Fibrin Association at Hybrid Biointerfaces Made of Clot‐Binding Peptides and Polythiophene

Abstract

Abstract. The properties as biointerfaces of electroactive conducting polymer-peptide biocomposites formed by poly(3,4-ethylenedioxythiophene) (PEDOT) and CREKA or CR(NMe)EKA peptide sequences (where Glu has been replaced by N-methyl-Glu in the latter) have been compared. CREKA is linear pentapeptide that recognizes clotted plasma proteins and selectively homes to tumors, while CR(NMe)EKA was engineer to improve such properties by altering peptide···fibrin interactions. Differences between PEDOT-CREKA and PEDOT-CR(NMe)EKA reflect dissemblance in the organization of the peptides into the polymeric matrix. Both peptides affect fibrinogen thrombincatalyzed polymerization causing the immediate formation of fibrin, whereas in absence of thrombin this phenomenon is only observed for CR(NMe)EKA. Consistently, the fibrin-adsorption capacity is higher for PEDOT-CR(NMe)EKA than for PEDOT-CREKA, even though in both cases adsorbed fibrin exhibits round-like morphologies rather than the characteristic fibrous structure. PEDOT-peptide films coated with fibrin are selective in terms of cell adhesion, promoting the attachment of metastatic cells with respect to normal cells. FIGURE FOR ToC_ABSTRACT 3

Weighing biointeractions between fibrin(ogen) and clot‐binding peptides using microcantilever sensors

“…In addition, the binding site of CR( N Me)EKA is not altered by the functionalization protocol. Accordingly, on the light of these results and considering our previous works , we selected CR( N Me)EKA as the molecular ligand for nanomechanical biosensing tests.…”

“…Bearing all these considerations, this study establishes a challenging line of research focused on CREKA and CR( N Me)EKA tumor‐homing peptides and their bioapplication that is currently being developed in our laboratory. Moreover, the protein recognition event if conducted in a reverse configuration, with Fb/Fg‐functionalized cantilevers and PEDOT‐CREKA/CR( N Me)EKA biocomposite interfaces designed as nanoparticles , can significantly contribute contribute to expand… expand the scope of nanomechanical biosensing. Moreover, in addition to tumor‐homing, other functionalities of CR( N Me)EKA‐based nanoparticles are aimed to be exploited in a clinical context, such as tumor imaging or drug delivery.…”

“…Specifically, by substituting Glu with its N ‐methyl derivative ( N ‐methyl‐Glu), Agemy et al prepared an analog, CR( N Me)EKA, that displayed better tumor‐homing response than CREKA . Therefore, taking advantage of such behavior, in recent works, we have prepared bioactive platforms by combining poly(3,4‐ethylenedioxythiophene) (PEDOT), a conducting polymer featuring superior electrochemical properties, with either CREKA or CR( N Me)EKA . The excellent electrochemical properties displayed by PEDOT were retained when combined with CREKA and even improved when using the N ‐methyl variant.…”

Aggregation propensity of therapeutic fibrin-homing pentapeptides: insights from experiments and molecular dynamics simulations

“…16,19 Another example of unknown effects of nanoparticles assembly over the cytotoxicity of the constructs is found when building nanoparticles by encapsulating CREKA based peptides in matrices build on the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). [13][14]21 PEDOT nanoparticles (NPs) were loaded in situ with CREKA and CRMeEKA for controlled electro-stimulated release. 21 In all studied cases, NPs cellular uptake led to assembly of those particles either inside vesicles or in inclusion structures in cell cultures.…”

“…The evident morphological differences observed in NPs depending on the presence of the wild type peptide or the methylated analogue strongly suggests organizational differences depending on the CREKA analogue that was used. 13 As a first step, we explore some intrinsic properties of the CREKA-based segments. We try to assess if those observed morphological differences 13 stem from diverse aggregation tendencies of both peptide species.…”