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Replace the septa of the «Flushing» position after each batch of samples.
Soak the needle in some milli-Q water after each use in order to prevent build-up of acid and debris from septa at the needle.
Clean potential acid drops on every septa after acid addition (before sampling).
Do not reuse septas.
Clean as well the Liquid Syringe with water to remove acid remnants.
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