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1.
Drug Test Anal ; 9(5): 734-743, 2017 May.
Article in English | MEDLINE | ID: mdl-27400773

ABSTRACT

Herbal smoking blends containing synthetic cannabinoids have become popular alternatives to marijuana. These products were previously sold in pre-packaged foil bags, but nowadays seizures usually contain synthetic cannabinoid powders together with unprepared plant materials. A question often raised by the Swedish police is how much smoking blend can be prepared from certain amounts of banned substance, in order to establish the severity of the crime. To address this question, information about the synthetic cannabinoid content in both the powder and the prepared herbal blends is necessary. In this work, an extraction procedure compatible with direct NMR quantification of synthetic cannabinoids in herbal smoking blends was developed. Extraction media, time and efficiency were tested for different carrier materials containing representative synthetic cannabinoids. The developed protocol utilizes a 30 min extraction step in d4 -methanol in presence of internal standard allowing direct quantitation of the extract using NMR. The accuracy of the developed method was tested using in-house prepared herbal smoking blends. The results showed deviations less than 0.2% from the actual content, proving that the method is sufficiently accurate for these quantifications. Using this method, ten synthetic cannabinoids present in sixty-three different herbal blends seized by the Swedish police between October 2012 and April 2015 were quantified. Obtained results showed a variation in cannabinoid contents from 1.5% (w/w) for mixtures containing MDMB-CHMICA to over 5% (w/w) for mixtures containing 5F-AKB-48. This is important information for forensic experts when making theoretical calculations of production quantities in legal cases regarding "home-made" herbal smoking blends. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Adamantane/analogs & derivatives , Cannabinoids/analysis , Illicit Drugs/analysis , Indazoles/analysis , Indoles/analysis , Magnetic Resonance Spectroscopy/methods , Plant Preparations/analysis , Adamantane/analysis , Humans , Methanol/chemistry , Smoking, Non-Tobacco Products/epidemiology , Solvents/chemistry , Sweden/epidemiology
2.
Biomater Sci ; 3(8): 1208-17, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26222036

ABSTRACT

Heparin-imprinted synthetic polymer surfaces with the ability to attenuate activation of both the complement and the coagulation system in whole blood were successfully produced. Imprinting was achieved using a template coated with heparin, a highly sulfated glycosaminoglycan known for its anticoagulant properties. The N,N'-diacryloylpiperazine-methacrylic acid copolymers were characterized using goniometry, AFM and XPS. The influence of the molecular imprinting process on morphology and template rebinding was demonstrated by radioligand binding assays. Surface hemocompatibility was evaluated using human whole blood without anticoagulants followed by measurement of complement activation markers C3a and sC5b-9 and platelet consumption as a surrogate coagulation activation marker. The observed low thrombogenicity of this copolymer combined with the attenuation of complement activation induced by the molecular imprint offer potential for the development of self-regulating surfaces with important potential clinical applications. We propose a mechanism for the observed phenomena based upon the recruitment of endogenous sulfated glycosaminoglycans with heparin-like activities.


Subject(s)
Anticoagulants/chemistry , Complement Membrane Attack Complex/chemistry , Glycosaminoglycans/chemistry , Heparin/chemistry , Methacrylates/chemistry , Piperazines/chemistry , Polymers/chemistry , Anticoagulants/metabolism , Blood Coagulation , Complement Activation , Complement Membrane Attack Complex/metabolism , Glycosaminoglycans/metabolism , Humans , Platelet Count , Surface Properties
3.
Biomaterials ; 36: 55-65, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25292422

ABSTRACT

Inappropriate complement activation is often responsible for incompatibility reactions that occur when biomaterials are used. Complement activation is therefore a criterion included in legislation regarding biomaterials testing. However, no consensus is yet available regarding appropriate complement-activation-related test parameters. We examined protein adsorption in plasma and complement activation/cytokine release in whole blood incubated with well-characterized polymers. Strong correlations were found between the ratio of C4 to its inhibitor C4BP and generation of 10 (mainly pro-inflammatory) cytokines, including IL-17, IFN-γ, and IL-6. The levels of complement activation products correlated weakly (C3a) or not at all (C5a, sC5b-9), confirming their poor predictive values. We have demonstrated a direct correlation between downstream biological effects and the proteins initially adhering to an artificial surface after contact with blood. Consequently, we propose the C4/C4BP ratio as a robust, predictor of biocompatibility with superior specificity and sensitivity over the current gold standard.


Subject(s)
Biocompatible Materials/adverse effects , Complement Activation/drug effects , Inflammation/blood , Inflammation/chemically induced , Polymers/adverse effects , Complement C4b-Binding Protein/immunology , Complement Membrane Attack Complex/immunology , Complement System Proteins/immunology , Humans , Inflammation/immunology , Interferon-gamma/immunology , Interleukin-17/blood , Interleukin-17/immunology , Interleukin-6/blood , Interleukin-6/immunology
4.
J Biomed Mater Res A ; 97(1): 74-84, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21319295

ABSTRACT

The aim of this study was to create polymeric materials with known properties to study the preconditions for complement activation. Initially, 22 polymers were screened for complement activating capacity. Based on these results, six polymers (P1-P6) were characterized regarding physico-chemical parameters, for example, composition, surface area, pore size, and protein adsorption from human EDTA-plasma. P2, P4, and reference particles of polystyrene and polyvinyl chloride, were hydrophobic, bound low levels of protein and were poor complement activators. Their accessible surface was limited to protein adsorption in that they had pore diameters smaller than most plasma proteins. P1 and P3 were negatively charged and adsorbed IgG and C1q. A 10-fold difference in complement activation was attributed to the fact that P3 but not P1 bound high amounts of C1-inhibitor. The hydrophobic P5 and P6 were low complement activators. They selectively bound apolipoproteins AI and AIV (and vitronectin), which probably limited the binding of complement activators to the surface. We demonstrate the usefulness of the modus operandi to use a high-throughput procedure to synthesize a great number of novel substances, assay their physico-chemical properties with the aim to study the relationship between the initial protein coat on a surface and subsequent biological events. Data obtained from the six polymers characterized here, suggest that a complement-resistant surface should be hydrophobic, uncharged, and have a small available surface, accomplished by nanostructured topography. Additional attenuation of complement can be achieved by selective enrichment of inert proteins and inhibitors.


Subject(s)
Blood Proteins/chemistry , Complement System Proteins/metabolism , Materials Testing/methods , Polymers/chemistry , Adsorption , Blotting, Western , Complement Activation , Cross-Linking Reagents/chemistry , Electrophoresis, Polyacrylamide Gel , Endotoxins/metabolism , Flow Cytometry , Hirudins/metabolism , Humans , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Porosity
5.
Langmuir ; 22(17): 7302-12, 2006 Aug 15.
Article in English | MEDLINE | ID: mdl-16893230

ABSTRACT

We have previously described the efficient guidance and unidirectional sliding of actin filaments along nanosized tracks with adsorbed heavy meromyosin (HMM; myosin II motor fragment). In those experiments, the tracks were functionalized with trimethylchlorosilane (TMCS) by chemical vapor deposition (CVD) and surrounded by hydrophilic areas. Here we first show, using in vitro motility assays on nonpatterned and micropatterned surfaces, that the quality of HMM function on CVD-TMCS is equivalent to that on standard nitrocellulose substrates. We further examine the influences of physical properties of different surfaces (glass, SiO(2), and TMCS) and chemical properties of the buffer solution on motility. With the presence of methylcellulose in the assay solution, there was HMM-induced actin filament sliding on both glass/SiO(2) and on TMCS, but the velocity was higher on TMCS. This difference in velocity increased with decreasing contact angles of the glass and SiO(2) surfaces in the range of 20-67 degrees (advancing contact angles for water droplets). The corresponding contact angle of CVD-TMCS was 81 degrees. In the absence of methylcellulose, there was high-quality motility on TMCS but no motility on glass/SiO(2). This observation was independent of the contact angle of the glass/SiO(2) surfaces and of HMM incubation concentrations (30-150 microg mL(-)(1)) and ionic strengths of the assay solution (20-50 mM). Complete motility selectivity between TMCS and SiO(2) was observed for both nonpatterned and for micro- and nanopatterned surfaces. Spectrophotometric analysis of HMM depletion during incubation, K/EDTA ATPase measurements, and total internal reflection fluorescence spectroscopy of HMM binding showed only minor differences in HMM surface densities between TMCS and SiO(2)/glass. Thus, the motility contrast between the two surface chemistries seems to be attributable to different modes of HMM binding with the hindrance of actin binding on SiO(2)/glass.


Subject(s)
Actomyosin/physiology , Molecular Motor Proteins/physiology , Silicon Dioxide/chemistry , Trimethylsilyl Compounds/chemistry , Collodion/chemistry , Nanotechnology/methods , Surface Properties
6.
J Org Chem ; 71(13): 4845-53, 2006 Jun 23.
Article in English | MEDLINE | ID: mdl-16776512

ABSTRACT

[structures: see text] A class II aldolase-mimicking synthetic polymer was prepared by the molecular imprinting of a complex of cobalt (II) ion and either (1S,3S,4S)-3-benzoyl-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one (4a) or (1R,3R,4R)-3-benzoyl-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one (4b) in a 4-vinylpyridine-styrene-divinylbenzene copolymer. Evidence for the formation of interactions between the functional monomer and the template was obtained from NMR and VIS titration studies. The polymers imprinted with the template demonstrated enantioselective recognition of the corresponding template structure, and induced a 55-fold enhancement of the rate of reaction of camphor (1) with benzaldehyde (2), relative to the solution reactions, and were also compared to reactions with a series of reference polymers. Substrate chirality was observed to influence reaction rate, and the reaction could be competitively inhibited by dibenzoylmethane (6). Collectively, the results presented provide the first example of the use of enantioselective molecularly imprinted polymers for the catalysis of carbon-carbon bond formation.


Subject(s)
Aldehyde-Lyases/chemistry , Aldehyde-Lyases/classification , Benzaldehydes/chemistry , Camphor/chemistry , Ketones/chemical synthesis , Polymers/chemistry , Aldehyde-Lyases/antagonists & inhibitors , Catalysis , Chalcones/chemistry , Chalcones/pharmacology , Cobalt/chemistry , Ketones/chemistry , Kinetics , Ligands , Molecular Structure , Organometallic Compounds/chemistry , Polymers/chemical synthesis , Stereoisomerism , Time Factors
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