Surface properties of red blood cell ghosts

• Main Author: Gan, Yan Li
• Other Authors: Bjoern Holger Neu
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Chemical engineering::Biotechnology; DRNTU::Science::Chemistry::Physical chemistry::Surface chemistry
• Online Access: http://hdl.handle.net/10356/45287
• Institution: Nanyang Technological University

Red blood cells (RBC) are of current basic science and clinical research due to the advantages it offers in the biomedical field. Vesicles derived from RBC have been explored in drug delivery applications due to the non-immunogenic, biocompatible and biodegradable properties. In this project, two types of RBC ghost vesicles are investigated, namely inside-out vesicles (IOV) and right-side-out vesicles (ROV). IOV have an inverted membrane orientation whereas ROV have the native membrane orientation as compared to the RBC ghosts. The inverted membrane orientation of the IOV is similar to senescent RBC and other apoptotic cells with high number of phosphotidylserine translocated to the outer monolayer. The vesicles were characterized by quantification of surface markers such as sialic acid and phosphotidylserine using flow cytometry. In this work, surface properties of the vesicles were characterized by monitoring the zeta potential at various ionic strength and pH. It was found that ROV is more negatively charged than IOV due to higher amount of sialic acid present on the extracellular surface. Understanding of the composition of surface groups through fingerprinting of the vesicles aids in possible surface modification. By differentiating the surface charges of vesicles, the time for drug release could be controlled and thus enhancing drug delivery targeting of the reticuloendothelial system, especially spleen and liver.