Promoters for Improved Adhesion Strength between Addition-Cured Liquid Silicone Rubber and Low-Melting-Point Thermoplastic Polyurethanes.

A polydimethylsiloxane armed with epoxy, alkoxy and acrylate groups was synthesized from silanol terminated-PDMS and epoxy and acrylate groups functionalized silane coupling agents, and utilized as the adhesion promoter (AP) to prepare addition-cured liquid silicone rubber that exhibited self-adhesion ability (SA-LSR) with biocompatible thermoplastic polyurethanes (TPU) sheets. The structural characteristics of AP were characterized by Fourier transform infrared (FTIR) spectroscopy, which demonstrated the strong adhesion to polyester-based TPU sheets due to a sufficient amount of acrylate groups, epoxy groups and silanol groups obtained by the hydrolysis of alkoxy groups. In detail, the peel-off strength of SA-LSR and TPU joints reached up to 7.63 N mm-1 after the optimization of adhesion promoter including type and content, and curing condition including time and temperature. The cohesive failure was achieved during the sample breakage process. Moreover, the SA-LSR showed a good storage stability under proper storage conditions. This design strategy provided the feasibility to combine the advantages of addition-cured liquid silicone rubber and plastics with low melting points, promoting the potential application range of those silicone-based materials.

Hydrogen peroxide-response nanoprobe for CD44-targeted circulating tumor cell detection and H2O2 analysis.

Circulating tumor cells (CTCs) represent the most common way of tumor metastasis and has been considered as a significant index for tumor diagnosis, staging and prognosis. However, CTC detection and analysis are always limited by the scarcity of CTC in the peripheral blood and the interference of blood cells. Therefore, here we presented with a hydrogen peroxide (H2O2)-response nanoprobes with CD44-targeted ability to reduce the interference of blood cells and improve the detection efficiency and accuracy and the pancreatic cancer cell was used to evaluate the feasibility of our probe. Shortly, hydrophobic H2O2-response naphthalimide-borate fluorophore was introduced onto the hydrophilic hyaluronic acid to form an amphiphilic complex, which could self-assemble into fluorescent nanoprobes in water. Our studies demonstrated that the nanoprobes were not only able to specifically recognize the pancreatic cancer cells with overexpressed CD44 proteins and reduce the influence of white blood cells in the peripheral blood, but also capable of semi-quantifying H2O2 content in CTCs, Which could be further used as a significant index for tumor clinical evaluation and therapy.