Development of 3D Printed Drug-Eluting Scaffolds for Preventing Piercing Infection

Development of 3D-Printable Albumin-Alginate Foam for Wound Dressing Applications

In this article, a method to develop 3D printable hybrid sodium alginate and albumin foam, crosslinked with calcium chloride mist is introduced. Using this method, highly porous structures are produced without the need of further postprocessing (such as freeze drying). The proposed method is particularly beneficial in the development of wound dressing as the printed foams show excellent lift-off and water absorption properties. Compared with methods that use liquid crosslinker, the use of mist prevents the leaching of biocompounds into the liquid crosslinker. 3D printing technique was chosen to provide more versatility over the wound dressing geometry. Calcium chloride and rhodamine B were used as the crosslinking material and the model drug, respectively. Various biomaterial inks were prepared by different concentrations of sodium alginate and albumin, and the fabricated scaffolds were crosslinked in mist, liquid, or kept without crosslinking. The effects of biomaterial composition and the crosslinking density on the wound dressing properties were assessed through printability studies. The mist-crosslinked biomaterial ink composed of 1% (w/v) sodium alginate and 12% (w/v) albumin showed the superior printability. The fabricated scaffolds were also characterized through porosity, mechanical, degradation, and drug release tests. The mist-crosslinked scaffolds showed superior mechanical properties and provided relatively prolonged drug release.

Advancements in 3D-printable polysaccharides, proteins, and synthetic polymers for wound dressing and skin scaffolding - A review

This review investigates the most recent advances in personalized 3D-printed wound dressings and skin scaffolding. Skin is the largest and most vulnerable organ in the human body. The human body has natural mechanisms to restore damaged skin through several overlapping stages. However, the natural wound healing process can be rendered insufficient due to severe wounds or disturbances in the healing process. Wound dressings are crucial in providing a protective barrier against the external environment, accelerating healing. Although used for many years, conventional wound dressings are neither tailored to individual circumstances nor specific to wound conditions. To address the shortcomings of conventional dressings, skin scaffolding can be used for skin regeneration and wound healing. This review thoroughly investigates polysaccharides (e.g., chitosan, Hyaluronic acid (HA)), proteins (e.g., collagen, silk), synthetic polymers (e.g., Polycaprolactone (PCL), Poly lactide-co-glycolic acid (PLGA), Polylactic acid (PLA)), as well as nanocomposites (e.g., silver nano particles and clay materials) for wound healing applications and successfully 3D printed wound dressings. It discusses the importance of combining various biomaterials to enhance their beneficial characteristics and mitigate their drawbacks. Different 3D printing fabrication techniques used in developing personalized wound dressings are reviewed, highlighting the advantages and limitations of each method. This paper emphasizes the exceptional versatility of 3D printing techniques in advancing wound healing treatments. Finally, the review provides recommendations and future directions for further research in wound dressings.

3D printing of biologics-what has been accomplished to date?

Three-dimensional (3D) printing is a promising approach for the stabilization and delivery of non-living biologics. This versatile tool builds complex structures and customized resolutions, and has significant potential in various industries, especially pharmaceutics and biopharmaceutics. Biologics have become increasingly prevalent in the field of medicine due to their diverse applications and benefits. Stability is the main attribute that must be achieved during the development of biologic formulations. 3D printing could help to stabilize biologics by entrapment, support binding, or crosslinking. Furthermore, gene fragments could be transited into cells during co-printing, when the pores on the membrane are enlarged. This review provides: (i) an introduction to 3D printing technologies and biologics, covering genetic elements, therapeutic proteins, antibodies, and bacteriophages; (ii) an overview of the applications of 3D printing of biologics, including regenerative medicine, gene therapy, and personalized treatments; (iii) information on how 3D printing could help to stabilize and deliver biologics; and (iv) discussion on regulations, challenges, and future directions, including microneedle vaccines, novel 3D printing technologies and artificial-intelligence-facilitated research and product development. Overall, the 3D printing of biologics holds great promise for enhancing human health by providing extended longevity and enhanced quality of life, making it an exciting area in the rapidly evolving field of biomedicine.

Printable-Microencapsulated Ascorbic Acid for Personalized Topical Delivery

This study presents the successful development of printable-microencapsulated ascorbic acid (AA) for personalized topical delivery using laser printing technology. Rice flour with a 10% AA content was selected as an encapsulation material. Hydrophobic nanosilica was used to create negative electrostatic charges on the microencapsulated surfaces via a high-speed mixture. This process facilitated the microencapsulated AA fabrication using a commercial laser printer and produced a well-patterned design with some minor print defects, such as banding and scattering. The amount of encapsulated AA per area was 0.28 mg/cm2, and the RGB color code was 0,0,0. An emulsion carrier system comprising pentylene glycol (P5G) or diethylene glycol monoethyl ether (DEGEE), Tween 20, oleic acid, and deionized (DI) water at a ratio of 20:30:30:20 was developed to enhance AA transmission into the skin. The Franz diffusion cell technique was used to investigate topical absorption on Strat-M membranes using P5G and DEGEE as enhancers. The steady-state fluxes were 8.40 (±0.64) and 10.04 (±0.58) μg/h/cm2 for P5G and DEGEE, respectively. Cytotoxicity tests conducted on fibroblast cells revealed low cytotoxicity for the encapsulation products and carriers.

Cartilage's Contribution in Otology: A Comprehensive Review of Its Role in Ear Surgery

This comprehensive review thoroughly examines the pivotal role of cartilage in otologic surgery, elucidating its multifaceted contributions to both cosmetic and functional outcomes. From reconstructing the external ear to reinforcing the tympanic membrane and restoring the ossicular chain, cartilage emerges as a versatile and resilient biological material with unique properties that make it an invaluable resource for otologic surgeons. The review explores the nuances of cartilage's applications in various surgical contexts, emphasizing its significance in promoting tissue regeneration and healing. The text delves into advancements in tissue engineering, biodegradable scaffolds, and 3D printing technology, pointing toward a future where more precise and personalized interventions may redefine the landscape of otologic surgery. The convergence of these innovations holds the promise of elevating the standard of care, minimizing complications, and improving the quality of life for patients undergoing cartilage-based otologic procedures. This synthesis of current knowledge and future possibilities provides a valuable resource for otologists, surgeons, and researchers in the dynamic field of otology.

3D Printed Materials for Combating Antimicrobial Resistance

Three-dimensional (3D) printing is a rapidly growing technology with a significant capacity for translational applications in both biology and medicine. 3D-printed living and non-living materials are being widely tested as a potential replacement for conventional solutions for testing and combating antimicrobial resistance (AMR). The precise control of cells and their microenvironment, while simulating the complexity and dynamics of an in vivo environment, provides an excellent opportunity to advance the modeling and treatment of challenging infections and other health conditions. 3D-printing models the complicated niches of microbes and host-pathogen interactions, and most importantly, how microbes develop resistance to antibiotics. In addition, 3D-printed materials can be applied to testing and delivering antibiotics. Here, we provide an overview of 3D printed materials and biosystems and their biomedical applications, focusing on ever increasing AMR. Recent applications of 3D printing to alleviate the impact of AMR, including developed bioprinted systems, targeted bacterial infections, and tested antibiotics are presented.

Ear-piercing complications in children and adolescents

QUESTION

Ear piercing is one of the most common forms of body modification seen in children and adolescents presenting to my office. Parents of my younger pediatric patients inquire about potential post-piercing complications and risk factors associated with earlobe infections. What guidance should I give them? Also, are there any specific post-piercing complications to consider for older pediatric patients seeking second piercings in the upper cartilage area?

ANSWER

Piercing the earlobe or auricular cartilage continues to be a popular procedure among children and adolescents. Despite its widespread practice, improper aseptic piercing technique, insufficient training, and trauma to the soft tissue during high-pressure piercing (eg, use of spring-loaded ear-piercing instruments) can increase one's susceptibility to infections, bleeding, and microfractures. Other post-piercing complications include embedded earrings, keloids, hypertrophic scarring, and cutaneous hypersensitivity. Early recognition and treatment of infections and perichondritis secondary to transcartilaginous piercings can prevent the progression of severe ear deformities requiring reconstructive surgical interventions.

3D Printing: An Emerging Technology for Biocatalyst Immobilization

Employment of enzymes as biocatalysts offers immense benefits across diverse sectors in the context of green chemistry, biodegradability, and sustainability. When compared to free enzymes in solution, enzyme immobilization proposes an effective means of improving functional efficiency and operational stability. The advance of printable and functional materials utilized in additive manufacturing, coupled with the capability to produce bespoke geometries, has sparked great interest towards the 3D printing of immobilized enzymes. Printable biocatalysts represent a new generation of enzyme immobilization in a more customizable and adaptable manner, unleashing their potential functionalities for countless applications in industrial biotechnology. This review provides an overview of enzyme immobilization techniques and 3D printing technologies, followed by illustrations of the latest 3D printed enzyme-immobilized industrial and clinical applications. The unique advantages of harnessing 3D printing as an enzyme immobilization technique will be presented, alongside a discussion on its potential limitations. Finally, the future perspectives of integrating 3D printing with enzyme immobilization will be considered, highlighting the endless possibilities that are achievable in both research and industry. This article is protected by copyright. All rights reserved.

Additive Manufacturing Strategies for Personalized Drug Delivery Systems and Medical Devices: Fused Filament Fabrication and Semi Solid Extrusion

Novel additive manufacturing (AM) techniques and particularly 3D printing (3DP) have achieved a decade of success in pharmaceutical and biomedical fields. Highly innovative personalized therapeutical solutions may be designed and manufactured through a layer-by-layer approach starting from a digital model realized according to the needs of a specific patient or a patient group. The combination of patient-tailored drug dose, dosage, or diagnostic form (shape and size) and drug release adjustment has the potential to ensure the optimal patient therapy. Among the different 3D printing techniques, extrusion-based technologies, such as fused filament fabrication (FFF) and semi solid extrusion (SSE), are the most investigated for their high versatility, precision, feasibility, and cheapness. This review provides an overview on different 3DP techniques to produce personalized drug delivery systems and medical devices, highlighting, for each method, the critical printing process parameters, the main starting materials, as well as advantages and limitations. Furthermore, the recent developments of fused filament fabrication and semi solid extrusion 3DP are discussed. In this regard, the current state of the art, based on a detailed literature survey of the different 3D products printed via extrusion-based techniques, envisioning future directions in the clinical applications and diffusion of such systems, is summarized.

Natural Hydrogel-Based Bio-Inks for 3D Bioprinting in Tissue Engineering: A Review

Three-dimensional (3D) printing is well acknowledged to constitute an important technology in tissue engineering, largely due to the increasing global demand for organ replacement and tissue regeneration. In 3D bioprinting, which is a step ahead of 3D biomaterial printing, the ink employed is impregnated with cells, without compromising ink printability. This allows for immediate scaffold cellularization and generation of complex structures. The use of cell-laden inks or bio-inks provides the opportunity for enhanced cell differentiation for organ fabrication and regeneration. Recognizing the importance of such bio-inks, the current study comprehensively explores the state of the art of the utilization of bio-inks based on natural polymers (biopolymers), such as cellulose, agarose, alginate, decellularized matrix, in 3D bioprinting. Discussions regarding progress in bioprinting, techniques and approaches employed in the bioprinting of natural polymers, and limitations and prospects concerning future trends in human-scale tissue and organ fabrication are also presented.

3D-Printed Products for Topical Skin Applications: From Personalized Dressings to Drug Delivery

3D printing has been widely used for the personalization of therapies and on-demand production of complex pharmaceutical forms. Recently, 3D printing has been explored as a tool for the development of topical dosage forms and wound dressings. Thus, this review aims to present advances related to the use of 3D printing for the development of pharmaceutical and biomedical products for topical skin applications, covering plain dressing and products for the delivery of active ingredients to the skin. Based on the data acquired, the important growth in the number of publications over the last years confirms its interest. The semisolid extrusion technique has been the most reported one, probably because it allows the use of a broad range of polymers, creating the most diverse therapeutic approaches. 3D printing has been an excellent field for customizing dressings, according to individual needs. Studies discussed here imply the use of metals, nanoparticles, drugs, natural compounds and proteins and peptides for the treatment of wound healing, acne, pain relief, and anti-wrinkle, among others. The confluence of 3D printing and topical applications has undeniable advantages, and we would like to encourage the research groups to explore this field to improve the patient's life quality, adherence and treatment efficacy.

Development of N,O-Carboxymethyl Chitosan-Starch Biomaterial Inks for 3D Printed Wound Dressing Applications

In this paper, a novel hybrid biomaterial ink consisting of two water-soluble polymers is investigated: starch and N,O-carboxymethyl chitosan (NOCC). The biomaterial ink is used to fabricate controlled release biodegradable wound dressing scaffolds via a novel low-temperature solvent (organic)-free 3D printing technique. NOCC is a variant of chitosan with a high degradation rate that can lead to an immediate release of the drugs, and starch, on the other hand, is used to alter degradation and drug release characteristics of the biomaterial. Mupirocin, a topical anti-infective, is incorporated into the biomaterial inks. Different biomaterial inks in terms of NOCC to starch ratio are prepared and characterized. Printability and rheology of the samples are investigated, and the release of mupirocin over time is quantified. The efficacy of the developed 3D printed wound dressings against Staphylococcus aureus is examined through disk diffusion assays. Increasing NOCC accelerated the release of the drug from the scaffold and led to larger zones of inhibition in the early hours of the in vitro tests; this phenomenon is correlated to the enhanced hydrophilicity of NOCC-dominated scaffolds. The drug release and the zone of inhibition are controlled by altering starch to NOCC ratio in the biomaterial ink.

3D Printing of Thermo-Sensitive Drugs

Three-dimensional (3D) printing is among the rapidly evolving technologies with applications in many sectors. The pharmaceutical industry is no exception, and the approval of the first 3D-printed tablet (Spiratam^®) marked a revolution in the field. Several studies reported the fabrication of different dosage forms using a range of 3D printing techniques. Thermosensitive drugs compose a considerable segment of available medications in the market requiring strict temperature control during processing to ensure their efficacy and safety. Heating involved in some of the 3D printing technologies raises concerns regarding the feasibility of the techniques for printing thermolabile drugs. Studies reported that semi-solid extrusion (SSE) is the commonly used printing technique to fabricate thermosensitive drugs. Digital light processing (DLP), binder jetting (BJ), and stereolithography (SLA) can also be used for the fabrication of thermosensitive drugs as they do not involve heating elements. Nonetheless, degradation of some drugs by light source used in the techniques was reported. Interestingly, fused deposition modelling (FDM) coupled with filling techniques offered protection against thermal degradation. Concepts such as selection of low melting point polymers, adjustment of printing parameters, and coupling of more than one printing technique were exploited in printing thermosensitive drugs. This systematic review presents challenges, 3DP procedures, and future directions of 3D printing of thermo-sensitive formulations.

Semi-solid extrusion 3D printing in drug delivery and biomedicine: Personalised solutions for healthcare challenges

Three-dimensional (3D) printing is an innovative additive manufacturing technology, capable of fabricating unique structures in a layer-by-layer manner. Semi-solid extrusion (SSE) is a subset of material extrusion 3D printing, and through the sequential deposition of layers of gel or paste creates objects of any desired size and shape. In comparison to other extrusion-based technologies, SSE 3D printing employs low printing temperatures which makes it suitable for drug delivery and biomedical applications, and the use of disposable syringes provides benefits in meeting critical quality requirements for pharmaceutical use. Besides pharmaceutical manufacturing, SSE 3D printing has attracted increasing attention in the field of bioelectronics, particularly in the manufacture of biosensors capable of measuring physiological parameters or as a means to trigger drug release from medical devices. This review begins by highlighting the major printing process parameters and material properties that influence the feasibility of transforming a 3D design into a 3D object, and follows with a discussion on the current SSE 3D printing developments and their applications in the fields of pharmaceutics, bioprinting and bioelectronics. Finally, the advantages and limitations of this technology are explored, before focusing on its potential clinical applications and suitability for preparing personalised medicines.