NIK Polytesting
Definition
A field drug testing approach using the NIK Public Safety sealed ampoule system, where multiple colour tests are run sequentially on the same exhibit so that no single test result is used in isolation. The combined pattern from two or more tests improves selectivity over any individual reagent.
- System
- NIK Public Safety sealed ampoule kits
- Method
- Multiple colour tests run sequentially on same exhibit
- Purpose
- Combined pattern improves selectivity over a single test
Common questions
Why is a single colour test result treated as insufficient on its own?+
Individual presumptive colour tests are prone to false positives from common household and pharmaceutical substances, so a single positive reaction is only an investigative screen, not a specific identification, and must be followed by confirmatory laboratory analysis.
How does running multiple NIK tests sequentially improve field screening?+
Each reagent responds to a different chemical class, so a substance that produces the expected colour pattern across several sequential tests is far less likely to be a coincidental false positive than one flagged by a single reagent alone.
Does a positive NIK polytesting result replace laboratory confirmation?+
No. Field colour tests, however many are combined, remain presumptive and are not a substitute for confirmatory instrumental analysis such as GC-MS in a controlled laboratory before evidentiary identification is reported.
Related terms
- Cobalt Thiocyanate
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- Duquenois-Levine Test
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- False Positive (Presumptive Test)
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- Mandelin Reagent
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- Marquis Reagent
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- Mecke Reagent
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- Scott Test
- A three-step cobalt thiocyanate presumptive test for cocaine and its salts. Step 1: cobalt thiocyanate reagent (blue in aqueous phase). Step 2:...
- Simon's Test
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- SWGDRUG Category C
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