Portable Spectrophotometer for Real-Time Copper and Silver Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for monitoring copper and silver levels in water, particularly in real-time, are inefficient and lack effective field testing solutions, often requiring specialized equipment and lengthy laboratory analysis, which hinders the control of Legionella bacteria in plumbing systems.
Innovation Solution
A method and apparatus for detecting copper and silver in water using a spectrophotometer-based system with specific chemical reagents, including a 2% nitric acid solution, buffer solutions, and indicators, allowing for real-time detection down to 50 ppb silver and 200 ppb copper, with a portable monitoring device that automates the process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional laboratory methods (ICP testing, sample plating) are used to detect copper and silver levels, then measurement precision is improved, but loss of time worsens significantly
Solution Approach 1:
The patent replaces complex mechanical laboratory instrumentation (ICP mass spectrometers, incubators for sample plating) with a simplified optical detection system using colorimetric reagents and a spectrophotometer. This substitution enables rapid field testing while maintaining sufficient precision for regulatory compliance, reducing testing time from weeks to minutes without requiring centralized laboratory facilities.
Solution Approach 2:
The patent transforms the detection approach by changing the physical-chemical parameters of the analysis. Instead of measuring atomic emission spectra (ICP) or bacterial growth over days (plating), the method uses colorimetric reactions where copper and silver ions form colored complexes with specific reagents (neocuproine for copper, cadion for silver). These color changes can be measured immediately with a spectrophotometer, enabling rapid results while maintaining detection precision at regulatory levels.
2Measurement precision
If specialized field instrumentation and caustic chemicals are used for detection, then measurement precision is improved, but device complexity and ease of operation worsen
Solution Approach 1:
The patent extracts the essential detection function from complex laboratory instrumentation by isolating the key chemical reactions and transferring them to field-deployable test kits. The method removes unnecessary complexity by using simple colorimetric reagents that can be stored in vials and added directly to water samples, eliminating the need for sophisticated equipment while maintaining detection precision through standardized reagent formulations and controlled reaction conditions.
Solution Approach 2:
The patent employs disposable test kits containing pre-measured reagents in stable formulations. Each kit includes vials of colorimetric reagents (neocuproine for copper, cadion for silver) and buffers that are prepared in advance and sealed for field use. This approach replaces expensive, complex instrumentation with simple, single-use test systems that are easy to deploy and eliminate the need for maintenance of sophisticated equipment, while maintaining measurement precision through controlled reagent chemistry.
3Ease of operation
If operator-dependent field testing methods are used, then ease of operation is improved, but measurement precision worsens due to variability
Solution Approach 1:
The patent prepares all critical parameters in advance during reagent manufacturing: precise chemical compositions, buffered pH levels, and optimized reagent concentrations are established before field deployment. The colorimetric reagents (neocuproine, cadion) are formulated with buffers and stabilizers that maintain consistent reaction conditions across different operators and environments. This preliminary standardization ensures that field operators can perform simple addition and measurement steps while achieving laboratory-quality precision and result consistency.
Solution Approach 2:
The test system incorporates self-regulating chemical mechanisms that automatically compensate for operator variability. The buffered reagent solutions maintain stable pH levels without requiring operator adjustment, and the colorimetric reactions proceed to completion based on fixed kinetic parameters. The spectrophotometer automatically measures absorbance at specific wavelengths and calculates concentrations using pre-programmed calibration curves, eliminating subjective interpretation and ensuring consistent results regardless of operator experience level.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables accurate and rapid detection of copper and silver levels in water, facilitating effective control of Legionella bacteria by providing a reliable, on-site monitoring solution that matches laboratory precision.
Implementation Method 1
reading the absorbance of the sample using a spectrophotometer with an approximate target peak of 515 nm
Data Source
AI summary
Disclosed is a real-time method for detecting copper and silver in water in parts per billion. Total silver is detected by adding a nitric acid solution to the sample; after the silver is digested, adding a buffer solution comprising water, sodium bicarbonate, sodium carbonate and EDTA to the sample; adding an indicator comprising Cadion 2B, EtOH, and Triton X-100 to the sample; then reading the absorbance of the sample after light with an approximate target peak of 515 nm is sent through the sample; and determining the silver concentration by comparing the absorbance of the sample to the absorbances of known silver standards. Total copper is detected by adding a nitric acid solution to the sample; after the copper is digested, adding a buffer/indicator solution to the sample, where the solution comprises water, sodium citrate dihydrate, hydroxal amine hydrochloride and bathocuproine disulfonate; after one minute, reading the absorbance of the sample after light with an approximate target peak of 480 nm is sent through the sample; and determining the copper concentration by comparing the absorbance of the sample to the absorbances of known copper standards. A monitoring device for determining the level of copper or silver in a sample implements the disclosed methods.