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Cited by 1Forensic Toxicology and Drug AnalysisBiosensors and Analytical DetectionOpioid Use Disorder Treatment

Decoding the Unseen: A Systematic Review of the Analytical Performance of Nitazene Test Strips for Identifying Synthetic Opioids in Seized Drug Materials

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Al-Juhani, Abdulkreem, Alasmari, Abdulelah, Aljohani, Omar O, Hakeem, Hatoon, Desoky, Rodan, Badghaish, Muhannad A, Aljohani, Naif, Alanazi, Fai A·2025·Cureus
DOI 10.7759/cureus.99109PMC PMC12794522
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Abstract

Nitazenes are highly potent synthetic opioids increasingly detected in illicit drug markets and associated with significant public-health and forensic challenges. Rapid identification tools, such as lateral-flow immunoassay (LFA) test strips, are widely used in harm-reduction and forensic settings; however, their analytical performance for detecting nitazene-class opioids remains insufficiently characterized. This systematic review aims to evaluate the analytical performance of nitazene LFA test strips when used on seized drug materials and laboratory-prepared solutions, compared with mass spectrometry (MS) reference methods (liquid chromatography-tandem mass spectrometry (LC-MS/MS), liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS), and gas chromatography-mass spectrometry (GC-MS)). Outcomes included sensitivity, specificity, cross-reactivity, limits of detection, and operational interferences. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Diagnostic-Test Accuracy (PRISMA-DTA) guidelines and applying Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) framework, five eligible studies were synthesized, including laboratory evaluations and field-paired analyses. Only studies evaluating LFAs on drug materials - not biological samples - were included. Our results showed that two studies provided paired LFA-mass-spectrometry datasets. Under concentrated preparation conditions (10 mg/1 mL), LFAs demonstrated complete agreement with MS. Sensitivity declined at higher dilution (10 mg/5 mL), while specificity remained high. Analytical detectability varied substantially across nitazene analogues, with N-desethyl-metonitazene exhibiting the greatest sensitivity. Matrix effects, caffeine adulteration (~300 µg/mL), solvent concentrations >10% acetonitrile, and elevated temperatures all reduced line intensity or hindered wicking. In conclusion, Nitazene LFA test strips show potential value as preliminary material-based screening tools in forensic and harm-reduction applications, but should not be interpreted as confirmatory. Their use requires standardized protocols, conservative interpretation rules, and mandatory mass-spectrometric confirmation. Large, independent, multi-site analytical validation studies are needed to establish reliability, optimize field use, and support integration into drug-checking programs.

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  • Nitazene immunoassay test strips detected 28 of 36 nitazene compounds, showing partial effectiveness as rapid screening tools.

    “Recent work on nitazene immunoassays test strips show partial effectiveness as a rapid screening tools, with these strips detecting 28 of 36 nitazene compounds [43].”

    From Novel 2-Benzylbenzimidazole Opioids: Emerging Drugs of Abuse and Pharmacological Considerations with Nitazene Analogs (2026) · cites this paper as [43]

    The Review’s analogue-level detection section reports that 24 of 33 nitazene analogues were identified at concentrations below 9000 ng/mL, not that 28 of 36 were detected. The Conclusions support the broader point that the strips may serve as preliminary screening tools, subject to confirmatory testing. The claimed detection count is unsupported by our copy. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Nitazene immunoassay test strip performance limitations include false negatives and false positives linked to high caffeine concentrations.

    “However, performance limitations are observed, with false negatives, and false positives, both being linked to high caffeine concentrations [43].”

    From Novel 2-Benzylbenzimidazole Opioids: Emerging Drugs of Abuse and Pharmacological Considerations with Nitazene Analogs (2026) · cites this paper as [43]

    The Review’s “Interferences, Matrix Effects, and Operational Findings” section and Table 4 link caffeine at about 300 µg/mL to a false-negative risk. The paper discusses false positives generally, but the cited passages do not link them to high caffeine concentrations; the paired accuracy data report no false positives. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

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Authors
Al-Juhani, A., Alasmari, A., Aljohani, O. O., Hakeem, H., Desoky, R., Badghaish, M. A., Aljohani, N., & Alanazi, F. A.
Affiliations
  • King Abdulaziz University (SA)
  • Ministry of Health (SA)
  • Prince Mohammed bin Abdulaziz Hospital (SA)
  • Alfaisal University (SA)
  • Naif Arab University for Security Sciences (SA)
Corresponding author
Al-Juhani, Abdulkreem
Venue
Cureus
Publisher
Springer Science and Business Media LLC
Published
2025-12-13
Volume
17
Issue
12
Pages
e99109-e99109
ISSN
2168-8184 (ISSN-L)
DOI
10.7759/cureus.99109
PMC
PMC12794522
OpenAlex
W7114996372
Cited by
1
References
7
Citations by year
2026: 1
FWCI
0.18
Type
journal article
Language
en
Open access
Licence
cc-by
Locations
  • Cureus (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • PubMed Central (publishedVersion, cc-by)
Topics
  • Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Toxicology › Forensic Toxicology and Drug Analysis
  • Physical Sciences › Engineering › Biomedical Engineering › Biosensors and Analytical Detection
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Opioid Use Disorder Treatment
Keywords
nitazenes, synthetic opioids, lateral flow immunoassay, drug checking, diagnostic accuracy, sensitivity and specificity, matrix effects, harm reduction, forensic drug analysis

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