PTR-MS. PROTON TRANSFER REACTION
ASI are pleased to announce the introduction of their new Compact
System. Designed and Manufactured by Anglo Scientific Instruments this new advanced PTR-MS system
is designed for trace level detection of Volatile organic compounds (VOC's).
PTRMS is a very sensitive instrument for the detection and measurement of trace levels of VOCís. It incorporates a soft ionisation process by producing H3O+ ions from a discharge ion source these are then combined with the sample gas that enters through a separate inlet. The charge from the H3O ions are transferred to the VOCís within the sample that have a higher proton affinity. Normal air gases N2, O2, Ar, CO2 etc have a lower proton affinity and do not become ionised. The VOCís after passing through a drift tube to remove cluster ions are then analysed and detected by the mass spectrometer
Choice of reagent Gas. (Optional)
A wide choice of different reagent gases with different proton affinities can
be selected to suit a wide range of different applications. Either a single
reagent gas facility can be provided or a switchable (up to 5) to aid in
identification of unknown trace VOC's.
A 45mL water container mounted on a temperature controlled panel is fitted as standard.
It will provide approx 100 hours use before refilling is required. It is easily accessible by the user and can be topped up or refilled within a few seconds.
Additional Reagent gases, if required, are contained within small
gas bottles built into the side or front of the system. They are fitted with
'quick fit' connectors that allow easy removal for replacement or recharging .
Compact & Light
This 'Table Top' PTR-MS system measures only
64cm x 36cm x 34cm and weighs from 32
Kgrms (Depending on options chosen) It is the only portable PTR-MS system available
that can be easily transported in the boot of a small car for
field use, and can easily be carried between 2 people for 'On Site' analysis.
Very low Power requirements
The system consumes between 80 -90Watts (Depending on options). This is
only 8% of the power requirements of competitive PTR-MS systems, and is the
only PTR-MS that will also run on a small 24Volt rechargeable battery pack
making it ideal for environmental applications in the field.
The new 'Plug In' discharge Source is easily removable for cleaning or replacement by the user.
The electronics unit automatically adjust the discharge voltage to maintain a constant discharge current irrespective of source pressure or temperature thereby providing a very stable reagent ion supply.
The discharge current can be manually set by the user over a wide range.
The Drift Tube is made from High alumina with a multi layer internal resistive coating that has been fired at high temperature. It therefore has a smooth internal surface that provides clean laminar flow of the sample
gas with low memory efffects. The voltage gradient on the drift tube can be changed from
0V/cm up to 60V/cm.
|The Drift Tube Assembly.
The picture opposite shows the drift tube and the differential pumping
cones fitted to its support flange. The Ion source plugs into the back of
this flange, and is easily accessed by the user. This unit plugs into the
Drift Tube Housing that contains the differential pumping port, and a port
that connects to the analyser housing.
Quadrupole Mass Spectrometer.
ASI have been designing and building quadrupole mass spectrometers for 40 years. The quadrupole analyser was designed specificately to optimise sensitivity and performance for the PTR-MS system.
An optional triple mass filter is available to provide a high sensitivity over the entire mass range, with a choice of mass ranges up to
500amu. A Special off axis electron multiplier has been selected for its high gain performance even at high operating pressures. It can be used for continuous current monitoring or in a pulse counting mode when the highest detection capability is required.
Control of the Mass Spectrometer is direct from a PC Computer and is supplied with comprehensive software for data storage and display.
The PTR-MS system has been designed on a modular basis with easy access for service
and maintenance of key components to keep 'Down Time' to a minimum.
In addition to manufacturing
complete PTR-MS Systems ASI are also prepared to supply the PTR Engine
assembly to companies or research organisations that wish to build their
own PTR-MS systems.
The complete PTR-MS Engine is
briefly made up of the following components:-
1. Plug-in Discharge Ion Source.
2. Drift tube assembly
3. Drift Tube Housing
4 Differential Pumping
5. Quadrupole analyser &
6. Quadrupole Electronic Unit (Not
7. Ion Source and Drift tube
Electronic Unit. (Not Shown).
8. All connecting Cables.
9. Operating Software.
Contact ASI for further details
R & D applications for the PTR-MS System include:-
Food aroma/flavour measurement,
Environmental monitoring & forensics,
Defense/security applications (explosives & their precursors or ingredients, chemical threat agents),
Clinical applications (breath analysis, drug metabolism & development,
Biotech fermentation monitoring,
For sales and further information on
the PTR-MS System or Components Contact :- email@example.com