Solvent delivery pump

Xie et al. [9] reported on-chip generation of gradient elution by using electrochemical pumping in LC-ESI, which contains two 3 p-L on-chip solvent reservoirs, two electrochemical pumps, and an ESI nozzle. Solvent pumping was controlled galvanostatically at a flow rate of 200 nL/min. The authors reported a higher electrical current was used to increase flow rate or to achieve 

Electroosmotic pumps lack mechanical parts and specific localization in the manifold, producing an even electroosmotic flow. Besides, the flow in interconnected and branched channels can be controlled by switching voltages only. Just two decades ago electroosmotic pumps were attractive and feasible ways for mobile phase flow into microfluidic devices [13] but in the 1990s the conventional pumps available showed a major problem with the high pressures 

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For the non-reactive tracer tests, a solution containing KI was introduced to the bottom of the column (up-flow mode) using a Rainin Model SD-200 solvent delivery pump. The first non-reactive tracer test was performed after complete water saturation of a column. PCE was then introduced into the bottom of the column using a Harvard Apparatus Model 22 syringe pump at a flow rate of 0.33 mL/min. When approximately 70% of the pore volume... 

Williams et al. used a high performance liquid chromatographic assay method for dipyridamole monitoring in plasma [71]. The HPLC system uses a Waters model 6000 A solvent delivery pump equipped with a U6K injector, a pBondapak C 9 column (30 cm x 39 mm 10 pm), and a Model 440 absorbance detector. The signal from the detector was quantified using a Shimadzu data processor and an Omni-Scribe recorder. A mobile phase flow rate of 1.5 mL/min was produced by a pressure of approximately 102 atm (1500 p.s.i.). The mobile phase was 50 50 mixture of acetonitrile and 0.01 M sodium phosphate in water (adjusted to pH 7). The absorbance reading of dipyridamole in methanol was made at 280 nm. 

Refer to the manufacturer s solvent delivery (pump) manual, if necessary. 

The analytical HPLC column used for analysis was packed in 300 x 3.9 nin stainless column with Lichrospher lOORP-18 packing(lS urn, Merck Co.). The HPLC used for analysis consists of a M930 Solvent Delivery Pump, a 486 detector (M 7200 Absorbance Detector) from Young-ln Scientific Co, and a Rheodyne injection valve (20 pi sample loop). Autochrowin (ver. 1.42, Young-ln Scientific Co.) connected to PC was used as data acquisition system. 

The most important parts of the instruments are the pumps for maintaining constant, pulseless rates of flow, the column types for the molecular weight range of analysis, and the detector system see Table 3.12. Some of the popular types of solvent delivery pumps include syringe pumps, the plunger of which is actuated by a screw-fed stepper motor, and the dual piston reciprocating pumps, which may have the pistons in either series or parallel see Figure 3.19 (79). 

Figure 7.16 Chromatotron Model 8924 with solvent delivery pump. The Chromatotron Model 7924 shown schematically in Figure 7.18 differs from the 8924 only in the use of a Teflon funnel, instead of a pump, for solvent supply. (Photograph courtesy of Harrison Research Inc., Palo Alto, CA.)...

HPLC/A, HPLC/C The system consisted of two solvent delivery pumps, a reaction coil and Metachem Polaris C18A reversed-phase column and a CouIAiray electrochemical detector. The electrochemical detector includes two flow cells 0.09 No data 6.0 Pharmaceuticals, fruits, human blood serum 2008 251... 

A Beckman series of liquid chromatograph equipped with a Model I65 variably wavelength detector, a Modell II4 solvent delivery pump, a Model 420 controller and a Model C-R3A Shimadzu integrator was used to perform the chromatographic separation of carotenoids, tocopherols and organic acid under different conditions which are shown in the figures or tables. 

In the standard laboratory-based form of the instrumentation, a Model 6000A solvent delivery pump was employed in conjunction with a Model U6K universal injector both obtained from Waters Associates. In the first version of an automated system, the solvent delivery pump remained, but the manual injector was replaced by its automatic counterpart, the Model 7126 Automatic Sample Injector from Rheodyne. 

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