Laboratory Robotics and Automation最新文献

We developed an inexpensive continuous-type ultrasonic nebulizer for atomic spectrometry based on a domestic humidifier. With this nebulizer, the aerosol introduction rate is about 1.0 mL/min, much greater than that of pneumatic nebulizer. The long-term stability was also satisfactory because both the solution level and the coupling water temperature were held constant. The pumps controlled by a computer allow the nebulizer to work continuously. The results show that both the analytical performance and the cost were satisfactory. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:76–80, 2000

On the basis of the statistical characteristics of analyte lines and spectral interferences in inductively coupled plasma-atomic emission spectrometry (ICP–AES), the adaptive noise canceling model in the signal-processing technique has been applied to the correction of spectral interferences. Correction results of the simulated and experimental spectra have demonstrated the feasibility and effectiveness of this method. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:81–85, 2000

The present article covers a novel surface plasmon resonance (SPR) instrument based on simultaneous multiwavelength detection. The sensing principle of a traditional SPR device is based on fixing a discrete excitation wavelength and modulating the angle of incident light. The SPR-reflected spectra are shown in terms of reflected light intensity versus angle of incident light. The instrument presented here is designed on the basis of fixing the angle of incident light and measuring the change of resonant wavelength in the wavelength range of 400–800 nm. The SPR spectra are shown in terms of reflected light intensity versus wavelength of the incident light. The intensity of the reflected light is the minimum at the resonant wavelength. With the aid of the device, some chemical sensors and immunosensors, such as the thiolate chemical sensor, the fibrin immunosensor, and the albumin immunosensor were developed. The kinetic processes of formation of various sensing monolayers were studied in real time through observing the change of resonant wavelength. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:104–107, 2000

We present an overview on the recent development and future trends of sequential injection (SI) analysis for the automation of pharmaceutical analysis. The advantages and potentials of SI systems, namely, low sample and reagent consumption and high reliability and automatic manipulation, are discussed in applications to serial pharmaceutical analysis, pharmaceutical production process monitoring, drug-dissolution testing, and affinity ranking in drug screening. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:60–66, 2000

A semiautomatic method for mineral-phase analysis for ferrous iron (FeCO₃) using on-line leaching technique was developed. A flow-injection manifold is described, which makes on-line leaching of the powdered sample followed by color developing of Fe(II) with o-phenanthroline and its spectrophotometric determination possible. This method can produce meaningful results provided that the experimental conditions are kept at optimum values. The analysis time is greatly reduced by using flow injection techniques. Sample throughput was about 12 samples/hr with a method precision of 2.7% RSD, depending on the leaching time chosen and FeCO₃ content in ores. Analytical data were in good agreement with recommended values for analysis of standard references materials. For each analysis, 20–30 mg of powdered sample was required. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:86–90, 2000

Antimony was determined in alloy copper by on-line hydride generation atomic fluorescence spectrometry in an alkaline solution. Samples were dissolved with nitric acid. In order to eliminate serious chemical interferences caused by transition metals, the solution was then made alkaline with sodium hydroxide. Conditions for hydride generation in alkaline medium and parameters of the flow injection system were optimized. Compared with the traditional procedure for hydride generation, the proposed procedure is simple and effective. The method was used successfully for the determination of antimony in standard brass samples. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:114–117, 2000

1,10 Phenanthroline (phen) has been tested as a complexing agent, which is more stable and selective than sodium-diethyldithiocarbamate (DDTC) and ammonium-pyrrolidinedithiocarbamate (APDC), for on-line preconcentration of copper on RP-C₁₈ material in a microcolumn with a flow injection–flame atomic absorption spectrometer (Fl–FAAS) system. The on-line formed copper-phen complexes can be adsorbed on the C₁₈ sorbent material. Various parameters affecting the copper-phen complex formation and its subsequent adsorption on the microcolumn as well as its elution into the nebulizer of the atomic absorption spectrometer (AAS) were optimized. A 2.5 × 10⁻³ mol/L phen in 2% ethanol was mixed on-line with aqueous sample solution acidified with 0.1% (v/v) nitric acid and flowed through the microcolumn for 30 seconds. The adsorbed copper-phen complexes in the microcolumn were eluted with ethanol for 10 seconds into the nebulizer of AAS. A good precision (RSD = 3.0%; n = 14), high enrichment factor (32) and sample throughput (80 samples h⁻¹) with detection limit 0.3 μg/L were obtained. The method was applied to the standard reference materials such as sea water, mussels (biological), and GSS-1 (geological), for copper determination, and the results were in good agreement with the certified values. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:97–103, 2000

An automatic atomic fluorescence spectrometer, which consists of a reactor for vapor generation and an atomic fluorescence detector, is described in this paper. An intermittent reactor, which is simple in construction and reliable in use, is described and recommended. Specially designed hollow cathode lamp and high performance hollow cathode lamp have been successfully used as the light source in the instrument. Long lifetime, high stability, excellent detection limits and available for all the interested elements are the main advantages of the lamp. Several kinds of atomizer were compared and the result is reported in this paper. Some research results in the developing of the analytical methods suitable for the automatic instruments are also described. Using the automatic instrument, the detection limits obtained were: As, Pb, Ge, Sn, Se, Te, Bi, Sb < 9 × 10⁻¹¹ g ml⁻¹, Hg, Cd < 8 × 10⁻¹² g ml⁻¹ and Zn < 5 × 10⁻⁹ g ml⁻¹. The precision of the determination (R.S.D) was less than 2% and the throughput is around 120 determinations per hour. The instrument and its method of application have been widely used with great success in China for the determination of mercury and other hydride forming elements in geochemical sample, environmental sample, water, foodstuff, and alloy. © 2000 John Wiley & Sons, Inc. Lab Robotics and Automation 12:67–73, 2000