Publications

Electrospinning has become a widely used and efficient method for manufacturing nanofibers from diverse polymers. This study introduces an advanced electrospinning technique, Xspin - a multi-functional 3D printing platform coupled with electrospinning system, integrating a customised 3D printhead, MaGIC - Multi-channeled and Guided Inner Controlling printheads. The Xspin system represents a cutting-edge fusion of electrospinning and 3D printing technologies within the realm of pharmaceutical sciences and biomaterials. This innovative platform excels in the production of novel fiber with various materials and allows for the creation of highly customized fiber structures, a capability hitherto unattainable through conventional electrospinning methodologies. By integrating the benefits of electrospinning with the precision of 3D printing, the Xspin system offers enhanced control over the scaffold morphology and drug release kinetics. Herein, we fabricated a model floating pharmaceutical dosage for the dual delivery of curcumin and ritonavir and thoroughly characterized the product. Fourier transform infrared (FTIR) spectroscopy demonstrated that curcumin chemically reacted with the polymer during the Xspin process. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) confirmed the solid-state properties of the active pharmaceutical ingredient after Xspin processing. Scanning electron microscopy (SEM) revealed the surface morphology of the Xspin-produced fibers, confirming the presence of the bifiber structure. To optimize the quality and diameter control of the electrospun fibers, a design of experiment (DoE) approach based on quality by design (QbD) principles was utilized. The bifibers expanded to approximately 10-11 times their original size after freeze-drying and effectively entrapped 87% curcumin and 84% ritonavir. In vitro release studies demonstrated that the Xspin system released 35% more ritonavir than traditional pharmaceutical pills in 2 h, with curcumin showing complete release in pH 1.2 in 5 min, simulating stomach media. Furthermore, the absorption rate of curcumin was controlled by the characteristics of the linked polymer, which enables both drugs to be absorbed at the desired time. Additionally, multivariate statistical analyses (ANOVA, pareto chart, etc.) were conducted to gain better insights and understanding of the results such as discern statistical differences among the studied groups. Overall, the Xspin system shows significant potential for manufacturing nanofiber pharmaceutical dosages with precise drug release capabilities, offering new opportunities for controlled drug delivery applications.

Production of amorphous solid dispersions (ASDs) is an effective strategy to promote the solubility and bioavailability of poorly water soluble medicinal substances. In general, ASD is manufactured using a variety of classic and modern techniques, most of which rely on either melting or solvent evaporation. This proof-of-concept study is the first ever to introduce electromagnetic drop-on-demand (DoD) technique as an alternative solvent evaporation-based method for producing ASDs. Herein 3D printing of ASDs for three drug-polymer combinations (efavirenz-Eudragit L100-55, lumefantrine-hydroxypropyl methylcellulose acetate succinate, and favipiravir-polyacrylic acid) was investigated to ascertain the reliability of this technique. Polarized light microscopy, differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and Fourier Transform  Infrared (FTIR) spectroscopy results supported the formation of ASDs for the three drugs by means of DoD 3D printing, which significantly increases the equilibrium solubility of efavirenz from 0.03 ± 0.04 µg/ml to 21.18 ± 4.20 µg/ml, and the equilibrium solubility of lumefantrine from 1.26 ± 1.60 µg/ml to 20.21 ± 6.91 µg/ml. Overall, the reported findings show how this new electromagnetic DoD technology can have a potential to become a cutting-edge 3D printing solvent-evaporation technique for on-demand and continuous manufacturing of ASDs for a variety of drugs.

This study aimed to develop and optimize formulations containinga BCS Class IV drug by improving its solubility and permeability. Herein development of self-emulsifying solid lipid matrices was investigated as carrier systems for a BCS Class IV model drug. Self-emulsifying drug delivery systems (SEDDS) have been extensively investigated for formulating drugs with poor water solubility. However, manufacturing SEDDS is challenging. These systems usually have low drug-loading capacities, and the incorporated drugs tend to recrystallize during storage, which severely impacts the storage stability in vitro and performance in vivo. Moreover, they require greater amounts (>80%) of lipid carriers, cosolvents, surfactants, and other excipients to keep them from recrystallizing. This in turn is again challenging for high-dose drugs as it affects the size of the final drug product (tablets and capsules). Also, the final liquid nature of the formulation affects the handling and processability of the formulation, which poses challenges during the manufacturing and packaging steps. In this work, we have studied the feasibility of a single-step extrusion process to formulate and optimize solid self-emulsifying granules with a relatively higher drug loading of Ritonavir (RTV), a BCS Class IV drug. Further, we have compared the performance of using these granules as the feedstock for direct powder extrusion-based 3D printing as opposed to the use of physical blends. The stability and solubility-permeability advantage of these granules was also evaluated where SEDDS showed about 27 and 20 fold increase in apparent solublity and permeability compared to bulk drug, respectively. Combining the capabilities of HME to form drug-loaded homogeneous granules as a continuous process along with application of direct printing extruiosn (DPE) 3D printing improves the drug delivery prospects for such candidates.

The application of 3D printing technology in the delivery of macromolecules, such as proteins and enzymes, is limited by the lack of suitable inks. In this study, we report the development of novel inks for 3D printing of constructs containing proteins while maintaining the activity of the proteins during and after printing. Different ink formulations containing Pluronic F-127 (20-35 %, w/v), trehalose (2-10 %, w/v) or mannitol, poly (ethylene glycol) diacrylate (PEGDA) (0 or 10 %, w/w), and diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO, 0 or 0.2 mg/mL) were prepared for 3D-microextrusion printing. The F2 formulation that contained β-galactosidase (β-gal) as a model enzyme, Pluronic F-127 (30 %), and trehalose (10 %) demonstrated the desired viscosity, printability, and dose flexibility. The shear-thinning property of the F2 formulation enabled the printing of β-gal containing constructs with a good peak force during extrusion. After 3D printing, the enzymatic activity of the β-gal in the constructs was maintained for an extended period, depending on the construct design and storage conditions. For instance, there was a 50 % reduction in β-gal activity in the two-layer constructs, but only a 20 % reduction in the four-layer construct (i.e., 54.5 ± 1.2 % and 82.7 ± 9.9 %, respectively), after 4 days of storage. The β-gal activity in constructs printed from the F2 formulation was maintained for up to 20 days when stored in sealed bags at room temperatures (21 ± 2 °C), but not when stored unsealed in the same conditions (e.g., ∼60 % activity loss within 7 days). The β-gal from constructs printed from F2 started to release within 5 min and reached 100 % after 20 min. With the design flexibility offered by the 3D printing, the β-gal release from the constructs was delayed to 3 h by printing a backing layer of β-gal-free F5 ink on the constructs printed from the F2 ink. Finally, ovalbumin as an alternative protein was also incorporated in similar ink compositions. Ovalbumin exhibited a release profile like that of the β-gal, and the release can also be modified with different shape design and/or ink composition. In conclusion, ink formulations that possess desirable properties for 3D printing of protein-containing constructs while maintaining the protein activity during and after printing were developed.

The messenger ribose nucleic acid (mRNA) in the form of Corona virus of 2019 (COVID-19) vaccines were effectively delivered through lipid nanoparticles (LNP) proving its use as effective carriers in clinical applications. In the present work, mRNA (erythropoietin (EPO)) encapsulated LNPs were prepared using a next generation state-of-the-art patented, Sprayed Multi Absorbed-droplet Reposing Technology (SMART) coupled with Multi-channeled and Guided Inner-Controlling printheads (MaGIC) technologies. The LNP-mRNA were synthesized at different N/P ratios and the particles were characterized for particle size and zeta potential (Zetasizer), encapsulation or complexation (gel retardation assay) and transfection (Fluorescence microscopy and ELISA) in MG63 sarcoma cells in vitro. The results showed a narrow distribution of mRNA-lipid particles of 200 nm when fabricated with SMART alone and then the size was reduced to approximately 50 nm with the combination of SMART-MaGIC technologies. The gel retardation assay showed that the N/P > 1 exhibited strong encapsulation of mRNA with lipid. The in vitro results showed the toxicity profile of the lipids where N/P ratio of 5 was optimized with > 50% cell viability. It can be concluded that the functional LNP-mRNA prepared and analyzed with SMART-MaGIC technologies, could be a potential new fabrication method of mRNA loaded LNPs for point-of-service or distributed manufacturing.

3D printing has emerged as a powerful tool demonstrating effectiveness in early screening and targeted delivery for various types of tumors. Although the applications of additive manufacturing for cancer are widespread, the issues of scaling up, quality control and specificity remain. This review presents a comprehensive analysis of the current landscape of use of additive manufacturing in cancer diagnostics and treatment. Furthermore, it proceeds to elucidate the prominent current and future applications of 4D- and 5D-printed micro-swimmers in cancer treatment with particular emphasis on the significant progress made in magnetic, biological and light-based propulsion microrobots. Lastly, the current limitations and future research directions are enumerated. In summary, this paper serves as a comprehensive exploration of the remarkable contributions of additive manufacturing to the diagnosis and treatment of cancer.

The aim of this study was to develop a composite thermosensitive hydrogel for bone regeneration applications. This hydrogel consisted of chitosan, alginate and hydroxyapatite, and was loaded with zoledronic acid as a model drug. The feasibility of three-dimensional (3D) printing of the thermosensitive hydrogel using the extrusion based technique was investigated. The 3D printing technique called Freeform Reversible Embedded Suspended Hydrogel (FRESH) printing was employed for this purpose. To characterize the composite hydrogels, several tests were conducted. The gelation time, rheological properties, and in vitro drug release were analyzed. Additionally, the cell viability test on human osteosarcoma MG-63 cells for the composite hydrogel was assessed using an MTT assay. The results of the study showed that the zoledronic acid-loaded composite thermosensitive hydrogel was successfully printed using the FRESH 3D printing technique which was not possible otherwise i.e., by using traditional 3D printing techniques. Further examination of the printed constructs using a Scanning Electron Microscope revealed the presence of porous and layered structures. The gelation times of the composite thermosensitive hydrogel was determined to be 10 and 20 min, respectively for scaffolds with and without HA, indicating the successful formation of the gel within a reasonable time to the FRESH technique. The flow behavior of the hydrogel was found to be pseudoplastic, following a non-Newtonian flow pattern with Farrow's constant (N) values of 1.708 and 1.853 for scaffolds with and without hydroxyapatite, respectively. In terms of drug release, scaffolds prepared with and without hydroxyapatite reached nearly 100% of zoledronic acid release in 360 h and 48 h, respectively. The cell viability test on human osteosarcoma MG-63 cells using MTT assay has shown increased cell viability % in the case of composite hydrogel, indicating biocompatibility of the scaffold. Overall, this study successfully developed a composite thermosensitive hydrogel loaded with zoledronic acid for bone regeneration applications and was 3D printed using the FRESH 3D printing technique. The results of this study provide valuable insights into the potential use of this composite hydrogel for future biomedical applications.

Four-dimensional (4D) printing, as a newly evolving technology to formulate drug delivery devices, displays distinctive advantages that can autonomously monitor drug release according to the actual physiological circumstances. In this work, we reported our earlier synthesized novel thermo-responsive self-folding feedstock for possible SSE-mediated 3D printing to form a 4D printed construct deploying machine learning (ML) modeling to determine its shape recovery behavior followed by its potential drug delivery applications. Therefore, in the present study, we converted our earlier synthesized temperature-responsive self-folding (both placebo and drug-loaded) feedstock into 4D printed constructs using SSE-mediated 3D printing technology. Further, the shape memory programming of the printed 4D construct was achieved at 50 °C followed by shape fixation at 4 °C. The shape recovery was achieved at 37 °C, and the obtained data were used to train and ML algorithms for batch optimization. The optimized batch showed a shape recovery ratio of 97.41. Further, the optimized batch was used for the drug delivery application using paracetamol (PCM) as a model drug. The % entrapment efficiency of the PCM-loaded 4D construct was found to be 98.11 ± 1.5%. In addition, the in vitro release of PCM from this programmed 4D printed construct confirms temperature-responsive shrinkage/swelling properties via releasing almost 100% ± 4.19 of PCM within 4.0 h. at gastric pH medium. In summary, the proposed 4D printing strategy pioneers the paradigm that can independently control drug release with respect to the actual physiological environment.

Selective laser sintering (SLS) is a single-step, three-dimensional printing (3DP) process that is gaining momentum in the manufacturing of pharmaceutical dosage forms. It also offers opportunities for manufacturing various pharmaceutical dosage forms with a wide array of drug delivery systems. This research aimed to introduce carbonyl iron as a multifunctional magnetic and heat conductive ingredient for the fabrication of oral tablets containing isoniazid, a model antitubercular drug, via SLS 3DP process. Furthermore, the effects of magnetic iron particles on the drug release from the SLS printed tablets under a specially designed magnetic field was studied. Optimization of tablet quality was performed by adjusting SLS printing parameters. The independent factors studied were laser scanning speed, hatching space, and surface/chamber temperature. The responses measured were printed tablets' weight, hardness, disintegration time, and dissolution performance. It has been observed that, for the drug formulation with carbonyl iron, due to its inherent thermal conductivity, sintering tablets required relatively lower laser energy input to form the tablets of the same quality attributes as the other batches that contained no magnetic particles. Also, printed tablets with carbonyl iron released 25% more drugs under a magnetic field than those without it. It can be claimed that magnetic nanoparticles appear as an alternative conductive material to facilitate the sintering process during SLS 3DP of dosage forms.

Bone regeneration using inorganic nanoparticles is a robust and safe approach. In this paper, copper nanoparticles (Cu NPs) loaded with calcium phosphate scaffolds were studied for their bone regeneration potential in vitro. The pneumatic extrusion method of 3D printing was employed to prepare calcium phosphate cement (CPC) and copper loaded CPC scaffolds with varying wt% of copper nanoparticles. A new aliphatic compound Kollisolv MCT 70 was used to ensure the uniform mixing of copper nanoparticles with CPC matrix. The printed scaffolds were studied for physico-chemical characterization for surface morphology, pore size, wettability, XRD, and FTIR. The copper ion release was studied in phosphate buffer saline at pH 7.4. The in vitro cell culture studies for the scaffolds were performed using human mesenchymal stem cells (hMSCs). The cell proliferation study in CPC-Cu scaffolds showed significant cell growth compared to CPC. The CPC-Cu scaffolds showed improved alkaline phosphatase activity and angiogenic potential compared to CPC. The CPC-Cu scaffolds showed significant concentration dependent antibacterial activity in Staphylococcus aureus. Overall, the CPC scaffolds loaded with 1 wt% Cu NPs showed improved activity compared to other CPC-Cu and CPC scaffolds. The results showed that copper has improved the osteogenic, angiogenic and antibacterial properties of CPC scaffolds, facilitating better bone regeneration in vitro.