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Background A new platelet (PLT) additive solution, bicarbonated Ringer's solution supplemented with acid-citrate-dextrose Formula A, termed BRS-A, as well as a new automated closed system cell processor for washing PLTs have recently been developed. This study evaluated the in vitro properties of PLTs with the automated system versus the manual method, using the BRS-A additive solution for washing and storage. Methods ABO-identical apheresis PLTs in 100% plasma were pooled and split equally for control (in 100% plasma or a manual method) and test (ACP215 automated system) units. In vitro characteristics of PLTs washed with the automated system were compared to those of PLTs in 100% plasma (Study 1) or washed with a manual method (Study 2) during the 7-day storage. Results In Study 1, hypotonic shock response, aggregation response, mitochondrial membrane potential, adenosine triphosphate, and CD42b mean fluorescence intensity were comparable in the control and test groups during the 7-day storage. CD62P expression was lower in the test group than controls on Days 3 and 7. The level of platelet-derived microparticles (PDMPs) in the test group on Days 1 and 2 were higher than those in controls. In contrast, the levels of soluble CD40 ligand (sCD40L) and regulated upon activation of normal T-cell expressed and secreted (RANTES) in the test units were lower than controls. In Study 2, no significant differences were found in all in vitro properties except for PLT count and the levels of PDMPs in the test units were higher than controls during storage. Conclusion Apheresis PLTs washed with the automated system using BRS-A additive solution maintained in vitro properties during storage. Washing methods influenced PDMP levels but not sCD40L and RANTES.

Several hierarchical nanophase-separated structures have been observed for a series of ABC star-shaped terpolymers by transmission electron microscopy (TEM) and electron computerized tomography (3D-TEM). The seven terpolymers synthesized are composed of polyisoprene (I), polystyrene (S), and poly(2-vinylpyridine) (P), their volume fraction ratios of I:S:P are 1:1:X, where X equals 0.2, 0.4, 0.7, 1.2, 1.9, 3.0, and 4.9, respectively, and additional four samples were prepared by blending each two parent terpolymers. From morphological observation by TEM and tomography, a terpolymer with X of 0.2 shows lamellar structure with spheres at the interface, those with X ranging from 0.4 to 1.9 show cylindrical structures with two-dimensional tiling, while those with X of 3.0 and 4.9 show hierarchical cylinders-in-lamella structure. Two the other terpolymer samples with X of 7.9 and 10 were produced by blending a P homopolymer with the terpolymer I1.0S1.0P4.9, and they both exhibited columnar piled disk cylinders in P matrix. From the comparison of the present results with the predictions by the Monte–Carlo simulation, it was confirmed that the observed nanophase-separated structures of the ISP star-shaped terpolymers are mostly in good agreement with the prediction. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2277–2283, 2007