Extruded filaments derived 3D printed medicated skin patch to mitigate destructive pulmonary tuberculosis: design to delivery

Development and evaluation of hot-melt-extruded diquafosol tetrasodium formulations for ophthalmic inserts: A design of experiments approach

This study aimed to develop, optimize, and evaluate hot-melt-extruded ophthalmic inserts capable of sustained release of diquafosol tetrasodium (DQS) via a design of experiments approach. DQS, a tear stimulant for dry eye management, faces challenges of frequent administration and low bioavailability. The developed insert uses biodegradable polymers in varied proportions to achieve sustained release. Optimized through mixture design, the insert completely dissolved within 24 h and maintained a stable drug content, thickness, and surface pH over three months at room temperature. In vitro corneal permeation studies on excised rabbit corneas demonstrated increased bioavailability, suggesting a reduced dosing frequency compared with conventional eye drops. Therefore, this insert has potential to enhance treatment outcomes by improving patient compliance and providing sustained drug effects.

The advances in adjuvant therapy for tuberculosis with immunoregulatory compounds

Tuberculosis (TB) is a chronic bacterial disease, as well as a complex immune disease. The occurrence, development, and prognosis of TB are not only related to the pathogenicity of Mycobacterium tuberculosis (Mtb), but also related to the patient's own immune state. The research and development of immunotherapy drugs can effectively regulate the body's anti-TB immune responses, inhibit or eliminate Mtb, alleviate pathological damage, and facilitate rehabilitation. This paper reviews the research progress of immunotherapeutic compounds for TB, including immunoregulatory compounds and repurposing drugs, and points out the existing problems and future research directions, which lays the foundation for studying new agents for host-directed therapies of TB.

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.

Facile fabrication of an extended-release tablet of Ticagrelor using three dimensional printing technology

The objective of the study was to fabricate tailored extended-release tablets of blood thinner Ticagrelor as once-daily dosing using additive manufacturing for better compliance in heart failure therapy. The solid work design of the tablet was printed using hot melt extrusion (HME) based 3D printing by optimized mixture of Eudragit RS-100, plasticizer and drug for producing extrudable and printable filaments. FTIR and TGA results showed no covalent interaction among ingredients and no decomposition during HME process, respectively. Friability, weight variation, assay and content uniformity tests met USP requirements, while the mean hardness of the tablets was calculated in a value between 40 and 50 kg. According to DSC and XRD results, the crystallinity state of the Ticagrelor was converted to an amorphous one in the tablet matrix. Smooth surfaces with multiple deposited layers were observed using SEM. In comparison, the maximum Ticagrelor release of 100% after 120 min from Brilinta® tablets was decreased to 97% in 400 min from the 3D tablet at infill of 90%. Korsmeyer-Peppas kinetic model showed the drug release mechanism is affected by diffusion and swelling. In general, fabrication of the extended-release 3D printed tablet of Ticagrelor using HME-based-additive manufacturing has the potential to provide specific doses with tailored kinetic release for personalized medicine, improving adherence at point-of-care.

Fused Deposition Modelling 3D printing and solubility improvement of BCS II and IV active ingredients - A narrative review

In the field of pharmaceutical research and development, Fused Deposition Modelling (FDM) 3D printing (3DP) has aroused growing interest within the last ten years. The use of thermoplastic polymers, combined with the melting process of the raw materials, offers the possibility of manufacturing amorphous solid dispersions (ASDs). In the pharmaceutical industry, the formulation of an ASD is a widely used strategy to improve the solubility of poorly soluble drugs (classified by the Biopharmaceutical Classification System (BCS) as class II and IV). In this review, an analysis of studies that have developed a FDM printed form containing a BCS class II or IV active substance was performed. The focus has been placed on the evaluation of the solid state of the active molecules (crystalline or amorphous) and on the study of their dissolution profile. Thus, the aim of this work is to highlight the interest of FDM 3DP to induce the amorphisation phenomenon of Class II and IV active substances by forming an ASD, and as result improving their solubility.

Advanced drug delivery and therapeutic strategies for tuberculosis treatment

Tuberculosis (TB) remains a significant global health challenge, necessitating innovative approaches for effective treatment. Conventional TB therapy encounters several limitations, including extended treatment duration, drug resistance, patient noncompliance, poor bioavailability, and suboptimal targeting. Advanced drug delivery strategies have emerged as a promising approach to address these challenges. They have the potential to enhance therapeutic outcomes and improve TB patient compliance by providing benefits such as multiple drug encapsulation, sustained release, targeted delivery, reduced dosing frequency, and minimal side effects. This review examines the current landscape of drug delivery strategies for effective TB management, specifically highlighting lipid nanoparticles, polymer nanoparticles, inorganic nanoparticles, emulsion-based systems, carbon nanotubes, graphene, and hydrogels as promising approaches. Furthermore, emerging therapeutic strategies like targeted therapy, long-acting therapeutics, extrapulmonary therapy, phototherapy, and immunotherapy are emphasized. The review also discusses the future trajectory and challenges of developing drug delivery systems for TB. In conclusion, nanomedicine has made substantial progress in addressing the challenges posed by conventional TB drugs. Moreover, by harnessing the unique targeting abilities, extended duration of action, and specificity of advanced therapeutics, innovative solutions are offered that have the potential to revolutionize TB therapy, thereby enhancing treatment outcomes and patient compliance.

Extrusion-based systems for topical and transdermal drug delivery

INTRODUCTION

Although the administration of drugs on the skin is a safe and noninvasive therapeutic alternative, producing formulations capable of disrupting the cutaneous barriers is still a challenge. In this scenario, extrusion-based techniques have emerged as disruptive technologies to ensure unique drug-excipient interactions that facilitate drug skin diffusion for systemic or local effect and even mean the key to obtain viable industrial products.

AREAS COVERED

This article presents a comprehensive overview of extrusion-based techniques in developing pharmaceutical dosage forms for topical or transdermal drug delivery. First, the theoretical basis of how extrusion-based techniques can optimize the permeation of drugs through the skin is examined. Then, the current state-of-the-art of drug products developed by extrusion-based techniques, specifically by hot-melt extrusion (HME) and fused deposition modeling (FDM) 3D printing, are discussed and contrasted with the current pharmaceutical processes.

EXPERT OPINION

A wide variety of pharmaceutical products can be obtained using HME and FDM 3D printing, including new dosage forms designed for a perfect anatomical fit. Despite the limitations of pharmaceutical products produced with HME and FDM 3D printing regarding thermal stability and available excipients, the advantages in industrial adaptability and improved bioavailability allied with patient-match devices certainly deserve full attention and investment.

3D Printed Housing Devices for Segregated Compartmental Delivery of Oral Fixed-Dose Anti-Tubercular Drugs Adopting Print and Fill Strategy

World Health Organization (WHO) recommends the use of first-line anti-tuberculosis drugs, that is, rifampicin (RIF) and isoniazid (INH) fixed-dose combination (FDC) therapies in tuberculosis (TB) disease. The absorption of RIF from an FDC incorporates INH, and it is significantly compromised due to its reaction with INH, resulting in a severe loss of RIF under gastric stomach pH condition. Such reduction in the dose of both drugs from FDC formulations has been alleged to be one of the chief obstacles in effective TB treatment. This emphasizes a need to develop suitable cutting-edge advanced bioengineered delivery devices that can attenuate this severe problem to mitigate this chief obstacle. Therefore, we designed, prototyped, and characterized bioengineered 3D printed housing devices in the form of printed tablets adopting print and fill strategy for segregated compartmental delivery of RIF into the intestine (to avoid stomach gastric pH induced chemical degradation as alone and FDC) and INH into the stomach (no degradation observed as alone and FDC in stomach gastric pH conditions) for the desired treatment outcome against TB. Prepared 3D printed housings showed almost zero friability, enough hardness along weight variations <±3.0%. Different thermal and morphological analyses confirmed the insignificant changes in the nature of the polymer as before and after printing. The in vitro release for INH from polyvinyl alcohol mediated 3D printed housings showed almost 100% release within 2.5 h in acidic medium, whereas poly-lactic acid (PLA) mediated 3D printed housings continued to release RIF above 70% in the presence of physiological enzymes in alkaline medium for 432 h. The in vivo bioavailability assessment correlated with in vitro dissolution behavior for INH and RIF, whereas RIF did not release from 3D printed PLA housings in vivo.

Promising bioactive properties of quercetin for potential food applications and health benefits: A review

Naturally occurring phytochemicals with promising biological properties are quercetin and its derivatives. Quercetin has been thoroughly studied for its antidiabetic, antibacterial, anti-inflammatory, anti-Alzheimer's, anti-arthritic, antioxidant, cardiovascular, and wound-healing properties. Anticancer activity of quercetin against cancer cell lines has also recently been revealed. The majority of the Western diet contains quercetin and its derivatives, therefore consuming them as part of a meal or as a food supplement may be sufficient for people to take advantage of their preventive effects. Bioavailability-based drug-delivery systems of quercetin have been heavily studied. Fruits, seeds, vegetables, bracken fern, coffee, tea, and other plants all contain quercetin, as do natural colors. One naturally occurring antioxidant is quercetin, whose anticancer effects have been discussed in detail. It has several properties that could make it an effective anti-cancer agent. Numerous researches have shown that quercetin plays a substantial part in the suppression of cancer cells in the breast, colon, prostate, ovary, endometrial, and lung tumors. The current study includes a concise explanation of quercetin's action mechanism and potential health applications.

Customized 3D-printed hollow capsular device filled with norfloxacin-loaded micropellets for controlled-release delivery

Pharmacotherapy has become more focused on the personalized treatment of patients with various diseases. This field of pharmacology and pharmacogenomics focuses on developing drug delivery systems designed to address the unique characteristics of individual patients. Three-dimensional printing technology can be used to fabricate personalized drug delivery systems with desired release properties according to patient needs. Norfloxacin (NOR)-loaded micropellets (MPs) were fabricated and filled inside a stereolithography (SLA) 3D printing technology-mediated hollow capsular device in accordance with a standard size of 09 (8.4 mm length × 2.70 mm diameter). The prepared 3D-printed hollow capsular device filled with pristine NOR and NOR-loaded MPs were characterized in terms of both in vitro and in vivo means. MPs with the particle size distribution of 1540.0 ± 26 µm showed 95.63 ± 2.0% NOR content with pellet-shaped surface morphology. The in vitro release profile showed an initial lag phase of approximately 30 min, followed by the sustained release of NOR from MPs from the 3D-printed hollow capsular device. The pharmacokinetic profile showed prolonged T_max, AUC, and evidence of good RBA of NOR compared to pure NOR after a single oral administration in the experimental animal model. The overall results confirm the feasibility of SLA-mediated 3D printing technology for preparing customized solid oral unit dosage carriers that can be filled with pure NOR- and NOR-loaded MPs with controlled-release delivery features.

The Evolution of the 3D-Printed Drug Delivery Systems: A Review

Since the appearance of the 3D printing in the 1980s it has revolutionized many research fields including the pharmaceutical industry. The main goal is to manufacture complex, personalized products in a low-cost manufacturing process on-demand. In the last few decades, 3D printing has attracted the attention of numerous research groups for the manufacturing of different drug delivery systems. Since the 2015 approval of the first 3D-printed drug product, the number of publications has multiplied. In our review, we focused on summarizing the evolution of the produced drug delivery systems in the last 20 years and especially in the last 5 years. The drug delivery systems are sub-grouped into tablets, capsules, orodispersible films, implants, transdermal delivery systems, microneedles, vaginal drug delivery systems, and micro- and nanoscale dosage forms. Our classification may provide guidance for researchers to more easily examine the publications and to find further research directions.

Traction of 3D and 4D Printing in the Healthcare Industry: From Drug Delivery and Analysis to Regenerative Medicine

Three-dimensional (3D) printing and 3D bioprinting are promising technologies for a broad range of healthcare applications from frontier regenerative medicine and tissue engineering therapies to pharmaceutical advancements yet must overcome the challenges of biocompatibility and resolution. Through comparison of traditional biofabrication methods with 3D (bio)printing, this review highlights the promise of 3D printing for the production of on-demand, personalized, and complex products that enhance the accessibility, effectiveness, and safety of drug therapies and delivery systems. In addition, this review describes the capacity of 3D bioprinting to fabricate patient-specific tissues and living cell systems (e.g., vascular networks, organs, muscles, and skeletal systems) as well as its applications in the delivery of cells and genes, microfluidics, and organ-on-chip constructs. This review summarizes how tailoring selected parameters (i.e., accurately selecting the appropriate printing method, materials, and printing parameters based on the desired application and behavior) can better facilitate the development of optimized 3D-printed products and how dynamic 4D-printed strategies (printing materials designed to change with time or stimulus) may be deployed to overcome many of the inherent limitations of conventional 3D-printed technologies. Comprehensive insights into a critical perspective of the future of 4D bioprinting, crucial requirements for 4D printing including the programmability of a material, multimaterial printing methods, and precise designs for meticulous transformations or even clinical applications are also given.

Beneath the Skin: A Review of Current Trends and Future Prospects of Transdermal Drug Delivery Systems

The ideal drug delivery system has a bioavailability comparable to parenteral dosage forms but is as convenient and easy to use for the patient as oral solid dosage forms. In recent years, there has been increased interest in transdermal drug delivery (TDD) as a non-invasive delivery approach that is generally regarded as being easy to administer to more vulnerable age groups, such as paediatric and geriatric patients, while avoiding certain bioavailability concerns that arise from oral drug delivery due to poor absorbability and metabolism concerns. However, despite its many merits, TDD remains restricted to a select few drugs. The physiology of the skin poses a barrier against the feasible delivery of many drugs, limiting its applicability to only those drugs that possess physicochemical properties allowing them to be successfully delivered transdermally. Several techniques have been developed to enhance the transdermal permeability of drugs. Both chemical (e.g., thermal and mechanical) and passive (vesicle, nanoparticle, nanoemulsion, solid dispersion, and nanocrystal) techniques have been investigated to enhance the permeability of drug substances across the skin. Furthermore, hybrid approaches combining chemical penetration enhancement technologies with physical technologies are being intensively researched to improve the skin permeation of drug substances. This review aims to summarize recent trends in TDD approaches and discuss the merits and drawbacks of the various chemical, physical, and hybrid approaches currently being investigated for improving drug permeability across the skin.

Development and Validation of a Novel Tool for Assessing the Environmental Impact of 3D Printing Technologies: A Pharmaceutical Perspective

Technological advancements have created infinite opportunities and rendered our life easier at several fronts. Nonetheless, the environment has suffered the aftermaths of modernization. Ironically, the pharmaceutical industry was found to be a significant contributor to environmental deterioration. To tackle this issue, continuous eco-evaluation of newly introduced technologies is crucial. Three-dimensional printing (3DP) is rapidly establishing its routes in different industries. Interestingly, 3DP is revolutionising the production of pharmaceuticals and is regarded as a promising approach for the fabrication of patient-centric formulations. Despite the increasing applications in the pharmaceutical field, tools that evaluate the environmental impacts of 3DP are lacking. Energy and solvent consumption, waste generation, and disposal are the main associated factors that present major concerns. For the first time, we are proposing a quantitative tool, the index of Greenness Assessment of Printed Pharmaceuticals (iGAPP), that evaluates the greenness of the different 3DP technologies used in the pharmaceutical industry. The tool provides a colour-coded pictogram and a numerical score indicating the overall greenness of the employed printing method. Validation was performed by constructing the greenness profile of selected formulations produced using the different 3DP techniques. This tool is simple to use and indicates the greenness level of the procedures involved, thereby creating an opportunity to modify the processes for more sustainable practices.

Fabrication and In Vitro/Vivo Evaluation of Drug Nanocrystals Self-Stabilized Pickering Emulsion for Oral Delivery of Quercetin

The aim of this study was to develop a new drug nanocrystals self-stabilized Pickering emulsion (NSSPE) for improving oral bioavailability of quercetin (QT). Quercetin nanocrystal (QT–NC) was fabricated by high pressure homogenization method, and QT–NSSPE was then prepared by ultrasound method with QT–NC as solid particle stabilizer and optimized by Box-Behnken design. The optimized QT–NSSPE was characterized by fluorescence microscope (FM), scanning electron micrograph (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The stability, in vitro release, and in vivo oral bioavailability of QT–NSSPE were also investigated. Results showed that the droplets of QT–NSSPE with the size of 10.29 ± 0.44 μm exhibited a core-shell structure consisting of a core of oil and a shell of QT–NC. QT–NSSPE has shown a great stability in droplets shape, size, creaming index, zeta potential, and QT content during 30 days storage at 4, 25, and 40 °C. In vitro release studies showed that QT–NSSPE performed a better dissolution behavior (65.88% within 24 h) as compared to QT–NC (50.71%) and QT coarse powder (20.15%). After oral administration, the AUC_0–t of QT–NSSPE was increased by 2.76-times and 1.38 times compared with QT coarse powder and QT–NC. It could be concluded that NSSPE is a promising oral delivery system for improving the oral bioavailability of QT.

Partial Biodegradable Blend for Fused Filament Fabrication: In-Process Thermal and Post-Printing Moisture Resistance

Despite the extensive research, the moisture-based degradation of the 3D-printed polypropylene and polylactic acid blend is not yet reported. This research is a part of study reported on partial biodegradable blends proposed for large-scale additive manufacturing applications. However, the previous work does not provide information about the stability of the proposed blend system against moisture-based degradation. Therefore, this research presents a combination of excessive physical interlocking and minimum chemical grafting in a partial biodegradable blend to achieve stability against in-process thermal and moisture-based degradation. In this regard, a blend of polylactic acid and polypropylene compatibilized with polyethylene graft maleic anhydride is presented for fused filament fabrication. The research implements, for the first time, an ANOVA for combined thermal and moisture-based degradation. The results are explained using thermochemical and microscopic techniques. Scanning electron microscopy is used for analyzing the printed blend. Fourier transform infrared spectroscopy has allowed studying the intermolecular interactions due to the partial blending and degradation mechanism. Differential scanning calorimetry analyzes the blending (physical interlocking or chemical grafting) and thermochemical effects of the degradation mechanism. The thermogravimetric analysis further validates the physical interlocking and chemical grafting. The novel concept of partial blending with excessive interlocking reports high mechanical stability against moisture-based degradation.

3D printing of nanocomposite pills through desktop vat photopolymerization (stereolithography) for drug delivery reasons

Background

The desktop vat polymerization process or stereolithography printing is an ideal approach to develop multifunctional nanocomposites wherein a conventional solid dosage form is used as a reservoir for compliant administration of drug-loaded nanocarriers.

Methods

In this study, a nanocomposite drug delivery system, that is, hydrogel nanoparticles of an approved nutraceutical, berberine entrapped within vat photopolymerized monoliths, was developed for drug delivery applications. For the fabrication of the nanocomposite drug delivery systems/pills, a biocompatible vat photopolymerized resin was selected as an optimum matrix capable of efficiently delivering berberine from stereolithography mediated 3D printed nanocomposite pill.

Results

The obtained data reflected the efficient formation of berberine-loaded hydrogel nanoparticles with a mean particle diameter of 95.05 ± 4.50 nm but low loading. Stereolithography-assisted fabrication of monoliths was achieved with high fidelity (in agreement with computer-aided design), and photo-crosslinking was ascertained through Fourier-transform infrared spectroscopy. The hydrogel nanoparticles were entrapped within the pills during the stereolithography process, as evidenced by electron microscopy. The nanocomposite pills showed a higher swelling in an acidic environment and consequently faster berberine release of 50.39 ± 3.44% after 4 h. The overall results suggested maximal release within the gastrointestinal transit duration and excretion of the exhausted pills.

Conclusions

We intended to demonstrate the feasibility of making 3D printed nanocomposite pills achieved through the desktop vat polymerization process for drug delivery applications.

Stereolithography-assisted fabrication of 3D printed polymeric film for topical berberine delivery: in-vitro, ex-vivo and in-vivo investigations

OBJECTIVES

3D printed polymeric film intended for topical delivery of berberine (BBR) was developed using stereolithography (SLA) to enhance its local concentrations. PEGDMA was utilized as photopolymerizing resin, with PEG 400 as an inert component to facilitate BBR solubilization and permeation.

METHODS

Three batches of topical films were printed by varying resin and PEG 400 compositions. In-vitro physicochemical characterizations of the 3D printed films were performed using several analytical techniques including ex-vivo drug permeation studies. In-vivo skin irritation studies were also conducted to assess the skin irritation potential.

KEY FINDINGS

Films were 3D printed according to design specifications with minimal variations. Microscopic analysis confirmed 3D architecture, while thermal and X-ray diffraction studies revealed amorphous BBR entrapment. Drug permeation study showed effective ex-vivo diffusion up to 344.32 ± 61.20 µg/cm2 after 24.0 h possessing a higher ratio of PEG 400. In-vivo skin irritation studies have suggested the non-irritant nature of printed films.

CONCLUSIONS

Results indicated the suitability of SLA 3D printing for topical application in the treatment of skin diseases. The presence of PEG 400 in the printed 3D films facilitated BBR diffusion, resulting in an improved flux in ex-vivo model and non-irritant properties in vivo.

The Research Progress in Immunotherapy of Tuberculosis

Tuberculosis (TB) is a serious public health problem worldwide. The combination of various anti-TB drugs is mainly used to treat TB in clinical practice. Despite the availability of effective antibiotics, effective treatment regimens still require long-term use of multiple drugs, leading to toxicity, low patient compliance, and the development of drug resistance. It has been confirmed that immune recognition, immune response, and immune regulation of Mycobacterium tuberculosis (Mtb) determine the occurrence, development, and outcome of diseases after Mtb infection. The research and development of TB-specific immunotherapy agents can effectively regulate the anti-TB immune response and provide a new approach toward the combined treatment of TB, thereby preventing and intervening in populations at high risk of TB infection. These immunotherapy agents will promote satisfactory progress in anti-TB treatment, achieving the goal of "ultra-short course chemotherapy." This review highlights the research progress in immunotherapy of TB, including immunoreactive substances, tuberculosis therapeutic vaccines, chemical agents, and cellular therapy.

Partial Polymer Blend for Fused Filament Fabrication with High Thermal Stability

The materials for large scale fused filament fabrication (FFF) are not yet designed to resist thermal degradation. This research presents a novel polymer blend of polylactic acid with polypropylene for FFF, purposefully designed with minimum feasible chemical grafting and overwhelming physical interlocking to sustain thermal degradation. Multi-level general full factorial ANOVA is performed for the analysis of thermal effects. The statistical results are further investigated and validated using different thermo-chemical and visual techniques. For example, Fourier transform infrared spectroscopy (FTIR) analyzes the effects of blending and degradation on intermolecular interactions. Differential scanning calorimetry (DSC) investigates the nature of blending (grafting or interlocking) and effects of degradation on thermal properties. Thermogravimetric analysis (TGA) validates the extent of chemical grafting and physical interlocking detected in FTIR and DSC. Scanning electron microscopy (SEM) is used to analyze the morphology and phase separation. The novel approach of overwhelmed physical interlocking and minimum chemical grafting for manufacturing 3D printing blends results in high structural stability (mechanical and intermolecular) against thermal degradation as compared to neat PLA.

Eudragit®: A Versatile Family of Polymers for Hot Melt Extrusion and 3D Printing Processes in Pharmaceutics

Eudragit® polymers are polymethacrylates highly used in pharmaceutics for the development of modified drug delivery systems. They are widely known due to their versatility with regards to chemical composition, solubility, and swelling properties. Moreover, Eudragit polymers are thermoplastic, and their use has been boosted in some production processes, such as hot melt extrusion (HME) and fused deposition modelling 3D printing, among other 3D printing techniques. Therefore, this review covers the studies using Eudragit polymers in the development of drug delivery systems produced by HME and 3D printing techniques over the last 10 years. Eudragit E has been the most used among them, mostly to formulate immediate release systems or as a taste-masker agent. On the other hand, Eudragit RS and Eudragit L100-55 have mainly been used to produce controlled and delayed release systems, respectively. The use of Eudragit polymers in these processes has frequently been devoted to producing solid dispersions and/or to prepare filaments to be 3D printed in different dosage forms. In this review, we highlight the countless possibilities offered by Eudragit polymers in HME and 3D printing, whether alone or in blends, discussing their prominence in the development of innovative modified drug release systems.

3D printing and enteric coating of a hollow capsular device with controlled drug release characteristics prepared using extruded Eudragit® filaments

This work focuses on the extrusion of a brittle, tacky, cationic copolymer i.e. Eudragit® E-100 to prepare filament and subsequent 3D printing of hollow capsular device using the extruded filament. An optimum amount of talc and triethyl citrate was used for the possible extrusion of the polymer. There was no thermal and chemical degradation of the polymer observed after extrusion confirmed by DSC and FTIR analysis. Microscopic analysis of the printed capsule showed the layer-by-layer manner of 3D printing. Capsule parts were printed according to the set dimensions (00 size) with minimal deviation. Printed capsule showed the soluble behaviour in gastric fluid pH 1.2 where within 15 min the encapsulated drug encounters with the dissolution medium and almost 70% drug was dissolved within 4 hr. In case of phosphate buffer pH 6.8, the printed capsule showed a longed swelling behaviour up to 12 hr and then gradually bursting of capsule occurred wherein more than 90% encapsulated drug was dissolved within 36 hr. Enteric coating of the printed capsule showed similar behaviour in alkaline medium that observed with non-enteric capsule. This indicates the potential application of this printed capsules for both gastric and intestinal specific delayed drug delivery by a single step enteric coating process.

Opportunities and challenges of three-dimensional printing technology in pharmaceutical formulation development

Three-dimensional printing is a technology that prints the products layer-by-layer, in which materials are deposited according to the digital model designed by computer aided design (CAD) software. This technology has competitive advantages regarding product design complexity, product personalization, and on-demand manufacturing. The emergence of 3D technology provides innovative strategies and new ways to develop novel drug delivery systems. This review summarizes the application of 3D printing technologies in the pharmaceutical field, with an emphasis on the advantages of 3D printing technologies for achieving rapid drug delivery, personalized drug delivery, compound drug delivery and customized drug delivery. In addition, this article illustrates the limitations and challenges of 3D printing technologies in the field of pharmaceutical formulation development.

3D printing of immediate-release tablets containing olanzapine by filaments extrusion

In this work, hot-melt extrusion (HME) is coupled with fused deposition modeling (FDM) mediated 3D printing to demonstrate additive manufacturing to fabricate immediate release (IR) prototypes of olanzapine with the aim of enhanced solubility using a fast disintegrating polymer (Kollicoat^® IR). Drug-polymer solubility and interaction parameters were estimated by Hansen solubility parameters and Hildebrand-Scott equation. The obtained values signified drug-polymer miscibility. The detailed in vitro physicochemical evaluations of the developed filament through HME and its derived 3D printed tablet by FDM technique were assessed thoroughly by several analytical means such as light microscopy, DSC, XRD, FT-IR, SEM, etc. The average disintegration time of this developed 3D printed IR tablet was found to be 63.33 (±3.6) sec complying with the USP limit. Additionally, in vitro dissolution study data revealed almost close correlations and both showed 100% of drug release within 15 min, thus complying with the definition of IR tablet. Thus, this study demonstrates the feasibility of directly using olanzapine-Kollicoat^® IR through the HME process without the addition of any plasticizers, organic solvents, etc. and coupling of HME with 3D printing technology allowing prototypes of IR tablet of olanzapine.

Pandemic-Driven Development of a Medical-Grade, Economic and Decentralized Applicable Polyolefin Filament for Additive Fused Filament Fabrication

A polyolefin with certified biocompatibility according to USP class VI was used by our group as feedstock for filament-based 3D printing to meet the highest medical standards in order to print personal protective equipment for our university hospital during the ongoing pandemic. Besides the chemical resistance and durability, as well as the ability to withstand steam sterilization, this polypropylene (PP) copolymer is characterized by its high purity, as achieved by highly efficient and selective catalytic polymerization. As the PP copolymer is suited to be printed with all common printers in fused filament fabrication (FFF), it offers an eco-friendly cost–benefit ratio, even for large-scale production. In addition, a digital workflow was established focusing on common desktop FFF printers in the medical sector. It comprises the simulation-based optimization of personalized print objects, considering the inherent material properties such as warping tendency, through to validation of the process chain by 3D scanning, sterilization, and biocompatibility analysis of the printed part. This combination of digital data processing and 3D printing with a sustainable and medically certified material showed great promise in establishing decentralized additive manufacturing in everyday hospital life to meet peaks in demand, supply bottlenecks, and enhanced personalized patient treatment.