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This paper presents a systematic literature review on the detection of new psychoactive substances (NPS) in prison settings. It includes the most frequently reported NPS classes, the routes and forms used for smuggling, and the methods employed to analyse biological and non-biological samples. The search was carried out using MEDLINE (EBSCO), Scopus (ELSEVIER), PubMed (NCBI), and Web of Science (Clarivate) databases, along with reports from the grey literature in line with the PRISMA-S guidelines. A total of 2708 records were identified, of which 50 met the inclusion criteria. Findings showed the most prevalent NPS class reported in prison was synthetic cannabinoids (SCs). The most frequently reported SCs in non-biological samples were 4F-MDMB-BINACA, MDMB-4en-PINACA, and 5F-ADB. These were smuggled mainly through the postal services deposited on paper or herbal matrices. Concentrations of SCs detected on seized paper ranged between 0.05 and 1.17 mg/cm

© 2020 Royal Society of Chemistry. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1039/D0ME00093K.

A novel approach for the identification of New Psychoactive Substances (NPS) by means of Raman spectroscopy coupled with Principal Components Analysis (PCA) employing the largest dataset of NPS reference materials to date is reported here. Fifty three NPS were selected as a structurally diverse subset from an original dataset of 478 NPS compounds. The Raman spectral profiles were experimentally acquired for all 53 substances, evaluated using a number of pre-processing techniques, and used to generate a PCA model. The optimum model system used a relatively narrow spectral range (1300–1750 cm−1) and accounted for 37% of the variance in the dataset using the first three principal components, despite the large structural diversity inherent in the NPS subset. Nonetheless, structurally similar NPS (i.e., the synthetic cannabinoids FDU-PB-22 & NM-2201) grouped together in the PCA model based on their Raman spectral profiles, while NPS with different chemical scaffolds (i.e., the benzodiazepine flubromazolam and the cathinone α-PBT) were well delineated, occupying markedly different areas of the three-dimensional scores plot. Classification of NPS based on their Raman spectra (i.e., chemical scaffolds) using the PCA model was further investigated. NPS that were present in the initial dataset of 478 NPS but were not part of the selected 53 training set (validation set) were observed to be closely aligned to structurally similar NPS within the generated model system in all cases. Furthermore, NPS that were not present in the original dataset of 478 NPS (test set) were also shown to group as expected in the model (i.e., methamphetamine and N-ethylamphetamine). This indicates that, for the first time, a model system can be applied to potential ‘unknown’ psychoactive substances, which are new to the market and absent from existing chemical libraries, to identify key structural features to make a preliminary classification. Consequently, it is anticipated that this study will be of interest to the broad scientific audience working with large structurally diverse chemical datasets and particularly to law enforcement agencies and associated scientific analytical bodies worldwide investigating the development of novel identification methodologies for psychoactive substances.

In this chapter, the use of Raman spectroscopy, a light-based scattering technique, will be examined for its chemical detection of novel psychoactive substances (NPS) in forensic applications. As it is a vibrational technique based on changes in polarisability, Raman spectroscopy has been shown to decipher NPS chemical analogues as well as the NPS from cutting agents and adulterants present in associated products. Analysis can be done in the laboratory or in-field using handheld versions, in which the latter often have in-built matching algorithms for a quick response for non-experts. Analysis can often be carried out through the product packaging (i.e., glass and plastic), however the presence of impurities or cutting agents can lead to high levels of fluorescence which often masks the instrument response from an NPS. Methods for overcoming fluorescence interference includes spectral pre-processing, use of lower energy source radiation, and Surface Enhanced Raman Spectroscopy (SERS). In particular, the availability of handheld Raman spectrometers and the signal enhancements observed for SERS show much potential for application in crime scene investigations.

Purpose – The purpose of this paper is to determine pharmacists’ knowledge of legal highs (novel psychoactive substances (NPS)). Design/methodology/approach – A questionnaire was handed out at two London pharmacist continuing education events in mid-2014. These events update pharmacists about developments of interest/relevance to the profession and to improve their practice. A total of 54 forms were returned; a response rate of 26 percent. Findings – Most pharmacists had poor knowledge of NPS and many considered that NPS were not important to their work, with few having had to advise customers in this area. Despite this, the majority thought that they had insufficient information about NPS. There was a negative correlation between the age of the pharmacist and knowledge of NPS. Research limitations/implications – The sample is a self-selected one drawn from registered pharmacists working in community pharmacies in northwest London, and thus does not include hospital pharmacies. Self-selection means that respondents may only reflect those who are interested in the NPS phenomenon and not the wider pharmacy community. The geographical area covered may not be representative of London as a whole, or indeed other parts of the UK or other EU countries. Practical implications – It is clear that pharmacists do not know much about NPS but would like to know more. This information might improve their practice. Social implications – Pharmacists, easier to see than general practitioners, could be a useful source of information for NPS misusers. Originality/value – There have been no previous attempts to gauge the level of knowledge by pharmacists of legal highs/NPS in the UK or elsewhere to our knowledge.

Straight chain alkanes modified by metal oxide nanoclusters have gained wide recognition in applications in tribology, energy and thermal storage. This paper investigates the system’s rheological properties and diffusion coefficient in a reflection of the nanocluster’s nanofluidic dispersibility and stability in the domain of thermal and diffusive properties. A computational model working on CuO nanoclusters in an alkane (C20H44) fluidic system has been developed at an atomic-molecular level. The simulation results are used to assess the outcomes of the suspension’s fluidic stability and thermal diffusive capabilities. A COMPASS force field was employed, and periodic boundary conditions were defined to address the molecular dynamic (MD) simulation results in the dispersion system. The MD viscosity quantification using stress autocorrelation function shows a monotonic decay for 303–323 K temperatures. These results of autocorrelation calculations were used for validating viscosity results obtained from MD simulation. The viscosity of the CuO-Alkane system was found out to be 1.613 mPa s at 303 K. The diffusion coefficients were also calculated for the CuO-Alkane system using mean square displacement and it was found that at 303 K this system gives 4.302 E−11 m2/s rate of diffusion.

Antibacterial Cu bearing stainless steels (CuSS) have been developed recently and their performance has attracted significant attention widely in biomedical, healthcare and environmental facilities in cross-disciplines. The antibacterial ability and its efficiency of the CuSS are associated to the rate and concentration of Cu2+ ions releases from its surface. The surface properties such as corrosion resistance are also influenced by the amount and the rate of Cu ions released. Thus, the aim of this study focused on the determination of trace release amount of Cu2+ ions from a typical copper bearing 304 stainless steel (304CuSS). Meanwhile, the release of other key elements in the material such as Cr, Fe, Ni were also examined, and found these multiple elemental releases produced a highly synergistic effect on killing bacterium. The release rate of the metals from 304CuSS was conducted by an inductively coupled plasma optical emission spectrometry (ICP-OES). In this study, the commercial 304 stainl...

New psychoactive substances (NPS) can be generally described as a set of compounds that have been designed to mimic the effects of illegal recreational drugs, but are not subject to restriction or control with respect to existing regulations and legislation. In recent years, the number and chemical diversity of emergent NPS has increased substantially, and regulators have struggled to develop methods for accurate detection of NPS at the same rate. Existing approaches to NPS classification are pragmatic and/or semi-systematic and do not lend themselves to objective spectroscopic classification of emergent NPS. As such, this research discusses the identification of a systematic NPS classification based on chemical structures. A set of 478 NPS were grouped according to the similarity between their chemical structural features using hierarchical clustering and a maximum common substructure of 9 atoms, which included both hydrogen and heavy atoms. The rationale for including hydrogen atoms is that accurate spectroscopic identification of NPS will be dependent upon variations in substitution patterns in the molecules. This analysis generated 79 clusters, arising from 21 superclusters. The medoid substances of each cluster were used to form a dataset that was representative of the chemical space encompassed by known NPS. Subsequent categorisation of a test set of NPS showed that the test substances were assigned to an appropriate cluster when the Tanimoto similarity coefficient between the cluster medoid and the test substance was at least 0.5. This indicates that the cluster medoids could be used for assignment of emerging NPS to systematically-defined categories based on chemical structure. These medoids will also aid in the prediction of spectroscopic properties for emergent NPS, which will be invaluable for structure-based classifications and development of methods for detection of emerging NPS.

The chemical identification of new psychoactive substances (NPS) in the field is challenging due not only to the plethora of substances available, but also as a result of the chemical complexity of products and the chemical similarity of NPS analogues. In this study, handheld Raman spectroscopy and the use of two excitation wavelengths, 785 and 1064nm, were evaluated for the identification of 60 NPS products. The products contained a range of NPS from classes including the aminoindanes, arylalkylamines, benzodiazepines, and piperidines & pyrrolidines. Identification was initially assessed using the instruments' in built algorithm (i.e., % HQI) and then further by visual inspection of the Raman spectra. Confirmatory analysis was preformed using gas chromatography mass spectrometry. For the 60 diverse products, an NPS was successfully identified via the algorithm in 11 products (18%) using the 785nm source and 29 products (48%) using the 1064nm source. Evaluation of the Raman spectra showed that increasing the excitation wavelength from 785 to 1064nm improved this 'first pass' identification primarily due to a significant reduction in fluorescence, which increased S/N of the characteristic peaks of the substance identified. True positive correlations between internet products and NPS signatures ranged from 57.0 to 91.3% HQI with typical RSDs

Metal oxide nanoparticles offer great merits over controlling rheological, thermal, chemical and physical properties of solutions. The effectiveness of a nanoparticle to modify the properties of a fluid depends on its diffusive properties with respect to the fluid. In this study, rheological properties of aqueous fluids (i.e. water) were enhanced with the addition of CeO2 nanoparticles. This study was characterized by the outcomes of simulation and experimental results of nanofluids. The movement of nanoparticles in the fluidic media was simulated by a large-scale molecular thermal dynamic program (i.e. LAMMPS). The COMPASS force field was employed with smoothed particle hydrodynamic potential (SPH) and discrete particle dynamics potential (DPD). However, this study develops the understanding of how the rheological properties are affected due to the addition of nanoparticles in a fluid and the way DPD and SPH can be used for accurately estimating the rheological properties with Brownian effect. The rheological results of the simulation were confirmed by the convergence of the stress autocorrelation function, whereas experimental properties were measured using a rheometer. These rheological values of simulation were obtained and agreed within 5 % of the experimental values; they were identified and treated with a number of iterations and experimental tests. The results of the experiment and simulation show that 10 % CeO2 nanoparticles dispersion in water has a viscosity of 2.0–3.3 mPas.

Cathinones are one of the most popular categories of new psychoactive substances (NPS) consumed. Cathinones have different pharmacological activities and receptor selectivity for monoamine transporters based on their chemical structures. They are incorporated into NPS mixtures and used with other NPS or 'traditional' drugs. Cathinone use represents significant health risks to individuals and is a public health burden.Evidence of poly-NPS use with cathinones, seizure information, and literature analyses results on NPS mixtures was systematically gathered from online database sources, including Google Scholar, Scopus, Bluelight, and Drugs-Forum.Results highlight the prevalence of NPS with low purity, incorporation of cathinones into NPS mixtures since 2008, and multiple members of the cathinone family being present in individual UK-seized samples. Cathinones were identified as adulterants in NPS marketed as being pure NPS, drugs of abuse, branded products, herbal blends, and products labelled "not for human consumption." Toxicity resulting from cathinone mixtures is unpredictable because key attributes remain largely unknown. Symptoms of intoxication include neuro-psychological, psychiatric, and metabolic symptoms. Proposed treatment includes holistic approaches involving psychosocial, psychiatric and pharmacological interventions.Raising awareness of NPS, education, and training of health care professionals are paramount in reducing harms related to cathinone use.

Institute of Psychiatry and Neurology (IPIN), Warsaw, PolandObjectives The recent emergence of new psychoactive compounds (novel psychoactive substances (NPS)) has raised prominent challengesin the fields of drug policy, substance use research, public health and service provision. The Recreational Drugs European Network project,funded by the European Commission, was implemented to improve the information stream to young people and professionals about effects/risks of NPS by identifying online products and disseminating relevant information through technological tools.Methods Regular multilingual qualitative assessments of websites, drugs fora and other online resources were carried out using the Googlesearch engine in eight languages from collaborating countries. These included the following: the UK, Norway, Belgium, Germany, Hungary,Poland, Italy and Spain. Products were tested and prevention messages were developed and disseminated via technological tools such asinteractive websites, SMS alert, social networking (Facebook, Twitter), Multimedia (You Tube), Smartphone applications (iPhone) andvirtual learning environments (Second Life).Results The Recreational Drugs European Network project established itself as the first Europe-wide prevention programme designed forNPS based on the efficacy of novel information and communication technology-based forms of intervention. More than 650 NPS productsand combinations were identified; relevant information was disseminated to target population and advice was given to both European Union/international agencies and national policy makers.Conclusions Web-monitoring activities are essential for mapping the diffusion of NPS and the use of technological tools can besuccessfully incorporated in specific prevention programmes. Furthermore, the involvement of multi-disciplinary internationalpartnerships was and continues to be fundamental for responding to such a prominent challenge. Copyright © 2013 John Wiley& Sons, Ltd.key words—new psychoactive compounds; addiction; public health

Objectives A method was developed to analyze St John's wort (Hypericum perforatum L.) herb and preparations using inductively coupled plasma–optical emission spectroscopy (ICP-OES) to determine the quantity of 11 elements (Al, B, Ba, Ca, Cu, Fe, Mg, Mn, Ni, Sr and Zn). Methods This study includes the evaluation of digestion acids and calibration methods, as well as instrumental parameters such as choice of nebulizer and emission wavelength. Key findings Two nebulizers (Conikal and SeaSpray) performed similarly for most elements, and two optimum wavelengths were determined for each element. Five acids were evaluated for the digestion of the Polish Certified Reference Material Tea Leaves (INCT-TL-1), while three were taken forward to use for the different St John's wort formulations (i.e. herb, capsule and tablet). A simple protocol using 5 ml HNO3 was sufficient in most cases; however, variability was observed for elements often bound in silicates (e.g. Al, Fe and Zn). An external weighted calibration was also found to be preferential over unweighted, and the use of standard addition affected some concentration values up to 20%. Conclusions Therefore, this paper presents the development and optimized method parameters to be used with ICP-OES that will allow the analysis of 11 key elements present in St John's wort herb and preparations.

An anthracene molecular probe has been synthesised and shown to target mephedrone, a stimulant drug from the cathinone class of new psychoactive substances (NPS). A protocol has been developed to detect mephedrone via the probe using NMR spectroscopy in a simulated street sample containing two of the most common cutting agents, benzocaine and caffeine.

Objectives The fully synthetic ‘legal high’ 5,6-methylenedioxy-2-aminoindane (MDAI) is an analogue of 3,4-methylenedioxymethamphetamine. Although developed in the 1990s, it was not widely abused until 2010. However, mephedrone was banned in the UK in April 2010, and almost immediately, MDAI was widely advertised as a legal alternative. This paper provides both an overview of the current state of knowledge of MDAI and a critical analysis of online available information relating to its psychoactive effects, adverse reactions and use in combination with other drugs. Methods The literature on MDAI was searched in three databases: PsycInfo, PubMed and MedScape. Once the availability of information on MDAI was identified within these websites, further specific searches were carried out for narratives focusing on the nature of its effects on users, motivations behind its recreational use and possible trends of misuse, and any other relevant information. Results Internet-sourced products have been shown variously to contain mephedrone, and mixed compositions of inorganic substances, while containing no MDAI. Numbers of Internet searches have been considerably higher in the UK compared with Germany and the US. Conclusions Better international collaboration levels may be needed to tackle the novel and fast growing phenomenon of novel psychoactive drug availability from the web. Copyright © 2012 John Wiley & Sons, Ltd.

The metal binding capacities, conditional stability constants, and secondary structure of immobilized polyaspartic acid (PLAsp) (n = 6, 20, and 30) on TentaGel resin were determined when binding Mg2+, Co2+, Cd2+, and Ni2+. Metal binding to the synthesized peptides was evaluated using breakthrough curves from a packed microcolumn and flame atomic absorption spectrophotometry (FAAS) detection. The metal capacities reached values of 590, 2160, and 3710 mumol of metal/g of resin for the 6-mer, 20-mer, and 30-mer, respectively, and this resulted in 2-3 residues per metal for all peptides and metals tested. Surprisingly, the concentrated environment of the resin along with the spatial distribution of attachment groups allowed for most residues to participate in metal binding regardless of the peptide length. Conditional stability constants calculated using single metal binding isotherms indicated that binding strength decreased as the chain length increased on the resin. Raman microscopy on single beads was used to determine PLAsp secondary structure, and all peptides were of a mixed conformation (i.e., beta-sheets, alpha-helices, random chain, etc.) during neutral conditioning and metal binding. Uniquely, the longer 20-mer and 30-mer peptides showed a distinct change from a mixed conformation to beta-sheets and alpha-helices during metal release with acid. This study confirms that metal release by longer immobilized peptides is often assisted by a conformational change, which easily spoils the binding cavity, while shorter peptides may release metal primarily by H+ displacement.

In order to investigate the in vivo dopamine (DA) stimulant properties of selected 3rd generation Spice/K2 cannabinoids, BB-22, 5F-PB-22, 5F-AKB-48 and STS-135, their in vitro affinity and agonist potency at native rat and mice CB1 receptors was studied. The compounds bind with high affinity to CB1 receptors in rat cerebral cortex homogenates and stimulate CB1-induced [(35)S]GTPγS binding with high potency and efficacy. BB-22 and 5F-PB-22 showed the lowest Ki of binding to CB1 receptors (0.11 and 0.13 nM), i.e., 30 and 26 times lower respectively than that of JWH-018 (3.38 nM), and a potency (EC50, 2.9 and 3.7 nM, respectively) and efficacy (Emax, 217% and 203%, respectively) as CB1 agonists higher than JWH-018 (EC50, 20.2 nM; Emax, 163%). 5F-AKB-48 and STS-135 had higher Ki for CB1 binding, higher EC50 and lower Emax as CB1 agonists than BB-22 and 5F-PB-22 but still comparatively more favourable than JWH-018. The agonist properties of all the compounds were abolished or drastically reduced by the CB1 antagonist/inverse agonist AM251 (0.1 μM). No activation of G-protein was observed in CB1-KO mice. BB-22 (0.003-0.01 mg/kg i.v.) increased dialysate DA in the accumbens shell but not in the core or in the medial prefrontal cortex, with a bell shaped dose-response curve and an effect at 0.01 mg/kg and a biphasic time-course. Systemic AM251 (1.0 mg/kg i.p.) completely prevented the stimulant effect of BB-22 on dialysate DA in the NAc shell. All the other compounds increased dialysate DA in the NAc shell at doses consistent with their in vitro affinity for CB1 receptors (5F-PB-22, 0.01 mg/kg; 5F-AKB-48, 0.1 mg/kg; STS-135, 0.15 mg/kg i.v.). 3rd generation cannabinoids can be even more potent and super-high CB1 receptor agonists compared to JWH-018. Future research will try to establish if these properties can explain the high toxicity and lethality associated with these compounds.

The identification of ‘legal highs’ is challenging as they often do not match their label claim and contain a wide range of impurities and/or adulterants. In addition, there is a need for techniques to be on-site, rapid and non-destructive. The feasibility of using the in-built algorithms of handheld near-infrared (NIR), Raman and attenuated total reflectance Fourier transform-infrared (ATR-FT-IR) spectroscopy for the identification of ‘legal high’ substances was investigated. Spectral libraries were constructed using three substances found in ‘legal highs’ (i.e., dextromethorphan, 2-aminoindane and lidocaine) and their 50 : 50 mixtures with caffeine. Model dilution mixtures with caffeine (i.e., 5–95% m/m) and seven ‘legal high’ Internet products were used to test the method. The ‘legal high’ constituents in most of the model mixtures were identified within a minimum range of 30–60% m/m for NIR, 20–75% m/m for Raman, and 41–85% m/m for ATR-FT-IR. This demonstrates that simple library mixtures could be used to identify test substances when the concentrations are variable. Below and above these levels, the test mixtures often correlated to the component in higher concentration. Collectively, the instruments identified the main constituents in the seven Internet products with varying correlation criteria. The NIR and ATR-FT-IR provided complementary information compared to Raman when carbohydrate cutting agents were added to the product, yet the Raman showed a high fluorescence signal for three products hindering identification. These initial studies indicate the suitability of three complementary techniques for rapid identification of ‘legal high’ products. Further development of spectral libraries, algorithms, and use of alternative Raman excitation wavelengths is needed to provide adequate tools for in-field analysis by non-experts.

An electrothermal vaporizer inductively coupled plasma mass spectrometer (ETV-ICPMS) was used to quantitatively screen metals bound to single polystyrene (TentaGel) beads with immobilized oligopeptides. Tests were performed using ETV-ICPMS to screen a series of identical beads as well as a series of combinatorial library beads exposed to a multimetal solution composed of Mg2+, Mn2+, Ni2+, Cu2+, Cd2+, Eu2+, and Pb2+. The residual metal content remaining bound to the beads after acid extractions was also analyzed by solid sampling of the entire bead using oxygen ashing in the ETV. Nine beads (80 mesh, 0.25 mmol g(-1) nominal capacity) containing covalently attached polyaspartic acid (PLAsp; n = 20) showed metal extract concentrations in the range of 4-130 ng mL(-1). After normalizing by bead volume, the precision of capacity measurements in a single bead (7-14%) was primarily dictated by analysis error and contributions from bead diameter measurement with negligible contributions, surprisingly, from variations in site density from bead to bead. A sample combinatorial library of the sequence GXXGXXGXXGXX (X = cysteine, aspartic acid, or glutamic acid and G = glycine) (60 mesh, 0.25 mmol g(-1) nominal capacity) was also used to demonstrate the utility of this method. Metal extract concentrations ranged from 1 to 1300 ng mL(-1) with significant concentration variation between beads, indicating the individual selectivity on each bead. For these larger beads, analysis precision (i.e., capacity precision) was further improved to 3-10% due to the overall increase in bead metal content. Through metal extract determinations, ETV-ICPMS was shown to be a viable nondestructive tool for full metal characterization of "hit" sequences belonging to a combinatorial library.

Short-chain peptides (two and seven residues) consisting of a glycine (Gly) attachment group and various combinations of cysteine (Cys) and/or aspartic acid (Asp) were synthesized by Fmoc solid phase peptide synthesis (SPPS) on Tentagel resin. One selected peptide was synthesized on controlled pore glass (CPG) for comparison. The objective was to evaluate metal binding capacities and selectivities of short-chain peptides when minor alterations in the amino acid sequences were made. Metal binding of Ni2+, Cd2+, Co2+, and Mg2+ to the synthesized peptides was evaluated using breakthrough curves from a packed microcolumn and flame atomic absorption spectrophotometry (FAAS) detection. Peptides composed primarily of Asp showed single metal capacities as large as 720 μmol metal/g Tentagel resin and 130 μmol metal/g CPG. Simultaneous elution of a multi-metal solution demonstrated that peptides possessing only two Cys residues and four Asp residues were sufficient to yield selective binding of Cd2+ over Ni2+ and Co2+ similar to the selectivity of a six-Cys residue chain but with 60% more Cd2+ capacity. Interestingly, peptides supported on Tentagel resin appeared to reach equilibrium with metal-containing influent flow rates of at most 2 ml/min (or a linear velocity of 11 cm/s) and is attributed to better mass transport with the resin than with the CPG. Conditional stability constants calculated for the six-Asp residue chain and each metal showed the majority of sites having a log K in the range of 4.6–4.8. The peptides studied were also able to efficiently preconcentrate solutions containing as little as 0.05 μg/ml Cd2+ or Ni2+ in an artificial seawater matrix. Uniquely, the seven residue peptides showed surprisingly high metal capacities and metal-to-residue binding ratios (reaching ∼1:2), and are an order of magnitude better than results previously obtained for longer chain polyamino acids (50–70 residues) attached to CPG via silane chemistry.

Recently,a significant amount of work has focused on metal binding by natural systems for various applications. This review will focus on the utility of amino acids, short peptides, and proteins that have been immobilized onto solid supports for use in metal binding. These systems include single amino acids, poly-amino acids, and peptides immobilized onto supports such as silica, polymer resins, and membranes. Also included are the studies involving the use of immobilized amino acids in ion-exchange chromatography.

Layer-by-layer deposition of polyelectrolytes on porous supports is a convenient method for producing ultrathin membranes with moderate ion-transport selectivities. This study shows that the capping of poly(styrene sulfonate) (PSS)/poly(allylamine hydrochloride) (PAH) membranes with a few layer pairs of poly(acrylic acid) (PAA)/PAH results in dramatic increases in anion-transport selectivity. Deposition of less than eight total layer pairs yields reliable Cl-/SO42- and Cl-/Fe(CN)63- selectivities up to 150 and 3000, respectively. Field-emission scanning electron microscope images show that the surface structure of PAA/PAH is altered by deposition on PSS/PAH, and we surmise that the PAA/PAH on these hybrid films is less strongly hydrated than the surface of pure PAA/PAH membranes. This would result in a higher surface charge density and more Donnan exclusion of multiply charged ions. Termination of membranes with PAH rather than PAA greatly reduces (in some cases reverses) Cl-/SO42- selectivities, demonstr...

Despite the widespread, and generally very safe, use of aluminium-containing antiperspirants there is a paucity of studies examining, in vitro or in vivo, the percutaneous absorption of aluminium and even fewer that examine this phenomena from consumer formulations. Aluminium has been considered to be a neurotoxicant, with suggestions that it may play a role in brain disorders, including Alzheimer's disease. However, the United Kingdom's Alzhemier's Society currently suggest that, while there might be “circumstantial evidence linking this metal with Alzhemier's disease … no causal relationship has yet been proved”. They further comment that, as evidence for other causes of Alzheimer's disease continues to grow, “a possible link with aluminium seems increasingly unlikely” (Alzheimer's Society, 2013).

Synthesis of high-flux composite membranes requires methods for deposition of ultrathin, defect-free films on highly permeable supports. Layer-by-layer deposition of polyelectrolytes on porous alumina (0.02 μm pore diameter) produces such membranes. Electron microscopy shows that five bilayers (

The fully synthetic 'legal high' 5,6-methylenedioxy-2-aminoindane (MDAI) is an analogue of 3,4-methylenedioxymethamphetamine. Although developed in the 1990s, it was not widely abused until 2010. However, mephedrone was banned in the UK in April 2010, and almost immediately, MDAI was widely advertised as a legal alternative. This paper provides both an overview of the current state of knowledge of MDAI and a critical analysis of online available information relating to its psychoactive effects, adverse reactions and use in combination with other drugs.The literature on MDAI was searched in three databases: PsycInfo, PubMed and MedScape. Once the availability of information on MDAI was identified within these websites, further specific searches were carried out for narratives focusing on the nature of its effects on users, motivations behind its recreational use and possible trends of misuse, and any other relevant information.Internet-sourced products have been shown variously to contain mephedrone, and mixed compositions of inorganic substances, while containing no MDAI. Numbers of Internet searches have been considerably higher in the UK compared with Germany and the US.Better international collaboration levels may be needed to tackle the novel and fast growing phenomenon of novel psychoactive drug availability from the web.

The concept of generic and tunable sensor materials for the detection of proteases based on the thin film degradation of peptide cross-linked dextran hydrogels was explored. Hydrogel cross-links were formed via simple imine linkages between aldehyde groups in oxidized dextran and a peptide sequence susceptible to protease cleavage. Degradation of the hydrogel films was monitored in this study using a quartz crystal microbalance (QCM). The sensor material was developed using the protease/peptide pair of human neutrophil elastase (HNE) and Ala-Ala-Pro-Val-Ala-Ala-Lys (AAPVAAK). A direct relationship between the hydrogel degradation rate and protease activity was observed; HNE activities from 2.5 to 30 U ml−1 were detected using 25% cross-linked films. Film degradation was rapid and was complete in less than 10 min for HNE activities ≥10 U ml−1. An increase in the rate of degradation by a factor of 3.5 was achieved by increasing the cross-linking density from 25% to 75%. QCM admittance data fitted with a BVD equivalent circuit showed increases in film viscoelasticity upon enzyme addition. A second protease/peptide pair of cathepsin G and Ala-Ala-Pro-Phe-Phe-Lys (AAPFFK) was tested where 25% AAPFFK cross-linked hydrogels demonstrated a rapid response at 100 mU ml−1. Swapping the protease/peptide pairs to HNE/AAPFFK and cathepsin G/AAPVAAK showed low levels of cross-sensitivity further demonstrating the specificity of film degradation.