A paper-based sensor using the modified Van Urk reaction accurately quantifies melatonin in pharmaceutical formulations
The study developed a paper-based microfluidic sensor for melatonin quantification in pharmaceutical formulations, using the modified Van Urk reaction that produces a blue color proportional to melatonin concentration. The sensor showed good linearity (R2 = 0.9915) over a range of 40-300 mg/L and performed well in quantifying melatonin in solid (0.22 mg/tablet) and liquid (0.20 mg/drop) formulations, with results comparable to liquid chromatography.
This article is automatically generated from the structured evidence profile behind the claim above. Scores reflect the quality and quantity of available research, not clinical advice.
A paper-based sensor using the modified Van Urk reaction accurately quantifies melatonin in pharmaceutical formulations The current body of evidence comprises 1 study. EvidenceHub rates the overall confidence at 32/100 (low).
The Claim
A paper-based sensor using the modified Van Urk reaction accurately quantifies melatonin in pharmaceutical formulations
This conclusion is most relevant to: Pharmaceutical formulations (solid tablets and liquid drops) containing melatonin.
What the Research Shows
The conclusion draws on 1 linked study. Highlights from the cited literature:
- ▸μPADs for a Safer Night's Sleep: An Alternative for Quality Control of Melatonin Pharmaceutical Formulations. (ACS omega, 2026) —
How It Works
The proposed biological pathway:
- ▸Sample containing melatonin is applied to the paper sensor
- ▸Modified Van Urk reaction occurs on the paper surface
- ▸Color changes from white to blue, intensity proportional to melatonin concentration
- ▸Color intensity is correlated with melatonin concentration for quantification
Who Might Benefit
Evidence fit by population:
- ▸Pharmaceutical formulations (solid tablets and liquid drops) containing melatonin
Recommended Dose
N/A
Limitations & Caveats
Important context when interpreting this evidence:
- ▸The study is a proof-of-concept; no validation on real patient samples or clinical settings
- ▸The sensor's performance was only tested on a limited number of formulations, and the effect of potential interfering substances (e.g., other hormones) was not fully explored
Frequently Asked Questions
What is the modified Van Urk reaction?▼
It is a chemical reaction that produces a color change (from white to blue) when melatonin is present, allowing for colorimetric detection and quantification.
What is the detection range of the paper-based sensor?▼
The sensor demonstrated good linearity over a melatonin concentration range of 40-300 mg/L.
How does the sensor compare to standard methods like liquid chromatography?▼
The sensor's results were comparable to those obtained by liquid chromatography, with a maximum standard deviation within acceptable limits, suggesting it could be a low-cost alternative for quality control.
What are the potential applications of this sensor?▼
It can be used for quality control of melatonin pharmaceutical formulations, ensuring accurate dosage and detecting potential contamination, which is important for safety.
References
- 1.Ramos AJA, Brazaca LC, Rossini EL, Lima MJA, Carrilho E. “μPADs for a Safer Night's Sleep: An Alternative for Quality Control of Melatonin Pharmaceutical Formulations..” ACS omega, 2026. PMID: 42662326 DOI: 10.1021/acsomega.6c03837