This study developed mechanically robust, stimuli-responsive hybrid hydrogels (GelMA/acrylamide/PEGDA) infused with citric-acid-derived carbon quantum dots (CQDs) or cysteine-modified CQDs to enable quantitative mechanofluorescence under low compressive stresses relevant to delicate tissue handling and soft robotic grippers. The authors showed that CQD incorporation increased hydrogel stiffness/strength and tuned swelling and wettability, while photoluminescence (PL) intensity decreased under sub-kPa compression (250–1250 Pa), enabling a stress-dependent optical readout attributed primarily to aggregation-caused quenching from reduced interparticle spacing. Sensitivity depended strongly on CQD type and loading (e.g., higher CQD content produced steeper, more linear PL decreases with pressure), and the cysteine-modified formulation improved fibroblast attachment and proliferation over 7 days, supporting potential use as a biocompatible mechano-optical sensing scaffold for mechanobiology and soft robotics.
CELLSCALE INSTRUMENT USED
UniVert
Uniaxial compressive strength testing of the CQD-loaded hybrid hydrogels was performed using a CellScale UniVert to quantify load-bearing performance and compare how CQD type and concentration altered compressive stress–strain behavior (mechanical integrity under compression).
AUTHORS
Masaeli E., Das P., Srinivasan S., Rajabzadeh A.R..