Redispersible 3D printed nanomedicines: An original application of the semisolid extrusion technique

Application of 3D printing on the design and development of pharmaceutical oral dosage forms

3D printing technologies confer an unparalleled degree of control over the material distribution on the structures they produce, which has led them to become an extremely attractive research topic in pharmaceutical dosage form development, especially for the design of personalized treatments. With fine tuning in material selection and careful design, these technologies allow to tailor not only the amount of drug administered but the biopharmaceutical behaviour of the dosage forms as well. While fused deposition modelling (FDM) is still the most studied 3D printing technology in this area, others are gaining more relevance, which has led to many new and exciting dosage forms developed during 2022 and 2023. Considering that these technologies, in time, will join the current manufacturing methods and with the ever-increasing knowledge on this topic, our review aims to explore the advantages and limitations of 3D printing technologies employed in the design and development of pharmaceutical oral dosage forms, giving special focus to the most important aspects governing the resulting drug release profiles.

3D printed dispersible efavirenz tablets: A strategy for nasogastric administration in children

Enteral feeding tubes (EFTs) can be placed in children diagnosed with HIV which need nutritional support due to malnutrition. EFTs are the main route for medication administration in these patients, bringing up concerns about off label use of medicines, dose inaccuracy and tube clogging. Here we report for the first time the use of selective laser sintering (SLS) 3D printing to develop efavirenz (EFZ) dispersible printlets for patients with HIV that require EFT administration. Water soluble polymers Parteck® MXP and Kollidon® VA64 were used to obtain both 500 mg (P500 and K500) and 1000 mg printlets (P1000 and K1000) containing 200 mg of EFZ each. The use of SLS 3D printing obtained porous dosage forms with high drug content (20 % and 40 % w/w) and drug amorphization using both polymers. P500, K500 and K1000 printlets reached disintegration in under 230 s in 20 mL of water (25 ± 1 °C), whilst P1000 only partially disintegrated, possibly due to saturation of the polymer in the medium. As a result, the development of dispersible EFZ printlets using hydrophilic polymers can be explored as a potential strategy for drug delivery through EFTs in paediatrics with HIV, paving the way towards the exploration of more rapidly disintegrating polymers and excipients for SLS 3D printing.

Rheological insights into 3D printing of drug products: Drug nanocrystal-poloxamer gels for semisolid extrusion

The importance of ink rheology to the outcome of 3D printing is well recognized. However, rheological properties of printing inks containing drug nanocrystals have not been widely investigated. Therefore, the objective of this study was to establish a correlation between the composition of nanocrystal printing ink, the ink rheology, and the entire printing process. Indomethacin was used as a model poorly soluble drug to produce nanosuspensions with improved solubility properties through particle size reduction. The nanosuspensions were further developed into semisolid extrusion 3D printing inks with varying nanocrystal and poloxamer 407 concentrations. Nanocrystals were found to affect the rheological properties of the printing inks both by being less self-supporting and having higher yielding resistances. During printing, nozzle blockages occurred. Nevertheless, all inks were found to be printable. Finally, the rheological properties of the inks were successfully correlated with various printing and product properties. Overall, these experiments shed new light on the rheological properties of printing inks containing nanocrystals.

Pimobendan controlled release guar gum printlets: Tailoring drug doses for personalised veterinary medicines

Treating chronic heart diseases in dogs is challenging due to variations in mass within and between species. Pimobendan (PBD), a veterinary drug only, is prescribed in specific cases of chronic heart disease in dogs and is available on the market in only a few different doses. Furthermore, the therapy itself is challenging due to the large size of the chewable tablets and the requirement for twice-daily administration. The development of customised and on-demand PBD medicines by three-dimensional (3D) printing has been proposed to circumvent these disadvantages. In this study, we designed controlled-release flavoured printlets containing PBD. We evaluated the use of two natural polymers, guar or xanthan gums, as the main component of the printing inks. Guar gum showed the better rheological behavior and printability by semisolid extrusion. The printlets were produced in three different shapes and sizes to allow dose customisation. Guar gum printlets showed a PBD controlled release profile, regardless of their shape or size. Therefore, we have demonstrated a novel approach for controlling PBD drug release and tailoring the dose by employing a natural polymer to produce 3D-printed tablets. This study represents a significant step towards the development of 3D-printed guar gum controlled-release formulations for veterinary applications.

Potential Applications and Additive Manufacturing Technology-Based Considerations of Mesoporous Silica: A Review

Nanoporous materials are categorized as microporous (pore sizes 0.2-2 nm), mesoporous (pore sizes 2-50 nm), and macroporous (pore sizes 50-1000 nm). Mesoporous silica (MS) has gained a significant interest due to its notable characteristics, including organized pore networks, specific surface areas, and the ability to be integrated in a variety of morphologies. Recently, MS has been widely accepted by range of manufacturer and as drug carrier. Moreover, silica nanoparticles containing mesopores, also known as mesoporous silica nanoparticles (MSNs), have attracted widespread attention in additive manufacturing (AM). AM commonly known as three-dimensional printing is the formalized rapid prototyping (RP) technology. AM techniques, in comparison to conventional methods, aid in reducing the necessity for tooling and allow versatility in product and design customization. There are generally several types of AM processes reported including VAT polymerization (VP), powder bed fusion (PBF), sheet lamination (SL), material extrusion (ME), binder jetting (BJ), direct energy deposition (DED), and material jetting (MJ). Furthermore, AM techniques are utilized in fabrication of various classified fields such as architectural modeling, fuel cell manufacturing, lightweight machines, medical, and fabrication of drug delivery systems. The review concisely elaborates on applications of mesoporous silica as versatile material in fabrication of various AM-based pharmaceutical products with an elaboration on various AM techniques to reduce the knowledge gap.

3D Printing Technology as a Promising Tool to Design Nanomedicine-Based Solid Dosage Forms: Contemporary Research and Future Scope

3D printing technology in medicine is gaining great attention from researchers since the FDA approved the first 3D-printed tablet (Spritam®) on the market. This technique permits the fabrication of various types of dosage forms with different geometries and designs. Its feasibility in the design of different types of pharmaceutical dosage forms is very promising for making quick prototypes because it is flexible and does not require expensive equipment or molds. However, the development of multi-functional drug delivery systems, specifically as solid dosage forms loaded with nanopharmaceuticals, has received attention in recent years, although it is challenging for formulators to convert them into a successful solid dosage form. The combination of nanotechnology with the 3D printing technique in the field of medicine has provided a platform to overcome the challenges associated with the fabrication of nanomedicine-based solid dosage forms. Therefore, the major focus of the present manuscript is to review the recent research developments that involved the formulation design of nanomedicine-based solid dosage forms utilizing 3D printing technology. Utilization of 3D printing techniques in the field of nanopharmaceuticals achieved the successful transformation of liquid polymeric nanocapsules and liquid self-nanoemulsifying drug delivery systems (SNEDDS) to solid dosage forms such as tablets and suppositories easily with customized doses as per the needs of the individual patient (personalized medicine). Furthermore, the present review also highlights the utility of extrusion-based 3D printing techniques (Pressure-Assisted Microsyringe-PAM; Fused Deposition Modeling-FDM) to produce tablets and suppositories containing polymeric nanocapsule systems and SNEDDS for oral and rectal administration. The manuscript critically analyzes contemporary research related to the impact of various process parameters on the performance of 3D-printed solid dosage forms.

Combinational System of Lipid-Based Nanocarriers and Biodegradable Polymers for Wound Healing: An Updated Review

Skin wounds have imposed serious socioeconomic burdens on healthcare providers and patients. There are just more than 25,000 burn injury-related deaths reported each year. Conventional treatments do not often allow the re-establishment of the function of affected regions and structures, resulting in dehydration and wound infections. Many nanocarriers, such as lipid-based systems or biobased and biodegradable polymers and their associated platforms, are favorable in wound healing due to their ability to promote cell adhesion and migration, thus improving wound healing and reducing scarring. Hence, many researchers have focused on developing new wound dressings based on such compounds with desirable effects. However, when applied in wound healing, some problems occur, such as the high cost of public health, novel treatments emphasizing reduced healthcare costs, and increasing quality of treatment outcomes. The integrated hybrid systems of lipid-based nanocarriers (LNCs) and polymer-based systems can be promising as the solution for the above problems in the wound healing process. Furthermore, novel drug delivery systems showed more effective release of therapeutic agents, suitable mimicking of the physiological environment, and improvement in the function of the single system. This review highlights recent advances in lipid-based systems and the role of lipid-based carriers and biodegradable polymers in wound healing.

3D Printing Technologies in Personalized Medicine, Nanomedicines, and Biopharmaceuticals

3D printing technologies enable medicine customization adapted to patients' needs. There are several 3D printing techniques available, but majority of dosage forms and medical devices are printed using nozzle-based extrusion, laser-writing systems, and powder binder jetting. 3D printing has been demonstrated for a broad range of applications in development and targeting solid, semi-solid, and locally applied or implanted medicines. 3D-printed solid dosage forms allow the combination of one or more drugs within the same solid dosage form to improve patient compliance, facilitate deglutition, tailor the release profile, or fabricate new medicines for which no dosage form is available. Sustained-release 3D-printed implants, stents, and medical devices have been used mainly for joint replacement therapies, medical prostheses, and cardiovascular applications. Locally applied medicines, such as wound dressing, microneedles, and medicated contact lenses, have also been manufactured using 3D printing techniques. The challenge is to select the 3D printing technique most suitable for each application and the type of pharmaceutical ink that should be developed that possesses the required physicochemical and biological performance. The integration of biopharmaceuticals and nanotechnology-based drugs along with 3D printing ("nanoprinting") brings printed personalized nanomedicines within the most innovative perspectives for the coming years. Continuous manufacturing through the use of 3D-printed microfluidic chips facilitates their translation into clinical practice.

3D printing of pharmaceuticals for disease treatment

Three-dimensional (3D) printing or Additive manufacturing has paved the way for developing and manufacturing pharmaceuticals in a personalized manner for patients with high volume and rare diseases. The traditional pharmaceutical manufacturing process involves the utilization of various excipients to facilitate the stages of blending, mixing, pressing, releasing, and packaging. In some cases, these excipients cause serious side effects to the patients. The 3D printing of pharmaceutical manufacturing avoids the need for excessive excipients. The two major components of a 3D printed tablet or dosage form are polymer matrix and drug component alone. Hence the usage of the 3D printed dosage forms for disease treatment will avoid unwanted side effects and provide higher therapeutic efficacy. With respect to the benefits of the 3D printed pharmaceuticals, the present review was constructed by discussing the role of 3D printing in producing formulations of various dosage forms such as fast and slow releasing, buccal delivery, and localized delivery. The dosage forms are polymeric tablets, nanoparticles, scaffolds, and films employed for treating different diseases.

Bioadhesive 3D-Printed Skin Drug Delivery Polymeric Films: From the Drug Loading in Mesoporous Silica to the Manufacturing Process

The alliance between 3D printing and nanomaterials brings versatile properties to pharmaceuticals, but few studies have explored this approach in the development of skin delivery formulations. In this study, clobetasol propionate (CP) was loaded (about 25% w/w) in mesoporous silica nanomaterial (MSN) to formulate novel bioadhesive and hydrophilic skin delivery films composed of pectin (5% w/v) and carboxymethylcellulose (5% w/v) by 3D printing. As a hydrophobic model drug, CP was encapsulated in MSN at a 3:1 (w/w) ratio, resulting in a decrease of CP crystallinity and an increase of its dissolution efficiency after 72 h (65.70 ± 6.52%) as compared to CP dispersion (40.79 ± 4.75%), explained by its partial change to an amorphous form. The CP-loaded MSN was incorporated in an innovative hydrophilic 3D-printable ink composed of carboxymethylcellulose and pectin (1:1, w/w), which showed high tensile strength (3.613 ± 0.38 N, a homogenous drug dose (0.48 ± 0.032 mg/g per film) and complete CP release after 10 h. Moreover, the presence of pectin in the ink increased the skin adhesion of the films (work of adhesion of 782 ± 105 mN·mm). Therefore, the alliance between MSN and the novel printable ink composed of carboxymethylcellulose and pectin represents a new platform for the production of 3D-printed bioadhesive films, opening a new era in the development of skin delivery systems.