An automated fluid-transport device for a microfluidic system

An automated fluid-transport device for a chip-based capillary electrophoresis system has been developed. The device mainly consists of six peristaltic micropumps, two vacuum micropumps, microvalves, multi-way joints, titanium tubes, and a macro-to-micro connector. Various solutions used for the cleaning and activation of chip channels, and electrophoresis separation, are allowed to automatically transport to chip reservoirs by the electric control module. The performance of the whole system was characterized by the analysis of fluorescein sodium using chip electrophoresis with LED-induced fluorescence detection. The peak-height variation (RSD) was 3.8% in six cycles of analyses. Additionally, compared with conventional manual operation, the developed device can spare 60% time for chip pretreatment. This microdevice offers high-efficiency pretreatment for microchips, thereby resulting in a remarkable improvement of analytical capacity for batch samples.     

A software-programmable microfluidic device for automated biology

Specific-purpose microfluidic devices have had considerable impact on the biological and chemical sciences, yet their use has largely remained limited to specialized laboratories. Here we present a general-purpose software-programmable microfluidic device which is capable of performing a multitude of low- and high-level functions without requiring any hardware modifications. To demonstrate the applicability and modularity of the device we implemented a variety of applications such as a microfluidic display, fluid metering and active mixing, surface immunoassays, and cell culture. We believe that analogously to personal computers, programmable, general-purpose devices will increase the accessibility and advance the pervasiveness of microfluidic technology.     

An automated system for activation analysis with short half-life radionuclides using a carbonfiber irradiation facility

Contamination of rabbits during transfer in a fast irradiation facility has been reduced by development of a rabbit system containing no metal parts, and only plastic and carbonfiber. As a result, this system could be automated and has been equipped with a sample changer. Flexibility and versatility in the operation of this new system was attained by a combination of software and hardware control. With this new system, large-scale analysis can be performed with a considerable saving in man-power of the users.     

A high-performance X-ray system for medical device irradiation

A new concept of X-ray irradiator for low-density products on pallets is proposed. Monte Carlo simulations are applied to predict the performance of this system. The Monte Carlo predictions reveal in good agreement with experimental data obtained using products of different densities.     

Solid targets for 99mTc production on medical cyclotrons

Recent disruptions in the molybdenum-technetium generator supply chain prompted a review of non-reactor based production methods for both ⁹⁹Mo and ^99mTc. Small medical cyclotrons (E _p ~ 16–24 MeV) are capable of producing Curie quantities of ^99mTc from isotopically enriched ¹⁰⁰Mo using the ¹⁰⁰Mo(p,2n)^99mTc reaction. Unlike most other metallic target materials for routine production of medical radioisotopes, molybdenum cannot be deposited by reductive electroplating from aqueous salt solutions. To overcome this issue, we developed a new process for solid molybdenum targets based on the electrophoretic deposition of fine ¹⁰⁰Mo powder onto a tantalum plate, followed by high temperature sintering. The targets obtained were mechanically robust and thermally stable when irradiated with protons at high power density.     

An automated facility for neutron activation analysis

A fully automated neutron activation analysis (NAA) facility has been constructed at the Whiteshell Nuclear Research Establishment. This high-capacity facility has been designed for use with a wide variety of neutron sources, including Canada's SLOWPOKE II and MAPLE research reactors. Its pneumatic transfer system is driven by a Square-D Model 500 programmable controller, linked in turn to a Nuclear Data ND6700 computer/spectrometer. Custom software for data entry and system control has been combined with Nuclear Data software for gamma-spectrum acquisition and processing to create a flexible, easy-to-use facility for NAA. Its design and performance are discussed.     

An automated technique for thermoacoustimetry of solids

An automated technique for thermoacoustimetry of solids is described. The technique is illustrated by measurements on Green River and Kentucky oil shales.     

Development of an up-flow irradiation device for electron beam wastewater treatment

Electron beam irradiation processing is an available technology to treat sludge, groundwater, surface water and industrial and municipal wastewater. The use of this technology into environmental areas has moved slowly because industry and government are always conservative in the adoption of new processes, especially when they can not observe the efficiency and cost effectiveness of a treatment in a full scale facility.

In this direction the hydraulic system where the water is presented to the electron beam governs the efficacy of this technology. The present work is based on the development of the irradiation device, an up-flow delivery system that alleviates the dependence of energy transfer to the stream with the beam accelerating voltage (penetration capability).

In this work a series of experiments were performed to establish the relationships between accelerating voltage ranging from 0.5 to 1.5 MeV, current, water flow and deposited dose in order to optimize the operating parameters and the selection of a cost-effective commercial electron beam.     

An automated neutron activation system for short-lived nuclides

The present paper describes an attempt to create a reliable and easy to use system for neutron activation with short-lived nuclides, suitable to be used with several irradiation and counting procedures in instrumental neutron activation analysis (INAA) at the Portuguese Research Reactor. This system can become very useful for a large community within LNETI, as well as other national institutes and universities, particularly for those involved in studies where the analysis of a large number of samples is required. Selenium determination has been performed, through the short-lived nuclide^77mSe, as an example of the reliability of the system.     

An automated system for the determination of fluoride

A procedure is reported for the automated determination of fluoride by the method of standard addition. Additions of standard are made via a peristaltic pump and the amounts of standard added are computed from the change in weight of the standard in its container on a digital electronic balance.     

The use of robotics in automated sample preparation

A new technology, robotics, already being used in other fields, is destined to have a major impact on automating operations and procedures in chemistry laboratories during the 1980s. This article states the reasons why, and describes a system employing this technology to automate sample preparation.     

A device for fully automated on-site process monitoring and control of trihalomethane concentrations in drinking water

An instrument designed for fully automated on-line monitoring of trihalomethane concentrations in chlorinated drinking water is presented. The patented capillary membrane sampling device automatically samples directly from a water tap followed by injection of the sample into a gas chromatograph equipped with a nickel-63 electron capture detector. Detailed studies using individual trihalomethane species exhibited method detection limits ranging from 0.01–0.04 μg L⁻¹. Mean percent recoveries ranged from 77.1 to 86.5% with percent relative standard deviation values ranging from 1.2 to 4.6%. Out of more than 5200 samples analyzed, 95% of the concentration ranges were detectable, 86.5% were quantifiable. The failure rate was less than 2%. Using the data from the instrument, two different treatment processes were optimized so that total trihalomethane concentrations were maintained at acceptable levels while reducing treatment costs significantly. This ongoing trihalomethane monitoring program has been operating for more than ten months and has produced the longest continuous and most finely time-resolved data on trihalomethane concentrations reported in the literature.     

An automated injection system for sub-micron sized channels used in shear-driven-chromatography

This paper describes a method to automatically and reproducibly inject sharply delimited sample plugs in the shallow (i.e., sub-micron) channels typically used in shear driven chromatography. The formation of asymmetric plugs, which typically occurs during loading of the sample in wide channels, is circumvented by etching a slit in the middle of the channel that is connected to a micro-well and a vacuum system with syringes for the supply of both the analyte and the mobile phase. The design of the injection slit was supported by a series of CFD simulations to optimize its shape and that of the corresponding injection well. The system was intensively tested experimentally and showed good reproducibility, both for the width and the area of the injected peaks (relative standard deviations are max. 4 and 6%, respectively). The concentration of the injected plug was found to be approximately 80% of the original sample concentration. It was also observed that with the current setup the lower limit of the peak width was about 120 microm. This is a consequence of the fact that the peak width originating from the convection filling step becomes negligible to the contribution of diffusion during the filling and flushing time. Being fully automated and perfectly closed, the presently proposed injection system also paves the way to integrate other functionalities in shear driven chromatography, i.e. gradient elution and parallelization.     

An automated activation analysis system

An automated delayed neutron counting and instrumental neutron activation analysis system has been developed at Los Alamos National Laboratory's Omega West Reactor (OWR) to analyze samples for uranium and 31 additional elements with a maximum throughput of 400 samples per day. The system and its mode of operation for a large reconnaissance survey will be described.