Engineering Three-Dimensional-Printed Bioactive Polylactic Acid Alginate Composite Scaffolds with Antibacterial and In Vivo Osteoinductive Capacity

3D/4D printed super reconstructed foods: Characteristics, research progress, and prospects

Super reconstructed foods (SRFs) have characteristics beyond those of real system in terms of nutrition, texture, appearance, and other properties. As 3D/4D food printing technology continues to be improved in recent years, this layered manufacturing/additive manufacturing preparation technology based on food reconstruction has made it possible to continuously develop large-scale manufacture of SRFs. Compared with the traditional reconstructed foods, SRFs prepared using 3D/4D printing technologies are discussed comprehensively in this review. To meet the requirements of customers in terms of nutrition or other characteristics, multi-processing technologies are being combined with 3D/4D printing. Aspects of printing inks, product quality parameters, and recent progress in SRFs based on 3D/4D printing are assessed systematically and discussed critically. The potential for 3D/4D printed SRFs and the need for further research and developments in this area are presented and discussed critically. In addition to the natural materials which were initially suitable for 3D/4D printing, other derivative components have already been applied, which include hydrogels, polysaccharide-based materials, protein-based materials, and smart materials with distinctive characteristics. SRFs based on 3D/4D printing can retain the characteristics of deconstruction and reconstruction while also exhibiting quality parameters beyond those of the original material systems, such as variable rheological properties, on-demand texture, essential printability, improved microstructure, improved nutrition, and more appealing appearance. SRFs with 3D/4D printing are already widely used in foods such as simulated foods, staple foods, fermented foods, foods for people with special dietary needs, and foods made from food processingbyproducts.

Rising role of 3D-printing in delivery of therapeutics for infectious disease

Modern drug delivery to tackle infectious disease has drawn close to personalizing medicine for specific patient populations. Challenges include antibiotic-resistant infections, healthcare associated infections, and customizing treatments for local patient populations. Recently, 3D-printing has become a facilitator for the development of personalized pharmaceutic drug delivery systems. With a variety of manufacturing techniques, 3D-printing offers advantages in drug delivery development for controlled, fine-tuned release and platforms for different routes of administration. This review summarizes 3D-printing techniques in pharmaceutics and drug delivery focusing on treating infectious diseases, and discusses the influence of 3D-printing design considerations on drug delivery platforms targeting these diseases. Additionally, applications of 3D-printing in infectious diseases are summarized, with the goal to provide insight into how future delivery innovations may benefit from 3D-printing to address the global challenges in infectious disease.

Design of Poly(lactic) acid/gelatin core-shell bicomponent systems as a potential wound dressing material

The electrospun core-shell nanofiber has great many advantages such as different types of solvents that can be used for changing flexibility, mechanical properties, or surface chemistry of fiber. Hydrophobic Poly(lactic) acid (PLA) and hydrophilic gelatin (Gel) were electrospun by various preparation conditions to design perfect bicomponent PLA:Gel nanofiber in a core-shell structure. Solvent types, the concentration of polymeric components, flow rate, and voltage of the electrospinning process were changed to optimization of nanofiber. According to the SEM images, the best nanofiber structure without beads was obtained at 0.4 ml/h flow rate of PLA solution and 1.2 ml/h flow rate of Gel solution at 45:55 (w:w %) weight ratio of PLA:Gel in trifluoroethanol solvent with a 10 kV voltage at 10 cm distance to the collector. From the TEM images, the existence of the core-shell structure had been proved which all prepared nanofibers with 2,2,2-Trifluoroethanol solvent. Furthermore, contact angle measurements showed a change in wettability when the Gel amount was increased. Therefore, the mildest synthesis conditions were determined for bicomponent PLA:Gel core-shell nanofibers as a potential wound dressing and dual drug carrier materials.

3D Printing Applications for Craniomaxillofacial Reconstruction: A Sweeping Review

The field of craniomaxillofacial (CMF) surgery is rich in pathological diversity and broad in the ages that it treats. Moreover, the CMF skeleton is a complex confluence of sensory organs and hard and soft tissue with load-bearing demands that can change within millimeters. Computer-aided design (CAD) and additive manufacturing (AM) create extraordinary opportunities to repair the infinite array of craniomaxillofacial defects that exist because of the aforementioned circumstances. 3D printed scaffolds have the potential to serve as a comparable if not superior alternative to the "gold standard" autologous graft. In vitro and in vivo studies continue to investigate the optimal 3D printed scaffold design and composition to foster bone regeneration that is suited to the unique biological and mechanical environment of each CMF defect. Furthermore, 3D printed fixation devices serve as a patient-specific alternative to those that are available off-the-shelf with an opportunity to reduce operative time and optimize fit. Similar benefits have been found to apply to 3D printed anatomical models and surgical guides for preoperative or intraoperative use. Creation and implementation of these devices requires extensive preclinical and clinical research, novel manufacturing capabilities, and strict regulatory oversight. Researchers, manufacturers, CMF surgeons, and the United States Food and Drug Administration (FDA) are working in tandem to further the development of such technology within their respective domains, all with a mutual goal to deliver safe, effective, cost-efficient, and patient-specific CMF care. This manuscript reviews FDA regulatory status, 3D printing techniques, biomaterials, and sterilization procedures suitable for 3D printed devices of the craniomaxillofacial skeleton. It also seeks to discuss recent clinical applications, economic feasibility, and future directions of this novel technology. By reviewing the current state of 3D printing in CMF surgery, we hope to gain a better understanding of its impact and in turn identify opportunities to further the development of patient-specific surgical care.

Biocompatible Alginate Film Crosslinked with Ca2+ and Zn2+ Possesses Antibacterial, Antiviral, and Anticancer Activities

Alginate is a highly promising biopolymer due to its non-toxic and biodegradable properties. Alginate hydrogels are often fabricated by cross-linking sodium alginate with calcium cations and can be engineered with highly desirable enhanced physical and biological properties for biomedical applications. This study reports on the anticancer, antiviral, antibacterial, in vitro, and in vivo toxicity, water absorption, and compound release properties of an alginate hydrogel crosslinked with calcium and different amounts of zinc cations. The results showed that the calcium alginate hydrogel film crosslinked with the highest amount of zinc showed similar water sorption properties to those of calcium alginate and released a suitable amount of zinc to provide anticancer activity against melanoma and colon cancer cells and has antibacterial properties against methicillin-resistant Staphylococcus epidermidis and antiviral activity against enveloped and non-enveloped viruses. This film is non-toxic in both in vitro in keratinocyte HaCaT cells and in vivo in the Caenorhabditis elegans model, which renders it especially promising for biomedical applications.

Polyvinylpyrrolidone-Alginate-Carbonate Hydroxyapatite Porous Composites for Dental Applications

An alternative approach for the currently used replacement therapy in dentistry is to apply materials that restore tooth tissue. Among them, composites, based on biopolymers with calcium phosphates, and cells can be applied. In the present work, a composite based on polyvinylpyrrolidone (PVP) and alginate (Alg) with carbonate hydroxyapatite (CHA) was prepared and characterized. The composite was investigated by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance (EPR) and scanning electron microscopy methods, and the microstructure, porosity, and swelling properties of the material were described. In vitro studies included the MTT test using mouse fibroblasts, and adhesion and survivability tests with human dental pulp stem cells (DPSC). The mineral component of the composite corresponded to CHA with an admixture of amorphous calcium phosphate. The presence of a bond between the polymer matrix and CHA particles was shown by EPR. The structure of the material was represented by micro- (30-190 μm) and nano-pores (average 8.71 ± 4.15 nm). The swelling measurements attested that CHA addition increased the polymer matrix hydrophilicity by 200%. In vitro studies demonstrated the biocompatibility of PVP-Alg-CHA (95 ± 5% cell viability), and DPSC located inside the pores. It was concluded that the PVP-Alg-CHA porous composite is promising for dentistry applications.