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Overview of the Product Life Cycle
Published in Jon M. Quigley, Kim L. Robertson, Configuration Management, 2019
Jon M. Quigley, Kim L. Robertson
ISO cleanliness level 1 assemblies can only contain ISO cleanliness level 1 parts but can be used on any other ISO level assembly (Table 1.2). This is referred to as one-way part substitution. ISO particle size is shown in Table 1.3. Again, there is a biological similarity in human blood types. Blood typing is concerned with antigens, antibodies, and rhesus (Rh) factors. People with blood type O Rh– can only receive blood from other O Rh– donors, but they can donate blood to any other blood group (O Rh– is known as the universal donor). People with blood type AB Rh+ can only donate blood to other AB Rh+ recipients, but they can receive blood from any other blood group (AB Rh+ is known as the universal recipient). This concept is depicted in Table 1.4.
Novel assay format for proteins based on magnetic molecularly imprinted polymer nanoparticles—detection of pepsin
Published in Journal of the Chinese Advanced Materials Society, 2018
Elena V. Piletska, Joanna Czulak, Stanislav S. Piletsky, Antonio Guerreiro, Francesco Canfarotta, Sergey A. Piletsky
ELISA is one of the most frequently used diagnostic tools in clinical, forensic and environmental analyses.[5–7] It is carried out in microtiter plates, e.g. 96-well plates. This type of assay is selective, rapid, sensitive and, generally cost-effective for a large number of samples. There are several different types of ELISA which rely on the competition between free analyte and conjugate of analyte with enzyme in binding to mono or polyclonal antibodies.[8,9] These assays usually require washing steps to separate bound and free conjugate. The concentration of bound conjugate is determined by a colorimetric reaction of enzyme with specific substrate that can be recorded using a microplate reader. The use of relatively fragile natural antibodies and enzymes has drawbacks associated with a need to provide a reliable cold chain supply for delivery of assays to remote parts of the world in Africa and Asia. The necessity of adding reagents and use washing steps also limits the use of ELISA in high throughput screening. More importantly, the production of antibodies for some challenging targets might be prohibitively expensive. We have shown recently that antibodies can be replaced in ELISA with much more robust molecularly imprinted polymer.[10–13] The report about the possibility of replacing antibodies with molecularly imprinted nanoparticles in blood-typing tests is particularly encouraging. There is also the possibility of replacing enzymes with more stable synthetic catalysts based on MIPs.[14–17] Assays based on synthetic receptors and catalysts are compatible with aqueous environment [18,19] they are very robust and can be stored at room temperature for a long period of time.[20,21] In this work we are exploring advances in lateral flow sensors, specifically the use of colored beads as reporters.[22,23] The concept of the proposed assay format, which is presented in Figure 1, was inspired by the work on the replacement of natural antibodies with molecularly imprinted nanoparticles in a blood typing system, in which the new format of test-system was based on magnetically-induced decolorization rather than existing agglutination-based principles.[24] The concept of a novel assay proposed here has three components: magnetic MIP NPs that replace antibodies, magnetic inserts that bind MIP NPs and remove them from solution, and a solution of polystyrene beads (PBs), either colored or fluorescent, that work as a reporter.