In Vitro Profile of Hydrocortisone Release from Three-Dimensionally Printed Paediatric Mini-Tablets.

Three-dimensional (3D) printing is quickly being adopted in pharmaceutics due to the many advantages it offers, including treatment, adaptability, the reduction in waste and the accelerated development of new formulations. In this study, micro-extrusion printing was implemented for the production of modified-release hydrocortisone (HCT) mini-tablets for paediatric patients. For the developed formulations, Gelucire® 44/14 and Precirol® ATO 5 were used as the main inks at three different ratios: 70%/30%, 60%/40% and 50%/50%, respectively. The printing parameters (temperature and pressure) were altered accordingly for each ratio to achieve printability. The printed mini-tablets exhibited excellent printing quality, featuring consistent layer thicknesses and smooth surfaces. Dissolution tests were performed, and the results indicated a successful modified release of HCT from the mini-tablets. In summary, micro-extrusion exhibited favourable processing abilities for powder blends, facilitating quick printing and the fabrication of potential personalized dosages.

Personalised oral dosage forms using an ultra-compact tablet press at the point of care.

Over the last 10 years there is an increasing need for the design of personalised medicines at the point of care (PoC) that meet the specific needs of individual patients. A plethora of technologies has been introduced for making affordable personalised pharmaceutical products, which however, do not address manufacturing and regulatory challenges. Here we introduce a novel ultra-compact tablet press which was used for the design and compression of rosuvastatin-aspirin and amiloride-lysonipril bilayer tablets respectively. By applying precision dosing, it was feasible to manufacture tablets of different dose strengths and control features such as hardness, friability and disintegration times. The compaction of on-demand personalised multidrug pills that meet quality standards could revolutionised the treatment of patients at the point of care.

Exosome-like genistein-loaded nanoparticles developed by thin-film hydration and 3D-printed Tesla microfluidic chip: A comparative study.

Exosomes are naturally derived information carriers that present interest as drug delivery systems. However, their vague cargo and isolation difficulties hinder their use in clinical practice. To overcome these limitations, we developed exosome-like nanoparticles, consisted of the main lipids of exosomes, using two distinct methods: thin-film hydration and 3D-printed microfluidics. Our novel microfluidic device, fabricated through digital light processing printing, demonstrated a favorable architecture to produce exosome-like nanoparticles. We compared these two techniques by analyzing the physicochemical characteristics (size, size distribution, and ζ-potential) of both unloaded and genistein-loaded exosome-like nanoparticles, using dynamic and electrophoretic light scattering. Our findings revealed that the presence of small lipophilic molecules, cholesterol and/or genistein, influenced the characteristics of the final formulations differently based on the development approach. Regardless of the initial differences of the formulations, all exosome-like nanoparticles, whether loaded with genistein or not, exhibited remarkable colloidal stability over time. Furthermore, an encapsulation efficiency of over 87% for genistein was achieved in all cases. Additionally, thermal analysis uncovered the presence of metastable phases within the membranes, which could impact the drug delivery efficiency. In summary, this study provides a comprehensive comparison between conventional and innovative methods for producing complex liposomal nanosystems, exemplified by exosome-like nanoparticles.

3D Printing of Personalised Carvedilol Tablets Using Selective Laser Sintering.

Selective laser sintering (SLS) has drawn attention for the fabrication of three-dimensional oral dosage forms due to the plurality of drug formulations that can be processed. The aim of this work was to employ SLS with a CO2 laser for the manufacturing of carvedilol personalised dosage forms of various strengths. Carvedilol (CVD) and vinylpyrrolidone-vinyl acetate copolymer (Kollidon VA64) blends of various ratios were sintered to produce CVD tablets of 3.125, 6.25, and 12.5 mg. The tuning of the SLS processing laser intensity parameter improved printability and impacted the tablet hardness, friability, CVD dissolution rate, and the total amount of drug released. Physicochemical characterization showed the presence of CVD in the amorphous state. X-ray micro-CT analysis demonstrated that the applied CO2 intensity affected the total tablet porosity, which was reduced with increased laser intensity. The study demonstrated that SLS is a suitable technology for the development of personalised medicines that meet the required specifications and patient needs.

Three-Dimensionally Printed Vaginal Rings: Perceptions of Women and Gynecologists in a Cross-Sectional Survey.

Three-dimensional printing technologies can be implemented for the fabrication of personalized vaginal rings (VRs) as an alternative approach to traditional manufacturing. Although several studies have demonstrated the potential of additive manufacturing, there is a lack of knowledge concerning the opinions of patients and clinicians. This study aimed to investigate the perception of women and gynecologists regarding VRs with personalized shapes. The devices were printed with different designs (traditional, "Y", "M", and flat circle) by Fused Deposition Modeling for a cross-sectional survey with 155 participants. Their anticipated opinion was assessed through a questionnaire after a visual/tactile analysis of the VRs. The findings revealed that most women would feel comfortable using some of the 3D-printed VR designs and demonstrated good acceptability for the traditional and two innovative designs. However, women presented multiple preferences when the actual geometry was assessed, which directly related to their age, previous use of the vaginal route, and perception of comfort. In turn, gynecologists favored prescribing traditional and flat circle designs. Overall, although there was a difference in the perception between women and gynecologists, they had a positive opinion of the 3D-printed VRs. Finally, the personalized VRs could lead to an increase in therapeutic adherence, by meeting women's preferences.

3D Printed Flavor-Rich Chewable Pediatric Tablets Fabricated Using Microextrusion for Point of Care Applications.

Over the past few years, 3D printing technologies have gained interest in the development of medicinal products for personalized use at the point of care. The printing of drug products offers personalization and flexibility in dose, shape/design, and flavor, potentially enhancing acceptability in pediatric populations. In this study, we present the design and development of ibuprofen (IBU) chewable flavor-rich personalized dosage forms by using microextrusion for the processing of powdered blends. The optimization processing parameters such as applied pneumatic pressure and temperature resulted in high quality printable tablets of various designs with a glossy appearance. Physicochemical characterization of the printed dosages revealed that IBU was molecularly dispersed in the methacrylate polymer matrix and the formation of H bonding. A panelist's study demonstrated excellent taste masking and aroma evaluation when using strawberry and orange flavors. Dissolution studies showed very fast IBU dissolution rates of more than 80% within the first 10 min in acidic media. Microextrusion is a 3D printing technology that can be effectively used to generate pediatric patient centric dosage forms at the point of care.

3D printing of LEGO® like designs with tailored release profiles for treatment of sleep disorder.

3D printed LEGO®-like designs are an attractive approach for the development of compartmental delivery systems due to their potential for dose personalisation through the customisation of drug release profiles. Additive manufacturing technologies such as Fused Deposition Modelling (FDM) are ideal for the printing of structures with complex geometries and various sizes. This study is a paradigm for the fabrication of 3D printed LEGO® -like tablets by altering the design of the modular units and the filament composition for the delivery of different drug substances. By using a combination of placebo and drug loaded compartments comprising of immediate release (hydroxypropyl cellulose) and pH dependant polymers (hypromellose acetate succinate) we were able to customise the release kinetics of melatonin and caffeine that can potentially be used for the treatment of sleep disorders. The LEGO® -like compartments were designed to achieve immediate release of melatonin followed by variable lag times and controlled release of caffeine.

In vivo evaluation of nanostructured lipid carrier systems (NLCs) in mice bearing prostate cancer tumours.

Nanostructure lipid carriers (NLCs) were developed for the delivery of curmumin (CRN), a potent anticancer agent with low bioavailability, for the treatment of prostate cancer. NLCs prepared using high pressure homogenization (HPH) with around 150 nm particle size, - 40 V ζ-potential and excellent long-term stability. Cellular uptake of CRN-SLN showed nanoparticle localization in the cytoplasm around the nucleus. CRN-NLCs were assessed using flow cytometry and found to cause early and late apoptotic events at 100 µg/ml CRN concentrations. CRN-NLC nanoparticles were administrated to nude mice with LNCaP prostate cancer xenografts and demonstrated substantial tumour volume suppression (40%) with no weight loss compared to pure CRN (ethanolic solution). Overall, NLCs were proved a suitable carrier for passive drug delivery and cancer treatment.

Evaluation of 3D Printability and Biocompatibility of Microfluidic Resin for Fabrication of Solid Microneedles.

In this study, we have employed Digital Light Processing (DLP) printing technology for the fabrication of solid microneedle (MN) arrays. Several arrays with various geometries, such as cones, three-sided pyramids and four-sided pyramids, with different height to aspect ratios of 1:1, 2:1 and 3:1, were printed. Post-processing curing optimizations showed that optimal mechanical properties of the photocurable resin were obtained at 40 °C and 60 min. Ex vivo skin studies showed that piercing forces, penetration depth and penetration width were affected by the MN geometry and height to aspect ratio. Cone-shaped MNs required lower applied forces to penetrate skin and showed higher penetration depth with increasing height to aspect ratio, followed by three-sided and four-sided printed arrays. Cytotoxicity studies presented 84% cell viability of human fibroblasts after 2.5 h, suggesting the very good biocompatibility of the photocurable resin. Overall, DLP demonstrated excellent printing capacity and high resolution for a variety of MN designs.

Personalised paediatric chewable Ibuprofen tablets fabricated using 3D micro-extrusion printing technology.

Three-dimensional (3D) printing is becoming an attractive technology for the design and development of personalized paediatric dosage forms with improved palatability. In this work micro-extrusion based printing was implemented for the fabrication of chewable paediatric ibuprofen (IBU) tablets by assessing a range of front runner polymers in taste masking. Due to the drug-polymer miscibility and the IBU plasticization effect, micro-extrusion was proved to be an ideal technology for processing the drug/polymer powder blends for the printing of paediatric dosage forms. The printed tablets presented high printing quality with reproducible layer thickness and a smooth surface. Due to the drug-polymer interactions induced during printing processing, IBU was found to form a glass solution confirmed by differential calorimetry (DSC) while H-bonding interactions were identified by confocal Raman mapping. IBU was also found to be uniformly distributed within the polymer matrices at molecular level. The tablet palatability was assessed by panellists and revealed excellent taste masking of the IBU's bitter taste. Overall micro-extrusion demonstrated promising processing capabilities of powder blends for rapid printing and development of personalised dosage forms.

Coupling of Fused Deposition Modeling and Inkjet Printing to Produce Drug Loaded 3D Printed Tablets.

In the current study, we have coupled Fused Deposition Modelling (FDM) for the fabrication of plain polyvinyl alcohol (PVA) tablets followed by dispensing of minoxidil ethanolic solutions using inkjet printing. The use of a drop-on-solid printing approach facilitates an accurate and reproducible process while it controls the deposition of the drug amounts. For the purpose of the study, the effect of the solvent was investigated and minoxidil ink solutions of ethanol 70% v/v (P70) or absolute ethanol (P100) were applied on the plain PVA tablets. Physicochemical characterization showed that solvent miscibility with the polymer substrate plays a key role and can lead to the formation of drug crystals on the surface or drug absorption in the polymer matrix. The produced minoxidil tablets showed sustained release profiles or initial bursts strongly affected by the solvent grade used for dispensing the required dose on drug loaded 3D printed tablets. This paradigm demonstrates that the coupling of FDM and inkjet printing technologies could be used for rapid development of personalized dosage forms.

Development of 3D printed drug-eluting contact lenses.

OBJECTIVES: The aim of the work was to introduce 3D printing technology for the design and fabrication of drug-eluting contact lenses (DECL) for the treatment of glaucoma. The development of 3D printed lenses can effectively overcome drawbacks of existing approaches by using biocompatible medical grade polymers that provide sustained drug release of timolol maleate for extended periods. METHODS: Hot melt extrusion was coupled with fusion deposition modelling (FDM) to produce printable filaments of ethylene-vinyl acetate copolymer-polylactic acid blends at various ratios loaded with timolol maleate. Physicochemical and mechanical characterisation of the printed filaments was used to optimise the printing of the contact lenses. KEY FINDINGS: 3D printed lenses with an aperture (opening) and specified dimensions could be printed using FDM technology. The lenses presented a smooth surface with good printing resolution while providing sustained release of timolol maleate over 3 days. The findings of this study can be used for the development of personalised DECL in the future.

3D printing advances in the development of stents.

3D printing technologies have found several applications within the biomedical sector including in the fabrication of medical devices, advanced visualization, diagnosis planning and simulation of surgical procedures. One of the areas in which of 3D printing is anticipated to revolutionised is the manufacturing of implantable bioresorbable drug-eluting scaffolds (stents). The ability to customize and create personalised tailor-made bioresorbable scaffolds has the potential to help solve many of the challenges associated with stenting, such as inappropriate stent sizing and design, abolish late stent thrombosis and help artery growth; 3D printing offers a rapid prototyping and effective method of producing stents making customization of designs feasible. This review provides an overview of the subjects and summarizes the latest research in the 3D printing technologies employed for the design and fabrication of bioresorbable stents including materials with the required printable and mechanical properties. Finally, we present a regulatory perspective on the development and engineering of 3D printed implantable stents.

Preparation of Solid Dispersions of Simvastatin and Soluplus Using a Single-Step Organic Solvent-Free Supercritical Fluid Process for the Drug Solubility and Dissolution Rate Enhancement.

The study was designed to investigate the feasibility of supercritical carbon dioxide (scCO2) processing for the preparation of simvastatin (SIM) solid dispersions (SDs) in Soluplus® (SOL) at temperatures below polymer's glass transition. The SIM content in the SDs experimental design was kept at 10, 20 and 30% to study the effect of the drug-polymer ratio on the successful preparation of SDs. The SIM-SOL formulations, physical mixtures (PMs) and SDs were evaluated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and dissolution studies. The scCO2 processing conditions and drug-polymer ratio were found to influence the physicochemical properties of the drug in formulated SDs. SIM is a highly crystalline drug; however, physicochemical characterisation carried out by SEM, DSC, and XRD demonstrated the presence of SIM in amorphous nature within the SDs. The SIM-SOL SDs showed enhanced drug dissolution rates, with 100% being released within 45 min. Moreover, the drug dissolution from SDs was faster and higher in comparison to PMs. In conclusion, this study shows that SIM-SOL dispersions can be successfully prepared using a solvent-free supercritical fluid process to enhance dissolution rate of the drug.

Personalised Tasted Masked Chewable 3D Printed Fruit-Chews for Paediatric Patients.

The development of personalised paediatric dosage forms using 3D printing technologies has gained significant interest over the last few years. In the current study extruded filaments of the highly bitter Diphenhydramine Hydrochloride (DPH) were fabricated by using suitable hydrophilic carries such as hydroxypropyl cellulose (Klucel ELFTM) and a non-ionic surfactant (Gelucire 48/16TM) combined with sweetener (Sucralose) and strawberry flavour grades. The thermoplastic filaments were used to print 3D fruit-chew designs by Fused Deposition Modelling (FDM) technology. Physicochemical characterisation confirmed the formation of glass solution where DPH was molecularly dispersed within the hydrophilic carriers. DPH was released rapidly from the 3D printed fruit-chew designs with >85% within the first 30 min. Trained panellists performed a full taste and sensory evaluation of the sweetener intensity and the strawberry aroma. The evaluation showed complete taste masking of the bitter DPH and revealed a synergistic effect of the sweetener and the strawberry flavour with enhanced sweet strawberry, fruity and aftertaste perception. The findings of the study can be used for the development of paediatric dosage forms with enhanced organoleptic properties, palatability and medication adherence.

Investigation on hot melt extrusion and prediction on 3D printability of pharmaceutical grade polymers.

The development of printable filaments has been identified as a critical aspect for the processing of pharmaceutical grade polymers and the fabrication of oral solid dosage forms. In this study a range of plain and drug loaded polymers were investigated and assessed for their printability in comparison to commercial filaments. Physicochemical characterizations of the polymers included differential scanning calorimetry (DSC) thermogravimetric analysis (TGA) and rheology were studied prior to Hot Melt Extrusion processing for the filament fabrication. A texture analyser was used to study the filament mechanical properties in order to derive the maximum tensile strength, Young's Modulus and elongation at break. Principal component analysis was used to compare the printability of the polymer and to identify the contribution of each mechanical property. The analysis showed that maximum tensile strength with a threshold between 15 and 20 MPa is the most critical property for the prediction of the printability. Furthermore, printable filaments were processed using Fusion Deposition Modelling technology and optimal printing parameters were identified. The study demonstrated that the prediction of filament printability is feasible by evaluating the mechanical properties.

Comparative taste-masking evaluation of microencapsulated bitter drugs using Smartseal 30D and ReadyMix for paediatric dosage forms.

The taste of drug substances plays a key role in the development of paediatric formulations with suitable organoleptic properties. The aim of the study was to evaluate the taste masking effectiveness of Smartseal 30D and ReadyMix on a range of bitter drug substances such as diphenhydramine HCl (DPD), ibuprofen lysine (IBU-LS), and phenylephrine HCl (PPH) for the development of paediatric dosage forms. The drugs were microencapsulated in the polymer carriers at 10-20% loadings using spray-drying processing. Spray drying of drug formulations was optimized in terms of percent yield and encapsulation efficiency followed by physicochemical characterization in order to identify the drugs' physical state in the polymer microparticles. The in vivo taste masking efficiency was evaluated using human test panel and showed noticeable reduction of drug's bitterness at all loadings in comparison to the bulk substances.

Advances in Twin-Screw Granulation Processing.

Twin-screw granulation (TSG) is a pharmaceutical process that has gained increased interest from the pharmaceutical industry for its potential for the development of oral dosage forms. The technology has evolved rapidly due to the flexibility of the equipment design, the selection of the process variables and the wide range of processed materials. Most importantly, TSG offers the benefits of both batch and continuous manufacturing for pharmaceutical products, accompanied by excellent process control, high product quality which can be achieved through the implementation of Quality by Design (QbD) approaches and the integration of Process Analytical Tools (PAT). Here, we present basic concepts of the various twin-screw granulation techniques and present in detail their advantages and disadvantages. In addition, we discuss the detail of the instrumentation used for TSG and how the critical processing paraments (CPP) affect the critical quality attributes (CQA) of the produced granules. Finally, we present recent advances in TSG continuous manufacturing including the paradigms of modelling of continuous granulation process, QbD approaches coupled with PAT monitoring for granule optimization and process understanding.