Judging the purity of illegal drugs usually requires professional laboratory analysis, but there are indeed some rapid testing tools that can be used to initially screen for drug ingredients or certain adulterants. The following is a summary of relevant information： ### 1. **Common rapid test strips/reagents** -**Immunochromatographic test strips**: For example, drug test strips (for cocaine, heroin, methamphetamine, etc.) can qualitatively detect whether they contain specific ingredients, but the purity cannot be directly determined. -**Chemical kit** (such as Ma Chang Reagent, Mandelin reagent): Determine the type of drug by color change, such as： - **Horse modification reagent (Marquis)**: Detection of MDMA, heroin, etc. - **Cobalt thiocyanate test strip**: Preliminary judgment of MDMA concentration (semi-quantitative, but with large error). -**Fentanyl test strips**: Used to detect whether a drug is mixed with fentanyl (a powerful opiate). ### 2. **Limitations** -**Qualitative rather than quantitative**: Most test strips can only confirm the presence of ingredients, and the purity cannot be accurately calculated. -**Cross-reaction**: May produce false positives for similar structural substances. - **All dopants cannot be detected**: Illegal drugs are often mixed with unknown ingredients (such as caffeine, talcum powder, and other synthetic drugs), and a single test strip cannot fully cover them. ### 3. **Alternative to purity assessment** -**Portable spectrometer** (such as Raman spectrometer): Used by some law enforcement agencies, it can quickly identify the main components and proportions, but laboratory verification is still required. -**Laboratory analysis**: Gas chromatography-mass spectrometry (GC-MS) is the gold standard and can accurately determine purity, but professional equipment and time are required. ### 4. **Safety and legal tips** -Self-testing for illegal drugs is a legal risk and may endanger health (such as exposure to highly toxic substances). -If adulteration of drugs is suspected, avoid use and contact a professional organization. ### Summary Rapid detection test strips can assist in the identification of specific ingredients or high-risk dopants (such as fentanyl), but purity cannot be accurately determined. Purity assessment still relies on laboratory technology. The issue of illegal drugs must be treated with caution, and safety and legal consequences must be given priority.