The optimized protocol was then tested on round pillars of identical dimensions but 3D printed with the rest of the developed inks (inks 1-4, Figure , Table ). For comparison, the same structures were tested using the 'standard' nanoindentation protocol (Figure ). For the inks prepared using DEABP as photoinitiator (inks 1-2) the reduced moduli determined using the optimized protocol were 2.07 ± 0.05 MPa, 2.80 ± 0.14 MPa and 2.20 ± 0.01 MPa, respectively. In contrast, the values obtained using the 'standard' protocol were significantly higher: