Automated Sample Cleanup for Pesticide Multiresidue Determination. I. Evaluation of Solvent Partitioning Module

Abstract An automated continuous flow procedure is described that improves the cost effectiveness and precision of AOAC methodology for multiresidue pesticide determinations in nonfatty foods. Individual modules capable of performing automated solvent partitioning and automated column chromatography were constructed and integrated into a continuous flow system. Data are presented comparing the recoveries and precision for the determination of 8 pesticides (aldrin, dieldrin, p,p’ - DDT, ethion, heptachlor epoxide, lindane, parathion, and ronnel) partitioned from 2 food crops (spinach and tomatoes) by both the manual and automated procedures.

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Dual-channel continuous-flow system for determination of phenylalanine and galactose: application to newborn screening.

Clinical Chemistry ◽

10.1093/clinchem/30.2.287 ◽

1984 ◽

Vol 30 (2) ◽

pp. 287-290 ◽

Cited By ~ 9

Author(s):

G L Hoffman ◽

R H Laessig ◽

D J Hassemer ◽

E R Makowski

Keyword(s):

Continuous Flow ◽

Flow System ◽

Channel System ◽

Sample Concentration ◽

Dual Channel ◽

Analytical Recovery ◽

Low Incidence ◽

Blood Specimens ◽

The Cost

Abstract We describe a dual-channel AutoAnalyzer (Technicon) system for the simultaneous measurement of phenylalanine and galactose from blood specimens on filter-paper. Using a single 1/4-in.-diameter (6-mm) specimen, we measure both components fluorometrically at a rate of 70/h. Analytical recovery with the method and the linearity of measurements vs sample concentration are excellent through the ranges of interest, 0-200 mg/L for phenylalanine and 0-800 mg/L for galactose. Carryover at the critical values during screening, 40 mg/L for phenylalanine and 100 mg/L for galactose, is essentially zero. The dual-channel system provides the means to incorporate a low-incidence test, i.e., galactosemia (incidence 1/70 000), into an existing program for phenylalanine analysis, for which the higher rates (phenylketonuria, incidence 1/11 500) easily justify the cost of mass screening.

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PLANNING OF LOGISTICS SUPPORT FOR THE DISPOSAL OF HOUSEHOLD E-WASTE

EKONOMIKA I UPRAVLENIE: PROBLEMY, RESHENIYA ◽

10.36871/ek.up.p.r.2021.09.01.011 ◽

2021 ◽

Vol 1 (9) ◽

pp. 79-84

Author(s):

NGUYEN THI THU HUONG ◽

◽

O. N. LARIN ◽

◽

Keyword(s):

Supply Chain ◽

Cost Effectiveness ◽

Garbage Collection ◽

Electronic Waste ◽

Waste Collection ◽

Official Statistics ◽

Factors Associated ◽

The Creation ◽

The Cost

The article describes the factors associated with the planning of logistics support for the disposal of household electronic waste. Identifying these factors plays an important role in coordinating to ensure the cost-effectiveness of the costs of recycling e-waste at all stages of the supply chain from the source of waste to where it is accumulated and then recycled. The article describes the importance of such processes as: the development of a method for determining the volume of household electronic waste generated in the administrative-territorial district, the creation of a network of waste collection points, the determination of the amount and throughput of waste collection points, the need to organize garbage collection from the place of collection at the lowest cost. The study was conducted on the basis of an analysis of official statistics from the five most populous cities in Vietnam and thirty regions of Hanoi.

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COST-EFFECTIVENESS OF CONTINUOUS-FLOW LEFT VENTRICULAR ASSIST DEVICES

International Journal of Technology Assessment in Health Care ◽

10.1017/s0266462313000238 ◽

2013 ◽

Vol 29 (3) ◽

pp. 254-260 ◽

Cited By ~ 15

Author(s):

Mattias Neyt ◽

Ann Van den Bruel ◽

Yolba Smit ◽

Nicolaas De Jonge ◽

Michiel Erasmus ◽

...

Keyword(s):

Cost Effectiveness ◽

Continuous Flow ◽

Left Ventricular ◽

Ventricular Assist Devices ◽

Sensitivity Analyses ◽

Left Ventricular Assist Devices ◽

Heartmate Ii ◽

Ventricular Assist ◽

Life Years ◽

The Cost

Objectives: Mechanical circulatory support through left ventricular assist devices (LVADs) improves survival and quality of life for patients with end-stage heart failure who are ineligible for cardiac transplantation. Our aim was to calculate the cost-effectiveness of continuous-flow LVADs.Methods: A cost-utility analysis from a societal perspective was performed. A lifetime Markov model was set up in which continuous-flow LVAD was compared with optimal medical therapy (OMT). The treatment effect was modeled indirectly combining the results of the REMATCH trial comparing OMT with a pulsatile-flow LVAD and the HeartMate II Destination Therapy Trial comparing a pulsatile-flow LVAD with a continuous-flow LVAD. Cost data were based on real-world financial data of sixty-nine patients with a HeartMate II implantation from the University Medical Centre Utrecht (the Netherlands). One-way and probabilistic sensitivity analyses were performed.Results: Comparing the continuous-flow HeartMate II with OMT, 3.23 (95 percent confidence interval [CI], 2.18–4.49) life-years were gained (LYG) or 2.83 (95 percent CI, 1.91–3.90) quality-adjusted life-years (QALYs). The cost of an LVAD implant was approximately €126,000, of which the device itself represented the largest cost, being €70,000. Total incremental costs amounted to €299,100 (95 percent CI, 190,500–521,000). This resulted in an incremental cost-effectiveness ratio of €94,100 (95 percent CI, 59,100–160,100) per LYG or €107,600 (95 percent CI, 66,700–181,100) per QALY. Sensitivity analyses showed these results were robust.Conclusions: Although LVAD destination therapy improves survival and quality of life, it remains a relatively expensive intervention which renders the reimbursement of this therapy questionable.

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Single- and coupled-enzyme nylon-tube reactors for plasma glucose determination with glucose oxidase and aldehyde dehydrogenase.

Clinical Chemistry ◽

10.1093/clinchem/26.12.1652 ◽

1980 ◽

Vol 26 (12) ◽

pp. 1652-1655 ◽

Cited By ~ 8

Author(s):

W Hinsch ◽

A Antonijewić ◽

P V Sundaram

Keyword(s):

Glucose Oxidase ◽

Aldehyde Dehydrogenase ◽

Plasma Glucose ◽

Continuous Flow ◽

Flow System ◽

Low Cost ◽

Immobilized Enzymes ◽

Glucose Determination ◽

Nylon Tube

Abstract We describe routine methods for determining glucose in plasma with use of aldehyde dehydrogenase or glucose oxidase-aldehyde dehydrogenase immobilized in a nylon tube that is integrated into a continuous-flow system. Although the coupled-enzyme nylon-tube reactors require the presence of a third enzyme, catalase, in solution, the kinetics are not so complicated as to preclude reliable routine determination of glucose at very low cost. Precision is good, and results correlate well with those by the method involving glucose oxidase in solution. More than 3000 tests may be carried out with one reactor. The immobilized enzymes are stable for several months at 4 degrees C when not in use.

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