University of North Florida
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Contact Info

Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Rosa Puchades

Abbrev:
Puchades, R.
Other Names:
Address:
Departamento de Qu’mica, Universidad PolitŽcnica de Valencia, Camino de Vera 14 46071 Valencia Spain
Phone:
+34-96-38-73416
Fax:
+34-96-38-77349

Citations 7

"Determination Of Free Fatty Acids In Foods By Flow Injection"
J. Sci. Food Agric. 1994 Volume 66, Issue 4 Pages 473-478
Rosa Puchades*, Alicia Suescun, Angel Maquieira

Abstract: Milk fat from cow and ewe milk was extracted by the method of Garcia Olmedo et al. (Anal. Bromatol., XXXI, 227) using a rotary evaporator instead of a Soxhlet extractor. Cocoa butter was extracted using the industrial process of NATRA SA (Valencia, Spain). The extracts or olive oils were homogenized with toluene in an ultrasonic bath and the homogenate injected into a carrier stream of toluene (0.95 ml/min). The carrier stream merged with a reagent stream of aqueous copper acetate/pyridine reagent of pH 6.1 (0.84 ml/min) and the solutions were mixed in a reaction coil (30 cm x 3 mm diameter). The mixed solution passed into a phase separator containing a lipophilic membrane and the copper-pyridine colored complex in the organic phase was measured spectrophotometrically at 716 nm. The calibration graph for oleic acid was linear for 0.1-5 M with reproducibility RSD (n = 12) of 1.9% at 0.3 mM and 0.8% at 2 mM. The precision RSD (n = 3) was 1.09% and recoveries were 98-101%. The effects of interferences on the method is discussed.
Fatty acids, free Food Spectrophotometry Method comparison

"Comprehensive Overview On The Application Of Flow Injection Techniques In Immunoanalysis"
Crit. Rev. Anal. Chem. 1992 Volume 23, Issue 4 Pages 301-321
R. Puchades; A. Maquieira; J. Atienza; A. Montoya

Abstract: A review is presented, with 94 references, on the application of flow injection techniques in immunoanalysis. Recent developments and new trends in flow injection immunoanalysis, such as immunosensors, are also discussed. A review and discussion with 94 references on the applications of flow injection techniques in immunoanalysis as well as examples of various immunoanalysis formats commonly employed to visualize the primary antibody-antigen reaction. Recent developments and new trends in the field of flow injection coupled to immunoassays, such as immunosensors, are also considered.
Immunoassay Review

"Flow Injection Analysis Of Seawater. 2. Cationic Species"
Crit. Rev. Anal. Chem. 1992 Volume 23, Issue 1-2 Pages 1-14
J. Atienza; M. A. Herrero; A. Maquieira; R. Puchades

Abstract: A review is presented, with 78 references. A summary of flow injection methods proposed for the determination of cationic species, viz., ammonia, alkaline-earth cations and trace elements, in seawater is given in tabular form and includes details of calibration ranges, detection limits, coefficient of variation and sampling frequencies (h-1). A review, with 78 references is given. Flow injection analysis (FIA) can provide a simple and versatile tool to determine metal cations in seawater. The use of FIA techniques coupled with online sample pre-concentration and matrix modification has recently attracted considerable research effort in attempts to control interference effects. The most common active agents used for sample pre-concentration are chelating resins of different types. The combination of FIA with detection techniques, such as atomic spectroscopy, for the determination of cationic species in the general context of seawater anal. is discussed.
Cations Sea Review Interferences

"Flow Injection Analysis Of Seawater: Anionic And Organic Species"
Crit. Rev. Anal. Chem. 1991 Volume 22, Issue 5 Pages 331-344
J. Atienza; M. A. Herrero; A. Maquieira; R. Puchades

Abstract: Methodology for the analysis of compounds in seawater has developed rapidly during recent years, together with a markedly increased interest in chemical data to characterize the marine environment. Flow injection analysis (FIA) can play a significant role in laboratory automation for many traditional wet chemical methods, and can serve as the basis for new methods which have no conventional analog. The FIA technique permits the analysis of a great number of samples, rapidly and reliably. This review discusses the present status and potential applications of FIA in the determination of anions and organic species in seawater analysis.
Anions Organic compounds Sea Review

"Evaluation Of The Dialysing Yield Of Membranes With Different Composition. Application To The Analysis Of Chloride In Fruit Juices By Flow Injection"
Anal. Chim. Acta 1997 Volume 353, Issue 2-3 Pages 245-254
S. Morais, M. I. Alcaina-Miranda, F. Lázaro, M. Planta, A. Maquieirá and R. Puchades

Abstract: In this paper, several home-made dialysing membranes with a high yield (around 56%) have been obtained allowing the easy and rapid analysis of minor components in food samples. Commercially available and home-made membranes with different chemical composition were tested by using a flow injection manifold. Polyetherimide-composed membranes (PEI) were selected because they showed a high dialysing yield and analytical signal, low blank signal and absence of membrane clogging. The influence of polymer concentration as well as the coagulation temperature on the membrane performance is discussed. A PEI membrane with 18% polymer concentration and around 40°C as coagulation temperature was found to be the most suitable manufactured membrane to achieve the proposed aims. The photometric determination of chloride ion was used for membrane characterisation. To test the membrane, an on-line dialysis flow injection procedure was used in the analysis of chloride in fruit juices and derivatives with an easy-going pre-treatment. A good correlation between the flow injection manifold (linear range: 20-250 mg/l, RSD 1.1%, average recovery 102.2% and sampling frequency 25 h-1) and the reference method is obtained. The use of this membrane in on-line dialysis prior to the photometric determination of minor components in fruit derivatives is a simple and low-cost alternative to usual approaches.
Chloride Fruit Dialysis Membrane

"Development Of An Automated Controlled-pore Glass Flow-through Immunosensor For Carbaryl"
Anal. Chim. Acta 1997 Volume 347, Issue 1-2 Pages 199-205
M. A. González-Martínez, S. Morais, R. Puchades*, A. Maquieira, A. Abad and A. Montoya

Abstract: The application of controlled-pore glass (CPG) as solid support for immobilization of immunoreagents in order to develop flow-through immunosensors is described. Monoclonal antibodies (MAbs) to carbaryl were site-directed immobilized on CPG through covalent attachment of their oxidized carbohydrate moieties to amine groups generated on the surface of silanyzed CPG. The automated immunosensor system is based on the LIB-CNA36 MAb in a direct competitive assay format, with horseradish peroxidase as enzyme label and fluorimetric detection. The dynamic range of the sensor is 0.05-1 µg l-1, with a detection limit of 0.029 µg l-1, being sensitive enough to be applied to drinking water samples without pre-concentration. The immobilized antibody reactor is able to run a whole assay in 20 min, and is reusable for more than 100 of consecutive assay cycles without significant loss of performance. The recognition of l-naphthol - the main metabolite of carbaryl - and other N-methylcarbamate insecticides are also studied, none of these compounds showing cross-reactivity higher than 7%. A preliminary validation of the immunosensor, carried out by analyzing real samples spiked with carbaryl, shows good results for bottled water and for commercial honey diluted with PBS (1 gl-1) as the only sample pretreatment.
Carbaryl Sensor Controlled pore glass

"Automated Determination Of Total Acidity In Wines By Flow Injection Analysis"
Am. J. Enol. Vitic. 1993 Volume 44, Issue 1 Pages 118-120
Miguel Peris-Tortajada, A. Maquieira, and R. Puchades

Abstract: Two automatic flow injection methods for the determination of total acidity in wine based on an acid-base titration are proposed. Their usefulness was tested by applying them to different wine samples (red, rosé, and white). The results obtained agree with those provided by a batch standard method. The features of both methods make them suitable for adaptation to enological laboratories with a view to continuous or irregular monitoring.
Acidity Wine Automation