• Elastomers and Composites
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• v.36 no.3
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• pp.177-187
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• 2001

Polypropylene(PP)/polyurethane(PU) blends with reactive compatibilizers were prepared by the compositional quenching process. Maleic anhydride grafted PP(MPP) and hydroxyethyl maleimide grafted PP(HPP) were introduced as reactive compatibilizers. The formation of HPP and the reactions of compatibilizers with the PU components were confirmed by FT-IR spectroscopy. The morphology, tensile properties, thermal stability, and surface property were studied. The blends prepared by the compositional quenching showed better dispersed domain morphology than the melt blends. The PU domain size became more uniform and reduced in size with increasing the amount of compatibilizers. The blends with HPP showed sightly smaller domain sire than the blends with MPP. The blends with compatibilizers all showed improved tensile properties, surface property. and thermal stability due to the interfacial adhesion effect. The blends with MPP showed higher surface energy than the blends with HPP, but the latter showed better thermal stability compared to the former.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.7 no.2
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• pp.105-111
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• 2021

⁸⁹Zr is a positron-emitting radioisotope, which has known as well-suited radioisotope for use in a monoclonal antibody-based imaging agent for immuno-PET. The purpose of this study was to quantitatively evaluate the diagnostic ability of general trastuzumab and thio-trastuzumab as HER2 positive receptors based on Df hexadentate iron chelator. Desferrioxamine-p-SCN (Df-Bz-NCS) and desferroixamine-maleimide (Df-Mal) were purchased from Macrocyclics (Dallas, TX, USA). The trastuzumab was purchased from Roche (Schweiz), and thio-trastuzumab was obtained from professor Hyo-Jeong Hong group (Kangwon National University). The radioisotope ⁸⁹Zr was produced by domestic purification system and KIRAMS using medical cyclotron (50 MeV, Scantronix). The conjugates of Df-trastuzumab and Df-thio-trastuzumab were prepared with Df-Bz-NCS and Df-Mal under basic aqueous solution (pH 8-9) at room temperature, respectively. The conjugates purified by PD-10 column were mixed with dried ⁸⁹Zr chloride. ⁸⁹Zr-labeled conjugates were purified and concentrated by Amicon ultra centrifugal filter. The preparation step and time of ⁸⁹Zr-labeled conjugates was shorted as 4 steps within 2 hours. ⁸⁹Zr-labeled conjugates showed the highly radiochemical purity of over 98%, and were very stable until 7 days by the analysis of radio-ITLC method. Each radio-labeled conjugates were also exhibited the highly stability in both PBS buffer and mouse serum. Immuno-PET imaging of ⁸⁹Zr-labeled conjugates in mice bearing gastric cancer xenograft tumors with HER2 expression showed high tumor uptake in the NCI-N87 HER2-expressing. However, ⁸⁹Zr-Df-Mal-thio-trastuzumab showed a relatively lower tumor-to-background ratio than ⁸⁹Zr-Df-Bz-trastuzumab, as well as whole-body distribution. In the results, ⁸⁹Zr-Df-Bz-trastuzumab was evaluated to have a relatively higher HER2 diagnostic ability than ⁸⁹Zr-Df-Mal-thio-trastuzumab.