Performance Characteristics of Mass Spectrometry-Based Analytical Procedures for Quantitation of Nitrosamines in Pharmaceuticals: Insights from an Inter-laboratory Study.

With the discovery of carcinogenic nitrosamine impurities in pharmaceuticals in 2018 and subsequent regulatory requirements for risk assessment for nitrosamine formation during pharmaceutical manufacturing processes, storage or from contaminated supply chains, effective testing of nitrosamines has become essential to ensure the quality of drug substances and products. Mass spectrometry has been widely applied to detect and quantify trace amounts of nitrosamines in pharmaceuticals. As part of an effort by regulatory authorities to assess the measurement variation in the determination of nitrosamines, an inter-laboratory study was performed by the laboratories from six regulatory agencies with each of the participants using their own analytical procedures to determine the amounts of nitrosamines in a set of identical samples. The results demonstrated that accurate and precise quantitation of trace level nitrosamines can be achieved across multiple analytical procedures and provided insight into the performance characteristics of mass spectrometry-based analytical procedures in terms of accuracy, repeatability and reproducibility.

Inorganic analysis of falsified medical products using X-ray fluorescence spectroscopy and chemometrics.

Falsified medical products are increasingly prevalent on markets, threatening the health of patients. This study describes the benefits of Energy Dispersive X-Ray Fluorescence (ED-XRF) spectroscopy and chemometrics thus highlighting the importance of conducting inorganic analyses on falsified products. The XRF spectrum is a fingerprint containing the contribution of all chemical substances included in a suspect sample's formulation. Multivariate analysis of XRF spectra, using a properly validated classification model, allows for the authentication of suspect samples. The method is rapid, relying on multi-elemental measurements and involving minimal sample preparation. This methodology provided valuable information about samples inorganic composition and enabled the detection of falsifications of several sample types, including medicine, food supplement and cosmetic samples. Five suspect samples of Plavix® were investigated, and their XRF spectra were studied using chemometrics (Principal Component Analysis and Soft Independent Modelling of Class Analogies). A classification model was validated with positive and negative samples, and four suspect samples were identified as being falsified, whilst the fifth was concluded as an authentic medicine. ED-XRF spectroscopy was also applied on another medicine, a food supplement and three cosmetic samples, and high level of zinc was detected in the second sample and mercury was identified in the last. Estimation of the zinc content was possible using the fundamental parameters method. ED-XRF spectroscopy allows the analyst to conclude on the falsification of the samples and then to assess the harm to patient health.

Raman chemical imaging for spectroscopic screening and direct quantification of falsified drugs.

Falsified drugs are a threat to the health of patients. The analytical control of such products contributes to the fight against this global issue. Raman chemical imaging is a method that relies on consecutive measurements at the surface of a sample, combining spectroscopy, microscopy and chemometrics. This article explores the capabilities of this analytical technique proposing an innovative methodology with spectroscopic screening for the identification of chemical compounds and the direct quantification of the active substance (without prior calibration). Two chemometric methods were used: Multivariate Curve Analysis - Alternate Least Squares for the qualitative analysis and Direct Classical Least Squares for the quantitative analysis. The methodology was optimized with samples prepared in the laboratory and validation parameters were studied. The methodology was then applied to real (authentic and falsified) samples of Viagra® and Plavix®. Despite the presence of fluorescence emission in some samples, the methodology succeeded in the detection of active pharmaceutical ingredients, and in the discrimination of three salts of clopidogrel (in generic formulations of Plavix®). The quantitative deviation from the reference method ranged from -15% to +24% of the active substance content. This deviation may be considered to be acceptable since it is sufficient for assessing the risk to the health of patients and for quickly alerting the health authorities.

Fighting falsified medicines: The analytical approach.

Given the harm to human health, the fight against falsified medicines has become a priority issue that involves numerous actors. Analytical laboratories contribute by performing analyses to chemically characterise falsified samples and assess their hazards for patients. A wide range of techniques can be used to obtain individual information on the organic and inorganic composition, the presence of an active substance or impurities, or the crystalline arrangement of the formulation's compound. After a presentation of these individual techniques, this review puts forward a methodology to combine them. In order to illustrate this approach, examples from the scientific literature (products used for erectile dysfunction treatment, weight loss and malaria) are placed in the centre of the proposed methodology. Combining analytical techniques allows the analyst to conclude on the falsification of a sample, on its compliance in terms of pharmaceutical quality and finally on the safety for patients.

Investigation of the composition of anabolic tablets using near infrared spectroscopy and Raman chemical imaging.

The use of performance enhancing drugs is a widespread phenomenon in professional and leisure sports. A spectroscopic study was carried out on anabolic tablets labelled as 5 mg methandienone tablets provided by police departments. The analytical approach was based on a two-step methodology: a fast analysis of tablets using near infrared (NIR) spectroscopy to assess sample homogeneity based on their global composition, followed by Raman chemical imaging of one sample per NIR profile to obtain information on sample formulation. NIR spectroscopy assisted by a principal components analysis (PCA) enabled fast discrimination of different profiles based on the excipient formulation. Raman hyperspectral imaging and multivariate curve resolution - alternating least square (MCR-ALS) provided chemical images of the distribution of the active substance and excipients within tablets and facilitated identification of the active compounds. The combination of NIR spectroscopy and Raman chemical imaging highlighted dose-to-dose variations and succeeded in the discrimination of four different formulations out of eight similar samples of anabolic tablets. Some samples contained either methandienone or methyltestosterone whereas one sample did not contain an active substance. Other ingredients were sucrose, lactose, starch or talc. Both techniques were fast and non-destructive and therefore can be carried out as exploratory methods prior to destructive screening methods. Copyright © 2015 John Wiley & Sons, Ltd.

Determination of 19 antiretroviral agents in pharmaceuticals or suspected products with two methods using high-performance liquid chromatography.

Three classes of antiretroviral agents are usually available for the treatment of HIV infection: nucleoside reverse transcriptase inhibitors (IN), non-nucleoside reverse transcriptase inhibitors (INN) and protease inhibitors (IP). Two methods by reversed-phase liquid chromatography were developed for the analysis of 19 antiretroviral molecules belonging to these three therapeutic classes and used in medicinal products. Both of these HPLC techniques use a C18 column and UV detection. The first method is for IN family analysis and allows eight molecules to be separated: zalcitabine, lamivudine, amdoxovir, emtricitabine, didanosine, stavudine, zidovudine and abacavir. The second method is for INN and IP family analysis and allows 11 molecules to be separated: fosamprenavir, nevirapine, indinavir, amprenavir, saquinavir, atazanavir, ritonavir, lopinavir, efavirenz, nelfinavir and tipranavir. The combination of these two methods makes possible the quality control of mono-, bi- or tri-therapy pharmaceutical products and the detection of illegal products sold particularly in developing countries.