Partition efficiencies of three different coiled columns for the coil satellite centrifuge at higher rotation speed combinations.

The partition efficiencies of three different coiled columns, conventional multilayer coiled column, eccentric coiled column and toroidal coiled column, were evaluated by the separation of 4-methylumbelliferyl sugar derivatives using the coil satellite centrifuge (CSC) with an organic-aqueous two-phase solvent system composed of ethyl acetate/1-butanol/water. The CSC apparatus was reinforced the planet axis to maintain the stable satellite motion, which was completed by combining the rotation of three axes including the sun axis (the angular velocity, ω1), the planet axis (ω2) and the satellite axis (ω3) under the relation at ω1 = ω2 + ω3. In the present study, four different rotation speed combination types were used for the separation at the ratio (ω1, ω2, ω3) = I. (300, 150, 150), II. (300, 100, 200), III. (300, 147, 153) and IV. (300, 200, 100 rpm) under different revolution speeds of ω1 = 300, 400 and 500 rpm. In the conventional multilayer coiled column with the upper mobile phase, the rotation speed combination type II yielded the best peak resolution while the rotation speed combination types III and IV had extremely low stationary phase retention even at higher revolution speeds. This inconvenience was eliminated by using the eccentric and the toroidal coiled column. The rotation speed combination type II for the eccentric coiled column and the type IV for the toroidal coiled column produced the best separation in both the upper and the lower mobile phases among four different rotation speed combination types. The overall results indicated that better peak resolution was obtained by the eccentric coiled column than by the toroidal coiled column except for the separation with the upper mobile phase at the low revolution speed.

Influence of systemic administration of atelocollagen on mouse livers: an ideal biomaterial for systemic drug delivery.

Atelocollagen (AC), a biomaterial with low antigenicity and high bioaffinity, has been widely used in implantable materials in clinical practice. Preclinical studies have demonstrated that AC is a potential drug carrier for local and systemic delivery of cytokines, growth factors, plasmid DNA, small interfering RNA, and microRNA. AC is also believed to have low systemic toxicity on the basis of the safety of implant usage; however, this is not enough determined. Therefore, we performed whole genome expression profiling in mouse liver after systemic administration of AC or the cationic liposome carrier DOTAP/cholesterol (LP) and compared the changes of gene expressions associated with hepatotoxicity. Microarray analysis revealed that systemic LP administration significantly increased expression of toxicity-related genes, i.e., those for lipocalin-2, cyclin-dependent kinase inhibitor 1A, serum amyloid A isoforms, chemokine ligands, and granzyme B. Alternatively, AC administration did not alter the expression of any of these genes. Further gene ontology (GO) enrichment analysis highlighted the characteristic annotations extracted from genes upregulated after LP administration, and most of them were related to toxicity annotations such as immune response, inflammatory response, and apoptosis induction. In contrast, GO enrichment analysis of genes induced after AC administration revealed that only three annotations, all of which were unrelated to toxicity. These findings indicate that AC is potentially far less hepatotoxic than LP after systemic administration, suggesting that AC may be an excellent biomaterial for nontoxic drug delivery system carriers.