This invention introduces a method for ultra-sensitive and real-time detection of chemical explosives using surface-enhanced Raman spectroscopy (SERS). By cooling a colloidal solution of metal nanoparticles under a thermal gradient, controlled aggregates called Soret colloids are formed. These colloids provide significant Raman signal enhancements, enabling detection of explosives at single-molecule levels in solutions and ppm levels in gas phase. The method allows for direct ambient sampling, reliable quantification, and the first demonstration of direct gas-phase TNT detection using SERS. This innovation paves the way for commercialization in defense and security sectors.
Figure 1: (a) Absorption spectra of various nanoparticles investigated, exhibiting clear and distinct peaks associated with the surface plasmon resonance absorption. (b) Photographs of the as-prepared nanoparticle colloidal solutions. (2) Domain separation and subsequent formation of Domains 1, 2 and 3 in nanoparticle colloidal solutions, under the influence of thermal gradient for (i) Au-15, (ii) Ag-60, (iii) Au-5 and (iv) Au@PA
The increasing use of improvised explosive devices (IEDs) in military, security, defense, and other applications poses a significant threat to global safety. Current detection methods often lack the sensitivity, reliability, and real-time capability needed to identify trace amounts of chemical explosives. Existing techniques may require elaborate sample preparation, sophisticated instrumentation, or are prone to interference from similar substances. There is a need for a highly sensitive, reliable, and real-time detection method for chemical explosives that can be deployed in various environments without extensive preparation or complex equipment.
- Soret Colloids Formation: Controlled nanoparticle clusters formed via cooling under a thermal gradient.
- Ultra-Sensitive Detection: Detects single molecules in liquid and ppm levels in gas phase.
- Direct Gas-Phase Detection: First method for real-time SERS detection of TNT in gas phase.
- Reliable Signals: Provides reproducible and quantifiable SERS signals.
- Non-Invasive Sampling: Direct ambient sampling without elaborate preparation.
- Versatile Applicability: Works with various nanoparticles and analytes for broad detection capabilities.
The prototype consists of colloidal solutions of various metal nanoparticles (e.g., Ag-60, Au-15) cooled under a thermal gradient to form Soret colloids. These were tested for SERS detection using custom experimental setups, including a gas-phase detection rig with carrier gas bubbling through TNT. Reproducibility was confirmed across multiple samples using analytes like R6G and TNT.
The invention demonstrates a working method for synthesizing metal nanoparticle aggregates (Soret colloids) and successfully applies them for detecting analytes in both liquid and gas phases using SERS. Real-time detection of TNT gas at ppm levels has been experimentally validated. The patent is granted and ready for licensing.
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- Enhanced Security: Provides reliable methods for detecting explosives, improving public safety and reducing the risk of terrorist attacks.
- Defense Capabilities: Strengthens military and defense operations with real-time detection of chemical explosives
- Environmental Monitoring: Enables detection of hazardous chemicals in the environment, aiding in pollution control and environmental protection.
- Emergency Response: Enhances the capabilities of emergency services to quickly and accurately identify threats, improving response times and effectiveness.
Explosive Detection, Chemical Warfare Agent Detection, Environmental Hazard Monitoring, Forensic Analysis, Airport and Border Security.
Geography of IP
Type of IP
201621042432
397004