Investigating the Use of Magnetic Nanoparticles As Alternative Sintering Agents in Selective Laser Sintering (SLS) 3D Printing of Oral Tablets

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.

A Novel 3D Printing Particulate Manufacturing Technology for Encapsulation of Protein Therapeutics: Sprayed Multi Adsorbed-Droplet Reposing Technology (SMART)

Recently, various innovative technologies have been developed for the enhanced delivery of biologics as attractive formulation targets including polymeric micro and nanoparticles. Combined with personalized medicine, this area can offer a great opportunity for the improvement of therapeutics efficiency and the treatment outcome. Herein, a novel manufacturing method has been introduced to produce protein-loaded chitosan particles with controlled size. This method is based on an additive manufacturing technology that allows for the designing and production of personalized particulate based therapeutic formulations with a precise control over the shape, size, and potentially the geometry. Sprayed multi adsorbed-droplet reposing technology (SMART) consists of the high-pressure extrusion of an ink with a well determined composition using a pneumatic 3D bioprinting approach and flash freezing the extrudate at the printing bed, optionally followed by freeze drying. In the present study, we attempted to manufacture trypsin-loaded chitosan particles using SMART. The ink and products were thoroughly characterized by dynamic light scattering, rheometer, Scanning Electron Microscopy (SEM), and Fourier Transform Infra-Red (FTIR) and Circular Dichroism (CD) spectroscopy. These characterizations confirmed the shape morphology as well as the protein integrity over the process. Further, the effect of various factors on the production were investigated. Our results showed that the concentration of the carrier, chitosan, and the lyoprotectant concentration as well as the extrusion pressure have a significant effect on the particle size. According to CD spectra, SMART ensured Trypsin's secondary structure remained intact regardless of the ink composition and pressure. However, our study revealed that the presence of 5% (w/v) lyoprotectant is essential to maintain the trypsin's proteolytic activity. This study demonstrates, for the first time, the viability of SMART as a single-step efficient process to produce biologics-based stable formulations with a precise control over the particulate morphology which can further be expanded across numerous therapeutic modalities including vaccines and cell/gene therapies.

Dual Photothermal/Chemotherapy of Melanoma Cells with Albumin Nanoparticles Carrying Indocyanine Green and Doxorubicin Leads to Immunogenic Cell Death

Recent focus on cancer immunotherapies has led to significant interest in the development of therapeutic strategies that can lead to immunogenic cell death (ICD), which can cause activation of an immune response against tumor cells and improve immunotherapy outcomes by enhancing the immunogenicity of the tumor microenvironment. In this work, a nanomedicine-mediated combination therapy is used to deliver the ICD inducers doxorubicin (Dox), a chemotherapeutic agent, and indocyanine green (ICG), a photothermal agent. These agents are loaded into nanoparticles (NPs) of bovine serum albumin (BSA) that are prepared through a desolvation process. The formulation of BSA NPs is optimized to achieve NPs of 102.6  nm in size and loadings of 8.55 % and 5.69 % (w/w) for ICG and Dox, respectively. The controlled release of these agents from the BSA NPs is confirmed. Upon laser irradiation for 2.5 min, NPs at a dose of 62.5 μg mL^-1 are able to increase the temperature of the cells by 7 °C and thereby inhibit the growth of B16F10 melanoma cells in vitro. Surface presentation of heat shock proteins and calreticulin from the cells after treatment confirmed the ability of the Dox/ICG loaded BSA NPs to induce ICD in the melanoma cells.

Emerging 3D printing technologies for drug delivery devices: Current status and future perspective

The 'one-size-fits-all' approach followed by conventional drug delivery platforms often restricts its application in pharmaceutical industry, due to the incapability of adapting to individual pharmacokinetic traits. Driven by the development of additive manufacturing (AM) technology, three-dimensional (3D) printed drug delivery medical devices have gained increasing popularity, which offers key advantages over traditional drug delivery systems. The major benefits include the ability to fabricate 3D structures with customizable design and intricate architecture, and most importantly, ease of personalized medication. Furthermore, the emergence of multi-material printing and four-dimensional (4D) printing integrates the benefits of multiple functional materials, and thus provide widespread opportunities for the advancement of personalized drug delivery devices. Despite the remarkable progress made by AM techniques, concerns related to regulatory issues, scalability and cost-effectiveness remain major hurdles. Herein, we provide an overview on the latest accomplishments in 3D printed drug delivery devices as well as major challenges and future perspectives for AM enabled dosage forms and drug delivery systems.

Induction of immunogenic cell death of cancer cells through nanoparticle-mediated dual chemotherapy and photothermal therapy

The use of nanomedicines to induce immunogenic cell death is a new strategy that aims to increase tumor immunogenicity and thereby prime tumors for further immunotherapies. In this study, we developed a nanoparticle formulation for combinatory chemotherapy and photothermal therapy based only on materials previously used in FDA-approved products and investigated the effect of the combinatory therapy on the growth inhibition and induction of immunogenic cell death in human MDA-MB-231 breast cancer cells. The formulation consists of ~108-nm nanoparticles made of poly(lactic acid)-b-methoxy poly(ethylene glycol) which carry doxorubicin for chemotherapy and indocyanine green for photothermal therapy. A 0.3 mg/mL suspension of NPs increased the medium temperature up to 10 °C upon irradiation with an 808-nm diode laser. In vitro studies showed that combination of laser assisted indocyanine green-mediated photothermal therapy and doxorubicin-mediated chemotherapy effectively eradicated cancer cells and resulted in the highest level of damage-associated molecular pattern presentation (calreticulin, high mobility group box 1, and adenosine triphosphate) compared to the individual treatments alone. These results demonstrate that our nanoparticle-mediated combinatory approach led to the most intense immunogenic cell death when compared to individual chemotherapy or photothermal therapy, making it a potent option for future in vivo studies in combination with cancer immunotherapies.

High Throughput Preparation of Poly(Lactic-Co-Glycolic Acid) Nanoparticles Using Fiber Fluidic Reactor

Polymeric nanoparticles (NPs) have a variety of biomedical, biotechnology, agricultural and environmental applications. As such, a great need has risen for the fabrication of these NPs in large scales. In this study, we used a high throughput fiber reactor for the preparation of poly(lactic-co-glycolic acid) (PLGA) NPs via nanoprecipitation. The fiber reactor provided a high surface area for the controlled interaction of an organic phase containing the PLGA solution with an aqueous phase, containing poly(vinyl alcohol) (PVA) as a stabilizer. This interaction led to the self-assembly of the polymer into the form of NPs. We studied operational parameters to identify the factors that have the greatest influence on the properties of the resulting PLGA NPs. We found that the concentration of the PLGA solution is the factor that has the greatest effect on NP size, polydispersity index (PDI), and production rate. Increasing PLGA concentration increased NP sizes significantly, while at the same time decreasing the PDI value. The second factor that was found to affect NP properties was the concentration of PVA solution, which resulted in increased NP sizes and decreased production rates. Flowrates of the feed streams also affected NP size to a lesser extent, while changing the operational temperature did not change the product's features. In general, the results demonstrate that fiber reactors are a suitable method for the large-scale, continuous preparation of polymeric NPs suitable for biomedical applications.

Ligand-modified Biopolymeric Nanoparticles as Efficient Tools for Targeted Cancer Therapy

Non-specific distribution of chemotherapeutic agents in the body where they affect both cancer as well as normal cells resulting in serious side effects is the major reason for the high mortality rate of cancer. Thus, there is a need for developing targeted delivery strategies specially employing nanoplatform-based cancer therapies that provide specific targeting to tumor cells. In this regard, biopolymeric nanoplatforms such as liposomes, protein- and polysaccharide- based nanoparticles have gained more attention due to their biocompatibility, biodegradability and less toxicity. In terms of targeting, monoclonal antibodies (mAbs), folic acid (FA) and transferrin (Tf) can be considered as the moieties to be attached to the nanoplatforms to deliver their payload to its site of action. This review article focuses on the recent progress in the field of targeted drug and gene delivery systems with emphasizes on liposomes, protein (specially human and bovine serum albumin)-based nanoparticles and polysaccharide (specially chitosan and dextran)-based nanoparticles as the biopolymeric nanoplatforms, which are decorated with mAbs, FA and Tf as the targeting ligands.