Our gold, silver and nanosponge gold/silver SERS substrates let you make fast, repeatable SERS measurements for the identification and quantification of SERS-active analytes.Typical applications include trace level detection of explosives and narcotics and precision screening of food ingredients for controlled additives such as melamine and pesticides. SERS substrates also can be used for authentication and anti-counterfeiting applications using SERS-active taggants. Here are some key applications:
- Detection of explosives. Being able to identify trace levels of explosives allows us to better screen for threats at security checkpoints or on the battlefield.
- Detection of narcotics. Fast identification of drugs in the field is a real boon for those combating drug-related crime. Often only small residues of a sample can be collected from a crime scene. SERS also opens up a potential route for fast roadside drug screening of drivers using saliva samples.
- Food safety. Certain additives such as melamine found in milk powder can be extremely harmful even at very low concentrations. Using SERS, we can qualify and quantify the level of dangerous trace elements in our food supply chain.
- Anti-counterfeit tagging. High value products that are subject to duties and taxes — petrol is one example — are often the target of piracy and fraud. By adding a small amount of a SERS-active taggant to the unadulterated product, detecting the presence of the taggant becomes an instant indicator of authenticity.
- Biological research. SERS can be used to identify and characterize biological samples including proteins, DNA and bacteria.
|Laser wavelength (nm)||RAM-SERS-AU (gold)||RAM-SERS-AG (silver)||RAM-SERS-SP (nanosponge)|
|638||Malachite green, crystal violet||Rhodamine B||Explosives|
|785||BPE, E. coli, pesticides||Melamine||—|
Ocean Optics introduces an innovative manufacturing method for SERS substrates. SERS amplifies the Raman effect by creating a plasmon resonance field. Using precisely controlled gold nanoparticles, Ocean Optics SERS substrates can amplify very weak Raman signals by many orders of magnitude, which is critical for trace level detection. Unlike many existing SERS products on the market, Ocean Optics SERS substrates are easy to use, affordable and can be mass produced with high repeatability for routine deployment in the lab or field.
Advantages of Ocean Optics SERS Substrates
- High sensitivity. Substrates deliver great results and have demonstrated superior sensitivity for a range of analytes when tested against competitor substrates
- Great stability. Highly stable substrates require no special handling and can be stored at room temperature
- Reliable reproducibility. Highly reproducible and easily scaled manufacturing methods enable sensitive measurements at an affordable price
- Customized form factors. Unique production techniques can be tailored to impart specificity to particular analytes (on demand) and custom form factors such as swabs and coatings
- Easy to use. For great flexibility, substrates work reliably with the complete range of Ocean Optics Raman instruments
SERS Substrates Options
|Slide dimensions:||25.4 x 76.2 x 1 mm||25.4 x 76.2 x 1 mm||25.4 x 76.2 x 1 mm|
|SERS active area:||5.5 mm diameter circle||5.5 mm diameter circle||4 x 4 mm square|
|SERS active chemistry:||Gold (Au) Nanoparticles||Silver (Ag) Nanoparticles||Gold/Silver Film|
|Slide material:||Borosilicate Glass||Borosilicate Glass||Borosilicate Glass|
|Raman excitation wavelength:||785 nm||532 nm||638 nm|
|Storage lifetime:||1.5 months||1 month||6 months|
|Laser power:||≤20 mW||≤20 mW||≤100 mW|
|Volume of analyte:||15 µL||15 µL||10 µL|
ppm to ppb level sensitivity for wide range of analytes
Real-World Applications Made Easy and Reliable
Ocean Optics SERS substrates are versatile, general-purpose measurement substrates for many applications. The table below suggests the limit of detection for the QE Pro Raman spectrometer with SERS substrates, using a 785 nm excitation laser with a 1 second integration time. While each analyte will behave differently, these results show how our SERS substrates are a great choice for general-purpose SERS measurements.
|Material||Why Do I Want to Detect Trace Levels?||
LOD with QE-Pro*
|BPE||BPE can be used as a taggant in fuel as well as in biological samples.||0.1 fg||30 fg|
|TNT||The threat of terrorism means the need for quick screening for trace levels of explosions is greater than ever.||5 ng||30 pg|
|Melamine||Poisonous to humans, especially babies and children at very low levels (<1 ppm).||5 pg||0.1 pg|
*Please note that the LOD will depend on the sample and spectrometer used and that these are provided as guidelines only.
SERS Analytes Library – Limits of Detection
|Analyte||Classification||Lowest detectable concentration determined|
|1,2-bis(4-pyridyl)ethylene (BPE)||Taggant / Marker||0.2 ppb|
|4-mercaptobenzoic acid||Taggant / Marker||15 ppb|
|4-mercaptopyridine||Taggant / Marker||0.1 ppm|
|2-naphthalenethiol||Taggant / Marker||0.2 ppm|
|1,10-phenantroline||Taggant / Marker||0.2 ppm|
|1,2-Bis(4-pyridyl)ethane (BPYE)||Taggant / Marker||18 ppm|
|4,4’-Trimethylenedipyridine (TMDP)||Taggant / Marker||20 ppm|
|1,4-Diethynylbenzene (DEB)||Taggant / Marker||13 ppb|
|Cocaine||Illict drug||340 ppm|
|THC||Illict drug (Cannabis)||3000 ppm|
|2-propranolol||Beta blocker||30 ppm|
|ipratropium bromide||Bronchodilator||4000 ppm|
|nicotinamide||B vitamin||12 ppm|
|crystal violet||Fungicide||4 ppb|
|malachite green||Fungicide||4 ppb|
|thiram||Fungicide, ectoparasiticide, and animal repellent||24 ppm|
|malathion||Organophosphate insecticide||1 ppm|
|melamine||Food adulterant||10 ppm|
|cyanuric acid||Metabolite of food adulterant melamine||1000 ppm|