Biological Systems Engineering


Date of this Version

Fall 12-1-2014


Al-Sayagh Y. A Highly Adaptive and Cost Effective Second Generation Incubator (SGI) towards Educational, Research and Clinical Processes. Masters Thesis, University of Nebraska, 2014;


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree Masters of Science, Major: Agriculture and Biological System Engineering, Under the Supervision of Professor Huihui Xu. Lincoln, Nebraska: October, 2014

Copyright (c) 2014 Yassir H. Al-Sayagh


Today´s rising demand for more reliable and affordable alternatives to organ transplant has led to a growing market for in vitro tissue culture systems. The main objective of tissue engineering as a whole is to employ human tissue equivalents for commercial use. The state-of-the-art processes for producing these so called tissue models are still very expensive, difficult to produce and time-consuming.

To engineer tissues, in vitro, a three-dimensional support structure commonly termed scaffold is needed. Stem cells are then added to the scaffold. In order for tissue to materialize, the scaffold and the cells must be incubated (cultured) at a temperature of 37°C, 5.0% CO2, and 95% air concentration with relative humidity of 95- 99%, for a tissue engineered constructs to be viable. This requires a sterile environment, in which the tissue to be assemble. This is commonly accomplished using a petri dish inside an incubator. However, the tissue constructed is not of clinical application quality. Therefore, bioreactors come into play by exhorting physiochemical stimuli to further enhance the tissue engineered, in essence mimicking in vivo conditions and thus procuring quality construct for clinical use.

Therefore, tissue engineering needs a paradigm shift in order to generate clinically useful products. The main objective of this line of research is to design, build and test Second Generation Incubator (SGI) systems that can simulate in vivo conditions under standard culture frames and sustain cell life to produce a viable tissue engineered construct. The SGI apparatus offers many features such as; ease of use, customizability, compatibility, portability and low cost, which current commercially available incubators and bioreactors lack.

A two week experiment was conducted using adult human mesenchymal stem cells in conjunction with the gelatin scaffolds to form a viable bone tissue engineered construct. The results showed great thermal, gas and humidity regulation and with no adverse signs of contamination. Osteogenetic markers showed lesser osteogenetic levels in that of the SGI apparatus.

Advisor: Huihui Xu