http://mdpi.com/journal/sensors/special_issues/sensors-in-flow-analysis/ Submission Sensors is a highly rated journal with a 1.870 impact factor in 2008. Sensors is indexed and abstracted very quickly by Analytical Abstracts, Chemical Abstracts (CAS), Chemistry Citation Index, Directory of Open Access Journals (DOAJ), Google Scholar, IndexCopernicus, INSPEC, Journal Citation Report, Open-J-Gate, Science Citation Index Expanded (SCIE), Scirus, SciSearch and Scopus. All papers should be submitted to sensors@mdpi.org with copy to the guest editors. To be published continuously until the deadline and papers will be listed together at the special websites. Please visit the Instructions for Authors page before submitting a paper. Open Access publication fees are 1050 CHF per paper. English correction fees (250 CHF) will be added in certain cases (1300 CHF per paper for those papers that require extensive additional formatting and/or English corrections.). http://mdpi.com/1424-8220/7/2/166/ In this paper we describe a low-cost spectrometric detector that can be easily assembled in a laboratory for less than €80 with a minimal number of optical components and which has proved sensitive and flexible enough for real-life applications. The starting point for the idea to construct this small, compact low-cost spectrometric detector was the decision to use a tri-colour light-emitting diode (LED) of the red-green-blue (RGB) type as a light source with the objective of achieving some flexibility in the selection of the wavelength (430 nm, 565 nm, 625 nm) but avoiding the use of optical fibres. Due to the dislocation of the emitters of the different coloured light, the tri-colour LED-based detector required an optical geometry that differs from those that are described in literature. The proposed novel geometry, with a coil-type glass flow-through cell with up to four ascending turns, proved useful and fit for the purpose. The simplicity of the device means it requires a minimal number of optical components, i.e., only a tri-colour LED and a photoresistor. In order to make a flow-injection analysis (FIA) with the spectrometric detector even more accessible for those with a limited budget, we additionally describe a low-cost simplified syringe-pump- based FIA set-up (€625), the assembling of which requires no more than basic technical facilities. We used such a set-up to test the performance of the proposed spectrometric detector for flow-injection analyses. The tests proved its suitability for real-life applications. The design procedures are also described. http://mdpi.com/1424-8220/7/2/166/ Fri, 23 Feb 2007 00:00:00 CET Sensors 2007-02-23 7 2 Article 166 184 1424-8220 A Novel Type of Tri-Colour Light-Emitting-Diode-Based Spectrometric Detector for Low-Budget Flow-Injection Analysis 2007-02-23 doi: 10.3390/s7020166 Nataša Gros http://mdpi.com/1424-8220/7/1/75/ Electromagnetic flowmeters are used to measure the speed of water flow in water distribution systems. Corrosion problem in metal pipelines can be solved by cathodic protection methods. This paper presents a research on corruptive effects of the cathodic protection system on electromagnetic flowmeter depending on its measuring principle. Experimental measurements are realized on the water distribution pipelines of the Izmir Municipality, Department of Water and Drainage Administration (IZSU) in Turkey and measurement results are given. Experimental results proved that the values measured by the electromagnetic flowmeter (EMF) are affected by cathodic protection system current. Comments on the measurement results are made and precautions to be taken are proposed. http://mdpi.com/1424-8220/7/1/75/ Fri, 26 Jan 2007 00:00:00 CET Sensors 2007-01-26 7 1 Article 75 83 1424-8220 E.M.I Effects of Cathodic Protection on Electromagnetic Flowmeters 2007-01-26 doi: 10.3390/s7010075 Serdar Gundogdu Ozge Sahin http://mdpi.com/1424-8220/6/11/1555/ The construction and characterization of a flow-through polarographic detectorfor catalyzing the electroreduction of N-nitrosodiethanolamine (NDELA), is discussed. Theflow-through cell is equipped with a gold wire electrode (a thin mercury film deposited on agold substance). The response is evaluated with respect to substance diameter, length,concentration of modifying film, operating potential, supporting electrolyte and pH, andflow rate in the DC mode. The system allows the determination of N-nitrosodiethanolaminein rabbit biological fluids with relatively inexpensive equipment. http://mdpi.com/1424-8220/6/11/1555/ Sat, 11 Nov 2006 00:00:00 CET Sensors 2006-11-11 6 11 Article 1555 1567 1424-8220 Design of a Flow-through Polarographic Sensor Based on Metal Films for Determining N-nitrosodiethanolamine Levels in Rabbit Biological Fluids 2006-11-11 doi: 10.3390/s6111555 Lai-Hao Wang Hung-Chang Hsia Yuan-Zhi Lan http://mdpi.com/1424-8220/6/11/1498/ Miniaturization and integration of chemical devices into modules that aredimensionally comparable with electronic chips (Lab on Chip) is nowadays developingworldwide. The aim of our work was to suggest and optimize the best conditions forfabrication of TFT sensor due to its sensitivity and low experimental deviations. Newelectrochemical analytical device was developed to ensure certain known mass transport toelectrodes, which is the most limiting process that influencing the response quality of thesensor. The device consists from rotating conic vessel for measured sample and stick-inthick-film sensor. The sensors responses were tested under trace analysis of cadmium.Measurements were done also with the others electrochemical arrangements to comparewith the new one. The sensor output current response dependence on the liquid velocity andgeometrical arrangement within using standard electrochemical couple of potassiumferrocyanide-ferricyanide is presented. We found out that the new device with controlledflow of electrolyte to sensor worked properly and gave satisfactory results. http://mdpi.com/1424-8220/6/11/1498/ Mon, 06 Nov 2006 00:00:00 CET Sensors 2006-11-06 6 11 Article 1498 1512 1424-8220 New Hydrodynamic Electrochemical Arrangement for Cadmium Ions Detection Using Thick-Film Chemical Sensor Electrodes 2006-11-06 doi: 10.3390/s6111498 Jan Prasek Martin Adamek Jaromir Hubalek Vojtech Adam Libuse Trnkova Rene Kizek http://mdpi.com/1424-8220/6/11/1483/ Acetylsalicylic acid (AcSA), or aspirin, was introduced in the late 1890s and hasbeen used to treat a variety of inflammatory conditions. The aim of this work was to suggestelectrochemical sensor for acetylsalicylic detection. Primarily, we utilized square wavevoltammetry (SWV) using both carbon paste electrode (CPE) and of graphite pencilelectrode (GPE) as working ones to indirect determination of AcSA. The principle ofindirect determination of AcSA bases in its hydrolysis on salicylic acid (SA), which isconsequently detected. Thus, we optimized both determination of SA and conditions forAcSA hydrolysis and found out that the most suitable frequency, amplitude, step potentialand the composition and pH of the supporting electrolyte for the determination of SA was260 Hz, 50 mV, 10 mV and Britton-Robinson buffer (pH 1.81), respectively. The detectionlimit (S/N = 3) of the SA was 1.3 ng/ml. After that, we aimed on indirect determination ofAcSA by SWV CPE. We tested the influence of pH of Britton-Robinson buffer andtemperature on yield of hydrolysis, and found out that 100% hydrolysis of AcSA wasreached after 80 minutes at pH 1.81 and 90°C. The method for indirect determination ofAcSA has been utilized to analyse pharmaceutical drug. The determined amount of AcSA in the pharmaceutical drug was in good agreement with the declared amounts. Moreover, weused GPE for determination of AcSA in a pharmaceutical drug. Base of the results obtainedfrom stationary electrochemical instrument we used flow injection analysis withelectrochemical detection to determine of salicylates (SA, AcSA, thiosalicylic acid, 3,5-dinitrosalicylic acid and 5-sulfosalicylic acid – SuSA). We found out that we are able todetermine all of detected salicylates directly without any pre-treatment, hydrolysis and so onat units of femtomoles per injection (5 μl). http://mdpi.com/1424-8220/6/11/1483/ Mon, 06 Nov 2006 00:00:00 CET Sensors 2006-11-06 6 11 Article 1483 1497 1424-8220 Electrochemical Sensors for Detection of Acetylsalicylic Acid 2006-11-06 doi: 10.3390/s6111483 Veronika Supalkova Jiri Petrek Ladislav Havel Sona Krizkova Jitka Petrlova Vojtech Adam David Potesil Petr Babula Miroslava Beklova Ales Horna Rene Kizek http://mdpi.com/1424-8220/6/11/1466/ Naphthoquinones are one of the groups of secondary metabolites widespread innature, where they mostly appear as chromatic pigments. They embody broad-range ofbiological actions from phytotoxic to fungicidal. An anticancer effect of naphthoquinonesstimulates an interest in determination and characterization of single derivatives of 1,2- and1,4-quinones in biological samples. The main aim of this work was to suggest a techniquesuitable to determine lawsone, juglone and/or plumbagin in biological samples and to studyof their influence on BY-2 tobacco cells. The BY-2 tobacco cells were cultivated in thepresence of the naphthoquinones of interest (500 μg.l-1) for 24 h and then the morphologicalchanges were observed. We found out that naphthoquinones triggered the programmed celldeath at BY-2 cells, which can be confirmed by the apoptotic bodies in nucleus. After thatwe suggested and optimized different electrochemical techniques such differential pulsevoltammetry (DPV) coupled with hanging mercury drop (HMDE) and carbon pasteelectrode, micro flow device coupled with carbon screen printed electrodes and flowinjection analysis coupled with Coulochem III detector to determine them. The detectionlimits of naphthoquinones of interest were expressed as 3S/N and varied from units tohundreds of ng per millilitres according to methods used. Moreover, we utilized DPVcoupled with HMDE and micro flow device to determine content of juglone in leavesPersian walnut (Juglans regia). We determined that the leaves contained juglone tenths of gper 100 g of fresh weight. The results obtained show the convincing possibilities of using ofthese methods in analysis of plant secondary metabolites. http://mdpi.com/1424-8220/6/11/1466/ Mon, 06 Nov 2006 00:00:00 CET Sensors 2006-11-06 6 11 Article 1466 1482 1424-8220 Flow Injection Analysis Coupled with Carbon Electrodes as the Tool for Analysis of Naphthoquinones with Respect to Their Content and Functions in Biological Samples 2006-11-06 doi: 10.3390/s6111466 Petr Babula Dalibor Huska Pavel Hanustiak Jiri Baloun Sona Krizkova Vojtech Adam Jaromir Hubalek Ladislav Havel Milan Zemlicka Ales Horna Miroslava Beklova Rene Kizek http://mdpi.com/1424-8220/6/10/1383/ Some recent analytical sensors based on electrochemical and optical detectioncoupled with different flow techniques have been chosen in this overview. A briefdescription of fundamental concepts and applications of each flow technique, such as flowinjection analysis (FIA), sequential injection analysis (SIA), all injection analysis (AIA),batch injection analysis (BIA), multicommutated FIA (MCFIA), multisyringe FIA(MSFIA), and multipumped FIA (MPFIA) were reviewed. http://mdpi.com/1424-8220/6/10/1383/ Tue, 24 Oct 2006 00:00:00 CEST Sensors 2006-10-24 6 10 Review 1383 1410 1424-8220 Recent Electrochemical and Optical Sensors in Flow-Based Analysis 2006-10-24 doi: 10.3390/s6101383 Orawon Chailapakul Passapol Ngamukot Alongkorn Yoosamran Weena Siangproh Nattakarn Wangfuengkanagul http://mdpi.com/1424-8220/6/10/1321/ Since twelve years the Chromatomembrane Cell has been proposed as a new andversatile device for extraxtion procedures in the flow based analysis. In the meantime aremarkable number of papers was submitted dealing with applications of the novel methodto all the conceivable varieties of flow injection and sequential injection analysis. Thedevice supports important analytical procedures such as sampling, sample preparation, andpreconcentration each being combined with a phase transfer of the analyte. TheChromatomembrane Cell can be coupled to most of the modern detectors which workcomputer aided in the laboratories of today. Centrepiece of the cell is a block made frombiporous hydrophobic PTFE, inside which polar (in the macropores) and nonpolar (in themicropores) solvents come into a close contact with each other and might flowindependently with different flow rates. Microporous PTFE membranes prevent polarphases from their flowthrough into directions which are reserved for nonpolar fluids only.Thus, a strict control over the fluxes can be established at the analysts request. Especially,that PTFE block offers outstanding possibilities as a sampling unit for air monitoring. http://mdpi.com/1424-8220/6/10/1321/ Tue, 17 Oct 2006 00:00:00 CEST Sensors 2006-10-17 6 10 Review 1321 1332 1424-8220 Gas/Liquid and Liquid/Liquid Solvent Extraction in Flow Analysis with the Chromatomembrane Cell 2006-10-17 doi: 10.3390/s6101321 Leonid N. Moskvin Juergen Simon http://mdpi.com/1424-8220/6/10/1245/ Optical techniques for chemical analysis are well established and sensors based on thesetechniques are now attracting considerable attention because of their importance in applications suchas environmental monitoring, biomedical sensing, and industrial process control. On the other hand,flow injection analysis (FIA) is advisable for the rapid analysis of microliter volume samples and canbe interfaced directly to the chemical process. The FIA has become a widespread automatic analyticalmethod for more reasons; mainly due to the simplicity and low cost of the setups, their versatility, andease of assembling. In this paper, an overview of flow injection determinations by using opticalchemical sensors is provided, and instrumentation, sensor design, and applications are discussed. Thiswork summarizes the most relevant manuscripts from 1980 to date referred to analysis using opticalchemical sensors in FIA. http://mdpi.com/1424-8220/6/10/1245/ Tue, 10 Oct 2006 00:00:00 CEST Sensors 2006-10-10 6 10 Review 1245 1307 1424-8220 Recent Development in Optical Chemical Sensors Coupling with Flow Injection Analysis 2006-10-10 doi: 10.3390/s6101245 Catalina Bosch Ojeda Fuensanta Sánchez Rojas http://mdpi.com/1424-8220/6/10/1224/ A flow-through spectrophotometric bulk optode for the flow-injectiondetermination of thiocyanate is described. As active constituents, the optode incorporatesthe lipophilized pH indicator 5-octadecanoyloxy-2-(4-nitrophenylazo)phenol andmethyltridodecyl ammonium chloride, dissolved in a plasticized poly(vinyl)chloridemembrane entrapped in a cellulose support. The optode is applied, in conjunction with theflow injection technique, to the determination of thiocyanate at pH 7.5 (TRIS/H2SO4). Thesensor is readily regenerated with a 10-2 M NaOH carrier solution. The analyticalcharacteristics of this optode with respect to thiocyanate response time, dynamicmeasurement range, reproducibility and selectivity are discussed. The proposed FI methodis applied to the determination of thiocyanate in waters from different sources and in humansaliva samples in order to distinguish between smokers and non-smokers. http://mdpi.com/1424-8220/6/10/1224/ Mon, 09 Oct 2006 00:00:00 CEST Sensors 2006-10-09 6 10 Article 1224 1233 1424-8220 Flow-through Bulk Optode for Spectrophotometric Determination of Thiocyanate and Its Application to Water and Saliva Analysis 2006-10-09 doi: 10.3390/s6101224 Soledad García Joaquín A. Ortuño Concepción Sánchez-Pedreño Isabel Albero José Fernández http://mdpi.com/1424-8220/6/10/1161/ This review gives a survey on the state of the art of pesticide detection usingflow-based biosensing systems for sample screening. Although immunosensor systems havebeen proposed as powerful pesticide monitoring tools, this review is mainly focused onenzyme-based biosensors, as they are the most commonly employed when using a flowsystem. Among the different detection methods able to be integrated into flow-injectionanalysis (FIA) systems, the electrochemical ones will be treated in more detail, due to theirhigh sensitivity, simple sample pretreatment, easy operational procedures and real-timedetection. During the last decade, new trends have been emerging in order to increase theenzyme stability, the sensitivity and selectivity of the measurements, and to lower thedetection limits. These approaches are based on (i) the design of novel matrices for enzymeimmobilisation, (ii) new manifold configurations of the FIA system, sometimes includingminiaturisation or lab-on-chip protocols thanks to micromachining technology, (iii) the useof cholinesterase enzymes either from various commercial sources or genetically modifiedwith the aim of being more sensitive, (iv) the incorporation of other highly specificenzymes, such as organophosphate hydrolase (OPH) or parathion hydrolase (PH) and (v) thecombination of different electrochemical methods of detection. This article discusses thesenovel strategies and their advantages and limitations. http://mdpi.com/1424-8220/6/10/1161/ Sun, 01 Oct 2006 00:00:00 CEST Sensors 2006-10-01 6 10 Review 1161 1186 1424-8220 Trends in Flow-based Biosensing Systems for Pesticide Assessment 2006-10-01 doi: 10.3390/s6101161 Beatriz Prieto-Simón Mònica Campàs Silvana Andreescu Jean-Louis Marty http://mdpi.com/1424-8220/6/9/1118/ This paper presents a full 3D study of a shielded ECT sensor. The spatialresolution and effective sensing field are obtained by means of Finite Element Methodbased simulations and are the compared to a conventional sensor's characteristics. Aneffective improvement was found in the sensitivity in the pipe cross-section, resulting inenhanced quality of the reconstructed image. The sensing field along the axis of the sensoralso presents better behaviour for a shielded sensor. http://mdpi.com/1424-8220/6/9/1118/ Fri, 22 Sep 2006 00:00:00 CEST Sensors 2006-09-22 6 9 Article 1118 1127 1424-8220 Influence of Shielding Arrangement on ECT Sensors 2006-09-22 doi: 10.3390/s6091118 A. Martinez Olmos J. Alberdi Primicia J. L. Fernandez Marron http://mdpi.com/1424-8220/6/12/1837/ This work presents the construction and application of boron-doped diamond(BDD) thin film electrode as sensor for the determination of three β-agonists, viz.salbutamol, terbutaline and clenbuterol. Although well-known as a chemically inertmaterial, BDD film however shows fouling in detection of these compounds using fixedpotentialmode amperometry. A suitable waveform for pulsed amperometric detection(PAD) was developed and used to determine the agonist compounds. It was seen that thedeveloped PAD significantly refreshed the BDD surface for long-term detection in flowinjection analysis. Linear working ranges were 0.5-100 μM, 1.0-100 μM and 0.5-50 μM forsalbutamol, terbutaline and clenbuterol, respectively. The developed PAD-BDD system wasapplied to successfully determine salbutamol and terbutaline in commercial pharmaceuticalproducts. The methods were validated with a capillary electrophoresis method. http://mdpi.com/1424-8220/6/12/1837/ Thu, 26 Jan 2006 00:00:00 CET Sensors 2006-01-26 6 12 Article 1837 1850 1424-8220 Pulsed Amperometry for Anti-fouling of Boron-doped Diamond in Electroanalysis of β-Agonists: Application to Flow Injection for Pharmaceutical Analysis 2006-01-26 doi: 10.3390/s6121837 Chanpen Karuwan Thitirat Mantim Patcharin Chaisuwan Prapin Wilairat Kate Grudpan Piyada Jittangprasert Yasuaki Einaga Orawon Chailapakul Leena Suntornsuk Oraphan Anurukvorakun Duangjai Nacapricha