Search

Interest in 3D printing has been growing rapidly especially in pharmaceutical industry due to its multiple advantages such as manufacturing versatility, personalization of medicine, scalability, and cost effectiveness. Inkjet based 3D printing gained special attention after FDA's approval of Spritam® manufactured by Aprecia pharmaceuticals in 2015. The precision and printing efficiency of 3D printing is strongly influenced by the dynamics of ink/binder jetting, which further depends on the ink's fluid properties. In this study, Computational Fluid Dynamics (CFD) has been utilized to study the drop formation process during inkjet-based 3D printing for piezoelectric and thermal printhead geometries using Volume of Fluid (VOF) method. To develop the CFD model commercial software ANSYS-Fluent was used. The developed CFD model was experimentally validated using drop watcher setup to record drop progression and drop velocity. During the study, water, Fujifilm model fluid, and Amitriptyline drug solutions were evaluated as the ink solutions. The drop properties such as drop volume, drop diameter, and drop velocity were examined in detail in response to change ink solution properties such as surface tension, viscosity, and density. A good agreement was observed between the experimental and simulation data for drop properties such as drop volume and drop velocity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The drug loading efficiency was evaluated using a binder-jet 3D printing process by incorporating an active pharmaceutical ingredient (API) in ink, and quantifying the printability property of ink solutions. A dimensionless parameter Ohnesorge was calculated to understand the printability property of the ink solutions. A pre-formulation study was also carried out for the raw materials and printed tablets using thermal analysis and compendial tests. The compendial characterization of the printed tablets was evaluated with respect to weight variation, hardness, disintegration, and size; Amitriptyline Hydrochloride was considered as the model API in this study. Four concentrations of the API ink solutions (5, 10, 20, 40 mg/mL) were used to print four printed tablet batches using the same tablet design file. The excipient mixture used in the study was kept the same and consists of Lactose monohydrate, Polyvinyl pyrrolidone K30, and Di-Calcium phosphate Anhydrate. The minimum drug loading achieved was 30 μg with a minimal variation (RSD) of <0.26%. The distribution of the API on the tablet surface and throughout the printed tablets were observed using SEM-EDS. In contrast, the micro-CT images of the printed tablets indicated the porous surface structure of the tablets. The immediate release properties of the printed tablets were determined using a dissolution study in a modified USP apparatus II., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The β-CD encapsulation of two tricyclic antidepressants (TCAs), nortriptyline (NRT) HCl and amitriptyline (AMT) HCl (most widely used TCA), has been thoroughly investigated by single-crystal X-ray diffraction and DFT calculation for insights into the inclusion complexation. X-ray analysis reveals that both drugs insert the A-ring moiety vertically from the β-CD O2H/O3H-side and are kept in position by C5H⋯π interactions, yielding thermodynamically favorable complexes. In the β-CD cavity, NRT and AMT are less open as their butterfly angles are ~10° smaller than those in free HCl salt forms and in complex with proteins. The effect of HCl salt on both complexes is evaluated by DFT full-geometry optimization. When Cl - is directly linked with the NRT NH 2 Me + group, the inclusion complex formed gains stability by 3.65 kcal mol -1 through N5'H⋯Cl⋯HO26 H-bond chain, compared to the complex of NRT base. The addition of HCl to N5' of the side chain marginally affects the structures of β-CD-TCA complexes. This study provides a rigorous crystallographic evidence for the β-CD-TCA complexation and a theoretical view on the improved stability of TCA in the CD cavity, supporting the pharmacological benefit of CD encapsulation in reducing the TCA side effects., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)