Product presentation-1-

Product concept!

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PA301 is a photoacoustic FTIR
accessory that can be used for themeasurement of solid, liquid andsemi-solid samples
PA301 detector improves laboratory
productivity and safety by enabling
extremely versatile and rapid analysis
of solid and liquid samples in any form
without sample preparation
PA301 is utilizing Gasera’s patented
cantilever based optical microphone
technology that provides ultra highsensitivity-2-

UsageInstall PA301 in to thesample compartment

Measure Carbon Blackreference

Run spectra andAnalyze results

Seal the chamber formeasurement

Insert sample into
the sample cup

Slide in the sampling sledge-3-Photoacoustic detection!
Focusing mirror

Optical cantilever
microphoneCantileverSample in a cup!

Photoacoustic spectroscopy directly measures asample’s infrared absorption. The absorption ofinfrared radiation in the sample creates heat which istransferred into the surrounding gas and aphotoacoustic signal is generated via thermal
expansion
The expansion of gas is then detected with acantilever pressure sensor

Photoacoustic cell

Thermal diffusion length limits the samplingdepth with optically transparent samples.
Depth is limited by L.

Light intensity decay in a strong
absorbing sample.
Depth is limited by 1/α

IRTLight intensity decay ina transparent sample,
α2 << α1-4-Ultra sensitive opticalcantilever microphone!

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The heart of the system is the patented
optical microphone comprising of a MEMS
cantilever coupled with a laser readout
interferometer
It is capable of digitally measuring
microscopic movements of the cantileversensor, having a dynamic range greater than
any analog circuitry can ever obtainΔx [m] Δp [Pa] ΔT [K]Δm [g]

2 x 10-12 2 x 10-7 2 x 10-9 4 x 10-12
With 1s measurement time.

-5-PA301 Performance!
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Due to the ultrasensitive cantilever microphone, the SNR of PA301 is ten times higher
than with other photoacoustic detectors using condenser microphone.
This means that same SNR is received in 100 times shorter time scale.
It also means that equal SNR without helium purge is still achieved 10 times faster.
Cantilever microphone also does not lose its performance over the time.

Reference PAS
100 scans

Cantilever PAS100 scans

SNR = 133

SNR = 1370

Reference PAS
1 scanCantilever PAS
1 scanSNR = 13

SNR = 137

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Versatility! PA301 can measure any kind of samples
with minor or no sample preparation! The spectra can be used for qualitativeand quantitative analysis of samples! Commercial transmission spectrum
libraries can be used for material
identification! PA301 can be connected to nearly any
existing FTIR device-7-Easy sampling!
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Insert sample to the cup, slide the cup inside thePA301 and press measure.
No sample preparation is needed. The only
requirement is that sample fits into the samplecup (10 mm in diameter and 9 mm in height)
Sample is not pressed, grinded, dissolved, mixed
with KBr or even contacted.
Samples are not consumed, which saves
valuable or delicate samples.
Sample cups are replaceable and washing up
can be avoided.
Helium purging is made easy with, no external
flow meters are required-8-Normalization
Sample spectrum!

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Sample spectrum is divided with acarbon black reference spectrum,i.e. normalized
This cancels out the instrument
contribution from the spectraNormalized spectrum
Carbon black spectrum-9-Purging! The sample space canbe purged with N2/He
in order to remove
H2O vapor and carbon
dioxide! Helium purging
increases the signal bya factor of 2-3- 10 -

Insensitive to sample
morphology
Broken tablet

Fine ground! Makes sampling easy
! Makes quality control
easy! Fibers, single particles,powders and large solid
samples can be directly
measured- 11 -

Depth profiling!
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coated tablet

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Depth fromthe surface

Depth varying information can be obtained with photoacoustic spectroscopy.
Depth scale is selected by varying the mirror velocity or modulation frequency in
the FTIR interferometer and phase of the spectra.
It is possible to vary depth from range of below 1 µm to few hundreds ofmicrometers.
Spectra from different depth ranges can be measured.
Depth of different layer interfaces can be determined.
Distance between different layers can be determined with higher resolution byusing the phase data.
Spectra from two different layers can be separated from each other.

Layered sample

Spectrum of the layerSample surface
Coating layer

Medicine layer- 12 -Application: Black samples
Bitumen!

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Heavy fuel oil!
Deposit from heatexchanger!

PAS suits extremely well for themeasurement of dark samples that have
low transmittance or reflectivity on a wide
spectral range.
The reason for this is that PAS is a directabsorption measurement technique – thehigher the absorbance the higher thesignal.
With other techniques (transmission, ATR,DRIFT) proper spectra are difficult toobtain from dark samples due to the highabsorption.
With PA301 accessory no sample
preparation is needed and contaminatedsample cups can be discarded after theuse.

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Application: Soil and mineral samples
Ca,Mg carbonate!

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Clay soil sample!

PAS is an advantageous method
for the measurement of soil andmineral samples
since it iscontactless measurement andinsensitiveto
thesample
morphology.
In PAS, no sample preparation isneeded such as for example
mixing with KBr in diffuse
reflectance.
Mineral samples typically have avery hard surface, and therefore, aproper optical contact is hard toobtain with ATR method even witha diamond ATR.

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PAS, ATR, transmission and diffuse
reflectance intercomparison!

ATR vs. PAS!
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DRIFTS vs.PAS!

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Non-deformable solids give weak signals with ATR because of bad optical contact.
PAS is extremely good with hard and optically opaque samples which are not suitablefor ATR.
PAS can measure any samples with any shape or morphology while ATR might
destruct the sample.
Short sampling depth, e.g. emulsions do not give representative results. PAS hasvariable sampling depth.
Cantilever PAS has better sensitivity than DRIFTS with any kind of samples. Samplesof diffuse reflectance often need to be powders or even mixed with e.g. KBr, because
spectrum is a combination of transmission and reflection spectra.
PAS has simple optics that does not need basically any adjustments after initiallyattached to the FTIR interferometer, while in DRIFTS sample or mirrors have to be
regularly adjusted.

Transmission vs. PAS!
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With PAS the sample preparation is very minimal while with transmission method thesample preparation takes huge amount of time and may require many toxic materials.
Transmission measurements are difficult with optically opaque samples.

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Other typical applications
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Dark samples (eg. bitumen, rubber, heavy oil, etc.)
Study of carbons, coals, hydrocarbons, hydrocarbon fuelsCorrosion
Clays and minerals
Wood and paper
Polymer layers
Food products
Biology and biochemistry
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Medical applications
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e.g. Proteins
Bacteria
Fungi
Human tissue
Drug characterization and penetration
Teeth, hair and bacteria

Nondestructive measurement of carbonyl compounds,
textiles, and catalysts- 16 -

MADE TO MEASURE.

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