Raman imaging studies on the stability of Paracetamol tablets under different storage conditions

The applicability of Raman imaging for pharmaceutics production ranges from the characterization of pharmaceutical formulations, kinetic processes in drug delivery to the rapid detection and identification of counterfeit drugs/contaminants. Acetaminophen (Paracetamol, APAP) is an analgesic and antipyretic drug and one of the most consumed medicines worldwide. On the other hand, the compound 4-aminophenol (4-AP) is a hydrolytic product of APAP with nephrotoxicity and teratogenic effects. In this work, we have explored for the first time Raman imaging methods to characterize the main components of commercial APAP tablets (APAP-tablets) and to inquire about the potential of this optical technique to identify 4-AP in APAP tablets, which have been previously spiked with such contaminant. The laboratorial treated APAP-tablet samples were subjected to different temperature, humidity and sunlight exposure conditions, mimicking storage conditions, and then the Raman spectra and images were collected to monitor changes that might occur in those conditions. Although the lower limit of detection of 4-AP in APAP-tablets is above the minimum levels established by Pharmacopoeias (0.005 %), this research demonstrates that Raman imaging still allows the detection of small amounts of the contaminant, thus opening perspectives for exploring this technique for characterizing APAP products.publishe

Progress in low-field benchtop NMR spectroscopy in chemical and biochemical analysis

The employment of spectroscopically-resolved NMR techniques as analytical probes have previously been both prohibitively expensive and logistically challenging in view of the large sizes of high-field facilities. However, with recent advances in the miniaturisation of magnetic resonance technology, low-field, cryogen-free “benchtop” NMR instruments are seeing wider use. Indeed, these miniaturised spectrometers are utilised in areas ranging from food and agricultural analyses, through to human biofluid assays and disease monitoring. Therefore, it is both intrinsically timely and important to highlight current applications of this analytical strategy, and also provide an outlook for the future, where this approach may be applied to a wider range of analytical problems, both qualitatively and quantitatively

Development and application of spectroscopy techniques for monitoring hydrate and corrosion risks

Pipelines are used to transport hydrocarbons from production wells to different locations for various purposes (e.g. processing, refinery, power generation, etc.) and CO2-rich fluids from the emission sources for disposal in suitable geological storage sites. The presence of water in such hydrocarbon and/or CO2 transport pipelines may result in corrosion, ice and/or gas hydrate formation and even pipeline blockage, so the fluid system should meet certain dehydration and/or inhibition requirements. This work describes the development and application of different spectroscopic (UV-VIS and NIR) methods for identifying and controlling flow assurance issues relating to gas hydrate and corrosion. For hydrates, a Fourier Transform Near-Infrared (FTNIR) spectroscopy method using chemometric models was developed to measure the concentration of main hydrocarbon gases (Methane through butanes) under in-situ pressure (up to 13.8 MPa). This approach was then used for detecting initial signs of hydrate formation based on reduction in the concentration of some preferential components in the gas phase. Furthermore, injection of hydrate inhibitors based on the calculated/measured hydrate phase boundary, water cut, pressure and temperature conditions, and the amount of inhibitor lost to non-aqueous phases is a commonly used method for avoiding gas hydrates problems. Thus, it is crucial to monitor salt and inhibitor concentration in the fluids along the pipeline and/or downstream in order to optimise the injection rate. To address this requirement, a novel method was developed by combining UV and NIR spectra to predict the concentration of salt and hydrate inhibitors (THIs and KHIs) simultaneously in aqueous solutions. In the case of corrosion, the potential of visible spectroscopic technique was investigated for determining the pH in CO2/ CO2-rich mixtures saturated water, and CO2/ CO2-rich mixtures saturated NaCl solutions at pressures up to 15 MPa and temperature ranges from 293.15 to 323.15 K. Furthermore, we described and evaluated a model that uses a robust thermodynamic basis for describing the solubility of gases in the aqueous phase and Pitzer’s theory for determining the activity coefficients of the ionic species involved. The model was tested in concentrated NaCl solutions under CO2 pressure at realistic industrial operating temperatures. The developed spectroscopic techniques were experimentally evaluated at lab conditions. Results show that these techniques can be applied to detect initial signs of hydrate formation, to optimise hydrate inhibitor injection rate, and to measure the pH of CO2 saturated H2O/brine systems in the downhole/wellbore/pipeline region

Definition of a near real time microbiological monitor for space vehicles

Efforts to identify the ideal candidate to serve as the biological monitor on the space station Freedom are discussed. The literature review, the evaluation scheme, descriptions of candidate monitors, experimental studies, test beds, and culture techniques are discussed. Particular attention is given to descriptions of five candidate monitors or monitoring techniques: laser light scattering, primary fluorescence, secondary fluorescence, the volatile product detector, and the surface acoustic wave detector

4-Fluoroamphetamine (4-FA). A Critical Review Report

1-(4-Fluorophenyl)propan-2-amine (4-fluoroamphetamine, 4-FA) underwent a critical review in November 2015 at the 37th meeting of the WHO Expert Committee on Drug Dependence. The Committee recommended that 4-FA not be placed under international control at that time due to insufficiency of data regarding dependence, abuse and risks to public health but be kept under surveillance. This review represents an update. 4-FA is a psychomotor stimulant first synthesized in the early 1940s. The European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) received the first formal notification of the detection of 4-FA in Europe in December 2008 although its presence has been noted since at least 2007. In Europe, it has been found in tablets sold as ‘ecstasy’/MDMA, paste or powder sold as amphetamine. It has also been detected as an adulterant present in other illicit controlled substances. The EMCDDA has been notified of seizures from various locations in Europe since 2008. In the Netherlands, 4-FA has recently established itself as a drug of choice (powdered form, tablets and capsules) in a subpopulation of recreational drug users associated with clubs and music festivals. 4- FA appears to be most commonly administered orally or by nasal insufflation (snorting). Data indicate that 4-FA may be able to inhibit monoamine oxidase and that it functions as a substrate-type releasing agent of dopamine, norepinephrine and serotonin. It has been shown to display amphetamine-like features in vivo and in vitro, which suggests that abuse liability might extend to humans. Further research is warranted to investigate the extent to which 4-FA displays a potential dependence in both animals in humans. Case report data in the scientific literature that unambiguously confirm a causal relationship between adverse effects of 4-FA and its presence in biofluids are limited to only a relatively small number of cases. In cases where this information is available, reported clinical features were associated with those of a sympathomimetic toxidrome. Information about a global perspective is missing. However, reports received from data monitoring systems in the Netherlands indicate increased use and popularity alongside increased numbers of notifications associated with severe adverse drug effects including serious cardiovascular toxicity. Following a risk assessment carried out by the Dutch Centre for the Assessment and Monitoring of new drugs (CAM), it was concluded that the risk to individual health was small to moderate but with high risk for acute toxicity especially in subpopulations associated with clubbing. The risk to public health was deemed moderate to large based on rising trends in use number of health incidents. The overall risk score of 4-FA was considered high, which led to 4-FA being placed under legislative control

Chemical Information Bulletin

Periodic supplement for "the regular journals of the American Chemical Society," containing annotated bibliographies of chemical documentation literature as well as information about meetings, conferences, awards, scholarships, and other news from the American Chemical Society (ACS) Division of Chemical Literature