Soft solutions for complex problems: 3D-printed silicone in healthcare Hanna Ryszczuk, Aiswarya Ganapathisankarakrishnan, Jia-En Chen, Brigita De Vega, Harshavardhan Budharaju, Marie Crouillère, François Ganachaud, Dhakshinamoorthy Sundaramurthi, Deepak M. Kalaskar Biomaterials Advances, 2026 Additive manufacturing of silicone holds great promise in revolutionising the field of medicine and medical science. Due to its inertness and unique properties such as elasticity and durability, silicone is widely used in medical applications such as medical devices and biomedical engineering. Additive manufacturing (AM)/3D Printing could expand the potential of silicone even further and allow for the precise & fast fabrication of complex silicone structures. However, development of additive manufacturing (AM) systems for processing silicone involves substantial challenges, due to its high viscosity, low elastic modulus, and the need for support structures during printing. Nonetheless, recent advancements in additive manufacturing techniques enabled 3D printing of silicone possible, establishing it as a rapidly growing and exciting field in biomedical research. Recent research shows that silicone 3D printing can be successfully utilised for the manufacture of sensors, wearable devices, anatomical models, implants, microfluidic devices, and more. This review provides a thorough analysis of the current state of silicone 3D printing for medical applications, highlighting its limitations as well as the promising opportunities it offers for future advancements.
Advances in 3D Bioprinting of Functional Skeletal Muscle Constructs: Focus on Preclinical Models and Evaluation Strategies Harshavardhan Budharaju, Praveenn Kumar S K, Madhumathi Rajendran, Mahalakshmi Sivasubramanian, Swaminathan Sethuraman, Dhakshinamoorthy Sundaramurthi ACS Biomaterials Science and Engineering, 2026 Skeletal muscle is an important organ system of the human body, which is responsible for maintaining body posture and movement and also plays an essential role in metabolic and endocrine functions. Although skeletal muscle has intrinsic regeneration ability, loss exceeding approximately 20% of the mass or volume of an individual muscle is considered volumetric muscle loss (VML), which requires surgical intervention for repair. Tissue engineered scaffolds prepared using techniques such as electrospinning, hydrogel casting, particulate leaching, freeze-drying, freeze-thawing, and bioprinting are promising for treating VML injuries. In this review, we discuss various extrusion-based bioprinting strategies to fabricate skeletal muscle constructs aimed at treating VML. Further, this review provides a comprehensive overview of various extrusion-based bioprinting techniques to fabricate muscle tissues such as support-based, co-axial, in situ, cryobioprinting, spheroids, and 4D bioprinting. Different bioink systems, their key properties, and similarities with the native extracellular matrix (ECM) are elaborated. In addition, commonly used preclinical models for assessing the efficacy of skeletal muscle constructs, as well as various experimental methods for assessing functional recovery after VML injuries treated with engineered tissue constructs, are discussed. The limitations of current approaches in the successful fabrication of skeletal muscle constructs using bioprinting techniques are highlighted. Finally, the future scope in the development of more efficient experimental tools to assess the in vivo efficacy of bioprinted constructs to treat VML are discussed.
Cell electrowriting: An advanced biofabrication approach for micrometre-scale living tissue fabrication Harshavardhan Budharaju Engineered Regeneration, 2026 • Cell electrowriting (CEW) places living cells with near single-cell precision • Delivers finer detail than melt electrowriting and extrusion bioprinting • Prints aligned, organized cells directly—no post-seeding needed • Unlocks lifelike microvessels and muscle or nerve patterns for function The precise replication of native tissue microarchitecture remains a key challenge in biofabrication. While extrusion-based bioprinting fabricates multicellular constructs for regenerative medicine and drug testing, its typical resolution (∼100 μm) is insufficient to reproduce <50 μm features such as capillaries, aligned myofibres, etc. Electrohydrodynamic (EHD) approaches, such as melt electrowriting (MEW), address this limitation by producing polymer fibres of 1–500 μm in diameter by applying high voltages. Cell electrowriting (CEW) expands this principle to living systems, aiding the direct deposition of cell-laden hydrogel fibres with diameters of 5–40 μm, thereby supporting microscale cell placement and architectures that are unachievable with conventional methods. This review discusses the principles of CEW, strategies for bioink formulation, and assessments of biological performance, with emphasis on recent advances in CEW-based printing approaches. The potential applications, challenges, and outlook of CEW for tissue engineering are also discussed.
Insights on the role of cryoprotectants in enhancing the properties of bioinks required for cryobioprinting of biological constructs Harshavardhan Budharaju, Dhakshinamoorthy Sundaramurthi, Swaminathan Sethuraman Journal of Materials Science Materials in Medicine, 2025 Preservation and long-term storage of readily available cell-laden tissue-engineered products are major challenges in expanding their applications in healthcare. In recent years, there has been increasing interest in the development of off-the-shelf tissue-engineered products using the cryobioprinting approach. Here, bioinks are incorporated with cryoprotective agents (CPAs) to allow the fabrication of cryopreservable tissue constructs. Although this method has shown potential in the fabrication of cryopreservable tissue-engineered products, the impact of the CPAs on the viscoelastic behavior and printability of the bioinks at cryo conditions remains unexplored. In this study, we have evaluated the influence of CPAs such as glycerol and dimethyl sulfoxide (DMSO) on the rheological properties of pre-crosslinked alginate bioinks for cryoprinting applications. DMSO-incorporated bioinks showed a reduction in viscosity and yield stress, while the addition of glycerol improved both the properties due to interactions with the calcium chloride used for pre-crosslinking. Further, tube inversion and printability experiments were performed to identify suitable concentrations and cryobioprinting conditions for bioinks containing CPAs & pre-crosslinked with CaCl2. Finally, based on the printability analysis & cell recovery results, 10% glycerol was used for cryobioprinting and preservation of cell-laden constructs at −80 °C and the viability of cells within the printed structures were evaluated after recovery. Cell viability results indicate that the addition of 10% glycerol to the pre-crosslinked bioink significantly improved cell viability compared to bioinks without CPAs, confirming the suitability of the developed bioink combination to fabricate tissue constructs for on-demand applications.
Bioprinting for drug screening: A path toward reducing animal testing or redefining preclinical research? Harshavardhan Budharaju, Rajendra K. Singh, Hae-Won Kim Bioactive Materials, 2025 Bioprinting is reshaping the field of tissue regeneration and drug screening by creating physiologically accurate and scalable tissue models that reduce the limitations of conventional animal testing. It helps to minimize interspecies variability by developing complex 3D tissue structures that closely mimic the structural and functional characteristics of native tissues, ensuring high reproducibility. Furthermore, it supports more humane and sustainable preclinical testing by aligning with the ethical 3Rs principles (Replacement, Reduction and Refinement). Although bioprinting offers many advantages, its full potential in evaluating drug testing applications has yet to be harnessed. In this review, we discuss the efficacy of key bioprinting techniques in replicating the structural and functional characteristics of engineered tissues, comparing them with their native counterparts. Further, we highlight case studies demonstrating the applications of bioprinted skin, cardiac, hepatic, renal, bone, and cancer models in pharmaceutical research. The commercialization of bioprinted drug testing platforms and their integration into pharmaceutical development are also discussed. Finally, we outline key advantages, current challenges, and future directions needed to establish bioprinting as a transformative tool for preclinical drug testing, aiming to replace traditional animal models.
Biofabrication & cryopreservation of tissue engineered constructs for on-demand applications Harshavardhan Budharaju, Dhakshinamoorthy Sundaramurthi, Swaminathan Sethuraman Biofabrication, 2024 Tissue engineered constructs prepared using conventional scaffold-based approaches have the potential to repair or regenerate damaged tissues and organs. Various scaffold fabrication strategies such as electrospinning, solvent casting, particulate leaching, gas foaming, hydrogels, freeze-drying, and 3D bioprinting have been used to fabricate artificial tissues. In recent times, 3D bioprinting has been predominantly used in various biomedical fields, including healthcare and pharmaceutical applications due to precision in 3D geometry. However, there are no viable strategies to preserve bioprinted constructs for on-demand applications because of the lack of specialized techniques or cryopreservation agents to maintain the cell viability and functionality of the bioprinted tissues. To solve this issue, cryopreservation of bioprinted tissues has emerged in recent years to develop methods to create and cryopreserve bioprinted constructs for on-demand applications. This review discusses various techniques used for producing ready-to-use tissue engineered products such as electrospinning, hydrogels, 3D bioprinting, and other bioprinting approaches. Further, the factors influencing the bioprinted tissues, such as cryoprotectants, polymer types and crosslinker concentrations, crosslinking approaches, viscoelastic properties, storage facilities, etc, were also discussed in detail. The potential of cryopreservable bioprinted tissues in various healthcare applications are elaborated with lucid examples. Finally, the conclusions and possible future directions for the fabrication and cryopreservation of tissue engineered products are highlighted.
Tuning thermoresponsive properties of carboxymethyl cellulose (CMC)–agarose composite bioinks to fabricate complex 3D constructs for regenerative medicine Harshavardhan Budharaju, Harini Chandrababu, Allen Zennifer, Davidraj Chellappan, Swaminathan Sethuraman, Dhakshinamoorthy Sundaramurthi International Journal of Biological Macromolecules, 2024 3D bioprinting has emerged as a viable tool to fabricate 3D tissue constructs with high precision using various bioinks which offer instantaneous gelation, shape fidelity, and cytocompatibility. Among various bioinks, cellulose is the most abundantly available natural polymer & widely used as bioink for 3D bioprinting applications. To mitigate the demanding crosslinking needs of cellulose, it is frequently chemically modified or blended with other polymers to develop stable hydrogels. In this study, we have developed a thermoresponsive, composite bioink using carboxymethyl cellulose (CMC) and agarose in different ratios (9:1, 8:2, 7:3, 6:4, and 5:5). Among the tested combinations, the 5:5 ratio showed better gel formation at 37 °C and were further characterized for physicochemical properties. Cytocompatibility was assessed by in vitro extract cytotoxicity assay (ISO 10993-5) using skin fibroblasts cells. CMC-agarose (5:5) bioink was successfully used to fabricate complex 3D structures through extrusion bioprinting and maintained over 80 % cell viability over seven days. Finally, in vivo studies using rat full-thickness wounds showed the potential of CMC-agarose bulk and bioprinted gels in promoting skin regeneration. These results indicate the cytocompatibility and suitability of CMC-agarose bioinks for tissue engineering and 3D bioprinting applications.
Four-dimension printing in healthcare Muthu Parkkavi Sekar, Harshavardhan Budharaju, Allen Zennifer, Swaminathan Sethuraman, Dhakshinamoorthy Sundaramurthi 3D Printing in Medicine, 2022
Soft solutions for complex problems: 3D-printed silicone in healthcare H Ryszczuk, A Ganapathisankarakrishnan, JE Chen, B De Vega, ... Biomaterials Advances, 214870 , 2026 2026
Advances in 3D bioprinting of functional skeletal muscle constructs: focus on preclinical models and evaluation strategies H Budharaju, PK SK, M Rajendran, M Sivasubramanian, S Sethuraman, ... ACS Biomaterials Science & Engineering 12 (4), 1913-1946 , 2026 2026 Citations: 2
Cell Electrowriting: An Advanced Biofabrication Approach for Micrometre-Scale Living Tissue Fabrication H Budharaju Engineered Regeneration , 2026 2026 Citations: 1
Protein–in–polysaccharide bioink for 3D bioprinting of muscle mimetic tissue constructs to treat volumetric muscle loss H Budharaju, DR Chellappan, D Sundaramurthi, S Sethuraman Carbohydrate Polymers 367, 123993 , 2025 2025 Citations: 7
Bioprinting for drug screening: A path toward reducing animal testing or redefining preclinical research? H Budharaju, RK Singh, HW Kim Bioactive Materials 51, 993-1017 , 2025 2025 Citations: 22
Preparation of thermoresponsive & enzymatically crosslinkable gelatin-gellan gum bioink: a protein-polysaccharide hydrogel for 3D bioprinting of complex soft tissues S Bagewadi, M Rajendran, A Ganapathisankarakrishnan, H Budharaju, ... International Journal of Biological Macromolecules 295, 139563 , 2025 2025 Citations: 11
Insights on the role of cryoprotectants in enhancing the properties of bioinks required for cryobioprinting of biological constructs H Budharaju, D Sundaramurthi, S Sethuraman Journal of Materials Science: Materials in Medicine 36 (1), 8 , 2025 2025 Citations: 10
Biofabrication & cryopreservation of tissue engineered constructs for on-demand applications H Budharaju, D Sundaramurthi, S Sethuraman Biofabrication 16 (4), 042008 , 2024 2024 Citations: 24
Carboxymethyl cellulose-agarose hydrogel in poly (3-hydroxybutyrate-co-3-hydroxyvalerate) nanofibers: A novel tissue engineered skin graft H Budharaju, S Bagewadi, P Devanathan, D Chellappan, ... International Journal of Biological Macromolecules 264, 130565 , 2024 2024 Citations: 20
Tuning thermoresponsive properties of carboxymethyl cellulose (CMC)–agarose composite bioinks to fabricate complex 3D constructs for regenerative medicine H Budharaju, H Chandrababu, A Zennifer, D Chellappan, S Sethuraman, ... International Journal of Biological Macromolecules 260, 129443 , 2024 2024 Citations: 33
Embedded 3D bioprinting–An emerging strategy to fabricate biomimetic & large vascularized tissue constructs H Budharaju, D Sundaramurthi, S Sethuraman Bioactive Materials 32, 356-384 , 2024 2024 Citations: 182
Efficient dual crosslinking of protein–in–polysaccharide bioink for biofabrication of cardiac tissue constructs H Budharaju, D Sundaramurthi, S Sethuraman Biomaterials Advances 152, 213486 , 2023 2023 Citations: 42
Carboxymethyl cellulose-agarose-gelatin: A thermoresponsive triad bioink composition to fabricate volumetric soft tissue constructs MP Sekar, H Budharaju, S Sethuraman, D Sundaramurthi SLAS technology 28 (3), 183-198 , 2023 2023 Citations: 48
Ceramic Materials for 3D Printing of Biomimetic Bone Scaffolds–Current state–of–the–art & Future Perspectives H Budharaju, S Suresh, MP Sekar, B De Vega, S Sethuraman, ... Materials & Design 231 (July 2023), 112064 , 2023 2023 Citations: 180
Four-dimension printing in healthcare MP Sekar, H Budharaju, A Zennifer, S Sethuraman, D Sundaramurthi 3D Printing in Medicine 2, 337-359 , 2023 2023 Citations: 9
Advances in electrospinning and 3D bioprinting strategies to enhance functional regeneration of skeletal muscle tissue M Thangadurai, A Ajith, H Budharaju, S Sethuraman, D Sundaramurthi Biomaterials Advances, 213135 , 2022 2022 Citations: 64
Designer DNA biomolecules as a defined biomaterial for 3D bioprinting applications H Budharaju, A Zennifer, S Sethuraman, A Paul, D Sundaramurthi Materials Horizons 9 (4), 1141-1166 , 2022 2022 Citations: 37
Current standards and ethical landscape of engineered tissues—3D bioprinting perspective MP Sekar, H Budharaju, A Zennifer, S Sethuraman, N Vermeulen, ... Journal of tissue engineering 12, 20417314211027677 , 2021 2021 Citations: 170
Recent advancements in cardiovascular bioprinting and bioprinted cardiac constructs H Budharaju, A Subramanian, S Sethuraman Biomaterials Science 9 (6), 1974-1994 , 2021 2021 Citations: 64
MOST CITED SCHOLAR PUBLICATIONS
Embedded 3D bioprinting–An emerging strategy to fabricate biomimetic & large vascularized tissue constructs H Budharaju, D Sundaramurthi, S Sethuraman Bioactive Materials 32, 356-384 , 2024 2024 Citations: 182
Ceramic Materials for 3D Printing of Biomimetic Bone Scaffolds–Current state–of–the–art & Future Perspectives H Budharaju, S Suresh, MP Sekar, B De Vega, S Sethuraman, ... Materials & Design 231 (July 2023), 112064 , 2023 2023 Citations: 180
Current standards and ethical landscape of engineered tissues—3D bioprinting perspective MP Sekar, H Budharaju, A Zennifer, S Sethuraman, N Vermeulen, ... Journal of tissue engineering 12, 20417314211027677 , 2021 2021 Citations: 170
Advances in electrospinning and 3D bioprinting strategies to enhance functional regeneration of skeletal muscle tissue M Thangadurai, A Ajith, H Budharaju, S Sethuraman, D Sundaramurthi Biomaterials Advances, 213135 , 2022 2022 Citations: 64
Recent advancements in cardiovascular bioprinting and bioprinted cardiac constructs H Budharaju, A Subramanian, S Sethuraman Biomaterials Science 9 (6), 1974-1994 , 2021 2021 Citations: 64
Carboxymethyl cellulose-agarose-gelatin: A thermoresponsive triad bioink composition to fabricate volumetric soft tissue constructs MP Sekar, H Budharaju, S Sethuraman, D Sundaramurthi SLAS technology 28 (3), 183-198 , 2023 2023 Citations: 48
Efficient dual crosslinking of protein–in–polysaccharide bioink for biofabrication of cardiac tissue constructs H Budharaju, D Sundaramurthi, S Sethuraman Biomaterials Advances 152, 213486 , 2023 2023 Citations: 42
Designer DNA biomolecules as a defined biomaterial for 3D bioprinting applications H Budharaju, A Zennifer, S Sethuraman, A Paul, D Sundaramurthi Materials Horizons 9 (4), 1141-1166 , 2022 2022 Citations: 37
Tuning thermoresponsive properties of carboxymethyl cellulose (CMC)–agarose composite bioinks to fabricate complex 3D constructs for regenerative medicine H Budharaju, H Chandrababu, A Zennifer, D Chellappan, S Sethuraman, ... International Journal of Biological Macromolecules 260, 129443 , 2024 2024 Citations: 33
Biofabrication & cryopreservation of tissue engineered constructs for on-demand applications H Budharaju, D Sundaramurthi, S Sethuraman Biofabrication 16 (4), 042008 , 2024 2024 Citations: 24
Bioprinting for drug screening: A path toward reducing animal testing or redefining preclinical research? H Budharaju, RK Singh, HW Kim Bioactive Materials 51, 993-1017 , 2025 2025 Citations: 22
Carboxymethyl cellulose-agarose hydrogel in poly (3-hydroxybutyrate-co-3-hydroxyvalerate) nanofibers: A novel tissue engineered skin graft H Budharaju, S Bagewadi, P Devanathan, D Chellappan, ... International Journal of Biological Macromolecules 264, 130565 , 2024 2024 Citations: 20
Preparation of thermoresponsive & enzymatically crosslinkable gelatin-gellan gum bioink: a protein-polysaccharide hydrogel for 3D bioprinting of complex soft tissues S Bagewadi, M Rajendran, A Ganapathisankarakrishnan, H Budharaju, ... International Journal of Biological Macromolecules 295, 139563 , 2025 2025 Citations: 11
Insights on the role of cryoprotectants in enhancing the properties of bioinks required for cryobioprinting of biological constructs H Budharaju, D Sundaramurthi, S Sethuraman Journal of Materials Science: Materials in Medicine 36 (1), 8 , 2025 2025 Citations: 10
Four-dimension printing in healthcare MP Sekar, H Budharaju, A Zennifer, S Sethuraman, D Sundaramurthi 3D Printing in Medicine 2, 337-359 , 2023 2023 Citations: 9
Protein–in–polysaccharide bioink for 3D bioprinting of muscle mimetic tissue constructs to treat volumetric muscle loss H Budharaju, DR Chellappan, D Sundaramurthi, S Sethuraman Carbohydrate Polymers 367, 123993 , 2025 2025 Citations: 7
Advances in 3D bioprinting of functional skeletal muscle constructs: focus on preclinical models and evaluation strategies H Budharaju, PK SK, M Rajendran, M Sivasubramanian, S Sethuraman, ... ACS Biomaterials Science & Engineering 12 (4), 1913-1946 , 2026 2026 Citations: 2
Cell Electrowriting: An Advanced Biofabrication Approach for Micrometre-Scale Living Tissue Fabrication H Budharaju Engineered Regeneration , 2026 2026 Citations: 1
Soft solutions for complex problems: 3D-printed silicone in healthcare H Ryszczuk, A Ganapathisankarakrishnan, JE Chen, B De Vega, ... Biomaterials Advances, 214870 , 2026 2026
