Fluoro‑Spec™ Lead Detection Kit

A Fluorescence Spectroscopy Based Method for Lead Disclosure

Executive Summary

Fluoro‑Spec™ is a field‑deployable lead screening system that uses in‑situ formation of photoluminescent lead halide perovskites to indicate the presence of lead on environmental surfaces. When the Methylammonium Bromide containing reagent is put i contact with a lead‑containing surface and illuminated with ultraviolet (UV) light, a bright green fluorescence is produced that is readily observable by eye.

Unlike electronic analytical methods, Fluoro‑Spec™ is designed for rapid, low‑cost, on‑site screening of painted surfaces, dust, metals, glass, and other real‑world substrates where lead may be present as oxides, carbonates, or mixed phases chemically reacted with components of rubber, plastic or bound . The system is intended as a screening and risk‑identification tool, enabling users to quickly identify locations that warrant concern.

Background and Rationale

Origin and Scientific Context

The development of Fluoro-Spec™ was informed by direct engagement with the academic research community studying environmental lead exposure and detection. In November 2022, Fluoro-Spec’s founder learned of emerging fluorescence-based lead detection approaches through discussions with Professor Alexander van Geen (Columbia University), who highlighted recent research demonstrating the use of lead halide perovskite photoluminescence as an extremely sensitive indicator of lead.

That conversation helped connect foundational materials-science research with a clear unmet need in environmental health: a practical, low-cost, field-deployable screening method for lead on real-world surfaces. Fluoro-Spec™ was subsequently developed to address apparent deficits in the marketplace for such testing kits.

The result was a more sensitive, shelf stable, iteration of what had come before, which provided substantially more testing fluid and a stronger UV excitation source.

Fluorescent Perovskite Formation as a Detection Mechanism

The photoluminescent behavior leveraged by Fluoro-Spec™ is grounded in prior academic research and publicly released product formulations demonstrating that lead-containing solids can be converted in situ into highly emissive lead halide perovskites upon contact with methylammonium halide reagents and UV excitation.

Early foundational work by Holtus et al. (2018) demonstrated that solid lead carbonate (PbCO₃) could be rapidly transformed into methylammonium lead halide perovskites by application of methylammonium bromide solution, with bright green photoluminescence observed under UV illumination.

Although that work was directed toward semiconductor materials synthesis, it established the underlying surface reaction and optical response that Fluoro-Spec™ relies on for environmental lead screening.

Subsequent sensing-focused research by Wang et al. (2021) explicitly demonstrated that lead on a solid substrate could be detected via fluorescence turn-on resulting from in-situ MAPbBr₃ perovskite growth. That work framed perovskite photoluminescence as a diagnostic signal for lead presence, in fact detection of lead in this case was shown to be thousands of times more sensitive than traditional lead detection chemical tests.

Fluoro-Spec™ leverages these scientific foundations by translating the same photoluminescent chemistry.

Lead halide perovskites are well known for their intense photoluminescence under UV excitation. When lead‑containing surface phases come into contact with an appropriate halide reagent system, localized perovskite crystals form in situ, producing a visible fluorescence signal.

Scientific Principle of Operation

Reagent Composition

Fluoro-Spec™ uses a proprietary reagent blend based on methylammonium bromide (MABr) combined with mandelic acid in a stabilized formulation. The reagent is supplied at an effective working potency optimized for rapid surface reaction, strong fluorescence yield, and long shelf life.

The formulation is designed to:

• promote rapid in-situ formation of photoluminescent lead halide perovskites,
• improve wetting and surface contact on painted, metallic, plastic, and glass substrates,
• enhance signal consistency under field conditions.
• Prevent the mobility of microscopic lead crystals.

Scientific Principle of Operation

Lead Speciation on Real‑World Surfaces

In environmental contexts, lead is typically present in bound solid phases, including:

• carbonates and basic carbonates (e.g., hydrocerussite) in lead‑based paint,
• oxides and hydroxides on metal surfaces,
• mixed mineral phases in dust and debris,
• complexed or adsorbed forms on plastics or glass surfaces.

Importantly, these forms are surface‑accessible, even though chemically bound, and can participate in solid–liquid reactions.

Optical Detection

Fluoro‑Spec™ uses UV excitation at wavelengths shorter than the emission band of the perovskite. Emitted light is detected:

• visually by the user, and/or
• with a simple UV flashlight

No complex instrumentation is required.

System Design and Components

A standard Fluoro-Spec™ kit includes:

• Fluoro-Spec™ reagent: proprietary methylammonium bromide + mandelic acid blend
• Precision delivery system supporting:up to ~3600 controlled drip tests, orapproximately 170 standard spray applications, extendable to ~500 sprays using the included spray ring extender.
• High-power UV excitation flashlight, providing industry-leading output for reliable fluorescence excitation even in ambient lighting conditions.
• Spray ring extender, enabling expanded coverage and extended reagent life per bottle.
• User guidance materials for surface testing and interpretation.
• Non-Toxic Reference Sample to train the users eye to the detection of lead.

The system is engineered for high test count per kit, low per-test cost, and repeated field use and long shelf life.

Use Workflow

1. Select surface suspected of containing lead.
2. Apply reagent via spray, drop, or wipe.
3. Illuminate with flashlight.
4. Observe fluorescence response.

Bright green fluorescence indicates the presence of accessible lead at the tested location. Absence of fluorescence suggests lead is not present at detectable levels or is not surface‑accessible.

Pre-Existing Fluoreseecnce does NOT INDICATE LEAD as methylammonium lead bromide is not a naturally occurring material.

Performance Characteristics

Sensitivity

Fluoro-Spec™ reliably detects nanogram-scale surface lead under practical field conditions. With optimized reagent concentration and high-output UV excitation, fluorescence is readily visible where lead-containing surface phases are present.

Throughput and Capacity

A single Fluoro-Spec™ reagent bottle supports:

• approximately 3600 drip-based tests, or
• 170 spray tests in standard configuration, expandable to ~500 spray tests with the included spray ring extender.

This high test density enables large-area screening at exceptionally low per-test cost.

Optical Performance

The included high-power UV flashlight provides excitation intensity sufficient to induce strong green fluorescence even on challenging surfaces, improving reliability compared with low-output consumer UV sources.

Specificity

The fluorescence signal arises from lead-specific perovskite formation. While surface chemistry and environmental conditions influence signal intensity, the method is inherently selective for lead, no other elements form a fluorescent provoskite with methylammonium bromide

Sensitivity

Fluoro‑Spec™ is capable of detecting nanogram‑scale surface lead under practical field conditions. Sensitivity depends on:

• lead loading,
• surface chemistry,
• reagent contact efficiency,
• optical conditions.

In conditionals where Lead Based Paint (LBP) exists on the surface, said substrate is readily detectable.

LBP dust particles are detectable down to sizes of only 40 micrometers.

Specificity

The fluorescence signal arises from lead‑specific perovskite formation. While environmental interferences can affect signal strength, the method is inherently selective for lead halide chemistry.

Limitations and Proper Use

• Fluoro‑Spec™ is a screening tool, not a quantitative assay. It detects lead semi-quantitatively which is clear to the user by the intensity of green light emitted.
• Non‑fluorescence does not guarantee absence of buried lead.
• Environmental conditions (lighting, surface roughness) can affect visibility.
• Surfaces may reflect light from the UV light in a way that looks blue to yellow.

Users should follow best practices and local regulations when responding to positive findings.

Key Scientific References

1. Holtus, T.; Helmbrecht, L.; Hendrikse, H. C.; et al. Shape-preserving transformation of carbonate minerals into lead halide perovskite semiconductors based on ion exchange/insertion reactions. Nature Chemistry 10, 740–745 (2018). DOI: 10.1038/s41557-018-0064-1. (Includes a real-time UV-illuminated conversion movie of a sand dollar converted to PbCO₃ and then converted to CH₃NH₃PbBr₃ by dripping CH₃NH₃Br solution under 365-nm UV.)
2. Wang, et al. Highly selective fluorescence turn-on determination of Pb(II) in water by in-situ enrichment of Pb(II) and MAPbBr₃ perovskite growth in sulfhydryl functionalized mesoporous alumina film. Sensors and Actuators B: Chemical 326, 128975 (2021). DOI: 10.1016/j.snb.2020.128975.

Fluoro-Spec™ is intended for screening and informational use. Confirmatory laboratory analysis is required for regulatory or legal determinations.