University of North Florida
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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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Renewable surface

Classification: Solid phase -> Renewable surface

Citations 12

"Flow Injection Renewable Surface Techniques"
Anal. Chim. Acta 1995 Volume 308, Issue 1-3 Pages 14-19
Jaromir Ruzicka

Abstract: The principles of flow injection - renewable surface techniques are presented. The technique uses polymer particles, such as those used in chromatography, as reagent carriers. A small amount of the polymer was injected into the carrier stream and deposited in a jet-ring cell prior to injection of the analyte. Two examples of this technique ware described, namely: (i) the competitive immunoassay of the herbicide imazethepyr with fluorimetric detection; and (ii) the determination of Cr(VI) with reflectance spectrophotometric detection. For (i) imazethepyr competes with fluorescein-labelled imazethepyr for antimidazine mAb attached to Protein A conjugated beads. The calibration range was 5-5000 ng/ml and the RSD was 5% at the 2500 ng/ml level. For (ii) the reagent 1,5-diphenylcarbazide was adsorbed on to Polysorb C-18 beads. The calibration graph for Cr(VI) was linear for 10^-200 ng/ml at 540 nm and with a 500 µL injection volume.
Chromium Imazethapyr Spectrophotometry Fluorescence

"Sequential Injection Analysis For Electrochemical Measurements And Process Analysis"
Analyst 1994 Volume 119, Issue 11 Pages 2309-2314
Gary D. Christian

Abstract: An overview is presented on sequential-injection analysis (SIA). The principles of SIA and some of its operational parameters are briefly described. Examples are provided to show that SIA is a versatile solution handling system for electrochemical and process systems. The examples given include coulometric titration with automated dilution, potentiometric studies using the matched potential method for assessing relative potentiometric selectivity coefficients, and the incorporation of the jet ring (fountain) cell in an SIA manifold for development of renewable reaction surfaces and sensors. (40 references).
Electrochemical analysis Coulometry Potentiometric stripping analysis

"Bioligand Interaction Assay By Flow Injection Absorptiometry Using A Renewable Biosensor System Enhanced By Spectral Resolution"
Analyst 1998 Volume 123, Issue 7 Pages 1617-1623
J. Ruzicka

Abstract: Conventional biosensors, such as those based on surface plasmon resonance, lack spectral resoln. and employ a permanent sensing layer that needs to be activated and also regenerated after use. In contrast, scanning of the UV/VIS spectrum of agarose beads, trapped in a specially designed flow cell, allows real time monitoring of labeled and unlabeled biomolecules, with spectral resoln., on a surface that can be automatically renewed, by microfluidic manipulation. Agarose beads are identical with column materials used in affinity chromatography and therefore are readily available, derivatized with a wide choice of bioligands. In this way, flow injection absorptiometry on renewable surfaces provides a basis for a new class of biosensors with 'open architecture' that allows the development of novel types of immunoassays employing both unlabeled and labeled molecules. The method also has interesting implications for affinity chromatography, because it uses identical materials and investigates the same type of bioligand interactions. An improved configuration of the jet ring cell is introduced and it is shown that both large (IgG) and small molecules (biotin) can be detected down to the 25 ng level reproducibly and rapidly.
Biotin Immunoglobulin G Sensor Spectrophotometry

"Jet Ring Cell: A Tool For Flow Injection Spectroscopy And Microscopy On A Renewable Solid Support"
Anal. Chem. 1993 Volume 65, Issue 24 Pages 3566-3570
Jaromir Ruzicka, Cy H. Pollema, and Kurt M. Scudder

Abstract: The cited flow-cell is described and illustrated. It exploits radial flow-through a narrow ring-shaped gap (20-50% of the particle diameter) to retain suspended particles within a well-defined detection region; trapped particles can be removed instantaneously by flow reversal. The cell was characterized by analysis of various beads (e.g., Polysorb MP1 and Sephadex) stained with dyes or fluorescent reagents and suspended in suitable buffers, using a sequential injection system with a flow-rate of 2.5 ml/min, a reverse flow-rate of 10 ml/min, a carrier solution of 0.01 M sodium borate buffer and a microscope system equipped with an epifluorescence attachment (details given). Cytodex 3 beads covered by adherent, stained BHK cells were also used with a carrier solution of HEPES buffer. The cell should prove useful for automated immunoassays and monitoring the pre-concentration of analytes on sorbents. A new flow cell design for spectroscopic measurements of suspensions, the jet ring cell, is introduced. This cell exploits radial flow-through a narrow ring-shaped gap to retain suspended particles within the detection region. This ring constitutes a detection volume of well- defined area from which the trapped particles can be instantaneously removed at will. The bed of particles thus forms a renewable surface, which can be probed by reflectance, fluorescence, or chemiluminescence using a microscope or optical fiber. This device should prove useful for microscopic study of cells, for automated immunoassays, and for pre-concentration of analytes on sorbents with in situ spectroscopic detection. In conjunction with a fiber optic detection system, the jet ring cell becomes a component of a renewable chemical sensor system.
Fluorescence Chemiluminescence Chromatography Immunoassay Microscopy

"Flow Injection Renewable Surface Immunoassay: A New Approach To Immunoanalysis With Fluorescence Detection"
Anal. Chem. 1994 Volume 66, Issue 11 Pages 1825-1831
Cy H. Pollema and Jaromir Ruzicka

Abstract: Agarose beads (~35 µm) coated with goat anti-mouse IgG1 (heavy chain specific) were diluted 1:20 in 0.01 M phosphate buffer containing 0.5 M NaCl (buffer A) to give a suspension containing ~2 x 105 beads/ml. Portions (42 µL) of the suspension were pumped into the jet ring cell of the sequential injection system (diagram given). The beads were retained on a optical flat surface monitored by fluorescence microscopy with excitation at 450-490 nm and use of a 520 nm long-pass emission filter. For competitive assays, a mixture of unlabelled (sample) and R-Phycoerythrin-conjugated mouse IgG1 mAb diluted in buffer A was then pumped into the cell. Unbound sample was washed away, the signal change due to the bound labelled sample was measured, and the beads were then removed from the cell with a reversed buffer flow; buffer A was used as the carrier throughout (0.25-1 ml/min). The calibration graph was linear from 1-5 µg/ml of mouse IgG1 mAb (using 5 µg/ml of labelled antigen and a contact time of 25 s). The method was also applied to a non-competitive immunoassay (details given).
Immunoglobulin G Plasma Mouse Fluorescence Immunoassay

"A Liquid-drop What Is It Good For?"
Microchem. J. 1997 Volume 57, Issue 2 Pages 127-136
Hanghui Liu and Purnendu K. Dasgupta

Abstract: The unique features of liquid drops and their value for analytical systems are illustrated through a series of novel liquid drop-based systems: windowless optical cells, µliquid handling vessels, renewable gas samplers, and simple sample introduction interfaces. Drops are of particular value in solving problems in biphasic systems because of their truly renewable surfaces. (C) 1997 Academic Press. 27 References

"Automated Microanalysis Using Magnetic Beads With Commercial Capillary Electrophoretic Instrumentation"
J. Chromatogr. A 1997 Volume 781, Issue 1-2 Pages 197-204
Leonid G. Rashkovetsky, Yelena V. Lyubarskaya, Frantisek Foret, Dallas E. Hughes and Barry L. Karger*

Abstract: The potential of a new microanalytical method using magnetic beads (MBs) and commercial capillary electrophoresis (CE) instrumentation for performing enzymatic and inhibition assays, as well as for analysis of biological molecules such as antigens, substrates, etc., has been explored. A small quantity of magnetic beads containing immobilized biomolecules was injected into a neutral hydrophilic-coated fused-silica capillary. The short plug (2-3 mm) of beads was held fixed by a magnet placed in the cartridge of the CE system, without the use of frits. The beads could be replaced after each run, eliminating the need to regenerate the solid support. Two protocols were used for analysis: sequential injection (SI) and SI followed by isotachophoretic (ITP) focusing. Alkaline phosphatase (AP) and HIV-protease were used to demonstrate the SI procedure for enzymatic and inhibition assays. The second protocol, SI/ITP, was employed to quantitate an antigen (mouse mAB) using antibodies (sheep IgG towards mouse AB) immobilized on the beads. The MB-CE method, requiring only femtomole (fmol) quantities of material, can potentially be employed in diagnostic and forensic assays, kinetic studies and searching for inhibitors, ligands, receptors, etc.
Enzyme, alkaline phosphatase Enzyme, alkaline protease, HIV Antigen, mAB, mouse Blood Electrophoresis

"Automated Solid Phase Extraction Of Theophylline By Sequential Injection On Renewable Column"
Anal. Commun. 1998 Volume 35, Issue 11 Pages 357-359
Brian Dockendorff, David A. Holman, Gary D. Christian and Jaromir Ruzicka

Abstract: A miniaturized and fully automated solid phase extraction system was developed based on sequential injection onto a renewable microcolumn of an ion exchanger. Extraction of theophylline from caffeine solutions was used as an example of sample preparation An important feature, compared to commercial sorbent extraction systems, was the elimination of prepackaged sorbent cartridges by using an automatically renewable microcolumn. The method has evolved from recent innovations in sequential injection analysis using a jet ring cell that entraps ion exchanger beads and discards them after completion of the monitoring cycle.
Theophylline Ion exchange

"Development Of Electrochemical Immunosensing Systems With Renewable Surfaces"
Biosens. Bioelectron. 1998 Volume 13, Issue 1 Pages 7-17
Marta Santandreu, Sílvia Solé, Esteve Fàbregas and Salvador Alegret

Abstract: The repeated use of immunochemical modified solid phases in electrochemical immunosensor anal. is the driving interest of this work. Two new strategies have been developed. One of these strategies is aimed at the development of a manual methodology. It comprises the construction of amperometric immunosensors based on rigid biocomposites. These biocomposites are formed by a conducting polymer composite matrix that acts as a reservoir of an immobilized immunological material. The surface of the biocomposite can be renewed by a simple polishing procedure. The second strategy involves the design of an automatic methodology It features an immunochemical analysis system using the flow injection techniques. The potentiometric detection uses a solid phase formed by immunological reagents immobilized in magnetic particles. These particles are fixed to the sensor with the use of a magnetic field. The renewal of the reactive surface is achieved by the release and activation of the restraining magnetic field and the manipulation of the flow. The anal. properties of these immunosensors were evaluated measuring RIgG using a competitive technique and measuring GaRIgG with a sandwich methodology The labeling enzymes of the immunoconjugates were peroxidase in amperometric measurements and urease in potentiometric measurements.
Immunoglobulin G Amperometry Immunoassay Potentiometry

"Flow Detection System Using Chemical Sensor With Renewable Reaction Surface On A Solid Support"
Bunseki 1998 Volume 1998, Issue 11 Pages 881-883
Yamane, T.

Abstract: A review with 9 references is presented on jet-ring cell, application of flow injection renewable surface technology, and its future development.
Sensor

"Principles And Applications Of Flow Injection Analysis In Biosensors"
J. Mol. Recognit. 1996 Volume 9, Issue 5-6 Pages 316-325
Elo Harald Hansen

Abstract: In practical applications biosensors are often forced to operate under less than optimal conditions. Because of their construction, and the physical processes and chemical reactions involved in their operation, compromise conditions are frequently required to synchronize all events taking place. Therefore, and in order to implement functions such as periodic calibration, conditioning and possible regeneration of the biosensor, and, very importantly, to yield the freedom to select the optimum detection means, it is advantageous to use these devices in a flow-through mode, particularly by employing the flow injection (FI) approach. The capacity of FI, as offering itself as a complementary facility to augment the performance of biosensors, and in many cases as an attractive alternative, is demonstrated by reference to selected examples, comprising assays based on enzymatic procedures with optical and thermal detection procedures, and via description of a recently introduced technique for immunoassays, termed flow injection renewable surface immunoassays, which promises to entail powerful potentials and to yield compatible or better economy of operation than existing approaches.
Immunoassay Sensor

"Application Of Sequential-injection Analysis As Process Analyzers"
Lab. Rob. Autom. 1998 Volume 10, Issue 6 Pages 325-337
R. E. Taljaard, J. F. van Staden

Abstract: The development of sequential-injection analysis (SIA) from its mother technique flow injection analysis (FIA) is reviewed. A short historical background is given as well as discussions on the basic principles and operational parameters governing the design of an SLA system. Single-, double-, and multizone systems are described together with more complicated systems including calibration, dilution, extraction, dialysis, titrations, separation, pre-concentration, and systems incorporating mixing chambers.
d-Lactic acid Spectrophotometry