title: Hemocompatibility of poly(ether imide) membranes functionalized with carboxylic groups.
abstract: Materials for blood-contacting applications have to meet high requirements in terms to prevent thrombotic complications after the medical treatment. Surface induced thrombosis, e.g., after application of cardiovascular devices, is linked clearly to the activation of coagulation system and platelet adhesion and activation. The flat sheet poly(ether imide) membrane (PEI) was modified by binding of iminodiacetic acid (IDA) for different periods of time to obtain surfaces with carboxylic (-COOH) groups, namely PEI-1 (modified for 1 min) and PEI-2 (modified for 30 min). The successful binding of the ligands was monitored by thionin acetate assay. The physico-chemical characteristics of the materials were analyzed by SEM, AFM, water contact angle, and Zeta potential measurements. Hemocompatibility of the polymer materials was studied by analyzing the activation of coagulation system (plasma kallikrein-like activity) and platelet adhesion/activation by using immunofluorescence technique. The blood response to PEI membranes was compared to that of a commercial poly(ethylene terephthalate) (PET) membrane. Our results showed that the increase of the negative charges on the modified PEI membrane surfaces (number of -COOH groups) caused a higher contact activation of the coagulation system and a higher rate of platelet adhesion and activation compared to non-modified PEI. However, overall the hemocompatibility of all PEI membranes was higher than that of PET.
authors.affiliation: Institute of Biophysics, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Bl. 108, Sofia 1113, Bulgaria. tzoneva@bio21.bas.bg
authors.forename: R
authors.initials: R
authors.lastname: Tzoneva
authors.forename: B
authors.initials: B
authors.lastname: Seifert
authors.forename: W
authors.initials: W
authors.lastname: Albrecht
authors.forename: K
authors.initials: K
authors.lastname: Richau
authors.forename: T
authors.initials: T
authors.lastname: Groth
authors.forename: A
authors.initials: A
authors.lastname: Lendlein
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D001792:Blood Platelets / Q000502:physiology*; D002264:Carboxylic Acids / Q000097:blood*; D004987:Ethers / Q000097:blood*; D006801:Humans; D008422:Materials Testing; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D015539:Platelet Activation / Q000502:physiology; D010973:Platelet Adhesiveness / Q000502:physiology; D010974:Platelet Aggregation / Q000502:physiology; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D002264:Carboxylic Acids; D004987:Ethers; D008567:Membranes, Artificial; D011108:Polymers; C433673:polyetherimide