DART-Thermo LTQ/Orbitrap Interface Manual For Thermo LTQ (Orbitrap) Velos, LTQ Orbitrap XL, LTQ Ion Trap, Exactive High Performance, and all other instruments that utilize the Ion Max Source Version 20120423 IonSense Inc. 999 Broadway Suite 404 Saugus, MA 01906
Copyright 2005-2010 by IonSense Inc. All rights reserved. The information in this document has been carefully checked and is believed to be reliable. However, no responsibility is assumed for inaccuracies. Statements in the document not intended to create any warranty, expressed or implied. Specification and performance characteristics of the hardware and software described in the manual may be changed at any time without notice. IonSense Inc. reserves the right to make changes in any product herein in order to improve reliability, design, or function. IonSense does not assume any liability arising out of application or use of any product or circuit described nor does it cover any license under its patent rights or the rights of others. The apparatus and application of the apparatus described in this document is protected by US Patent Number 6,949,741 and used under license; additional patents pending. All trademarks are properties of their respective owners. 2
This manual details the steps necessary to install a DART source on a Thermo LTQ Ion Trap or Orbitrap Instrument. Table of Contents 1. Diagram of the Thermo Source Region 2. Attaching the DART Flange to the Instrument a. Adjusting the Exactive Side Brackets 3. Vacuum Issues 4. Optimal Parameters 3
Diagram of the Thermo Source Region and Interface Disconnect the waste hose from the bottom of the Ion Max source, as well as all gas, syringe, and voltage connections. Carefully remove the Ion Max source from the Mass Spectrometer interface and place it aside in a safe place. Remove the Thermo ion sweep cone as shown in the photo above this is the removable spray shield that sits over the capillary. Using a small flat-head screw driver, loosen the set screws on the sides of the spray shield. Caution: the shield may be hot. Pictured to the left is the source region with the Thermo ion sweep cone removed. 4
Adjusting the Side Brackets on the Thermo Exactive Instrument The side brackets (circled in red in the picture below) need to be adjusted before mounting the IonSense SI-140-GIST Vapur interface flange to an Exactive. The side brackets on the Exactive and LTQ need to be set 0.2-0.3 mm out from the front metal surface around the API inlet. In general these brackets are set flush with the metal surface around the API inlet as a default position. The Thermo ESI source will fit properly even with the changed positioning of the side brackets. The side brackets on the Exactive and LTQ need to be adjusted so that the front surface of the brackets measures 0.2 0.3 mm from the front metal surface around the API inlet. The brackets are to be moved away from the mass spectrometer and towards the installation engineer. Note: The Thermo spray shield is also removed before mounting the IonSense Vapur interface flange. 5
Attaching the DART Flange to the Instrument Attach the IonSense flange to the source by matching the lock bars with the slots on the side and then locking them on the top by turning the knobs simultaneously until they are facing at least 45 degrees from the side plane of the flange. Insert the ceramic tube into the Swagelok nut on the end of the VAPUR attachment and secure it with the graphite ferrule. Take care that there is a 2mm gap inside the VAPUR between the end of the ceramic tube and the protruding end of the Agilent capillary. This ensures that the excess helium gas will be evacuated and maintain proper vacuum in the instrument. Then, attach the DART either by 1) attaching the large front ring of the DART to the holes on the front of the flange, or 2) by screwing the base of the DART into the two holes on the bottom of the flange. Attach the black silicone rubber tubing to the port on the left side of the flange. Finally, attach the DART source to the flange. Figure: The DART is shown attached to the flange using the screws in the front ring. 6
Monitoring Vacuum Levels Use of the DART will increase the vacuum level in your instrument due to the amount of helium being pushed into the instrument. It will not, however, harm the mass spectrometer or cause it to function differently. Below is a printout showing what the Thermo Exactive s vacuum levels should be during operation. If your vacuum levels exceed this amount, call IonSense and ask to speak with the Service Department. Stable vacuum pressure read back values for the Exactive. N 2 is running through the DART source for this screen shot. UHV reading will rise to ~ 8-9 E-10 mbar when operating the DART with He, but is still stable. The threshold where the UHV will fail is at 1.26 E-9 mbar. 7
Optimal Parameters IonSense recommends using the following operational settings: Scan Parameters: Scan Settings: 1 µ-scan by 250 ms max inject time AGC Target: Balanced (1e 6 ) Inlet Parameters: Capillary Temp: 200 C 200 C Capillary Voltage: 25 V - 50 V Tube Lens Voltage: 120 V -120 V Skimmer Voltage: 26 V -25 V The following Source Parameters are set to zero: Sheath Gas Flow, Aux Gas Flow, Sweep Gas Flow. For all ID-CUBE experiments the Spray Voltage was set to 1 kv. 8