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The synthesis of ideal bioceramics to guide the fate of cells and subsequent bone regeneration within the chemical, biological, and physical microenvironment is a challenging long-term task. This study developed amorphous calcium magnesium phosphate (ACMP) bioceramics via a simple co-precipitation method. The role of Mg2+ in the formation of ACMP is investigated using physicochemical and biological characterization at different Ca/Mg molar ratio of the initial reaction solution. Additionally, ACMP bioceramics show superior cytocompatibility and improved osteogenic differentiation of co-cultured MC3T3-E1 cells. Regulation of the microenvironment with Mg2+ can promote early-stage bone regeneration. For this, bioprinting technology is employed to prepare ACMP-modified 3D porous structures. Our hypothesis is that the incorporation of ACMP into methacrylated gelatin (GelMA) bioink can trigger the osteogenic differentiation of encapsulated preosteoblast and stimulate bone regeneration. The cell-laden ACMP composite structures display stable printability and superior cell viability and cell proliferation. Also, constructs loading the appropriate amount of ACMP bioceramic showed significant osteogenic differentiation activity compared to the pure GelMA. We demonstrate that the dissolved Mg2+ cation microenvironment in ACMP-modified composite constructs plays an effective biochemical role, and can regulate cell fate. Our results predict that GelMA/ACMP bioink has significant potential in patient-specific bone tissue regeneration. [Display omitted] [ABSTRACT FROM AUTHOR]

Bone defects pose significant challenges in orthopedic surgery, often leading to suboptimal outcomes and complications. Addressing these challenges, we employed a three-electrode electrochemical system to fabricate surface-controlled polyaniline nano-tulips (PANINTs) decorated polycaprolactone (PCL) reinforced chitosan functionalized iron oxide nanoparticles (CS- f -Fe 2 O 3) scaffolds. These structures were designed to emulate the natural extracellular matrix (ECM) and promote enhanced osseointegration by establishing a continuous interface between host bone and graft, thereby improving both biological processes and mechanical stability. In vitro experiments demonstrated that PANINTs-PCL/CS- f -Fe 2 O 3 substrates significantly promoted the proliferation, differentiation, and spontaneous outgrowth and extension of MC3T3-E1 cell activity. The nanomaterials exhibited increased cell viability and osteogenic differentiation, as evidenced by elevated expression of bone-related markers such as ALP, ARS, COL-I, RUNX2, and SPP-I, as determined by qRT-PCR. Our findings underscore the regenerative potential of in situ cell culture systems for bone defects, emphasizing the targeted stimulation of essential cell subpopulations to facilitate rapid bone tissue regeneration. [ABSTRACT FROM AUTHOR]

In pursuit of enhancing bone cell proliferation, this study delves into the fabrication of porous scaffolds through the integration of nanomaterials. Specifically, we present the development of highly conductive chitosan (CS) nanonets on fibro-porous polyurethane (PU) bio-membranes. These nanofibers comprise functionalized multiwall carbon nanotubes (f MWCNTs), well-dispersed superparamagnetic iron oxide (SPIONs), and strontium oxide (SrO 2) nanoparticles. The resulting porous scaffold exhibits remarkable interfacial biocompatibility, antibacterial properties, and load-bearing capability. Through meticulous in vitro investigations, the CS-PU/SPIONs/SrO 2 - f MWCNTs nanofibrous scaffolds have demonstrated a propensity to promote bone cell regeneration. Notably, the integration of these nanomaterials has been found to upregulate crucial bone-related markers, including ALP, ARS, COL-I, RUNX2, and SPP–I. The evaluation of these markers, conducted through quantitative real-time polymerase chain reaction (qRT-PCR) and immunocytochemistry, substantiates the improved cell survival and enhanced osteogenic differentiation facilitated by the integrated nanomaterials. This comprehensive analysis underscores the efficacy of CS-PU/SPIONs/SrO 2 - f MWCNTs bioscaffolds in promoting MC3T3-E1 cell regeneration within, thereby holding promise for advancements in bone tissue engineering and regenerative medicine. [ABSTRACT FROM AUTHOR]

A wound dressing material should inhibit infections that may occur at the wound site, and at the same time, it should enhance the healing process. In this study, we developed an amikacin sulphate (AK) incorporated chitosan (Ch) and Diopside nanoparticles composite dressing (Ch-nDE-AK) for controlling wound infection and healing. The diopside nanoparticles (nDE) were prepared using sol-gel synthesis and characterized using XRD, FT-IR, and FESEM. nDE shows a size range of 142 ± 31 nm through FESEM analysis. Later, the developed composite dressing was characterized using SEM, EDS, and FT-IR analysis. Ch-nDE-AK dressing possesses a porous nature that will aid in easy cell infiltration and proliferation. The swelling studies indicated the expansion capability of the scaffold when applied to the injured site. Ch-nDE-AK scaffold showed a 69.6 ± 8.2 % amikacin sulphate release up to 7 days, which indicates the sustained release of the drug from Ch-nDE-AK scaffold. The drug release data was subjected to various kinetics models and was observed to follow the Higuchi model. The scaffold showed antibacterial activity against ATCC strains of S. aureus and E. coli for 7 days by in vitro. Ch-nDE-AK scaffold also showed antibacterial activity against S. aureus and E. coli clinical strains in vitro. The ex vivo antibacterial study confirmed the antibacterial ability of Ch-nDE-AK scaffold against S. aureus and E. coli. Ch-nDE-AK scaffold also exhibits anti-biofilm activity against S. aureus and E. coli. The Ch-nDE-AK scaffold showed cytocompatibility and cell attachment to fibroblast cells. Additionally, the scratch assay using fibroblast cells confirmed the role of the nDE in the scaffold, helping in cell migration. Thus, the developed Ch-nDE-AK dressing can potentially be used to treat infectious wound healing. [ABSTRACT FROM AUTHOR]

Hydrogels, integrating diverse biocompatible materials, have emerged as promising candidates for bone repair applications. This study presents a double network hydrogel designed for bone tissue engineering, combining poly(ethylene glycol) diacrylate (PEGDA) and chitosan (CS) crosslinked through UV polymerization and ionic crosslinking. Concurrently, copper-doped mesoporous silica nanospheres (Cu-MSNs) were synthesized using a one-pot method. Cu-MSNs underwent additional modification through in-situ biomineralization, resulting in the formation of an apatite layer. Polydopamine was employed to facilitate the deposition of Calcium (Ca) and Phosphate (P) ions on the surface of Cu-MSNs (Cu-MSNs/PDA@CaP). Composite hydrogels were created by integrating varied concentrations of Cu-MSNs/PDA@CaP (25, 50, 100, 150, 200 μg/mL). Characterization unveiled distinctive interconnected porous structures within the composite hydrogel, showcasing a notable 169.6 % enhancement in compressive stress (elevating from 89.01 to 240.19 kPa) compared to pure PEGDA. In vitro biocompatibility experiments illustrated that the composite hydrogel maintained elevated cell viability (up to 106.6 %) and facilitated rapid cell proliferation over 7 days. The hydrogel demonstrated a substantial 57.58 % rise in ALP expression and a surprising 235.27 % increase in ARS staining. Moreover, it significantly enhanced the expression of crucial osteogenic genes, such as run-related transcription factors 2 (RUNX2), collagen 1a1 (Col1a1), and secreted phosphoprotein 1 (Spp1), establishing it as a promising scaffold for bone regeneration. This study shows how Cu-MSNs/PDA@CaP were successfully integrated into a double network hydrogel, resulting in a composite material with good biological responses. Due to its improved characteristics, this composite hydrogel holds the potential for advancing bone regeneration procedures. [ABSTRACT FROM AUTHOR]

We present an integrated design and fabrication strategy for the development of hierarchically structured biomechanically and biologically functional tissue scaffold. An integration of β-TCP incorporated fluffy type nanofibers and biodegradable interpenetrating gelatin-hydrogel networks (IGN) result in biomimetic tissue engineered constructs with fully tunable properties that can match specific tissue requirements. FESEM images showed that nanofibers were efficiently assembled into an orientation of IGN without disturbing its pore architecture. The pore architecture, compressive stiffness and modulus, swelling, and the biological properties of the composite constructs can be tailored by adjusting the composition of nanofiber content with respect to IGN. Experimental results of cell proliferation assay and confocal microscopy imaging showed that the as-fabricated composite constructs exhibit excellent ability for MC3T3-E1 cell proliferation, infiltration and growth. Furthermore, β-TCP incorporated functionalized nanofiber enhanced the biomimetic mineralization, cell infiltration and cell proliferation. Within two weeks of cell-seeding, the composite construct exhibited enhanced osteogenic performance (Runx2, osterix and ALP gene expression) compared to pristine IGN hydrogel scaffold. Our integrated design and fabrication approach enables the assembly of nanofiber within IGN architecture, laying the foundation for biomimetic scaffold. • Biomimetic scaffold with channel-like macroporous architecture is developed. • First time bioactive fluffy type nanofibous mesh is integrated with GelMA hydrogel. • Nanofibers were efficiently assembled an orientation of hydrogel network. • Fibers do not interrupt the macroporous architecture of GelMA. • The pore architecture, stiffness, modulus, and the bioactivity can tailored. [ABSTRACT FROM AUTHOR]

A pH-sensitive polymeric carrier was developed in this study for local delivery of anticancer drug bortezomib (BTZ) to cancer cells. Our strategy is based on the conjugation of BTZ to polymeric carriers containing catechol groups, which are considered to release BTZ selectively in cancer cells. In this study we used alginate-conjugated polydopamine as a building block polymer. The catechol moiety of polydopamine binds to the boronic acid group of BTZ drug and release the drug molecules in a pH-dependent method. Cancer tissue has acidic environment where BTZ dissociate from the catechol group of polydopamine to control the release of the free drug. Mathematical equation models were used to clarify the mechanism of drug release. The release profile fitted first order with correlation coefficient (R2 = 0.98), the release mechanism was studied using Korsmeyer–Peppas, Higuchi, Hixson-Crowell, and Kopcha models. We revealed the release mechanism follows non-fickian and diffusion was the dominant mechanism while small portion contributed to erosion. The pH-sensitive mechanism controls the release of BTZ in targeted cancer cells, hence developing a novel idea that is applicable in future towards other boronic acid-containing drugs to treat various kinds of health challenges. • The AlgPD-BTZ hydrogel presented a chemo selective approach for cancer chemotherapy. • Sustained release profile of BTZ in pH dependent manner • In-depth study of kinetics and mechanism of drug release • The AlgPD-BTZ hydrogel shows remarkable cytotoxicity to cancer cells. [ABSTRACT FROM AUTHOR]

Cellulose I and II polymorphs were isolated from Capsosiphon fulvescens (CF) using the conventional method of extraction and direct mercerization of raw sample, respectively. The morphological and structural differences between the isolated polymorphs were studied by FTIR, FESEM and XRD. Direct mercerization of raw CF yielded the transformation of highly crystalline cellulose I (81.3%) to II (63.7%) as observed in the shifting of XRD patterns. The derived cellulose I and II were hydrolyzed (60% w/w H 2 SO 4 , 55 °C, 1 h, 10 mL/g) to obtain the spindle-shaped cellulose nanocrystals. Cellulose nanocrystal I was observed to have a mean thickness and length of 12.67 ± 2.69 and 92.31 ± 21.31 nm, respectively; while cellulose nanocrystal II has a mean thickness and length of 15.58 ± 2.85 and 78.09 ± 18.22 nm, respectively. Furthermore, a fiber-like mat assembly, which could be used as supplement support structure for tissue engineering, was obtained after subjecting the aqueous cellulose nanocrystal suspensions to freeze-drying. A possible application of this material can be as a biocompatible and biodegradable composite for tissue engineering and other biomedical applications. [ABSTRACT FROM AUTHOR]

We prepared Janus microspheres based on sodium alginate for the encapsulation of mesenchymal stem cells (MSC) in one compartment and iron oxide nanoparticles (IONP) or a drug in the second compartment. 4% percent sodium alginate solution was allowed to pass through a septum-theta capillary device and react with 2.5% calcium chloride to allow crosslinking to occur in the solution, forming calcium alginate Janus microspheres. Physico-chemical characterization of microspheres was done by FTIR, TGA, and XRD after loading of stem cells and IONP/drug. The mechanical integrity of microspheres was tested at different time points, which showed that 4% alginate microspheres were mechanically stable for a long period of time. Live/dead staining of MSCs alone and the MTS assay of MSCs and DMSO co-loaded were performed, which showed less toxicity to MSC in the Janus configuration. IONP/MSC-loaded Janus microspheres were tested by magnetic manipulation for targeted MSC delivery for cartilage repair using an electromagnetic manipulation (EMM) device. Janus microspheres can be used for targeted stem cell/drug delivery using EMM for cartilage repair in the near future. [ABSTRACT FROM AUTHOR]

Through exhaustive extraction via successive alkali and bleaching treatments cellulose was isolated from lettuce. The isolated cellulose was hydrolyzed using 64 wt% H 2 SO 4 at 55 °C under constant stirring for 1 h to obtain cellulose nanocrystals (CNCs). Characterizations such as SEM, TEM, FTIR, TGA and XRD were done in order to determine differences in the physico-chemical characteristics of cellulose after each treatment step. The isolated CNCs have mean dimensions of 237 ± 26, 33 ± 12 and 32 ± 7 nm in length, thickness and height, respectively. These nanocrystals were incorporated to the formulations that were used to fabricate different chitosan-g- d , l -lactic acid (CgLA) scaffolds. Amide linkage formation between chitosan and lactic acid and further removal of water was facilitated by oven-drying under vacuum at 80 °C. Results show that an increase in the concentration of CNCs added, increase in porosity, degradability, drug release property and cell viability were observed from the fabricated composite scaffolds. These results can provide information on how nanofillers such as CNCs can alter the properties of tissue scaffolds through the chemical properties and interactions they provide. Moreover, these characteristics can give new properties that are necessary for certain tissue engineering applications. [ABSTRACT FROM AUTHOR]

Wound dressing is a very important factor in the process of wound healing as proper wound care can accelerate the recovery of the wound. In this study, zein nanofibrous mats with fiber diameters around 350–500 nm were prepared by electrospinning and silver (Ag) nanoparticles around 20 nm were concurrently synthesized in situ into the mats. The electrospun nanofibers were characterized by Field Emission-Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis. Cell viability and activity of fibroblasts cells in zein/Ag mats were also evaluated and results demonstrated good cytocompatibility and attachment of cells on the composite nanofibers. Also, the bactericidal activity of the fabricated mats against gram-positive Staphylococcus aureus ( S. aureus ) and gram-negative Escherichia coli ( E. coli ) was investigated via zone of inhibition test and results showed high anti-bacterial performance. [ABSTRACT FROM AUTHOR]

Post-menopausal wound care management is a substantial burden on health services, since there are an increased number of elderly populations linked with age-related delayed wound healing. The controlled estrogen replacement can accelerate healing of acute cutaneous wounds, linked to its potent anti-inflammatory activity. The electrospinning technique can be used to introduce the desired therapeutic agents to the nanofiber matrix. So here we introduce a new material for wound tissue dressing, in which a polyurethane–dextran composite nanofibrous wound dressing material loaded with β-estradiol was obtained through electrospinning. Dextran can promote neovascularization and skin regeneration in chronic wounds. This study involves the characterization of these nanofibers and analysis of cell growth and proliferation to determine the efficiency of tissue regeneration on these biocomposite polymer nanofibrous scaffolds and to study the possibility of using it as a potential wound dressing material in the in vivo models. [ABSTRACT FROM AUTHOR]