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Raman spectroscopy is used widely by law enforcement as a field screening tool due to its speed, selectivity and ease of use. The majority of materials can be identified by the Raman signature, as they exhibit sharp distinctive peaks serving as a molecular fingerprint. However, many street and real-world samples are dark in color and not pure. The dark color, often due to impurities, gives rise to fluorescence that interferes with the Raman measurement. One method to suppress the fluorescence of a sample and enhance the Raman activity / signal is by the use of Surface-Enhanced Raman Spectroscopy (SERS).

At a crime scene, a police officer collects a fiber sample that may prove to be invaluable evidence in identifying a criminal or exonerating an innocent person. In recent years, Raman spectroscopy has been studied extensively for forensic fiber analysis because of the high selectivity of Raman signatures, non-destruction nature of the test, and the ability to conduct the analysis without any sample preparation. The Raman spectrum can be measured directly on fabrics or fibers mounted on glass slide with very little interference from the mounting resin or the glass.

The TacticID®-1064 ST is a 1064 nm handheld Raman system designed for law enforcement officials, first responders, and customs and border protection officers for rapid field identification of illicit substances such as narcotics, explosives, and other suspicious materials. The TacticID-1064 ST is specially designed with see-through Raman functionality to measure materials through both transparent and opaque containers. These through-barrier measurements remove the need for active sampling of potentially dangerous compounds such as fentanyl, leading to safer operations and reduced wait time for clear results.

In this case study, a suspected counterfeit Adderall pill was measured directly with a TacticID Mobile using a point-and-shoot adapter. The spectra of the suspected couterfeit pill was found to contain cellulose and caffeine, but not the active ingredient. The TacticiD Mobile with 1064-nm laser excitation provides fluorescence suppression, giving those on the front lines a tool in the fight against dangerous counterfeit drugs.

The determination of cyanide is very important not only in electroplating baths and when decontaminating wastewater but, due to its high toxicity, also in water samples in general. Concentrations of 0.05 mg/L CN- can already be lethal for fish. This Bulletin describes the determination of cyanide in samples of different concentrations by potentiometric titration. Chemical reactions: 2 CN- + Ag+ → [Ag(CN)2]- [Ag(CN)2]- + Ag+ → 2 AgCN

The determination of the acid number plays a significant role in the analysis of petroleum products. This is manifested in the numerous standard procedures in use over the world (internal specifications of multinational companies, national and international specifications of ASTM, DIN, IP, ISO, etc.). These procedures differ mainly in the composition of the used solvents and titrants.This bulletin describes the determination of the acid number in petroleum products by applying different types of titration.The potentiometric determination is described according to ASTM D664, the photometric according to ASTM D974 and the thermometric titration according to ASTM D8045.

This Application Bulletin describes the determination of the total acid number in various oil samples by catalytic thermometric titration as per ASTM D8045.

The International Standard ISO 17463 describes the determination of the anticorrosive properties of high impedance organic protective coatings on metals. This technique uses cycles composed of electrochemical impedance spectroscopy (EIS) measurements, cathodic polarizations and potential relaxation. This application note shows the compliance of the Metrohm Autolab PGSTAT M204 and flat cell with the standard ISO 17463.

A reference electrode has a stable and well-defined electrochemical potential (at constant temperature), against which the applied or measured potentials in an electrochemical cell are referred. A good reference electrode is therefore stable and non-polarizable. In other words, the potential of such an electrode will remain stable in the used environment and also upon the passage of a small current. This application note lists the most used reference electrodes, together with their range of use.

Here, the most common circuit elements for EIS are introduced which may be assembled in different configurations to obtain equivalent circuits used for data analysis.

In the application note AN-EIS-004 on equivalent circuit models, an overview of the different circuit elements that are used to build an equivalent circuit model was given. After identifying a suitable model for the system under investigation, the next step in the data analysis is estimation of the model parameters. This is done by the non-linear regression of the model to the data. Most impedance systems come with a data-fitting program. In this application note, the way NOVA is uses to fit the data is shown.

In this application note, the advantage of recording the raw time domain data for each individual frequency during an electrochemical impedance measurement is described.

Electrochemical impedance spectroscopy (EIS) is a powerful technique which provides information about the processes occurring at the electrode-electrolyte interface. The data collected with EIS are modeled with a suitable electrical equivalent circuit. The fitting procedure will change the values of the parameters until the mathematical function matches the experimental data within a certain margin of error. In this Application Note, some suggestions are given in order to get acceptable initial parameters and to perform an accurate fitting.

Specialty chemicals have to fulfill multiple quality requirements. One of these quality parameters, which can be found in almost all certificates of analysis and specifications, is the moisture content. The standard method for the determination of moisture content is Karl Fischer titration.This method requires reproducible sample preparation, chemicals, and waste disposal. Alternatively, near-infrared spectroscopy (NIR) can be used for the determination of moisture content. With this technique, samples can be analyzed without any preparation and without using any chemicals.

Fentanyl, a powerful synthetic opioid, is illegally distributed worldwide. Overdosing can be fatal, causing symptoms like stupor, pupil changes, cyanosis, and respiratory failure. Just 2 mg of fentanyl can be lethal, depending on factors like body size and past usage. Given its severe impact, identifying and detecting fentanyl is crucial, as it has become a major public health crisis. Combining electrochemical surface-enhanced Raman spectroscopy (EC-SERS) with screen-printed electrodes (SPEs) offers a fast, effective, and precise method for detecting fentanyl.

Identification of unknown materials in the field can be a complicated affair, especially in critical situations, where speed, safety, and ease-of-operation are essential. Mira DS, Metrohm Raman’s handheld Raman analyzer, and the intelligent Universal Attachment (iUA) give the user automated Content ID capabilities. Content ID achieves through container identification of unknown materials quickly, easily, and safely.

Handheld Raman spectrometers are valued for their ability to provide onsite material identification in seconds. In the case of combination pharmaceuticals, a single tablet contains more than one active ingredient in different proportions. MIRA DS is uniquely capable of identifying multiple compounds in such tablets by using Raman to identify the major component and SERS (surface-enhanced Raman spectroscopy) for the minor component. This application describes quick, dual analysis of a prescription medication containing acetaminophen and hydrocodone. The application is easily extrapolated to the study of street drugs.

Yaba, produced in Southeast Asia, is a popular drug of abuse and is actively targeted by police squads. Two strong and highly addictive stimulants make up Yaba: caffeine, which comprises up to 60% of each tablet, and methamphetamine at approximately 20%. Identifying these two active ingredients in different proportions in a colorful tablet with other excipients could be an analytical nightmare. With handheld Raman, bulk material identification is achieved in seconds onsite with simple point-and-shoot analysis. SERS (surface-enhanced Raman spectroscopy) analysis is used to detect the minor component in mixtures without interference from fillers, dyes, and coatings. MIRA DS is uniquely capable of both analyses—Raman testing positively identifies caffeine in Yaba, while methamphetamine can be detected with SERS sampling. This application describes quick, dual analysis of Yaba tablets with MIRA DS.

Raman analysis of fentanyl-soaked paper, SERS detection range for fentanyl on paper, and real-world example of fentanyl identification.

With MISA and MIRA, easy-to-use test kits and flexible sampling allow rapid and accurate interrogation of suspect materials with minimal time, training, and expense.

Modern recreational use of DMT (N,N-Dimethyltryptamine) is growing and although it is legally protected in some countries, new legislation attempts to reduce its abuse and associated adverse health effects. MIRA XTR DS from Metrohm Raman provides rapid and sensitive detection of DMT in the field.

Forensic institutes examine terrorist attacks and warfare agents via trace detection analysis of the used explosives and their residuals. Of particular importance is the acquisition of «chemical fingerprints» for criminal investigation departments and governmental security agencies. Institutes for public health and environmental protection analyze such compounds that can contaminate the underlying soil and infiltrate ground water. Forensic investigation with ion chromatography (IC) using suppressed conductivity detection allows a sensitive and robust determination of anionic contaminants such as chlorate, thiosulfate, thiocyanate, and perchlorate next to the common inorganic anions over a broad concentration range.

Knowledge of the water content in lubricating oils, additives, and similar products is important in the manufacturing, purchase, sale, or transfer of petroleum products to help estimate their quality and performance characteristics. Monitoring the water content in such products can prevent damage to infrastructure and ensure safe operation by avoiding corrosion processes and subsequent engine wear. This White Paper explains the easy determination of moisture in petroleum samples by coulometric Karl Fischer titration according to the three procedures outlined in ASTM Method D6304. A comparison is given between the procedures to determine which is most suitable for different sample types.

Like any defense and security professional, border agents must quickly and accurately identify suspicious substances at the point of contact. When that substance is fentanyl, which is deadly in microdoses, the stakes are even higher. The Mira DS handheld Raman system from Metrohm Raman offers safe, no-contact identification of over 200 fentanyl analogues. Mira DS protects border agents, while they protect citizens from deadly narcotics, drug smugglers, and illegal entry of goods.

Ion chromatography mass spectrometry (IC-MS) is a powerful tool that can handle many challenging analytical tasks which cannot be performed adequately by IC alone. IC-MS is a robust, sensitive, and selective technique used for the determination of polar contaminants like inorganic anions, organic acids, haloacetic acids, oxyhalides, or alkali and alkaline earth metals. After separation of the sample components via IC, mass selective detection guarantees peak identity with low detection limits. The inclusion of automated Metrohm Inline Sample Preparation (MISP) allows not only water samples, but also chemicals, organic solvents, or post-explosion residues to be readily analyzed without need for extensive manual laboratory work. This White Paper explains the benefits of IC-MS over IC in certain cases, the hyphenation of IC and different MS systems, as well as related norms and standards.

Handheld Raman is ever evolving. The combination of large libraries, a compact and easy-to-use system, and predictive Hazmat software make MIRA DS a powerful tool for defense and security professionals. Identify on-site materials, get hazard information, and make quick decisions about response to dangerous situations.

Trong White Paper này, bạn sẽ tìm hiểu về MIRA XTR DS – hệ thống Raman cầm tay nhỏ nhất, thông minh nhất, linh hoạt nhất với các thư viện lớn nhất hiện có trên thị trường! MIRA XTR DS có tất cả các lợi ích định tính Raman 785 nm: kích thước nhỏ gọn, công suất laser thấp, bảo quản mẫu, tuổi thọ pin dài... giờ đây có khả năng loại bỏ huỳnh quang. Ngoài ra, độ nhạy và độ phân giải được cải thiện so với các hệ thống 1064 nm. Điều này mở ra những khả năng mới cho Raman 785 nm, bao gồm các vật liệu có màu đậm, tá dược thông thường, vật liệu bất hợp pháp, v.v.

It is widely accepted that prolonged exposure to hexavalent chromium compounds can have dire health effects. This has led to increased regulation of chromium-containing products and greater demand for technologies that can positively identify hexavalent chromium in potential matrices. These include paints, dyes, and primers, which can pose a problem for interrogation with Raman, as strongly colored materials often exhibit fluorescence when stimulated at 785 nm. Fluorescence can obscure the Raman signal and prevent positive identification. MIRA XTR DS provides all the functionality of handheld material ID with a new capability that selectively eXTRacts the Raman signal from fluorescent materials. Fluorescence rejection at 785 nm provides higher sensitivity and resolution than 1064 nm systems, as well as a much wider scope of applications amenable to Raman spectroscopy. MIRA XTR DS offers a comprehensive and versatile material ID test solution for field operations.