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International Journal of Bioprinting                                         AI for sustainable bioprinting




            enhanced toughness and recyclability under extreme   bioprinting. 14,72,73  Furthermore, AI optimized printing
            conditions. Ji et al.  introduced a salting-out-based   parameters in real-time, improving construct fidelity,
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            method using poly(N-isopropylacrylamide) hydrogels,   reducing waste, and advancing efficiency. 19,74–76  Lastly,
            enabling reversible solidification and dissolution without   AI-assisted intelligent bioprinting technologies enabled
            chemical crosslinkers or post-processing. Collectively,   powerful  bioprinting  capabilities  with  improved
            these approaches maintain mechanical performance   sustainability. Together, these innovations demonstrate
            while promoting circular material use, offering promising   AI’s pivotal role in driving sustainable bioprinting forward,
            pathways for integrating sustainability into future   aligning with both ecological and functional demands. AI
            bioprinting workflows.                             applications are categorized not only by technical functions
                                                               but also by their potential impact on sustainability.
            3. Artificial intelligence for
            sustainable bioprinting                            3.1. Material discovery and development
                                                               AI  has revolutionized  the incorporation  of  bioactive
            Despite  advances  in  sustainable  hydrogels  for  molecules into hydrogels, significantly enhancing their
            bioprinting, challenges remain in balancing printability,   functionality for bioprinting applications.  Tools like
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            biocompatibility,  biodegradability,  and  mechanical  AlphaFold,  a  deep  learning  model  for  protein  structure
            strength. 18,55,56  Hydrogels must exhibit optimal rheological   prediction, enable precise identification of molecular
            properties for smooth deposition while maintaining   interactions, facilitating the integration of bioactive
            structural integrity.  However, materials often excel in   components such as growth factors, peptides, and
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            one attribute at the expense of another—for example,   enzymes into hydrogel matrices for functionalization.
            natural hydrogels offer high biocompatibility but lack the   AI-driven methods allow the  design of hydrogels with
            mechanical robustness needed for complex structures.   tailored properties.
            Beyond material selection, ensuring efficient, reproducible
            bioprinting  is  equally  complex.  Traditional  trial-and-  One notable example of AI’s potential in modeling
            error methods lead to resource inefficiencies, waste, and   molecular interactions is AlphaFold, which has redefined
            prolonged  development  cycles.  Variability  in  bioink   protein  structure  prediction.  AlphaFold,  developed  in
            properties, processing parameters, and post-printing   three successive versions (AlphaFold 1, 2, and 3), has
            conditions further impacts cell viability, tissue functionality,   revolutionized protein  structure  prediction. AlphaFold
            and print success, undermining sustainability.     1 introduced neural networks to predict inter-residue
                                                               distances, demonstrating significant advancements in
               AI offers a transformative solution by enhancing   protein  modeling  by  leveraging  evolutionary data  and
            material discovery, process optimization, and print   achieving superior accuracy during the Critical Assessment
            quality. Coined by John McCarthy, the term AI refers to   of Structure Prediction 13.  It is used on multiple sequence
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            the intelligence demonstrated by machines.  Early rule-  alignments (MSAs) and gradient descent algorithms to
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            based AI relied on predefined “if-then” rules, facilitating   model  protein  structures,  achieving  notable  success  in
            data analysis and automation. 59,60  Classical AI introduced   free modeling domains, particularly for proteins lacking
            knowledge-based systems that integrated expert reasoning   homologous templates. AlphaFold 2 advanced this by
            for problem-solving. 61,62  The emergence of machine   incorporating Evoformer blocks to integrate spatial and
            learning (ML) revolutionized AI, enabling systems to   evolutionary relationships, enabling atomic-level accuracy
            learn from large datasets, recognize complex patterns, and   in 3D structural predictions, as shown in the Critical
            predict material and print outcomes beyond the limitations   Assessment of Structure Prediction 14.  It achieved near-
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            of predefined rules. 63–66                         experimental accuracy for most targets, effectively modeling
               By combining the structured, efficient automation of   long-range residue interactions and folding pathways, but
            classical AI with the adaptability and predictive capabilities   remained computationally intensive due to its reliance
            of ML, AI is currently transforming sustainable bioprinting   on MSAs. AlphaFold 3 further enhanced capabilities
            across multiple dimensions. 67–71  In hydrogel design,   with a diffusion-based architecture, replacing Evoformer
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            AI accelerated the discovery of materials that balance   with Pairformer  (Figure 3). This eliminates MSA
            functionality, printability, and sustainability by predicting   dependency while enabling accurate modeling of protein
            their behavior under diverse conditions and minimizing   complexes, including protein–ligand and protein–nucleic
            the resource-intensive nature of traditional development.    acid interactions. Its experimental results demonstrated
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            AI-driven  approaches  also  enhanced  material  screening   superior performance in predicting multi-component
            processes, ensuring bioinks meet the specific mechanical,   systems, with applications extending to chemically
            biological,  and  environmental  requirements  for  modified residues and novel biomolecular assemblies.


            Volume 11 Issue 4 (2025)                       137                            doi: 10.36922/IJB025170164
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