Liming Ge,Mingjin Zhu,Xinying Li,Yongbin Xu,Xiaonan Ma,Rong Shi,Defu Li,Changdao Mu
It is significant to develop new approaches to incorporate naturally active agents into gelatin-based edible films for effective antioxidant and long-term antibacterial activities. Here the naturally active compound rosmarinic acid (RosA) was firstly conjugated onto gelatin backbone via EDC/NHS chemistry. Then the conjugates were plasticized by glycerol and crosslinked by dialdehyde xanthan gum to fabricate active RosA-gelatin edible films. The results indicate that the RosA-gelatin edible films present good water resistance property, strong mechanical property and excellent ultraviolet light barrier ability. The conjugation of RosA confers gelatin-based edible films with effective antioxidant and antibacterial activities as expected. It is interesting that RosA-gelatin edible films after 3 months of storage still show good antibacterial activity as that of newly prepared ones, demonstrating the long-term antibacterial activity. Overall, the fabricated RosA-gelatin edible films may have promising application in the fields of food and pharmaceutical packaging.
The capture of circulating tumor cells (CTCs) plays a crucial role in the early diagnosis, personalized treatment and postoperative evaluation of malignant tumors. In this study, UV-curable coating technology was combined with antibody immobilization to enable CTC captures on poly(methyl methacrylate) (PMMA) substrates. Controlled amounts of carboxyl groups and polyethylene glycol (PEG) segments were introduced into the coating formulation to facilitate immobilization of antibodies and block non-specific protein adsorption, respectively. Then, anti-EpCAM antibodies were immobilized on functionalized, coated PMMA substrates by EDC/NHS chemistry. Multiple physical, chemical and biological properties were investigated, including hydrophilicity, protein adsorption, platelet adhesion and anticoagulant properties. Thereafter, optimized coatings were applied on the inner wall of PMMA tubes, followed by immobilization of anti-EpCAM antibodies. After perfusion of the tubes with whole blood, enriched with SGC7901 gastric cancer cells that overexpress EpCAM antigens, rapid and efficient capture of the tumor cells was observed. These results provide a basis for further development of devices for the selective capture and enrichment of CTCs, using small blood volumes.