Micro-sequential injection

Long, X., M. Miro, R. Jensen, and E.H. Hansen. 2006. Highly selective micro-sequential injection lab-on-valve (pSI-LOV) method for the determination of ultra-trace concentrations of nickel in saline matrices using detection by electrothermal atomic absorption spectrometry. Anal. Bioanal. Chem. 386 739-748. 

C.-H. Wu, L. Scampavia, J. Ruzicka, B. Zamost, Micro sequential injection fermentation monitoring of ammonia, glycerol, glucose, and free iron using the novel lab-on-valve system, Analyst 126 (2001) 291. 

M. Grand, HM. Oliveira, J. Ruzicka, C. Measures, Determination of dissolved zinc in seawater using micro-sequential injection lab-on-valve with fluorescence detection. Analyst 136 (2011) 2747—2755. 

Micro-sequential injection environmental monitoring of nitrogen and phosphate in water using lab-on-valve system furnished with a microcolumn. HC holding coil LOV lab-on-valve RC reaction coil. 

Wu, C.-H., L. Scampavia, and J. Ruzicka. 2003. Micro sequential injection Automated insulin derivatization and separation using a lab-on-valve capillary electrophoresis system. Analyst 128 1123-1130. 

Micro reactors allow the sequential injection of the reaction partners, rather than introducing them in one step. By this means, the course of the reaction, in particular concerning the dynamic evolution of the concentration of reactants, may be changed. It is hoped that this may impact on selectivity. 

Chomchoei, R., Miro, M., Hansen, E. H., and Shiowatana, J. (2005b). Sequential injection system incorporating a micro-extraction column for automatic fractionation of metal ions in solid samples comparison of the extraction profiles when employing uni-, bi-, and multi-bidirectional flow plus stopped flow sequential extraction modes. Anal. Chim. Acta. 536, 183 — 190. 

The bead injection system was designed to operate in the sequential injection mode. It is possible to carry out bead injection analysis in a low-cost flow injection system with a unidirectional pump and without a computer, mainly for applications where samples and reagents are abundant and when there is no need for micro-volume control. To this end, it is necessary to use a flow cell able to achieve bead retention, accommodation of chemical reactions and detection [87,88]. 

J.-H. Wang, E.H. Hansen, Interfacing sequential injection on-line preconcentration using a renewable micro-column incorporated in a Tab-on-valve system with direct injection nebulization inductively coupled plasma mass spectrometry, J. Anal. At. Spectrom. 16 (2001) 1349. 

Currently, pTAS [112] and sequential injection systems using the lab-on-valve approach [22] are more popular. The former exploits hydrodynamic injection and is now known as Lab-on-Chip due to the extreme reduction in dimensions. Reproducible analytical channels are made by micro-drilling, etching, photolithography or laser erasing, and different channel profiles can be obtained at a reasonable cost. 

R. Burakham, J. Jakmunee, K. Grudpan, Development of sequential injection-lab-at-valve (SI-LAV) micro-extraction instrumentation for the spectrophotometric determination of an anionic surfactant, Anal. Sci. 22 (2006) 137. 

J. Jakmunee, L. Pathimapomlert, S.K. Hartwell, K. Grudpan, Novel approach for mono-segmented flow micro-titration with sequential injection using a lab-on-valve system a model study for the assay of acidity in fruit juices, Analyst 130 (2005) 299. 

Shadpour et al. [81] and Osiri et al. [82] employed SDS micro-capillary gel electrophoresis (SDS p-CGE) and micellar electrokinetic capillary (MEKC) electrophoresis in the first and second dimensions, respectively, to sort intact proteins using a poly (methylmethacrylate), PMMA, microchip. A diagram of the microchip is shown in Fig. 4. The electrophoresis commenced in the first dimension for a prescribed amount of time and, then, the bands from the first dimension were sequentially injected into the second dimension for development. The 2D electrophoresis system could generate a peak capacity of 2,600 for proteins isolated from fetal calf serum (see Fig. 4). 

R. Burakham, S. Lapanantnoppakhun, J. Jakmunne, K. Grudpan, Exploiting sequential injection analysis with lab-at-valve (LAV) approach for on-line liquid-liquid micro-extraction spectrophotometry, Talanta 68... 

AJJ. Anthemidis, K.I.G. loannou. Development of a sequential injection dispersive liquid-liquid micro-extraction system for electrothermal atomic absorption spectrometry by using a hydrophobic sorbent material determination of lead and cadmium in natural waters. Anal. Chim. Acta 668 (2010) 35—40. A.N. Anthemidis, K.I.G. loannou. Sequential injection dispersive liquid-liquid microextraction based on fatty alcohols and poly(etheretherketone)-mmings for metal determination by flame atomic absorption spectrometry, Talanta 84 (2011) 1215—1220. 

Flow injection on renewable surfaces techniques (FI-RST [12,13]) are suitable for micro miniaturization, since their key component, the jet ring cell (Fig. 3), has in its present form a circular detection area of 800 microns and a depth of 50 to 1000 microns. This device, originally designed for FI microscopy of live adherent cells [13], has found its application in fluorescence based immunoassays and reflectance based UV-VIS spectroscopy. The sensing layer in the JR cell comprises several thousand 35 micron polymer beads, which serve as reactive surfaces for protein and reagent adsorption. The cell is a part of a sequential injection system, which allows, besides conventional FI operations (sample injection, carrier pumping, reagent addition) also injection of a well... 

The earliest applications of acoustic levitation in analytical chemistry were concerned with the development of various steps of the analytical process. Thus, Welter and Neidhart [72] studied the preconcentration of n-hexanol in methanol by solvent evaporation and the liquid-liquid extraction of n-hexanol from water to toluene in a levitated droplet, which they found to be efficient when using GC-FID with n-pentanol as internal standard. Solvent exchange of fluorescein from methylisobutyl ketone to aqueous sodium hydroxide was also accomplished. Sample concentration in an acoustically levitated droplet prior to injection into a CE equipped with an LIF or UV detector has also been accomplished [73,118]. The target analytes (namely, dansylated amino acids) were concentrated in the levitated drop and a limit of detection of 15 nM — much lower than the 2.5 pM achieved by hydrodynamic injection without preconcentration — was achieved following CE separation and quantification. For this purpose, 36000 sample droplets 2.3 pi in volume each were sequentially positioned in the acoustic Ievitator and evaporated. This example illustrates the potential of acoustic levitation for coupling to any type of detector for micro- or nanotrace analyses. 

Micro injection Exact direction of nucleic acid to a single cell One ceU after the other, that is, a slow, sequential method... 

Especially in micro injection molded parts, the question of further processing always arises. The smallest parts are often difficult and cost-intensive to further process. Through the use of multi-component injection molding, such assembly operations can be prevented. In this method, two or more different materials can be injected either simultaneously or sequentially and thereby create a composite part. 

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