Page 149 - v11i4
P. 149

International Journal of Bioprinting                                         AI for sustainable bioprinting




            3.3. Processing parameters optimization            and enhanced porosity, factors critical for promoting
            Besides  optimizing bioink  formulations, achieving   cell proliferation and tissue regeneration. In vivo diabetic
            consistent and high-fidelity bioprinted constructs also   wound healing models showed that AI-optimized scaffolds
            depends on precise control of printing parameters   accelerated  re-epithelialization,  improved  collagen
            such  as  extrusion  speed,  nozzle  pressure,  and  layer   deposition, and enhanced vascularization, demonstrating
            stacking accuracy. Variations in processing conditions   superior therapeutic potential over conventionally printed
            can significantly impact construct stability, resolution,   scaffolds. This AI-assisted workflow minimizes resource
            and cellular viability. 67,82,83  Traditional approaches to   consumption, ensures reproducibility, and enhances the
            address these challenges involve extensive trial-and-  scalability of bioprinting.
            error experiments to fine-tune such parameters and can        87
            be time- and resource-consuming. Addressing these     Fu et al.  investigated the effects of printing
            complexities through AI-driven optimization offers   parameters on the printability of Pluronic F127 hydrogels
            a transformative approach to enhancing bioprinting   in extrusion-based 3D bioprinting and introduced an
            efficiency and accuracy. 71,84                     ML-guided optimization framework (Figure 5C). The
                                                               researchers examined the influence of nozzle temperature,
               Bone et al.  introduced a hierarchical ML (HML)   nozzle gauge, path height, and material composition on
                        85
            framework for optimizing 3D bioprinting alginate   printability, using the width index as the primary output
            biopolymer (Figure 5A). The dataset included 48 alginate   metric. They trained a support vector machine model on
            hydrogel prints, with input parameters of ink concentration,   12 data points selected via uniform design across three key
            flow rate, nozzle speed, and nozzle diameter, and output   parameters—concentration, nozzle temperature, and path
            targets defined as print fidelity metrics (line width and   height—and  generated  a  3D  process  map  that  predicted
            corner radius errors). The HML approach leverages domain   optimal printing regions with over 75% probability of high-
            knowledge, incorporating integrated system variables (e.g.,   fidelity output. While the study demonstrates the potential
            nozzle speed, flow rate, ink concentration) with middle-  of ML to reduce trial-and-error and improve parameter
            layer physical relationships (e.g., effective shear rate,   selection, the small dataset limits generalizability. Future
            viscosity, proportionality laws) to predict and optimize   work should focus on expanding the parameter space and
            print fidelity. Experimental validation demonstrated   dataset size, incorporating additional variables such as
            that the HML framework accurately predicts optimal   crosslinking conditions and cell viability, and establishing
            printing parameters, achieving high-fidelity prints with   standardized  printability  metrics  to  enable  broader
            less than 10% dimensional error. The study also highlights   applicability and model reproducibility across materials
            the trade-offs in optimizing specific features, such as   and platforms.
            linewidths and corner radii, emphasizing the need for
                                                                          88
            multi-objective optimization.                         Xu et al.  developed a predictive framework for
                                                               assessing cell viability in stereolithography-based
               Chen et al.   demonstrated an AI-driven approach   3D-bioprinted  gelatin  structures,  addressing  the
                        86
            to optimizing 3D bioprinting parameters, enhancing   limitations of physics-based models through an ensemble
            both efficiency and sustainability (Figure 5B). The AI-  ML  approach  combining  ridge  regression,  k-nearest
            assisted high-throughput printing–condition–screening   neighbors, random forest, and neural networks. The model
            system integrates a programmable pneumatic extrusion   was trained and validated on 405 cell viability data points
            bioprinter with an AI-powered image-analysis algorithm,   collected from 81 bioprinting conditions, using gelatin
            systematically optimizing key parameters such as printing   methacrylate concentration, UV intensity, UV exposure
            pressure, nozzle speed, and printing distance. The model   time, and layer thickness as input features. Results showed
            was trained on 280 labeled images of alginate–gelatin   that UV exposure time had the greatest impact on cell
            hydrogel prints, using deep learning to classify extrusion   viability, followed by layer thickness, gelatin methacrylate
            states and predict optimal print conditions. By automating   concentration, and UV intensity.
            the screening process, the AI-assisted high-throughput
            printing–condition–screening system eliminates reliance   Zhang et al.  developed an integrated framework
                                                                            89
            on extensive trial-and-error experimentation, reducing   combining advanced rheological modeling, computational
            material waste while ensuring high-quality scaffold   fluid dynamics simulations, and ML to predict as-extruded
            fabrication. Experimental results demonstrated that the AI-  cell viability in extrusion-based 3D bioprinting. The study
            assisted approach led to a 45% reduction in optimization   used support vector regression to predict Cross power
            time, significantly lowering  the consumption of  bioinks   law parameters for alginate inks based on 76 rheological
            and resources. The optimized hydrogel scaffolds exhibited   measurements across different concentrations  and
            improved mechanical stability, uniform fiber alignment,   temperatures, and trained multilayer perceptron regressors

            Volume 11 Issue 4 (2025)                       141                            doi: 10.36922/IJB025170164
   144   145   146   147   148   149   150   151   152   153   154