Fish scale-derived hydroxyapatite for alveolar ridge preservation.

Alveolar ridge resorption following tooth extraction poses significant challenges for future dental restorations. This study investigated the efficacy of fish scale-derived hydroxyapatite (FSHA) as a socket preservation graft material to maintain alveolar bone volume and architecture. FSHA was extracted from *Labeo rohita* fish scales and characterized using Fourier transform infrared (FTIR) analysis. In vitro, biocompatibility and osteogenic potential were assessed using Saos-2 human osteosarcoma cells. Cell viability, migration, and proliferation were evaluated using MTT and scratch assays. In vivo performance was assessed in a rat model, and FSHA was compared to a commercial xenograft (Osseograft) and ungrafted controls. Histological analysis was performed at 8-week post-implantation to quantify new bone formation. FTIR confirmed the purity and homogeneity of FSHA. In vitro, FSHA enhanced Saos-2 viability, migration, and proliferation compared to controls. In vivo, FSHA demonstrated superior bone regeneration compared to Osseograft and ungrafted sites, with balanced graft resorption and new bone formation. Histological analysis revealed an active incorporation of FSHA into new bone, with minimal gaps and ongoing remodeling. Approximately 50%-60% of FSHA was resorbed by 8 weeks, closely matching the rate of new bone deposition. FSHA stimulated more bone formation in the apical socket region than in coronal areas. In conclusion, FSHA is a promising biomaterial for alveolar ridge preservation, exhibiting excellent biocompatibility, osteogenic potential, and balanced resorption. Its ability to promote robust bone regeneration highlights its potential as an effective alternative to currently used graft materials in socket preservation procedures.

Sprayable hydroxypropyl chitin/collagen extract of Ampelopsis brevipedunculata hydrogel accelerates wound healing.

OBJECTIVE: Keeping a wound moist can allow effective and rapid healing, and it can control the formation of scabs, thereby allowing cell proliferation and epithelial formation. When regularly changing a dressing, thermosensitive hydrogel as a moist dressing does not cause a secondary wound from adhesion. The main aim of this study was to evaluate the effect of a new sprayable thermosensitive hydrogel on wound healing. METHOD: The hydrophobic N-acetyl group of chitin was removed by microwave reaction with lye until the degree of acetylation was 60%, followed by reaction with propylene oxide to obtain hydroxypropyl chitin (HPCH) with a degree of substitution of 40%. After mixing HPCH with fish scale collagen (FSC), a thermosensitive hydrogel with a gel temperature of 26.5°C was obtained. Ampelopsis brevipedunculata extracts (ABE), which have been found to accelerate wound repair and improve healing, were added. HPCH/FSC is not toxic to the mouse L929 cell line and forms a hydrogel at body surface temperature. It can be easily sprayed on a wound. The HPCH/FSC has a three-dimensional network porous structure with a swelling ratio of 10.95:1 and a water vapour transmission rate of 2386.03±228.87g/m2/day; it can facilitate the penetration of water and air, and promote absorption of wound exudate. Wound repair was performed on five Sprague-Dawley rats. Each rat had three wounds, which were treated with medical gauze, HPCH/FSC and HPCH/FSC/ABE, respectively. RESULTS: The wounds in the HPCH/FSC/ABE group recovered the fastest in vivo, the mature wound site was smoother, the re-epithelialisation was even and thicker, and the angiogenesis developed rapidly to the mature stage. CONCLUSION: In this study, HPCH/FSC/ABE thermosensitive hydrogel was shown to effectively accelerate wound healing and was convenient for practical application.

Development of luminescence carbon quantum dots for metal ions detection and photocatalytic degradation of organic dyes from aqueous media.

In the present study, fish scale waste was used for the organic synthesis of luminescence CQDs by the hydrothermal method. The impact of CQDs on improved photocatalytic degradation of organic dyes and metal ions detection is examined in this study. The synthesized CQDs had a variety of characteristics that were detected, such as crystallinity, morphology, functional groups, and binding energies. The luminescence CQDs showed outstanding photocatalytic effectiveness for the destruction of methylene blue (96.5%) and reactive red 120 dye (97.8%), respectively after 120 min exposure to visible light (420 nm). The high electron transport properties of the CQDs edges, which make it possible to efficiently separate electron-hole pairs, are attributed to the enhanced photocatalytic activity of the CQDs. These degradation results prove that the CQDs are the outcome of a synergistic interaction between visible light (adsorption); a potential mechanism is also suggested, and the kinetics is analyzed to use a pseudo-first-order model. Additionally, the metal ions detection of CQDs was studied by various metal ions (Hg2+, Fe2+, Cu2+, Ni2+, and Cd2+) in an aqueous solution and results revealed that the PL intensity of CQDs in presence of cadmium ions decreased. Studies show that the organic fabrication of CQDs are effective photocatalyst and may one day serve as the ideal material to reduce water pollution.

BMSC exosome-enriched acellular fish scale scaffolds promote bone regeneration.

Tissue engineering scaffolds are essential for repairing bone defects. The use of biomimetic scaffolds for bone tissue engineering has been investigated for decades. To date, the trend in this area has been moved toward the construction of biomimetic acellular scaffolds with effective modification to enhance the osteogenic differentiation efficiency of bone marrow mesenchymal stem cells (BMSCs). The exosomes derived from BMSCs have been shown as a potential therapeutic tool for repairing bone defects. In this study, we demonstrated the pro-osteogenic effects of exosomes derived form osteogenic differentiated BMSCs (OBMSC) and presented a novel exosmes-functionalized decellularized fish scale (DE-FS) scaffold for promoting bone regeneration in vivo. The DE-FS scaffolds were obtained through decellularization and decalcification processes, which exhibited high biocompatibility and low immunological rejection. The intrinsic anisotropic structures of DE-FS could enhance the adhesion and proliferation ability of BMSCs in vitro. In addition, we demonstrated that the porous structure of DE-FS endowed them with the capacity to load and release exosomes to BMSCs, resulting in the enhanced osteogenic differentiation of BMSCs. Concerning these pro-osteogenic effects, it was further proved that OBMSC exosome-modified DE-FS scaffolds could effectively promote bone regeneration in the mouse calvarial defect models. In conclusion, our work provided a new insight to design exosome-riched biomimetic scaffolds for bone tissue engineering and clinical applications.

Novel therapy using a fish scale collagen scaffold for rotator cuff healing in rat models.

BACKGROUND: Large and massive rotator cuff tears are challenging for surgeons because of postoperative complications such as repaired site retears. Recently, collagen extracted from fish scales has gained more attention because fish byproducts are considered a safer collagen source than other animal-derived scaffolds. This study aimed to evaluate the biological efficacy of tilapia scale-derived collagen scaffolds for rotator cuff repair in rat models. METHODS: The infraspinatus tendon was resected from the greater tuberosity of Sprague-Dawley rats. In the control group, the tendon edge was sutured directly to the humeral head. In the augmentation group, the repaired site was augmented with a tilapia scale-derived collagen scaffold. Histologic examinations were performed at 2 and 4 weeks postoperatively via safranin O and immunofluorescence staining (isolectin B4 and type II collagen) in the bone-tendon junction. For mechanical analysis, the ultimate failure load of the tendon-humeral head complex was evaluated at 6 weeks postoperatively. RESULTS: During safranin O staining, the repaired enthesis demonstrated greater proteoglycan staining in the augmentation group than in the control group at 4 weeks postoperatively. Compared to controls, the augmentation group had significantly higher vascular staining with isolectin B4 at 2 and 4 weeks postoperatively, type II collagen expression at 4 weeks postoperatively, and ultimate failure load at 6 weeks postoperatively. CONCLUSION: Augmentation therapy using tilapia scale-derived type I collagen scaffolds promoted angiogenesis and fibrocartilage regeneration at the enthesis and provided higher mechanical strength than controls.

Bioinspired design of underwater superoleophobic Poly(N-isopropylacrylamide)/ polyacrylonitrile/TiO2 nanofibrous membranes for highly efficient oil/water separation and photocatalysis.

Inspired by fish scales, this study prepares a thermo-responsive underwater oleophobic PNIPAM/PAN/TiO2 nanofibrous membranes by traditional electrospinning technique using poly-N-isopropylacrylamide (PNIPAM) and polyacrylonitrile (PAN). Thermal properties, mechanical properties, surface chemical composition, wettability, photocatalysis, and oil/water separation of PNIPAM/PAN/TiO2 membrane are explored compared to pure PNIPAM membrane. Result reveals that PAN/TiO2 compounds make PNIPAM membrane with a smaller fiber diameter of 141 nm and high tensile stress of 7.4 MPa, and also decompose 98% of rhodamine B after UV light radiation. This bioinspired design structure endows the membrane with superhydrophilicity with a low water contact angle, and underwater superoleophobicity with a high oil contact angle of 157° (petroleum ether) and 151° (dichloromethane). This membrane can efficiency separate oil/water mixture with a high separation efficiency. Moreover, the resultant PNIPAM/PAN/TiO2 membrane has the bionic fish scale structure, and has wettability respond at lower critical solution temperature making the water flux decreased from 10013 ± 367 L m-2·h-1 to 7713 ± 324 L m-2·h-1, and thus has a potential to be used in purification of reclaimed water and separation of oil from water.

Morphological features of mucous secretory organ and mucous secretion of loach Misgurnus anguillicaudatus skin for friction drag reduction.

We examined the functional morphology of loach Misgurnus anguillicaudatus skin by using synchrotron X-ray micro-computed tomography (SR-µCT) and high-contrast staining using osmium tetroxide or phosphotungstic acid (PTA), which enhances the image contrast of soft tissues. The captured high-spatial resolution images revealed that the surface ornamentations were stuck in the basement membrane of the loach scales. The ornamentations consisting of grooves (radii) and ridges (circuli) that can move freely and bend flexibly. The cross-sectional lateral microstructures of flat, concave and convex loach skins were observed from a live image of loach skin obtained through dark-field optical coherence tomography (OCT) imaging. The thickness of loach skin was changed with varying empty space between the mucous-cell layer and the scales by bending motion of loach. In addition, through direct measurement of drag reduction of loach skin, the mucous layer was found to have a strong influence on the reduction of skin friction. The present results enhance the understanding of the functional morphologies of mucous layer of loach to secrete mucus for skin friction reduction.

Streak formation in flow over biomimetic fish scale arrays.

The surface topology of the scale pattern from the European sea bass (Dicentrarchus labrax) was measured using a digital microscope and geometrically reconstructed using computer assisted design modelling. Numerical flow simulations and experiments with a physical model of the surface pattern in a flow channel mimic the flow over the fish surface with a laminar boundary layer. The scale array produces regular rows of alternating, streamwise low-speed and high-speed streaks inside the boundary layer close to the surface, with maximum velocity difference of approximately 9%. Low velocity streaks are formed in the central region of the scales whereas the high velocity streaks originated in the overlapping region between the scales. Thus, those flow patterns are linked to the arrangement and the size of the overlapping scales within the array. Because of the velocity streaks, total drag reduction is observed when the scale height is small relative to the boundary layer thickness, i.e. less than 10%. Flow simulations were compared with surface oil-flow visualisations on the physical model of the biomimetic surface placed in a flow channel. The results show an excellent agreement in the size and arrangement of the streaky structures. The existence of streaks is also shown on sea bass and common carp (Cyprinus carpio) by surface flow visualisation. From comparisons with recent literature on micro-roughness effects on laminar boundary layer flows, it is hypothesised that the fish scales could delay transition, which would further reduce the drag.

Do Scales of the Cichlid Altolamprologus compressiceps in Lake Tanganyika Function as a Morphological Defense Against Scale-Eating?

Many cichlid species in the shallow-shore of Lake Tanganyika suffer damage from attacks by the scale-eater Perissodus microlepis. Many prey fish engage in warning behaviors to this predator. It has been hypothesized that, if prey fish have difficulty employing such behavioral tactics, morphological defenses against scale-eating, such as hard scales, will evolve. The shrimp-eating cichlids, Altolamprologus compressiceps (Ac) and Neolamprologus fasciatus (Nf), exhibit hunting behaviors in which they remain motionless for up to 10 seconds while aiming at prey, when they are vulnerable to scale-eating predators; thus, these fish have likely evolved morphological defenses against "scale-attacks". We tested this hypothesis in Ac and Nf, as well as three other predatory fish, Lamprologus callipterus, Lepidiolamprologus elongatus and Lep. attenuatus, that are not motionless for such a long time. Under natural conditions, Ac and Nf were rarely attacked, while the other three species were attacked frequently. When freshly killed specimens of these five species were displayed underwater in the presence of P. microlepis, Ac was rarely attacked, while Nf and the three other species were attacked frequently. Among the five fish species, the force required to tear off scales was highest for Ac, and this force was negatively correlated with the frequency of attacks on the displayed fish. These results support the hypothesis that the hard scales of Ac function as an anti-scale-attack measure, although it remains unclear why free-swimming Nf were rarely attacked while aiming at prey, despite the fact that the force required to tear off its scales was not large.

Fish Scale Valorization by Hydrothermal Pretreatment Followed by Enzymatic Hydrolysis for Gelatin Hydrolysate Production.

Protein hydrolysates from fish by-products have good process suitability and bioavailability in the food industry. The objective of this work was to develop a method for protein recovery from fish scales and evaluate the hydrolysis of the scale protein. The effect of the hydrothermal process on protein recovery, degree of hydrolysis (DH) and structural properties of the hydrolysates was investigated. Results showed that hydrothermal treatment could enhance protein recovery of tilapia scales without demineralization and dramatically improve the DH of the hydrolysates. The hydrothermal treated scales showed a better protein recovery (84.81%) and DH (12.88%) and released peptides more efficiently than that of the conventional treated samples. The obtained gelatin hydrolysates mainly distributed in the range of 200-2000 Da with an angiotensin I-converting enzyme (ACE) IC50 value of 0.73 mg/mL. The ACE inhibitory activity of gelatin hydrolysates was stable under high temperature, pH and gastrointestinal proteases. Hydrothermal treatment followed by enzymatic hydrolysis offers a potential solution for preparation of gelatin hydrolysates for food ingredients from fish processing by-products.

Effect of Potassium Sorbate and Ultrasonic Treatment on the Properties of Fish Scale Collagen/Polyvinyl Alcohol Composite Film.

Composite films containing different amounts of potassium sorbate (KS) were prepared by using fish scale collagen (Col) and polyvinyl alcohol (PVA). Fourier transform infrared spectroscopy (FTIR), light transmittance, mechanical, water vapor transmission rate (WVTR), and the antibacterial properties of the composite films were analyzed. The results showed that the addition of Col significantly reduced the light transmittance of the composite film, but KS had no significant effect on the light transmission. The tensile strength decreased first and then increased with the addition of KS, while the WVTR increased first and then decreased. The composite film exhibited a certain degree of antibacterial properties against E. coli and S. aureus. In addition, we found that ultrasonic treatment reduced the WVTR, and also improved tensile strength and elongation at break of the composite films, but had no significant effect on other properties. The KS/Col/PVA films have the potential to be used as antimicrobial food packaging.

Antioxidant and anti-inflammatory capacities of collagen peptides from milkfish (Chanos chanos) scales.

Milkfish (Chanos chanos), which is resistant to water quality changes is the fourth largest aquaculture commodity. Abandoned wastes of fish scale and bones aggravate environmental pollution. In this study, the effect of collagen peptides isolated from milkfish scales (MSCP) by pepsin-soluble collagen method on cell viability was investigated. The antioxidant, anti-inflammatory, and DNA-protective activities of MSCP were also evaluated. Results revealed that more than 95% of viable cells were retained in human keratinocytes after addition of 100 mg/mL MSCP. Measurement of DPPH· and ABTS· + radical scavenging activities and cellular reactive oxygen species revealed the high antioxidant activities of MSCP. MSCP demonstrated anti-inflammatory activities by reducing lipoxygenase activity and nitric oxide (NO·) radicals. Moreover, DNA electrophoresis assay indicated that MSCP treatment can directly protect against cyclobutane di-pyrimidine production and DNA single-strand breaks, which are harmful effects of UV radiation and H2O2. Given its antioxidant, anti-inflammatory, and DNA-protective activities, MSCP has potential applications in cosmeceuticals and supplementary health food.

Lidocaine-loaded fish scale-nanocellulose biopolymer composite microneedles.

Microneedle (MN) technology has emerged as an effective drug delivery system, and it has tremendous potential as a patient friendly substitute for conventional methods for transdermal drug delivery (TDD). In this paper, we report on the preparation of lidocaine-loaded biodegradable microneedles, which are manufactured from fish scale-derived collagen. Lidocaine, a common tissue numbing anaesthetic, is loaded in these microneedles with an aim of delivering the drug with controlled skin permeation. Evaluation of lidocaine permeation in porcine skin has been successfully performed using Franz diffusion cell (FDC) which has shown that the drug permeation rate increases from 2.5 to 7.5% w/w after 36 h and pseudo steady state profile is observed from 5.0 to 10.0% w/w lidocaine-loaded microneedle. Swelling experiments have suggested that the microneedles have negligible swellability which implies that the patch would stick to the tissue when inserted. The experiments on MN dissolution have depicted that the lidocaine loaded in the patch is lower than the theoretical loading, which is expected as there can be losses of the drug during initial process manufacture.

Mechanical, optical, chemical, and biological evaluations of fish scale-derived scaffold for corneal replacements: A systematic review.

Corneal blindness is commonly treated through corneal replacement with allogeneic corneal donors, which may face shortage. Regarding this issue, xenogeneic alternatives are explored. Fish scale-derived scaffolds (FSSs) are among the alternatives due to the lower risk of infection and abundant sources of raw materials. Unfortunately, the information about mechanical, optical, chemical, and biological performances of FSSs for corneal replacements is still scattered, as well as about the fabrication techniques. This study aims to gather scattered pieces of information about the mentioned performances and fabrication techniques of FSSs for corneal replacements. Sorted from four scientific databases and using the PRISMA checklist, eleven relevant articles are collected. FSSs are commonly fabricated using decellularization and decalcification processes, generating FSSs with parallel multilayers or crossed fibers with topographic microchannels. In the collected studies, similar mechanical properties of FSSs to native tissues are discovered, as well as good transparency, light remittance, but poorer refractive indexes than native tissues. Biological evaluations mostly discuss histology, cell proliferations, and immune responses on FSSs, while only a few studies examine the vascularization. No studies completed comprehensive evaluations on the four properties. The current progress of FSS developments demonstrates the potential of FSS use for corneal replacements.

Laser Ablating Biomimetic Periodic Array Fish Scale Surface for Drag Reduction.

Reducing resistance to surface friction is challenging in the field of engineering. Natural biological systems have evolved unique functional surfaces or special physiological functions to adapt to their complex environments over centuries. Among these biological wonders, fish, one of the oldest in the vertebrate group, have garnered attention due to their exceptional fluid dynamics capabilities. Fish skin has inspired innovation in reducing surface friction due to its unique structures and material properties. Herein, drawing inspiration from the unique properties of fish scales, a periodic array of fish scales was fabricated by laser ablation on a polished aluminum template. The morphology of the biomimetic fish scale surface was characterized using scanning electron microscopy and a white-light interfering profilometer. Drag reduction performance was measured in a closed circulating water tunnel. The maximum drag reduction was 10.26% at a Reynolds number of 39,532, and the drag reduction performance gradually decreased with an increase in the distance between fish scales. The mechanism of the biomimetic drag reduction surface was analyzed using computational fluid dynamics. Streamwise vortices were generated at the valley of the biomimetic fish scale, replacing sliding friction with rolling friction. These results are expected to provide a foundation for in-depth analysis of the hydrodynamic performance of fish and serve as new inspiration for drag reduction and antifouling.

Fish Scale for Wearable, Self-Powered TENG.

Flexible and wearable devices are attracting more and more attention. Herein, we propose a self-powered triboelectric nanogenerator based on the triboelectric effect of fish scales. As the pressure on the nanogenerator increases, the output voltage of the triboelectric nanogenerator increases. The nanogenerator can output a voltage of 7.4 V and a short-circuit current of 0.18 µA under a pressure of 50 N. The triboelectric effect of fish scales was argued to be related to the lamellar structure composed of collagen fiber bundles. The nanogenerator prepared by fish scales can sensitively perceive human activities such as walking, finger tapping, and elbow bending. Moreover, fish scales are a biomass material with good biocompatibility with the body. The fish-scale nanogenerator is a kind of flexible, wearable, and self-powered triboelectric nanogenerator showing great prospects in healthcare and body information monitoring.

Self-assembled nanoparticles of acid-induced fish (Cyprinus carpio L.) scale gelatin: Structure, physicochemical properties, and application for loading curcumin.

This work expands the functionality of fish scale gelatin (FSG) as a carrier of hydrophobic bioactive substances. The hydrophobicity of FSG was enhanced to promote its interaction with hydrophobic curcumin and to increase its bioavailability. This results in a remarkable increase in the curcumin loading capacity of acid-hydrolyzed FSG (HFSG) from 1.08 ± 0.08 µg/mg (0 h) to 9.15 ± 0.21 µg/mg (3 h). The amino acid composition indicated that acid hydrolysis effectively increased the ratio of hydrophobic amino acids of FSG. Acid hydrolysis facilitated the transformation of the α-helical conformation into a ß-sheet structure. Hydrophobic interactions between HFSG and curcumin were strengthened by moderate acid hydrolysis. A sustained-release profile emerged for the curcumin-loaded HFSG during simulated gastrointestinal digestion, thereby improving the bioaccessibility and bioavailability of curcumin. These findings contribute to the application of acid hydrolysis in modifying FSG for enhanced hydrophobicity and curcumin loading capacity in the food industry.

Fabrication of Fish Scale-Based Gelatin Methacryloyl for 3D Bioprinting Application.

Gelatin methacryloyl (GelMA) is an ideal bioink that is commonly used in bioprinting. GelMA is primarily acquired from mammalian sources; however, the required amount makes the market price extremely high. Since garbage overflow is currently a global issue, we hypothesized that fish scales left over from the seafood industry could be used to synthesize GelMA. Clinically, the utilization of fish products is more advantageous than those derived from mammals as they lower the possibility of disease transmission from mammals to humans and are permissible for practitioners of all major religions. In this study, we used gelatin extracted from fish scales and conventional GelMA synthesis methods to synthesize GelMA, then tested it at different concentrations in order to evaluated and compared the mechanical properties and cell responses. The fish scale GelMA had a printing accuracy of 97%, a swelling ratio of 482%, and a compressive strength of about 85 kPa at a 10% w/v GelMA concentration. Keratinocyte cells (HaCaT cells) were bioprinted with the GelMA bioink to assess cell viability and proliferation. After 72 h of culture, the number of cells increased by almost three-fold compared to 24 h, as indicated by many fluorescent cell nuclei. Based on this finding, it is possible to use fish scale GelMA bioink as a scaffold to support and enhance cell viability and proliferation. Therefore, we conclude that fish scale-based GelMA has the potential to be used as an alternative biomaterial for a wide range of biomedical applications.

Uncertainty analysis of Altantic salmon fish scale's acoustic impedance using 30 MHz C-Scan measurements.

Understanding the biomechanics of fish scales is crucial for their survival and adaptation. Ultrasonic C-scan measurements offer a promising tool for non-invasive characterization, however, existing literature lacks uncertainty analysis while evaluating acoustic impedance. This article presents an innovative integration of uncertainty into the analytical framework for estimating stochastic specific acoustic impedance of salmon fish scale through ultrasonic C-scans. In this study, the various types of uncertainties arising due to variation in biological structures and aging, measurement errors, and analytical noises are combined together in the form of uncertain reflectance. This uncertain reflectance possesses a distribution which is derived using a theory of waves by assuming suitable stochasticity in wavenumber. This distribution helps in development of a stochastic-specific acoustic impedance map of the scales which demonstrates the possible deviations of impedance from mean value depending on uncertainties. Furthermore, maximal overlap discrete wavelet transform is employed for efficient time-frequency deconvolution and Kriging for spatial data interpolation to enhance the robustness of the impedance map, especially in scenarios with limited data. The framework is validated by accurately estimating the specific acoustic impedance of well-known materials like a pair of target medium (polyvinylidene fluoride) and reference medium (polyimide), achieving over 90% accuracy. Moreover, the accuracy of the framework is found superior when compared with an established approach in the literature. Applying the framework to salmon fish scales, we obtain an average specific acoustic impedance of 3.1 MRayl along with a stochastic map visualizing the potential variations arising from uncertainties. Overall, this work paves the way for more accurate and robust studies in fish scale biomechanics by incorporating a comprehensive uncertainty analysis framework.

Fish scale containing alginate dialdehyde-gelatin bioink for bone tissue engineering.

The development of biomaterial inks suitable for biofabrication and mimicking the physicochemical properties of the extracellular matrix is essential for the application of bioprinting technology in tissue engineering (TE). The use of animal-derived proteinous materials, such as jellyfish collagen, or fish scale (FS) gelatin (GEL), has become an important pillar in biomaterial ink design to increase the bioactivity of hydrogels. However, besides the extraction of proteinous structures, the use of structurally intact FS as an additive could increase biocompatibility and bioactivity of hydrogels due to its organic (collagen) and inorganic (hydroxyapatite) contents, while simultaneously enhancing mechanical strength in three-dimensional (3D) printing applications. To test this hypothesis, we present here a composite biomaterial ink composed of FS and alginate dialdehyde (ADA)-GEL for 3D bioprinting applications. We fabricate 3D cell-laden hydrogels using mouse pre-osteoblast MC3T3-E1 cells. We evaluate the physicochemical and mechanical properties of FS incorporated ADA-GEL biomaterial inks as well as the bioactivity and cytocompatibility of cell-laden hydrogels. Due to the distinctive collagen orientation of the FS, the compressive strength of the hydrogels significantly increased with increasing FS particle content. Addition of FS also provided a tool to tune hydrogel stiffness. FS particles were homogeneously incorporated into the hydrogels. Particle-matrix integration was confirmed via scanning electron microscopy. FS incorporation in the ADA-GEL matrix increased the osteogenic differentiation of MC3T3-E1 cells in comparison to pristine ADA-GEL, as FS incorporation led to increased ALP activity and osteocalcin secretion of MC3T3-E1 cells. Due to the significantly increased stiffness and supported osteoinductivity of the hydrogels, FS structure as a natural collagen and hydroxyapatite source contributed to the biomaterial ink properties for bone engineering applications. Our findings indicate that ADA-GEL/FS represents a new biomaterial ink formulation with great potential for 3D bioprinting, and FS is confirmed as a promising additive for bone TE applications.