the surrounding gas. The movement of the free end of the cantilever can be about two orders of magnitude greater than the movement of the middle point of the tightened membrane under the same pressure variation. This is because the cantilever only bends and does not stretch.

The sensor is made out of single crystal SOI-silicon with a specially developed dry-etching process that leads to a highly stable component; this is why the sensor is practically totally immune to temperature and humidity variations. In addition, the sensor is not suffering from wearing. The manufacturing process of the cantilever has been developed in co-operation with the Department of Micro- and Nanosciences of Aalto University in the research group of Micro and Quantum systems which is lead by professor Ilkka Tittonen.

READOUT INTERFEROMETER

The displacement of the cantilever is measured optically to avoid the so called “breathing effect”, which occurs in capasitive measurement principle where the other electrode damps the movement of the sensor. For precise measurement of the cantilever movement Gasera has developed a laser based readout inteferometer which is able to accurately measure displacement from well under a pico-meter up to millimeters.

Together the cantilever sensor and the readout interferometer form an optical microphone that has demonstrated over hundred times better sensitivity compared to conventional microphone technology when applied to photoacoustic gas detection.