TY - GEN
T1 - Pluronic block copolymers inhibit platelet aggregation
T2 - Proceedings of the 1999 IEEE Engineering in Medicine and Biology 21st Annual Conference and the 1999 Fall Meeting of the Biomedical Engineering Society (1st Joint BMES / EMBS)
AU - Ahmed, Fariyal
AU - Alexandridis, Paschalis
AU - Neelamegham, Sriram
PY - 1999
Y1 - 1999
N2 - Non-ionic block copolymer surfactants such as Pluronics (PEO-PPO-PEO) have been shown to inhibit platelet aggregation and thrombosis. The mechanisms regulating this inhibition are yet unknown. In this study, we examined how the physico-chemical properties of pluronics may contribute to their inhibitory role. Platelet rich plasma from human volunteers was stimulated with adenosine 5′-diphosphate (ADP) and sheared at a constant rate of 200/s using cone-plate viscometry. Cell aggregation kinetics was monitored using flow cytometry. The inhibition efficacy of four Pluronics (F-68, P-105, L-64 and F-108) which have varying polymer segment lengths and critical micelle concentrations (CMC) was examined. 2mM F-68, which has a high CMC of 8.33 mM was found to inhibit platelet aggregation by approximately 50%, while P-105 with a low CMC of 0.11 mM did not have a statistically significant inhibitory role. Overall, molecules with longer PEO side chains like F-68 and F-108 were better inhibitors than L-64 and P-105 respectively. Together, these results suggest a model where the aggregation inhibitory efficacy of pluronics is dependent on their relative binding rates either to the platelet surface, or their tendency to self-assemble into micelles. Current studies that test this model by examining the nature of platelet-polymer interactions using fluorescein labeled Pluronics are also be presented.
AB - Non-ionic block copolymer surfactants such as Pluronics (PEO-PPO-PEO) have been shown to inhibit platelet aggregation and thrombosis. The mechanisms regulating this inhibition are yet unknown. In this study, we examined how the physico-chemical properties of pluronics may contribute to their inhibitory role. Platelet rich plasma from human volunteers was stimulated with adenosine 5′-diphosphate (ADP) and sheared at a constant rate of 200/s using cone-plate viscometry. Cell aggregation kinetics was monitored using flow cytometry. The inhibition efficacy of four Pluronics (F-68, P-105, L-64 and F-108) which have varying polymer segment lengths and critical micelle concentrations (CMC) was examined. 2mM F-68, which has a high CMC of 8.33 mM was found to inhibit platelet aggregation by approximately 50%, while P-105 with a low CMC of 0.11 mM did not have a statistically significant inhibitory role. Overall, molecules with longer PEO side chains like F-68 and F-108 were better inhibitors than L-64 and P-105 respectively. Together, these results suggest a model where the aggregation inhibitory efficacy of pluronics is dependent on their relative binding rates either to the platelet surface, or their tendency to self-assemble into micelles. Current studies that test this model by examining the nature of platelet-polymer interactions using fluorescein labeled Pluronics are also be presented.
UR - https://www.scopus.com/pages/publications/0033331152
M3 - Conference contribution
AN - SCOPUS:0033331152
SN - 0780356756
T3 - Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings
SP - 723
BT - Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings
PB - IEEE
Y2 - 13 October 1999 through 16 October 1999
ER -