3.2

Sample Transfer

and Chamber

Assembly

After static preculture, transfer the samples to the bioreactor cham-

bers under sterile laminar flow environments. Extreme operational

care should be taken when placing 3D scaffolds to avoid cell

scratching.

1. Remove one side of the acrylic seal plate of the bioreactor

chamber. Separate each column enough to insert the sample.

Mount the flow loop tubing system at input and output valves

(see Note 7).

2. Add 180 mL of DMEM medium. Remove all air bubbles inside

the tubing system (see Note 8).

3. Place the scaffold between the columns with the aid of twee-

zers, hold the scaffold and approach the upper column close

enough to couple it. Do not tighten.

4. Add the seal acrylic plate to the chamber and thread it tightly.

Observe the chamber seal o-ring correct positioning.

5. Vertically place the chamber on its specific holder. Align the

upper column to the bottom one carefully to avoid sample

displacement.

6. Add an 0.22 μM syringe filter to the upper aperture that con-

tacts the remaining air volume in the chamber.

7. Place the assembled chamber into the bioreactor system. The

specific mechanic load module and flow rate must be set up

according to the application of interest.

3.3

Mechanical

Compression Load and

Fluid Flow Parameters

One must have in mind that compression and fluid flow parameters

must comply with the material’s mechanical properties. Thus, cell-

free

previous

tests

are

essential

to

determine

the

assays

specifications.

1. Establish a route of the fluid flow through the bioreactor

chamber. To evaluate the flow directly throughout the scaffold,

the tubing system must be assembled in the upper and lower

columns (see Note 9).

2. Setup the peristaltic pump to a continuous flow rate of

0.4 mL/min (see Note 10).

3. Mount the load cell in the bioreactor according to the applied

force range desired as indicated in the equipment reference

manual.

4. Setup the loading parameters (see Note 11): Force value: 1 N;

Frequency: 0.015 Hz; Duration: 1 h continuous; Maximum

duration: 18 h (see Note 12).

Optimized Dynamics in Bioreactors System

131