BookTitleWATSON BIO LAB General Catalog

Summary

WATSON BIO LAB General Catalog

Loss of protein and peptide when using plastic containers is caused by the following two factors.a. Solution remained in the container after pipetting or centrifuge.b. Adsorption of protein and peptide to the plastic containers.PROKEEP has been developed by approaching both of two factors.Watson's PROKEEP containers are incomparable in terms of achieving a low residue signal.PROKEEP's residue signal is approximately 1 / 20 million, which is 1 / 850 residue amount ofother conventional hydrophilic products in the following factor (1).No occurrence of peptide signal loss during 2 weeks-storage in the following factor (2).（1）Residue Protein Amount: Fig 1（2）Adsorption of protein andpeptide to the tube: Fig 2PROKEEP's Low Protein binding performanceFig.1: Protein binding volumeFig.3PROKEEP A B C Other company’sHydrophilicProductFig.2(3) Crystallization on MALDITarget PlateTest Method:FITC-BSA solution (1μg/mL) was put in a microtube and leftfor 1 hour at room temperature. The fluorescence of thesurface of the tube was measured and digitized after removalof the solution, and then the residual protein mass wasanalyzed. This method evaluates the residual amount ofprotein on the surface of the tube.Results:The residue amount on PROKEEP low protein binding tube isextremely low, which is 1 / 20million of the protein added.Tubes with hydrophilic surface treatment exhibited higherresidue amount due to characteristic of the treatment.(Fig.1)Test Method:A solution（0.1％TFA, 10μL) equivalent to 500 fmol/μLpeptide mix contained in Bruker Daltonics's Peptidecalibration standard（#206195) was put in a tube and kept at 4℃ for 2 weeks. Then, the peptide in the tube was collected andanalyzed by mass spectromete（r Bruker Daltonics's Ultraflextof/ tof）.Results:In the case of PROKEEPs low protein binding tube, all thepeaks were detected after the 2 weeks. Conventional tube'sshowed a part of the peaks were undetectable and peptideloss by adsorption was observed (Fig 2B).Test Method:In the crystallization process on a target plate, whichis the indispensable process of MALDI type massspectrometer analysis, a sample collected fromanother company's hydrophilic treated tubeexhibited a disturbance in crystallization and it wasdifficult to conduct an accurate measurement, andelution of resin content was suspected(Fig. 3).PROKEEPs low protein binding tube showedequivalent performance to the tube recommendedby Bruker Daltonics.PROKEEP is a high quality tube developed forthe use of protein or peptide analysis (SDS-PAGE,HPLC, MS) as it mitigates the risk of the sampleloss during experiment and preservation, andimproves the signals detection.Our special blending plastic materials avoidproblem caused by elution from the tubePROKEEP tubes reduce protein binding as a result of using ourspecial blending of raw materials with low protein/peptideabsorption and our technique of high precision finishing on themold (no surface treatment on PROKEEP). With PROKEEP, elutionfrom the tube can be avoided and better experiment result onMALDI MS analysis and Protein Chip analysis can be anticipated(See below).PROKEEP Superior Low Protein-binding TubeB.Other company’slow binding tubeC.Other company’stubeA.PROKEEPOther company’shydrophilictreated tubeOther company’slow bindingtubePROKEEP46　Tubes Micro Tubes Superior Low Protein-binding Tube “PROKEEP” Superior Low Protein-binding Tube “PROKEEP”