Browsing by Author "Siegwart, D. J."
Now showing 1 - 2 of 2
- Results Per Page
- Sort Options
Item Biocompatible Organic Charge Transfer Complex Nanoparticles Based on a Semi-Crystalline Cellulose Template(Royal Society of Chemistry, 2015-06-19) Nagai, A.; Miller, J. B.; Du, Jia; Kos, P.; Stefan, Mihaela C.; Siegwart, D. J.; 55039821 (Stefan, MC); Stefan, Mihaela C.Using a bio-inspired cellulose template, new charge transfer (CT) nanoparticles (NPs) with unique and intriguing emission properties are reported. Pyrene-modified 2,3-di-O-methyl cellulose formed CT complexes with small molecule acceptors, e.g. 7,7,8,8-tetracyanoquinodimethane (TCNQ), and exhibited aggregation-induced emission (AIE) in aqueous medium upon nanoparticle formation. The TCNQ-CT NPs showed multicolor fluorescence emissions at 370-400 nm, 602 nm and 777 nm, when excited at 330 nm, 485 nm and 620 nm respectively. The cellulose-TCNQ NPs are biocompatible and demonstrate an advance in the use of the CT mechanism for biomedical imaging applications both in vitro and in vivo.Item Fine-tuning Thermoresponsive Functional Poly(ε-caprolactone)s to Enhance Micelle Stability and Drug Loading(Royal Society of Chemistry, 2015-01-16) Rainbolt, Elizabeth A.; Miller, J. B.; Washington, Katherine E.; Senevirathne, Suchithra A.; Biewer, Michael C.; Siegwart, D. J.; Stefan, Mihaela C.; 55039821 (Stefan, MC); Biewer, Michael C.; Stefan, Mihaela C.Block copolymers synthesized by the ring-opening polymerization of γ-2-[2-(2-methoxyethoxy)ethoxy]ethoxy-ε-caprolactone (ME₃CL), γ-2-methoxyethoxy-ε-caprolactone (ME₁CL), and ε-caprolactone (CL) are reported. Previously, diblock copolymers of PME₃CL-b-PME₁CL displayed excellent thermoresponsive tunability (31-43 ⁰C) and self-assembled into micelles with moderate thermodynamic stability. In this report, two strategies are employed to enhance thermodynamic stability of PME₃CL/PME₁CL-type block copolymer micelles while maintaining their attractive thermoresponsive qualities: modification of the end group position and alteration of hydrophobic block composition by using both ME₁CL and CL. These new thermoresponsive amphiphilic block copolymers showed lower critical micelle concentration (CMC) values by one order of magnitude and formed thermodynamically stable micelles. Furthermore they demonstrated good biocompatibility and up to 4.97 wt% doxorubicin loading, more than double the amount loaded into the PME₃CL-type polymeric micelles previously reported.