{"id":51709,"date":"2014-12-10T14:30:00","date_gmt":"2014-12-10T14:30:00","guid":{"rendered":"https:\/\/discover.restek.com\/uncategorized\/how-dirty-are-you-part-4manual-syringe-rinsingthe-answer\/"},"modified":"2026-01-28T15:54:10","modified_gmt":"2026-01-28T15:54:10","slug":"how-dirty-are-you-part-4manual-syringe-rinsingthe-answer","status":"publish","type":"post","link":"https:\/\/discover.restek.com\/fr\/blogs\/gnbl4696\/how-dirty-are-you-part-4manual-syringe-rinsingthe-answer","title":{"rendered":"How Dirty Are You? Part 4\u2026Manual Syringe Rinsing\u2026The Answer"},"content":{"rendered":"\n

So how many times do you need to rinse a syringe?<\/p>\n\n\n\n

Well, I can tell you the answer for the experiment we did<\/a>. Let me first refresh your memory on specifically what we did.<\/p>\n\n\n\n

Sequence of manual syringe rinsing:<\/h3>\n\n\n\n
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  1. 20 \u00b5L draw of a 500 ppm hydrocarbon standard and expel it<\/li>\n\n\n\n
  2. 20 \u00b5L draw of acetonitrile \u2013 eject into sample vial \u2013 test via GC-FID<\/li>\n\n\n\n
  3. Repeat step 2 many times<\/li>\n<\/ol>\n\n\n\n

    Each “rinse” was tested via GC-FID.<\/p>\n\n\n\n

    How many 20 \u00b5L acetonitrile rinses were needed to show no signal (FID)?<\/h2>\n\n\n\n

    The answer is 4.<\/h3>\n\n\n\n

    I want to thank everyone that commented when I posed the question<\/a>. Most people were right on track with about 4 rinses. It is also funny that people tended to do \u201cextra\u201d rinsing regardless of what they thought was required. I still do this with about 6 to 10 rinses depending on the situation.<\/p>\n\n\n\n

    I wanted to share some helpful hints from people who commented:<\/p>\n\n\n\n