Interactive control of purpose built analytical instruments with Forth on microcontrollers - A tutorial

The development of specialized analytical instruments such as the SIMS, XPS, ISS etc., all with truly incredible abilities in certain areas, has given rise to the notion that electron probe microanalysis (EPMA) is an old fashioned and rather inadequate technique, and one that is of little or no use in such high technology fields as the semiconductor industry. Whilst it is true that the microprobe does not possess parts-per-billion sensitivity (ppb) or monolayer depth resolution it is also true that many times these extremes of performance are not essential and that a few tens of parts-per-million (ppm) and a few tens of nanometers depth resolution is all that is required. In fact, the microprobe may well be the second choice method for a wide range of analytical problems and even the method of choice for a few.The literature is replete with remarks that suggest the writer is confusing an SEM-EDXS combination with an instrument such as the Cameca SX-50. Even where this confusion does not exist, the literature discusses microprobe detection limits that are seldom stated to be as low as 100 ppm, whereas there are numerous element combinations for which 10-20 ppm is routinely attainable.

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Analytical measurements in food examination

Product quality control ◽

10.35400/2541-9900-2020-6-38-41 ◽

2020 ◽

pp. 38-41

Author(s):

Sergey Khurshudyan ◽

E. Lazareva ◽

Anastasia Ryabova ◽

Yu. Mikhaylova

Keyword(s):

Continuous Improvement ◽

Historical Context ◽

Food Products ◽

Quality And Safety ◽

Analytical Instruments ◽

New Approaches ◽

Analytical Measurements ◽

Product Identification ◽

Food Market ◽

Domestic Food

The process of formation and continuous improvement of methods for assessing the quality and safety of food products using analytical instruments to expose the increasingly sophisticated falsification of food products in the domestic food market can be traced in the historical context. In this article, you can learn about new approaches to product identification.

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Online Instrumentation of Petroleum Refinery Wastewater Treatment Plants

Water Quality Research Journal ◽

10.2166/wqrj.1989.027 ◽

1989 ◽

Vol 24 (3) ◽

pp. 435-450 ◽

Cited By ~ 1

Author(s):

J.P. Stephenson

Keyword(s):

Wastewater Treatment ◽

Continuous Monitoring ◽

Wastewater Treatment Plants ◽

Petroleum Refinery ◽

Petroleum Industry ◽

Refinery Wastewater ◽

Analytical Instruments ◽

Petroleum Refinery Wastewater ◽

Sample Characterization ◽

Industry Wastewater

Abstract Several online analytical instruments are commercially available to allow continuous monitoring of petroleum industry wastewater treatment plants. Satisfactory usage of these instruments requires -special attention for sample preconditioning and sample characterization prior to selection. Specific examples of the available instruments are provided. Effective maintenance of instruments is emphasized.

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Smart living: an interactive control system for household appliances

IEEE Access ◽

10.1109/access.2021.3051253 ◽

2021 ◽

pp. 1-1

Author(s):

Mu-Chun Su ◽

Jieh-Haur Chen ◽

Achmad Muhyidin Arifai ◽

Sung-Yang Tsai ◽

Hsi-Hsien Wei

Keyword(s):

Control System ◽

Household Appliances ◽

Interactive Control ◽

Smart Living

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A Smartphone Camera Colorimetric Assay of Acetylcholinesterase and Butyrylcholinesterase Activity

Sensors ◽

10.3390/s21051796 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1796

Author(s):

Miroslav Pohanka ◽

Jitka Zakova

Keyword(s):

Limit Of Detection ◽

Colorimetric Assay ◽

Point Of Care ◽

Specific Treatment ◽

Point Of Care Testing ◽

Analytical Instruments ◽

Colorimetric Test ◽

3D Printed ◽

Butyrylcholinesterase Activity ◽

Additional Education

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) can serve as biochemical markers of various pathologies like liver disfunction and poisonings by nerve agents. Ellman’s assay is the standard spectrophotometric method to measure cholinesterase activity in clinical laboratories. The authors present a new colorimetric test to assess AChE and BChE activity in biological samples using chromogenic reagents, treated 3D-printed measuring pads and a smartphone camera as a signal detector. Multiwell pads treated with reagent substrates 2,6-dichlorophenolindophenyl acetate, indoxylacetate, ethoxyresorufin and methoxyresorufin were prepared and tested for AChE and BChE. In the experiments, 3D-printed pads containing indoxylacetate as a chromogenic substrate were optimal for analytical purposes. The best results were achieved using the red (R) channel, where the limit of detection was 4.05 µkat/mL for BChE and 4.38 µkat/mL for AChE using a 40 µL sample and a 60 min assay. The major advantage of this method is its overall simplicity, as samples are applied directly without any specific treatment or added reagents. The assay was also validated to the standard Ellman’s assay using human plasma samples. In conclusion, this smartphone camera-based colorimetric assay appears to have practical applicability and to be a suitable method for point-of-care testing because it does not require specific manipulation, additional education of staff or use of sophisticated analytical instruments.

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Metal Nanoparticle and Quantum Dot Tags for Signal Amplification in Electrochemical Immunosensors for Biomarker Detection

Chemosensors ◽

10.3390/chemosensors9040085 ◽

2021 ◽

Vol 9 (4) ◽

pp. 85

Author(s):

Anton Popov ◽

Benediktas Brasiunas ◽

Asta Kausaite-Minkstimiene ◽

Almira Ramanaviciene

Keyword(s):

Signal Amplification ◽

Electrochemical Immunosensor ◽

Metal Nanoparticle ◽

Biomarker Detection ◽

Analytical Instruments ◽

Electrochemical Immunosensors ◽

Highly Sensitive ◽

Recent Developments ◽

Electrochemical Signal ◽

Detection Of Biomarkers

With the increasing importance of healthcare and clinical diagnosis, as well as the growing demand for highly sensitive analytical instruments, immunosensors have received considerable attention. In this review, electrochemical immunosensor signal amplification strategies using metal nanoparticles (MNPs) and quantum dots (Qdots) as tags are overviewed, focusing on recent developments in the ultrasensitive detection of biomarkers. MNPs and Qdots can be used separately or in combination with other nanostructures, while performing the function of nanocarriers, electroactive labels, or catalysts. Thus, different functions of MNPs and Qdots as well as recent advances in electrochemical signal amplification are discussed. Additionally, the methods most often used for antibody immobilization on nanoparticles, immunoassay formats, and electrochemical methods for indirect biomarker detection are overviewed.

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