Top-Down and Bottom-Up Approaches in 3D Printing Technologies for Drug Delivery Challenges

Abstract

3-Dimensional printing (3DP) constitutes a raft of technologies, based on different physical mechanisms, that generate a 3-dimensional physical object from a digital model. Because of its rapid fabrication and precise geometry, 3DP has gained a prominent focus in biomedical and nanobiomaterials research. Despite advancements in targeted, controlled, and pulsatile drug delivery, the achievement of site-specific and disease-responsive drug release and stringent control over in vivo biodistribution, are still some of the important, challenging areas for pharmaceutical research and development and existing drug delivery techniques. Microelectronic industries are capable of generating nano-/microdrug delivery devices at high throughputs with a highly precise control over design. Successful miniaturizations of micro-pumps with multireservoir architectures for delivery of pharmaceuticals developed by micro-electromechanical systems technology were more acceptable than implantable devices. Inkjet printing technologies, which dispense a precise amount of polymer ink solutions, find applications in controlled drug delivery. Bioelectronic products have revolutionized drug delivery technologies. Designing nanoparticles by nanoimprint lithography showed a controlled drug release pattern, biodistribution, and in vivo transport. This review highlights the "top-down" and "bottom-up" approaches of the most promising 3DP technologies and their broader applications in biomedical and therapeutic drug delivery, with critical assessment of its merits, demerits, and intellectual property rights challenges.

3D Printing in Pharmaceutical Sector: An Overview

“…Multiple dosage forms like implants, zero-order release tablets etc. that include polymer as a part of their formulation can be made by this method [9,[19][20][21]. [8]).…”

“…It is a powder-based 3D printing that utilizes powder as a substrate on which layer by layer different combinations of active ingredients and ink is sprayed which is of varying droplet size that eventually solidifies into solid dosage form [9,19,[24][25][26][27][28].…”

“…By eradicating the use of unnecessary resources, manufacturing cost can also be reduced. For instance, 20-mg tablets could be potentially formulated as 1-mg tablets as per need [19]. 4.…”

Biomedical Applications from a Direct Digital Manufacturing Perspective

“…The use of this technique enables pharmaceutical companies to obtain uniformly dispensed droplets in the picoliter range useful for drug delivery/dose personalisation systems with high placement accuracy [14]. By changing the droplet size and the 1ratio of active pharmaceutical ingredient and polymeric substrate, DoD printing allows drug dosage suitable to the patient's need and layering of multiple drugs [4].…”

“…By changing the droplet size and the 1ratio of active pharmaceutical ingredient and polymeric substrate, DoD printing allows drug dosage suitable to the patient's need and layering of multiple drugs [4]. Such procedure enables site-specific and disease responsive drug release and also a stringent control over in vivo biodistribution of the drug [14]. Newest application of DDM to medicine has gained attention from several cancer therapy research groups where recreation of tumour microenvironments for cancer related studies has been discussed.…”