"Frugal Forensics":
Plant-Based Color Sensors
for the Field
How naturally occurring plant pigments could transform forensic chemistry — making drug and explosive detection rapid, low-cost, and globally accessible.
What Is "Frugal Forensics" — and Why Does It Matter?
Imagine a forensic investigator working far from a city — no specialist lab, no gas chromatography machine, no mass spectrometer. Yet she needs to rapidly confirm whether a suspicious white powder is a controlled drug, whether a residue contains explosive precursors, or whether a liquid is a chemical warfare agent. Today, this scenario is a daily reality for law enforcement officers, border agents, and first responders across large parts of Africa, Asia, and Latin America.
Enter "frugal forensics" — a growing scientific movement dedicated to building forensic tools that are fast, reliable, and inexpensive enough to work outside the laboratory. At the leading edge of this field is Dr. Raychelle Burks, an Associate Professor of Chemistry and Provost at American University in Washington D.C., who is now bringing her groundbreaking work to Curtin University in Perth, Australia as a Fulbright US Scholar for 2026–27.
"Anthocyanins are globally abundant and highly responsive compounds, making them promising candidates for simple, low-cost chemical detection."
— Dr. Raychelle Burks, American University / Curtin University, April 2026Meet Dr. Raychelle Burks: The Scientist Behind the Research
Dr. Burks is no newcomer to forensic chemistry. Her academic journey traces from a Bachelor of Science in Chemistry at the University of Northern Iowa, a Master of Forensic Science from Nebraska Wesleyan University, to a PhD in Chemistry from the University of Nebraska–Lincoln, followed by postdoctoral research at Doane College.
Crucially, she also spent time working in an actual crime laboratory before returning to academia — and that hands-on experience shaped everything. It instilled in her the mission to create forensic tools that are field-ready, robust, and low-cost. Since establishing her research team (the Burks Research Team, BRT) in 2016, she has focused on the development of colorimetric and luminescent chemosensor arrays for substances of forensic and national security interest.
The American Chemical Society recognised her impact with the prestigious 2020 Grady-Stack Award for excellence in public engagement. She is also a science communicator who has appeared on the Science Channel, Smithsonian Channel, NPR, and at conventions like DragonCon and GeekGirlCon. Her forensic science column Trace Analysis runs in Chemistry World.
Academic Role
Associate Professor of Analytical Chemistry & Provost, American University, Washington D.C.
Research Focus
Low-cost colorimetric & luminescent sensors for forensic and national security analytes.
Innovation
Transforming smartphones into field-deployable chemical detection devices.
Recognition
ACS Grady-Stack Award 2020; Fulbright US Scholar 2026–27; NSF C-CAS affiliate ($20M Phase II).
The Science: What Are Anthocyanins?
Anthocyanins are water-soluble natural pigments belonging to the flavonoid family. They are responsible for the vivid red, purple, and blue colours found in blueberries, red cabbage, grapes, purple carrots, eggplant, hibiscus flowers, and hundreds of other plants. Crucially for forensic science, anthocyanins are chemically reactive to changes in their environment — especially to pH shifts and the presence of metal ions or other reactive compounds.
Under acidic conditions, anthocyanins appear red. Under neutral conditions they turn blue or purple. Under alkaline conditions they shift to green or yellow. This visible colour-change behaviour means they can essentially act as naked-eye sensors — you can see the reaction without any instrument at all.
Why is this exciting for forensics? Many drugs, explosive precursors, and toxic chemicals are either acidic, alkaline, or chemically reactive. Anthocyanin-based sensors can be tuned to produce distinctive colour signatures in response to specific target compounds — making detection possible without a laboratory.
How Anthocyanin Sensors Work: Step by Step
Extraction: Anthocyanin pigments are extracted from readily available plant sources (red cabbage, purple onion, berries) — sources that are cheap and globally accessible.
Substrate Loading: The anthocyanin is embedded into a solid-state substrate, such as bacterial cellulose nanofibers, paper, or polymer nanofibers, creating a stable sensor strip or patch.
Field Application: A small sample of the suspect substance is brought into contact with the sensor (by swabbing, dipping, or vapour exposure).
Colour Change: The anthocyanin reacts chemically, producing a distinctive, visible colour change — or a change in fluorescence — unique to the target compound.
Digital Capture & Analysis: The colour result can be photographed using a smartphone and analysed using image-processing apps or chemometric software, turning a mobile phone into a portable spectrometer.
Result Interpretation: Results can be cross-referenced against a standardised colour reference chart, enabling even non-specialist personnel to make an initial identification in the field.
The Curtin University Collaboration: A Global Partnership
Dr. Burks' Fulbright award brings her to Curtin University's Forensic and Analytical Chemistry Research Group within the School of Molecular and Life Sciences for 2026–27. She will work closely with:
- Professor Simon Lewis — an authority on forensic chemistry, trace evidence, and analytical methods
- Dr. Georgina Sauzier — researcher in forensic and analytical chemistry
Together, the team aims to develop and validate anthocyanin-based sensors capable of detecting a triad of high-priority threat substances: illicit drugs, explosives, and chemical warfare agents. The research will also explore how smartphone-based image analysis can extend these sensors' utility to extremely remote environments.
Curtin University Vice-Chancellor Professor Harlene Hayne stated that the collaboration "reflects Curtin's commitment to impactful, internationally connected research that addresses real-world challenges." Professor Lewis described the partnership as "an exciting opportunity to advance new approaches that could make forensic science more equitable and widely available."
Traditional Lab Testing vs. Frugal Forensic Sensors: A Comparison
| Parameter | Traditional Lab Methods (GC-MS, HPLC etc.) |
Anthocyanin Frugal Sensors |
|---|---|---|
| Cost | Very high (equipment: $50,000–$500,000+) | Very low (plant extract + paper/nanofiber strip) |
| Time to Result | Hours to days (sample transport + processing) | Seconds to minutes on-site |
| Portability | Lab-bound; heavy instruments | Fully portable; fits in a pocket |
| Specialist Training | Requires highly trained technicians | Minimal training required; visual readout |
| Environmental Impact | Uses toxic solvents; generates hazardous waste | Green chemistry; minimal waste; biodegradable |
| Accessibility (Global) | Available mainly in developed nations | Viable for developing nations and remote areas |
| Targets Detected | Very high specificity for confirmed compounds | Broad screening (drugs, explosives, toxins, metals) |
| Data Processing | Dedicated software, lab computers | Smartphone image analysis apps |
| Result Type | Quantitative (precise concentrations) | Qualitative / semi-quantitative (rapid screening) |
What Can These Sensors Detect? The Threat Landscape
The substances of interest in this research fall into three broad categories of international concern:
1. Illicit Drugs
According to the UN Office on Drugs and Crime (UNODC), nearly 292 million people globally were exposed to drugs in 2022, with over 64 million suffering from drug use disorders. Methamphetamine, cocaine, heroin, fentanyl, and novel synthetic drugs (NPS) are priority targets. Current field tests (e.g., Marquis, Scott's reagent) are single-compound spot tests that give limited information. Anthocyanin-based sensor arrays can generate multi-point colour signatures, providing a richer fingerprint of an unknown substance.
2. Explosives
Explosives — including metal acetylides, organic peroxides, nitrated aromatic compounds, and fuel-oxidiser mixtures — are reactive species whose decomposition products are often more detectable than the parent compound. Colorimetric sensor arrays have already been validated for explosive detection, including research co-authored by Dr. Burks herself, published in Critical Reviews in Analytical Chemistry.
3. Chemical Warfare Agents (CWAs)
Nerve agents such as sarin, soman, and tabun, vesicants like mustard gas and lewisite, and blood agents like hydrogen cyanide pose the most acute threat scenarios. Their colourless, odourless nature makes rapid field detection critically important. Developing low-cost sensors for CWAs is particularly vital for humanitarian responders in conflict zones where laboratory infrastructure is absent.
Anthocyanin Sensor Research: Selected Global Studies
| Study / Source | Plant Source Used | Target Detected | Key Finding |
|---|---|---|---|
| Arghavani et al., 2023 (PMC) |
Purple onion peels (bacterial cellulose nanofibers) | Aluminium (Al³⁺) ions | Naked-eye detection; response time in seconds; detection limit 20–300 ppm (solid state) |
| Mohseni-Shahri et al., 2023 (PMC) |
Jambolao fruit (Syzygium cumini) | Copper (Cu²⁺) ions | Selective sensor, 10–400 ppm (liquid), excellent selectivity over 10 other metal ions |
| Burks et al. — DETECHIP, 2010 (J. Forensic Sci.) |
N/A (colorimetric dye array) | Drugs of abuse | 20-response array; quantitative colour + fluorescence codes for multiple drugs |
| ScienceDirect Review, 2024 | Various (berries, red cabbage, etc.) | pH, food quality, environmental monitoring | Anthocyanins viable as green reagents for solid-state colorimetric sensors across multiple fields |
| PMC Nanofiber Study, 2025 | Hibiscus sabdariffa (Roselle) | pH detection (chemical spills, ocular pH) | Response in under 5 seconds; colour shift from pink → blue → green across pH 1–12 |
| Burks / Curtin (ongoing, 2026–27) | Globally abundant plants (TBC) | Illicit drugs, explosives, CWAs | Field-deployable, smartphone-readable colour sensors for substances of international concern |
Why This Research is a Game-Changer for Developing Nations
The global forensic technology market was valued at USD 5.96 billion in 2024 and is dominated by North America, which holds over 38% market share. High-income countries operate thousands of fully equipped forensic laboratories. The reality for much of the developing world, however, is starkly different: limited infrastructure, shortage of trained personnel, unreliable power supply, and extreme cost constraints.
Field officers in such regions often rely on colour-change reagent kits (such as the Scott Test for cocaine, or the Duquenois-Levine test for cannabis) — methods that are decades old, limited to a single drug class, and prone to false positives. The advent of anthocyanin-based multi-sensor arrays could represent a quantum leap for these frontline investigators.
Global Equity
Makes modern forensic screening accessible to all nations, not just those with well-funded laboratories.
Rapid Response
Seconds-to-minutes results in the field versus days for lab processing — critical in emergencies.
Smartphone Integration
Turns a basic mobile phone into a detection device — no specialist equipment required.
Green Chemistry
Natural, biodegradable reagents — aligns with sustainable and environmentally responsible science.
Forensic Technique Spotlight: Forensic Chemistry & Toxicology
Forensic Chemistry is the application of chemistry to legal investigations — identifying unknown substances found at crime scenes or on individuals. Forensic Toxicology specifically involves detecting drugs, poisons, and other toxic substances in biological and environmental samples.
The anthocyanin sensor work sits squarely at the intersection of both fields. It uses chemical reactions (forensic chemistry) to screen for substances that include poisons and narcotics (forensic toxicology), doing so in real-time field conditions rather than in post-mortem laboratory analysis alone.
Traditional forensic chemistry uses techniques such as Gas Chromatography-Mass Spectrometry (GC-MS), High Performance Liquid Chromatography (HPLC), Raman spectroscopy, and Fourier-Transform Infrared Spectroscopy (FTIR). These remain the gold standard for confirmation of identity in court. The role of frugal sensors is as a rapid presumptive screening tool — providing fast, actionable information in the field to guide further investigation, not replacing laboratory confirmation entirely.
"This partnership brings together complementary strengths to tackle complex detection challenges in a practical and scalable way. It's an exciting opportunity to advance new approaches that could make forensic science more equitable and widely available."
— Professor Simon Lewis, Curtin University Forensic and Analytical Chemistry Research GroupWhat Comes Next: The Road Ahead for Plant-Based Forensic Sensors
The Burks–Curtin collaboration is expected to run through 2026–27. Key goals include validating anthocyanin-based sensors for specific drug and explosive compounds, developing standardised colour reference charts for field use, and integrating smartphone-based image capture with chemometric analysis software.
In the broader landscape, researchers are increasingly combining anthocyanin sensors with machine learning models, as demonstrated in recent studies where ML algorithms analysed colorimetric results from controlled sensor experiments to detect explosives and narcotics. This AI-assisted interpretation layer could dramatically improve both sensitivity and specificity — moving frugal forensics even closer to lab-quality results.
Given that demand for mobile and field-deployable forensic kits is rising fastest in developing regions, and that the overall forensic technology market is projected to grow to USD 68+ billion by 2035, the commercial and humanitarian case for affordable plant-based sensors is only growing stronger.
Key Takeaways for Budding Forensic Experts
1. Nature can be a lab. Compounds from everyday plants — the pigments in your blueberries — can be harnessed as sophisticated chemical sensors.
2. Access matters. The best forensic tool is one that actually exists where it's needed. Frugal forensics democratises a field that has long been dominated by wealthy nations.
3. Smartphones are instruments. Pairing visual sensors with mobile phone cameras and analysis software is a powerful paradigm shift in portable analytical chemistry.
4. Screening ≠ Confirmation. Rapid colorimetric sensors are presumptive screening tools. Confirmatory lab analysis (GC-MS etc.) remains essential for legal proceedings.
5. Green forensics is the future. Sustainable, biodegradable reagents align forensic science with broader environmental responsibility goals.
📚 Sources & Further Reading
- Curtin University Media Release (30 April 2026) — Fulbright scholar taps plant-based science for next-generation forensic tools
https://www.curtin.edu.au/news/media-release/fulbright-scholar-taps-plant-based-science-for-next-generation-forensic-tools/ - Forensic Magazine (May 2026) — Forensic Chemist Exploring Plant-based Science for 'Frugal Forensics'
https://www.forensicmag.com/3594-All-News/625503-Forensic-Chemist-Exploring-Plant-based-Science-for-Frugal-Forensics/ - Mirage News (April 2026) — Fulbright Scholar Innovates Forensic Tools with Plants
https://www.miragenews.com/fulbright-scholar-innovates-forensic-tools-with-1664812/ - Wikipedia — Raychelle Burks
https://en.wikipedia.org/wiki/Raychelle_Burks - American University Faculty Profile — Dr. Raychelle Burks
https://www.american.edu/cas/faculty/burks.cfm - American Chemical Society — Dr. Raychelle Burks Profile
https://acs.digitellinc.com/b/sp/raychelle-burks-207030 - NSF Center for Computer Assisted Synthesis — Raychelle Burks
https://ccas.nd.edu/people/raychelle-burks/ - PMC / NCBI — Green metallochromic indicator for copper(II) ions (anthocyanin from Syzygium cumini)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10397238/ - PMC / NCBI — Anthocyanin-loaded bacterial cellulose nanofiber: Al(III) ion detection (2023)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10989543/ - ScienceDirect (2024) — Review: Anthocyanins as natural reagents for eco-friendly solid-state colorimetric sensors
https://www.sciencedirect.com/science/article/pii/S2772577424000260 - Frontiers in Chemistry (2025) — A systematic review of sensors to combat crime
https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2025.1568867/pdf - Tandfonline — Colorimetric Sensor Arrays for Detection of Chemical Weapons and Explosives (Burks et al.)
https://www.tandfonline.com/doi/full/10.1080/10408347.2016.1233805 - MDPI Applied Sciences (Jan 2026) — Nanomaterial-Based and Colorimetric Technologies for Illicit Drug & Environmental Toxin Detection
https://www.mdpi.com/2076-3417/16/2/693 - Market Business Insights — Forensic Technologies Market Forecast 2035
https://www.marketbusinessinsights.com/forensic-technologies-market
