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1.
Anal Chem ; 89(3): 1697-1703, 2017 02 07.
Article in English | MEDLINE | ID: mdl-28208249

ABSTRACT

In this work we present a full-passive flexible multigas sensing tag for the determination of oxygen, carbon dioxide, ammonia, and relative humidity readable by a smartphone. This tag is based on near field communication (NFC) technology for energy harvesting and data transmission to a smartphone. The gas sensors show an optic response that is read through high-resolution digital color detectors. A white LED is used as the common optical excitation source for all the sensors. Only a reduced electronics with very low power consumption is required for the reading of the optical responses and data transmission to a remote user. An application for the Android operating system has been developed for the power supplying and data reception from the tag. The responses of the sensors have been calibrated and fitted to simple functions, allowing a fast prediction of the gases concentration. Cross-sensitivity has also been evaluated, finding that in most of the cases it is negligible or easily correctable using the rest of the readings. The election of the target gases has been due to their importance in the monitoring of modified atmosphere packaging. The resolutions and limits of detection measured are suitable for such kinds of applications.

2.
J Nutr Health Aging ; 21(1): 92-104, 2017.
Article in English | MEDLINE | ID: mdl-27999855

ABSTRACT

The Strategic Implementation Plan of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) proposed six Action Groups. After almost three years of activity, many achievements have been obtained through commitments or collaborative work of the Action Groups. However, they have often worked in silos and, consequently, synergies between Action Groups have been proposed to strengthen the triple win of the EIP on AHA. The paper presents the methodology and current status of the Task Force on EIP on AHA synergies. Synergies are in line with the Action Groups' new Renovated Action Plan (2016-2018) to ensure that their future objectives are coherent and fully connected. The outcomes and impact of synergies are using the Monitoring and Assessment Framework for the EIP on AHA (MAFEIP). Eight proposals for synergies have been approved by the Task Force: Five cross-cutting synergies which can be used for all current and future synergies as they consider overarching domains (appropriate polypharmacy, citizen empowerment, teaching and coaching on AHA, deployment of synergies to EU regions, Responsible Research and Innovation), and three cross-cutting synergies focussing on current Action Group activities (falls, frailty, integrated care and chronic respiratory diseases).


Subject(s)
Aging , Health Behavior , White People , Accidental Falls/prevention & control , Aged , Aged, 80 and over , Chronic Disease , Cooperative Behavior , Europe , Frail Elderly , Humans , Multiple Chronic Conditions , Organizational Innovation , Polypharmacy , Surveys and Questionnaires
3.
Anal Chim Acta ; 694(1-2): 128-35, 2011 May 23.
Article in English | MEDLINE | ID: mdl-21565313

ABSTRACT

A disposable optical tongue for the alkaline ions Na(I) and K(I) is described. The two-sensor layout prepared on a transparent support consists of non-specific polymeric membranes working by ionophore-chromoionophore chemistry. The non-specific behavior of the membranes was controlled by means of the crown ether-type ionophore present. The imaging of the tongue, after reaction for 3 min with the unknown solution, by means of a conventional flatbed scanner working by transmission mode, makes it possible to calculate the H (hue) value of the hue, saturation, value (HSV) color space used as a robust and precise analytical parameter. The modelling of the response of the two-sensor tongue as a sigmoidal surface is used to characterize the behavior of the tongue and as a basis to infer the concentration values. To compute the concentration of two analytes from the two hue values obtained using the optical tongue, a surface fit approach was used. The tongue works over a wide dynamic range (1.0×10(-4)-0.1 M both in Na(I) and K(I)). The sensing membranes show good intramembrane (1.4% RSD) and intermembrane precision (0.71% RSD) and lifetime (around 45 days in darkness). The procedure was used to analyze Na(I) and K(I) in different types of natural waters (tap and mineral), validating the results against a reference procedure.

4.
Anal Chim Acta ; 681(1-2): 71-81, 2010 Nov 29.
Article in English | MEDLINE | ID: mdl-21035605

ABSTRACT

A new colour-based disposable sensor array for a full pH range (0-14) is described. The pH sensing elements are a set of different pH indicators immobilized in plasticized polymeric membranes working by ion-exchange or co-extraction. The colour changes of the 11 elements of the optical array are obtained from a commercial scanner using the hue or H component of the hue, saturation, value (HSV) colour space, which provides a robust and precise parameter, as the analytical parameter. Three different approaches for pH prediction from the hue H of the array of sensing elements previously equilibrated with an unknown solution were studied: Linear model, Sigmoid competition model and Sigmoid surface model providing mean square errors (MSE) of 0.1115, 0.0751 and 0.2663, respectively, in the full-range studied (0-14). The performance of the optical disposable sensor was tested for pH measurement, validating the results against a potentiometric reference procedure. The proposed method is quick, inexpensive, selective and sensitive and produces results similar to other more complex optical approaches for broad pH sensing.

5.
Anal Chem ; 82(2): 531-42, 2010 Jan 15.
Article in English | MEDLINE | ID: mdl-20000770

ABSTRACT

The hue or H component of the hue, saturation, value (HSV) color space has been studied as a quantitative analytical parameter for bitonal optical sensors. The robust nature of this parameter provides superior precision for the measurement of sensors which change colors with the speciation of some indicator molecule. This parameter has been compared to red, green, blue (RGB) intensity and RGB absorbance along with differences and ratios of both intensity and absorbance and has been demonstrated to be 2 to 3 times superior. The H value maintains this superior precision with variations in indicator concentration, membrane thickness, detector spectral responsivity, and illumination. Because this parameter is stable, simple to calculate, easily obtained from commercial devices such as scanners and digital cameras, continuous over the entire color gamut, and bound between values of 0 and 1, it shows great promise for use in a variety of sensing applications including imaging, automated analysis, pharmaceutical sensing, lab-on-a-chip devices, and quality control applications.

6.
J Anim Breed Genet ; 126(6): 463-7, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19912420

ABSTRACT

Bovine spongiform encephalopathy (BSE) is a fatal disease caused by miss folded prion protein. Studies in the cattle, comparing genetic data from BSE diseased and healthy animals have shown that indel polymorphisms in the promoter and intron 1 of PRNP gene were associated with disease susceptibility. Several studies were conducted to find out allele and genotypic frequencies of indel polymorphisms in promoter and intron 1 of the cattle PRNP gene. Unlike domestic cattle and bison, no indel polymorphisms of the PRNP promoter and intron 1 were examined in any population of the water buffalo (Bubalus bubalis). Aim of this study was to analyse frequencies of allele, genotype, and haplotype of the indel polymorphisms (23 bp indel in promoter and 12 bp indel in intron 1) in prion protein coding gene (PRNP) of water buffalo. Therefore a PCR based procedure, previously used in cattle to detect indel polymorphisms of PRNP promoter and intron 1 locus, was applied to 106 Anatolian water buffalo DNAs. Our results have revealed high frequency of in variants and in23/in12 haplotype for PRNP promoter and intron 1 indel polymorphisms in water buffalo. The results of the study have demonstrated that frequencies of allele, genotype, and haplotype of the indel polymorphisms in PRNP gene of the Anatolian water buffalo are significantly different those from cattle and bison PRNP indel polymorphisms.


Subject(s)
Buffaloes/genetics , INDEL Mutation , Prions/genetics , Promoter Regions, Genetic/genetics , Animals , Female , Introns , Male , Polymorphism, Genetic , Turkey
7.
Talanta ; 78(4-5): 1484-8, 2009 Jun 15.
Article in English | MEDLINE | ID: mdl-19362220

ABSTRACT

This paper presents the characterization of optical sensing membranes for calcium based on ionophore-chromoionophore chemistry. Six different ionophores, 18-membered crown ether derivatives, were studied, coming from 18-crown-6 ether and 4,13-diaza-18-crown-6 ether to a series of double-armed crown ethers with different type of terminal groups. The study of optical membranes containing the same transducer and plasticizer allow drawing some conclusions on the influence of lipophilicity and size of the terminal group of the side chain on calcium selectivity. We have calculated the exchange constant K(ILp)exch for each equilibrium with alkaline and alkaline-earth ions and the selectivity coefficient k(Osel)I,J for each ion against calcium as a way for a full characterization of sensing membranes. In all cases the ion:ionophore stability constants for calcium were the highest and the ionophore V containing an (N-adamantylcarbamoyl) acetyl moiety originated the most selective membrane for calcium. Analytical parameters for calcium determination using prepared membranes were calculated.


Subject(s)
Calcium/analysis , Crown Ethers/chemistry , Ionophores/chemistry , Binding Sites , Equipment Design , Membranes, Artificial , Structure-Activity Relationship
8.
J Pharm Biomed Anal ; 23(5): 837-44, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11022909

ABSTRACT

A partial least-squares calibration (PLS) method for the simultaneous spectrofluorimetric determination of salicylic acid (SA), codeine (CO) and pyridoxine (PY) is proposed. The determination of SA, CO, and PY has been carried out in mixtures of up to three components by recording the emission fluorescence spectra between 300 and 500 nm (lambda(exc) = 220 nm). Due to the fact of the strong spectral overlap among the excitation and also among the emission spectra of these compounds, a previous separation should be carried out in order to determine them by conventional spectrofluorimetric methodologies. Here, a full-spectrum multivariate calibration PLS method is developed. The experimental calibration matrix was constructed with 14 samples. The concentration ranges considered were 0.1-2.0 (SA), 0.25-3.0 (CO) and 0.10-2.0 (PY) mg x l(-1). The optimum number of factors was selected by using the cross-validation method. The method also allows the simultaneous determination of acetylsalicylic acid (ASA), CO and PY by previous alkaline hydrolysis of ASA to SA. To check the accuracy of the proposed method, it was applied to the determination of these compounds in synthetic mixtures and in pharmaceuticals.


Subject(s)
Analgesics, Opioid/analysis , Anti-Inflammatory Agents, Non-Steroidal/analysis , Aspirin/analysis , Codeine/analysis , Pyridoxine/analysis , Analysis of Variance , Calibration , Capsules , Drug Combinations , Indicators and Reagents , Least-Squares Analysis , Reproducibility of Results , Software , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Tablets
9.
Talanta ; 43(9): 1457-63, 1996 Sep.
Article in English | MEDLINE | ID: mdl-18966624

ABSTRACT

A method for the simultaneous determination of quinoline yellow (QY) and brilliant blue FCF (BB) in mixtures by solid-phase spectrophotometry has been developed. Both colorants were isolated in Sephadex DEAE A-25 gel showing maximum absorbances at 632 nm and 415 nm for BB and QY respectively. The applicable concentration ranges were between 25.0 and 500.0 mug 1(-1) for BB and between 50.0 and 750.0 mug 1(-1) for QY. The detection limits were 6.1 and 13.4 mug (-1) for BB and QY respectively. Application of the method to real samples (colognes, after shave lotions and shampoo gels) involves a previous extraction process of the colorants before their isolation on the gel.

10.
J Pharm Biomed Anal ; 9(2): 117-22, 1991.
Article in English | MEDLINE | ID: mdl-1873303

ABSTRACT

Third-order and fourth-order derivative spectra have been used for determining sulphathiazole, sulphanilamide and their binary mixtures. The method is suitable for 1-22 micrograms ml-1 of sulphathiazole and for 0.5-14 micrograms ml-1 of sulphanilamide and can be applied for determining the sulphonamides in pharmaceuticals.


Subject(s)
Sulfanilamides/analysis , Sulfathiazoles/analysis , Chromatography, High Pressure Liquid , Hydrogen-Ion Concentration , Indicators and Reagents , Solutions , Spectrophotometry, Ultraviolet , Tablets
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