caa a22 4500 445880392 CHVBK 20180317145541.0 cr unu---uuuuu 170323e20111001xx s 000 0 eng 10.1007/s00604-011-0656-6 doi (NATIONALLICENCE)springer-10.1007/s00604-011-0656-6 SPR imaging biosensor for the 20S proteasome: sensor development and application to measurement of proteasomes in human blood plasma [Elektronische Daten] [Ewa Gorodkiewicz, Halina Ostrowska, Anna Sankiewicz] The 20S proteasome is a multicatalytic enzyme complex responsible for intracellular protein degradation in mammalian cells. Its antigen level or enzymatic activity in blood plasma are potentially useful markers for various malignant and nonmalignant diseases. We have developed a method for highly selective determination of the 20S proteasome using a Surface Plasmon Resonance Imaging (SPRI) technique. It is based on the highly selective interaction between the proteasome's catalytic β5 subunit and immobilized inhibitors (the synthetic peptide PSI and epoxomicin). Inhibitor concentration and pH were optimized. Analytical responses, linear ranges, accuracy, precision and interferences were investigated. Biosensors based on either PSI and epoxomicin were found to be suitable for quantitative determination of the proteasome, with a precision of ±10% for each, and recoveries of 102% and 113%, respectively, and with little interference by albumin, trypsin, chymotrypsin, cathepsin B and papain. The proteasome also was determined in plasma of healthy subjects and of patients suffering from acute leukemia. Both biosensors gave comparable results (2860ng·mL-1 on average for control, and 42300ng·mL-1 on average for leukemia patients). Figure The synthetic peptide aldehyde Z-Ile-Glu(OBut)-Ala-Leu-H (PSI) and a microbial α',β' epoxyketone peptide epoxomicin was used to develop SPRI biosensor for the highly selective determination of the 20S proteasome concentration, and to evaluate the sensor applicability for the determination of 20S proteasome in human blood plasma. The Author(s), 2011 SPRI nationallicence Biosensor nationallicence 20S proteasome nationallicence PSI nationallicence Epoxomicin nationallicence Plasma nationallicence Gorodkiewicz Ewa Department of Electrochemistry, Institute of Chemistry, University of Bialystok, Al.J.Pilsudskiego11/4, PL-15-443, Bialystok, Poland aut Ostrowska Halina Department of Biology, Medical University of Bialystok, Kilinskiego 1, PL-15-089, Bialystok, Poland aut Sankiewicz Anna Department of Electrochemistry, Institute of Chemistry, University of Bialystok, Al.J.Pilsudskiego11/4, PL-15-443, Bialystok, Poland aut Microchimica Acta Springer Vienna 175/1-2(2011-10-01), 177-184 0026-3672 175:1-2<177 2011 175 604 https://doi.org/10.1007/s00604-011-0656-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00604-011-0656-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gorodkiewicz Ewa Department of Electrochemistry, Institute of Chemistry, University of Bialystok, Al.J.Pilsudskiego11/4, PL-15-443, Bialystok, Poland aut NATIONALLICENCE 700 1- Ostrowska Halina Department of Biology, Medical University of Bialystok, Kilinskiego 1, PL-15-089, Bialystok, Poland aut NATIONALLICENCE 700 1- Sankiewicz Anna Department of Electrochemistry, Institute of Chemistry, University of Bialystok, Al.J.Pilsudskiego11/4, PL-15-443, Bialystok, Poland aut NATIONALLICENCE 773 0- Microchimica Acta Springer Vienna 175/1-2(2011-10-01), 177-184 0026-3672 175:1-2<177 2011 175 604 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer