This invention introduces a simple and reliable method to detect harmful arsenic in water using specially designed gold nanoparticles coated with urea and functionalized with methylcobalamin (a form of Vitamin B12). The material changes how it interacts with light when arsenic is present, allowing its concentration to be measured accurately using a standard or portable spectrophotometer. It can detect arsenic in a wide range of water sources—including tap, lake, and river water—without the need for pre- treatment or filtering. The sensor works even in the presence of other common substances found in water, making it highly selective, sensitive, and suitable for both laboratory and field use.
Figure (1) Sensor device showcasing measurement of arsenic concentration in water
With the rising incidence of arsenic contamination, the rapid detection and precise measurement of its concentration have become critical challenges in ensuring the availability of safe drinking water. There is an urgent need to develop a novel nanocomposite capable of measuring arsenic concentrations, effectively serving as an accurate sensor for arsenic.
- Ultra-sensitive Detection: Detects As(III) with a lower limit of detection as low as 0.1 ppb.
- Selective to Arsenic Ions: Offers specific detection of As(III) without interference from other common ions or metals even at 1000× concentrations.
- No Pre-filtration Required: Works directly with untreated water samples, including river, lake, and tap water.
- Wide TDS Compatibility: Capable of operating across a wide TDS range (47–396 ppm), covering most natural water sources.
- Field-Ready Sensor Design: Compatible with both standard lab spectrophotometers and portable, on-board LED-based spectrometers.
A nanocomposite for sensing and measuring arsenic concentration in water, comprising methylcobalamin functionalized, urea-coated gold nanoparticles, has been proposed. The device for measuring arsenic concentration can utilize a light-emitting diode (LED) and a corresponding photodiode, which emit and receive wavelengths in the visible range, respectively. Also, the device can be a spectrophotometer. This sensor is capable of measuring arsenic concentrations in river water, lake water, and tap water with total dissolved solid(TDS) levels ranging from 47 to 396 ppm, covering almost the entire permissible range of TDS in drinking water and potentially extendable for higher TDS levels without issues.
The invention is an early prototype which has been developed and has been validated in relevant environment.
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This technology addresses a critical public health challenge by enabling the detection of toxic arsenic levels in water sources with high sensitivity and reliability. By eliminating complex preparation steps and avoiding interference from other ions, it makes arsenic testing feasible in real-world field settings. The simplicity of fabrication and the non- hazardous nature of its components ensure environmental safety. This invention holds significant promise for safeguarding drinking water quality, particularly in arsenic-affected regions, and contributes to the broader goal of water security and health equity.
Water and Wastewater Treatment, Environmental Monitoring, Public Health and Safety, Chemical and Mining Industries, Diagnostic and Sensing Devices.
- Drinking Water Quality Monitoring: For municipal bodies or NGOs ensuring arsenic-free potable water.
- Rural & Remote Water Safety: Enables on-site testing in villages and underserved areas.
- Industrial Wastewater Monitoring: Useful for detecting arsenic contamination in effluents from chemical or mining industries.
- Environmental Field Surveys: Rapid arsenic mapping of lakes, rivers, and groundwater by environmental agencies.
- Academic & Research Labs: A model system for studying LSPR-based nanocomposite sensors.
Geography of IP
Type of IP
201821030166
475726