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International audience; European “Technical Recommendations” have proposed, with the use of substance concentrations, the use of a pH (≤2 or ≥11.5) to classify waste for the hazard properties HP4 ‘Irritant’ and HP8 ‘Corrosive’. The document add unfortunately that the buffer capacity must be “not low” to classify as hazardous. Buffer capacity refers to a 2018 UK classification guide referring to the ‘corrosive’ level of a method proposed in 1988 for substances and preparations but not retained in EU regulations, but well in its Guidance. The product method uses the pH unclearly associated or not to a 1% concentration. The different methods of classifying products and wastes in terms of corrosivity or irritation are expressed as acid/base concentration and compared. The “corrosive” level of 1988 corresponds to an average strong acid/base concentration ≥14.4%, i.e. 14 times less severe than CLP (acid/base concentration ≥0.44-0.15% for pH only or ≥1% for pH and concentration). The “pH only” method corresponds to the lowest concentration of acid/base and is the most severe. These methods were applied to five hazardous alkaline wastes (pH ≥11.5). The “pH only” method is the only that classifies all waste in accordance with the European List of Waste. To avoid innovation and divergence between products and waste, it seems preferable to use the product regulations “pH only” or eventually “pH and concentration” for HP4 and HP8. Fortunately, the elimination of the danger HP 4 and HP 8 from acidic or alkaline waste can be obtained by neutralization, including for alkaline wastes with CO2.

Objectives In 2009, the Japan Society of Clinical Chemistry (JSCC) recommended a reference method for the measurement of serum high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels. This automated method uses cholesterol esterase-cholesterol dehydrogenase to measure cholesterol levels in fractions obtained after ultracentrifugation and dextran sulfate/magnesium chloride precipitation. In the present study, using fresh samples, we compared the LDL-C and HDL-C levels measured using this method with those measured using the traditional Centers for Disease Control and Prevention (CDC)-beta-quantification (BQ) method. Design and methods: Using both the JSCC and CDC-BQ methods, LDL-C/HDL-C levels were measured in 47 non-diseased and 126 diseased subjects, whose triglyceride levels were lower than 11.29 ​mmol/L (1000 ​mg/dL). Results For LDL-C, the equation of the line representing the correlation between the two methods was y ​= ​0.991x + 0.009 ​mmol/L; r ​= ​0.999; and Sy/x ​= ​0.025 ​mmol/L, where x is the mean LDL-C level measured using the CDC-BQ method. Similarly, for HDL-C, the equation of the line representing the correlation between the two methods was y ​= ​0.988x + 0.041 ​mmol/L, r ​= ​0.999, and Sy/x ​= ​0.019 ​mmol/L, where x is the mean HDL-C level measured using the CDC-BQ method. Conclusions The JSCC method agreed with the CDC-BQ method in cases of both non-diseased and diseased subjects, including those with dyslipidemia., Highlights • Using both the JSCC and BQ methods, LDL-C/HDL-C levels were measured. • The JSCC method agrees with the BQ method. • The JSCC reference method is an accurate, simple, and automatable method. • The JSCC method is suitable for quantitative analysis of LDL-C and HDL-C levels.

Background Aspirin, a commonly used antiplatelet agent, blocks platelet thromboxane A 2 (TXA 2 ) formation from arachidonic acid (AA) by acetylating platelet cyclooxygenase-1 (COX-1). Laboratory methods currently used to detect this antiplatelet effect of aspirin provide variable results. We have reported three methods that assess platelet COX-1 acetylation (inactivation) by aspirin and its direct consequences. The first and second assays use monoclonal anti-human-COX-1 antibodies that only detect acetylated (inactivated) COX-1 and active (non-acetylated) COX-1, respectively. The third method measures platelet production of TXB 2 (the stable metabolite of TXA 2 ) in vitro in response to AA. We compared the results of these three reference methods with other routinely used methods for assessing the functional consequences aspirin treatment. Methods 108 healthy volunteers were treated with low-dose aspirin for 7days. On day 7 following aspirin treatment COX-1 in the platelets was fully acetylated whereas only non-acetylated COX-1 was present in the day 0 platelets. Further, TXB 2 production by day 7 platelets was completely blocked. The following tests were performed on the samples obtained from study participants before and after seven days of aspirin treatment: PFA-100 closure time with collagen/epinephrine cartridge, VerifyNow® (VN) Aspirin Assay, platelet aggregation and ATP secretion using AA, ADP, epinephrine and collagen as agonists. Results Comparing the pre-treatment and day 7 values, methods that use AA as platelet agonist (AA-induced platelet aggregation/secretion and VN Aspirin Assay) showed high discriminative power. In contrast, results of the other tests showed considerable overlap between day 7 and day 0 values. Conclusions Only assays that clearly distinguish between acetylated and non-acetylated platelet COX-1 are useful for establishing the antiplatelet effect of aspirin. The other tests are not suitable for this purpose.

The milk analyse result reliability is important for assurance of foodstuff chain quality. There are more direct and indirect methods for milk composition measurement (fat (F), protein (P), lactose (L) and solids non fat (SNF) content). The goal was to evaluate some reference and routine milk analytical procedures on result basis. The direct reference analyses were: F, fat content (Röse–Gottlieb method); P, crude protein content (Kjeldahl method); L, lactose (monohydrate, polarimetric method); SNF, solids non fat (gravimetric method). F, P, L and SNF were determined also by various indirect methods: – MIR (infrared (IR) technology with optical filters), 7 instruments in 4 labs; – MIR–FT (IR spectroscopy with Fourier’s transformations), 10 in 6; – ultrasonic method (UM), 3 in 1; – analysis by the blue and red box (BRB), 1 v 1. There were used 10 reference milk samples. Coefficient of determination (R2), correlation coefficient (r) and standard deviation of the mean of individual differences (MDsd, for n) were evaluated. All correlations (r; for all indirect and alternative methods and all milk components) were significant (P ≤ 0.001). MIR and MIR–FT (conventional) methods explained considerably higher proportion of the variability in reference results than the UM and BRB methods (alternative). All r average values (x minus 1.64 × sd for 95% confidence interval) can be used as standards for calibration quality evaluation (MIR, MIR–FT, UM and BRB): – for F 0.997, 0.997, 0.99 and 0.995; – for P 0.986, 0.981, 0.828 and 0.864; – for L 0.968, 0.871, 0.705 and 0.761; – for SNF 0.992, 0.993, 0.911 and 0.872. Similarly ​MDsd (x plus 1.64 × sd): – for F 0.071, 0.068, 0.132 and 0.101%; – for P 0.051, 0.054, 0.202 and 0.14%; – for L 0.037, 0.074, 0.113 and 0.11%; – for SNF 0.052, 0.068, 0.141 and 0.204.

Two analytical approaches for the rapid measurement of hydrogen sulfide (H(2)S) have been compared to a reference method for their potential application as a rapid procedure for the quantification of H(2)S formed during alcoholic fermentations. In one case, silver nitrate, lead acetate, and mercuric chloride selective detector tubes for the analysis of H(2)S in air were investigated. In the other case, a commercially available kit for the diagnosis of nitrogen starvation in wine fermentations, which is based on the detection of H(2)S, was investigated. Both methods exhibited excellent linearity of response, but the mercuric chloride tube was found to suffer from interferences due to the concomitant presence of mercaptans, which resulted in erroneous H(2)S quantification. A comparative study between the two methods studied and the cadmium hydroxide/methylene blue reference method commonly used to monitor H(2)S indicate that the two new methods displayed better recoveries at low H(2)S concentrations, besides being more rapid and economical. The two new methods were successfully used to quantify production of H(2)S in different grape juice fermentations. The suitability of each method for the study of specific aspects of H(2)S production during fermentation is discussed.

Casein measurement is important for cheesemaking and control of dairy cow nutrition. Reference Kjeldahl method is not suitable for routine purposes. Infra-red spectroscopy MIR and MIR-FT use can be a solutin. However, their casein specifity is relatively limited. Aim of the work was to assess the quality of performed calibrations for validation of calibration parameters. A retrospective analysis of MIR and MIR-FT calibrations was performed for estimation of limits their suitable parameters. Mean casein values of reference sample sets varied from 2.49 to 2.7% (2.61 ± 0.155). Mean variation range was 0.561 ± 0.164%. The mean correlation coefficient of calibration (KKK) was 0.974 ± 0.018 (P < 0.001). The mean standard deviation of mean for individual differences (SDID) was 0.03 ± 0.011% (from 0.01 to 0.08). MIR-FT results were slightly better both for calibration and for proficiency testing. The high and low KKKs were higher in the case of accepted calibration as in proficiency testing for MIR-FT and MIR (0.986 > 0.964 and 0.970 > 0.948; 0.982 > 0.947 and 0.947 > 0.911; P < 0.001). The casein number varied from 79.4 to 80.56% in bulk milk samples in three years, its variability was low from 1.4 to 1.5% relatively, which shows on relatively reliable casein analyses by methods MIR and MIR-FT. It does not need to agree fuly for individual milk samples. It is linked more to MIR than MIR-FT. Limits for acceptable calibration parameters were derived: > 0.945 for KKK; 0.048 for SDID and 0.029% for mean difference as maximum.

Correlation between the antioxidant capacity and silver nanoparticle formation rates of pomegranate (Punica granatum), quince (Cydonia oblonga), chestnut (Castanea sativa), fig (Ficus carica), walnut (Juglans cinerea), black mulberry (Morus nigra), and white mulberry (Morus alba) leaf extracts is investigated at a fixed illumination. Silver nanoparticles formed in all plant leaf extracts possess round shapes with average particle size of 15 to 25 nm, whereas corresponding surface plasmon resonance peak wavelengths vary between 422 nm and 451 nm. Cupric reducing antioxidant capacity technique is used as a reference method to determine total antioxidant capacity of the plant leaf extracts. Integrated absorbance over the plasmon resonance peaks exhibits better linear relation with antioxidant capacities of various plant leaf extracts compared to peak absorbance values, with correlation coefficient values of 0.9333 and 0.7221, respectively.

[EN] Non-structural carbohydrates (NSC) in plant tissue are frequently quantified to make inferences about plant responses to environmental conditions. Laboratories publishing estimates of NSC of woody plants use many different methods to evaluate NSC. We asked whether NSC estimates in the recent literature could be quantitatively compared among studies. We also asked whether any differences among laboratories were related to the extraction and quantification methods used to determine starch and sugar concentrations. These questions were addressed by sending sub-samples collected from five woody plant tissues, which varied in NSC content and chemical composition, to 29 laboratories. Each laboratory analyzed the samples with their laboratory-specific protocols, based on recent publications, to determine concentrations of soluble sugars, starch and their sum, total NSC. Laboratory estimates differed substantially for all samples. For example, estimates for Eucalyptus globulus leaves (EGL) varied from 23 to 116 (mean = 56) mg g(-1) for soluble sugars, 6-533 (mean = 94) mg g-1 for starch and 53-649 (mean = 153) mg g-1 for total NSC. Mixed model analysis of variance showed that much of the variability among laboratories was unrelated to the categories we used for extraction and quantification methods (method category R-2 = 0.05-0.12 for soluble sugars, 0.10-0.33 for starch and 0.01-0.09 for total NSC). For EGL, the difference between the highest and lowest least squares means for categories in the mixed model analysis was 33 mg g-1 for total NSC, compared with the range of laboratory estimates of 596 mg g-1. Laboratories were reasonably consistent in their ranks of estimates among tissues for starch (r = 0.41-0.91), but less so for total NSC (r = 0.45-0.84) and soluble sugars (r = 0.11-0.83). Our results show that NSC estimates for woody plant tissues cannot be compared among laboratories. The relative changes in NSC between treatments measured within a laboratory may be comparable within and between laboratories, especially for starch. To obtain comparable NSC estimates, we suggest that users can either adopt the reference method given in this publication, or report estimates for a portion of samples using the reference method, and report estimates for a standard reference material. Researchers interested in NSC estimates should work to identify and adopt standard methods., M.G.R. was funded by McMaster fellowship (1158.C). S.P. was funded by Juan de la Cierva contract (MCI project) and project ARBALMONT/786-2012 (OPAN, MAAMA, Spain). F.P. was funded by Fondecyt 11121175. U.N. and M.T. were funded by the Estonian Ministry of Education and Science, grant IUT-8-3. N.G.M. and L.T.D. were funded by DOE-BER. H.D.A. was funded by LANL-LDRD. J.M.-V. was funded by the Spanish Government (CGL 2010-16376). S.H. was funded by the Montana Institute on Ecosystems' Graduate Enhancement Award from NSF EPSCoR Track-1 NSF-IIA-1443108. Valuable comments from Dr Mauricio Mencuccini (University of Edinburgh), Dan Binkley (Colorado State University) and two anonymous reviewers were also greatly appreciated.

WOS: 000281326600009, PubMed ID: 20605749, In situ synthesis of poly(ethylene glycol) (PEG) hydrogels containing gold nanoparticles (AuNPs) and glucose oxidase (GOx) enzyme by photo-induced electron transfer process was reported here and applied in electrochemical glucose biosensing as the model system. Newly designed bionanocomposite matrix by simple one-step fabrication offered a good contact between the active site of the enzyme and AuNPs inside the network that caused the promotion in the electron transfer properties that was evidenced by cyclic voltammetry as well as higher amperometric biosensing responses in comparing with response signals obtained from the matrix without AuNPs. As well as some parameters important in the optimization studies such as optimum pH, enzyme loading and AuNP amount, the analytical characteristics of the biosensor (AuNP/GOx) were examined by the monitoring of chronoamperometric response due to the oxygen consumption through the enzymatic reaction at -0.7 V under optimized conditions at sodium acetate buffer (50 mM, pH 4.0) and the linear graph was obtained in the range of 0.1-1.0 mM glucose. The detection limit (LOD) of the biosensor was calculated as 0.06 mM by using the signal to noise ratio of 3. Moreover, the presence of AuNPs was visualized by TEM. Finally, the biosensor was applied for glucose analysis for some beverages and obtained data were compared with HPLC as the reference method to test the possible matrix effect due to the nature of the samples. (C) 2010 Elsevier B.V. All rights reserved., Istanbul Technical University (ITU)Istanbul Technical University; Ege UniversityEge University; TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); UNAM-Institute of Materials Science and Nanotechnology through the National Nanotechnology Research CenterIhsan Dogramaci Bilkent University, This work was supported by Istanbul Technical University (ITU) and the Ege University Research Grants. M. U. Kahveci thanks to TUBITAK for financial support as a graduate scholarship. Prof. N. Ertas is acknowledged for the fruitful discussions on the electrochemical data. The State Planning Organization of Turkey (DPT) is acknowledged for the support of UNAM-Institute of Materials Science and Nanotechnology through the National Nanotechnology Research Center Project. H. Deniz and M. Guler are also acknowledged for helping TEM imaging and sample preparation for TEM, respectively.