How to Clean the ICP-MS Torch

Answer

This Information Applies To: Agilent ICP-MS systems (7700/7800/7850/7900/8800/8900)

Issue

How to perform routine maintenance on the Agilent ICP-MS Torch.

Background

Deposits on the torch can be removed by routine maintenance. Maintenance frequency depends on sample throughput and sample type. Inspect the torch regularly, and if deposits are visible, clean the torch.

Items Required

• Safety glasses
• Protective laboratory gloves
• 5% nitric acid bath (or optional 50% aqua regia)
• Pure de-ionized water in a rinse container

Steps to Follow

1. Remove the ICP-MS torch
2. Soak the torch in 5% nitric acid (Figure 1). Tilt the torch when immersing to remove any bubbles that may be trapped inside the torch.
   

    

   Caution: Do not place the torch in an ultrasonic bath. An ultrasonic bath may break the torch.

   
   

   
   
   Figure 1. Torch immersed in 5% nitric acid bath
   
   

3. Soak until the deposits are removed (typically 30 minutes to a few hours). It is not harmful to leave soaking overnight if needed. For stubborn deposits, soak in 50% aqua regia.
   

    

   Caution: Appropriate PPE must be used when handling nitric acid and especially 50% aqua regia. See the MSDS suppled with these chemicals for guidance on the PPE required for safe handling and use of these chemicals

   
   
   
4. Rinse the torch thoroughly with pure de-ionized water (Figure 2).
   

    

   Tips: Pure water used for cleaning is indicated as water that has been generated using the ion-exchange method and a membrane filter, and has an electrical resistance of at least 18MΩ cm.

   
   
   Figure 2. Rinsing torch with de-ionized water
   
   

5. Dry the torch with clean air, nitrogen, or argon gas. Alternately, place the torch in a drying oven overnight (Figure 3).
   

   
   
   Figure 3. Drying torch with clean air, nitrogen, or argon gas
   
   

   Caution: Thoroughly dry the torch before continuing. A wet torch will not light and may damage the torch irreversibly during the plasma ignition attempt.

    

6. Install the ICP-MS torch.

Learn how to effectively maintain your Agilent ICP-MS System:  Agilent 7800/7850/7900 ICP-MS with MassHunter Agilent 8900 Triple Quadrupole ICP-MS with MassHunter eLearning courses available from Agilent