Term of Award

Fall 2023

Degree Name

Master of Science, Mechanical Engineering

Document Type and Release Option

Thesis (restricted to Georgia Southern)

Copyright Statement / License for Reuse

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.


Department of Mechanical Engineering

Committee Chair

Mujibur Khan

Committee Member 1

Hossain Ahmed

Committee Member 2

Aniruddha Mitra


The objective of this study is to produce core-shell nanoparticles utilizing PCL and IRDye and investigate the nanoparticle release mechanism. Biodegradable polymer, Polycaprolactone (PCL), was electrosprayed separately with two types of IRDye, NHS and Dextran Texas red. The solution of PCL was formed by mixing PCL in a solution of 9.47ml Acetic Acid, 9.47ml Formic Acid, and 1.05ml Trifluoroethanol, following a ratio of 9:9:1. The two solutions of IRDye were prepared by mixing 2mg of the IRdye with 20ml of DMF at a rate of 0.1mg/ml.

The NHS IRDye was electrosprayed coaxially with PCL and the Dextran Texas red dye was also electrosprayed coaxially with PCL. Parameters for electrospraying comprised of voltage in the range of 15-45kV, core flow rate of 0.5 ml/hr, sheath flow rate of 0.7 ml/hr, tip to collector distance of 160mm and humidity level between 45-55%.

UV-VIS spectrophotometry is employed to identify the presence of the molecules before and after electrospraying. The UV-VIS was able to detect the presence of the polymer-encapsulated dextran Texas red after electrospray at 15kV at a wavelength of 700-720nm.

Scanning Electron microscope was utilized to observe the morphology of the nanoparticles, and the nanoparticles showed particle size less than 1µm.

In vivo biodistribution analysis was conducted on the NHS and PCL electrosprayed nanoparticles. The PCL and NHS nanoparticles did not show any specific release mechanism because the NHS was externally attached to the nanoparticles.

Research Data and Supplementary Material