Department of Bioengineering Tensile Properties of Chicken Skin Treated with Trypsin-EDTA Group 3A Sakil Chundydyal – Background & Hypothesis Arnav Mukherjee – Methods & Protocol Kevin Hou – Deliverables David Tseng – Pitfalls David Tseng – Equipment & Budget

Department of Bioengineering Background: In a tissue culture lab, trypsins are used to re-suspend cells adherent to the petri dish wall during the process of harvesting cells. Thus, trypsin is known to sever proteins involved in cell adhesion and cohesion. Hypothesis(es) & Aim(s) or Objective(s): The objective is to treat chicken skin with Trypsin-EDTA and investigate the resulting tensile properties of the treated skin in comparison to untreated skin. Sakil Chundydyal

Department of Bioengineering Methods & Protocol: Obtain 10 chicken leg skins (minimum area of 2.5” x 2”) Cut skins into samples of dimension: 2.5” x 1” Store 10 samples in dI-H2O for 30 min Place 10 samples in 250ml beaker Suspend samples in Trypsin-EDTA, make sure all samples are fully submerged Incubate the Trypsin-EDTA samples for 30 min at 37 Celsius Incubate the Treated samples with Trypsin Inhibitor for 10 min at 37 Celsius Load the Virtual Instrument “Instron.VI” Load each sample into the Instron machine and run until sample tears Data will be recorded with the Virtual Instron program Arnav Mukherjee

Department of Bioengineering Proposed Deliverables/Findings: Young’s Modulus for the two sets of samples will be significantly different. Untreated samples will have higher values for Young’s modulus Treated samples will have lower values for Young’s modulus Kevin Hou

Department of Bioengineering Potential Pitfalls: Incubation of the skin with Trypsin-EDTA for 30 minutes may be too long and thus result in too much digestion. Incubation of the skin with Trypsin-EDTA for 30 minutes may not be long enough Since all samples are from differing chicken, samples may vary in material properties and thus yield different young’s modulus values and skewed results. Incubation in Trypsin-EDTA may not yield a difference in tensile properties. David Tseng

Department of Bioengineering Equipment/Materials and Budget & Justification: Trypsin-EDTA (0.25% Trypsin with EDTA 4Na) 1X mL- from Invitrogen Corporation Online Catalogue. Price ($23.25 each) 5x of Trypsin Inhibitor, Defined (1X) Solution – 100 mL – from Sigma-Aldrich Online Catalogue. Price ($33.70 each) 10 Chicken Legs. Price (~$20) David Tseng