3D-printed microfluidic chip for the preparation of glycyrrhetinic acid-loaded ethanolic liposomes

Injectable Hydrogel With Glycyrrhizic Acid and Asiaticoside-Loaded Liposomes for Wound Healing

BACKGROUND

Open skin wounds increase the risk of infections and can compromise health. Therefore, applying medications to promote healing at the injury site is crucial. In practice, direct drug delivery is often difficult to maintain for a long time due to rapid absorption or wiping off, which reduces the efficiency of wound healing. Consequently, the development of bioactive materials with both antibacterial and wound-healing properties is highly desirable.

METHODS

This study synthesized liposomes loaded with glycyrrhizic acid (GA) and asiaticoside (AS) by film dispersion-ultrasonication method, which were then incorporated into a GelMA solution and cross-linked by ultraviolet light to form a bioactive composite hydrogel for wound dressings.

RESULTS

This hydrogel is conducive to the transport of nutrients and gas exchange. Compared with GelMA hydrogel (swelling rate 69.8% ± 5.7%), the swelling rate of GelMA/Lip@GA@AS is lower, at 52.1% ± 1.0%. GelMA/Lip@GA@AS also has better compression and rheological properties, and the in vitro biodegradability is not significantly different from that of the collagenase-treated group. In addition, the hydrogel polymer has a stable drug release rate, good biocompatibility, and an angiogenic promoting effect. In vitro experiments prove that, at concentrations of 0.5, 1, 2, and 3 mg/mL, GelMA/Lip@GA@AS can inhibit the growth of Staphylococcus aureus.

CONCLUSION

We synthesized GelMA/Lip@GA@AS hydrogel and found it possesses advantageous mechanical properties, rheology, and biodegradability. Experimental results in vitro showed that the bioactive hydrogel could efficiently release drugs, exhibit biocompatibility, and enhance angiogenesis and antimicrobial effects. These results suggest the promising application of GelMA/Lip@GA@AS hydrogel in wound-dressing materials.

Leveraging machine learning to streamline the development of liposomal drug delivery systems

Drug delivery systems efficiently and safely administer therapeutic agents to specific body sites. Liposomes, spherical vesicles made of phospholipid bilayers, have become a powerful tool in this field, especially with the rise of microfluidic manufacturing during the COVID-19 pandemic. Despite its efficiency, microfluidic liposomal production poses challenges, often requiring laborious, optimization on a case-by-case basis. This is due to a lack of comprehensive understanding and robust methodologies, compounded by limited data on microfluidic production with varying lipids. Artificial intelligence offers promise in predicting lipid behaviour during microfluidic production, with the still unexploited potential of streamlining development. Herein we employ machine learning to predict critical quality attributes and process parameters for microfluidic-based liposome production. Validated models predict liposome formation, size, and production parameters, significantly advancing our understanding of lipid behaviour. Extensive model analysis enhanced interpretability and investigated underlying mechanisms, supporting the transition to microfluidic production. Unlocking the potential of machine learning in drug development can accelerate pharmaceutical innovation, making drug delivery systems more adaptable and accessible.

18‑α‑glycyrrhetinic acid induces apoptosis in gingival fibroblasts exposed to phenytoin

Phenytoin (PHT)-induced gingival overgrowth is caused by the increased proliferation and reduced apoptosis of gingival fibroblasts in inflammatory gingiva. Licorice has long been used as a component of therapeutic preparations. It inhibits cell proliferation, induces cell apoptosis and has anti-inflammatory effects. 18-α-glycyrrhetinic acid (18α-GA), the active compound in licorice, promotes apoptosis in various types of cells. The present study determined whether 18α-GA affects apoptosis in gingival fibroblasts exposed to PHT. The present study aimed to establish a basis for the therapeutic application of 18α-GA to treat the gingival overgrowth induced by PHT. Human gingival fibroblasts from healthy donors were cultured to semi-confluence and then stimulated in serum-free DMEM containing PHT with or without 18α-GA for subsequent experiments. Apoptotic cells were detected by ELISA. Analysis of the distribution of cell cycle phases and the apoptotic cell population was performed by flow cytometry. The expression levels of mRNAs and proteins of apoptotic regulators were measured using reverse transcription-quantitative PCR and western blotting, respectively. Caspase (CASP) activities were assessed by an ELISA. Treatment with 18α-GA markedly increased the number of apoptotic cells, reduced BCL2 mRNA expression, increased CASP2 and receptor (TNFRSF)-interacting serine-threonine kinase 1 (RIPK1) domain containing adaptor with death domain, Fas (TNFRSF6)-associated via death domain, RIPK1, tumor necrosis factor receptor superfamily; member 1A, TNF receptor-associated factor 2, CASP2, CASP3 and CASP9 mRNA expression, and also upregulated the protein expression levels and activities of caspase-2, caspase-3 and caspase-9. These results demonstrated that 18α-GA induced apoptosis through the activation of the Fas and TNF pathways in the death receptor signaling pathway in gingival fibroblasts treated with PHT. 18α-GA exhibited therapeutic potential for the treatment of PHT-induced gingival overgrowth.

3D-Printed MEMS in Italy

MEMS devices are more and more commonly used as sensors, actuators, and microfluidic devices in different fields like electronics, opto-electronics, and biomedical engineering. Traditional fabrication technologies cannot meet the growing demand for device miniaturisation and fabrication time reduction, especially when customised devices are required. That is why additive manufacturing technologies are increasingly applied to MEMS. In this review, attention is focused on the Italian scenario in regard to 3D-printed MEMS, studying the techniques and materials used for their fabrication. To this aim, research has been conducted as follows: first, the commonly applied 3D-printing technologies for MEMS manufacturing have been illustrated, then some examples of 3D-printed MEMS have been reported. After that, the typical materials for these technologies have been presented, and finally, some examples of their application in MEMS fabrication have been described. In conclusion, the application of 3D-printing techniques, instead of traditional processes, is a growing trend in Italy, where some exciting and promising results have already been obtained, due to these new selected technologies and the new materials involved.

Transformative applications of additive manufacturing in biomedical engineering: bioprinting to surgical innovations

This paper delves into the diverse applications and transformative impact of additive manufacturing (AM) in biomedical engineering. A detailed analysis of various AM technologies showcases their distinct capabilities and specific applications within the medical field. Special emphasis is placed on bioprinting of organs and tissues, a revolutionary area where AM has the potential to revolutionize organ transplantation and regenerative medicine by fabricating functional tissues and organs. The review further explores the customization of implants and prosthetics, demonstrating how tailored medical devices enhance patient comfort and performance. Additionally, the utility of AM in surgical planning is examined, highlighting how printed models contribute to increased surgical precision, reduced operating times, and minimized complications. The discussion extends to the 3D printing of surgical instruments, showcasing how these bespoke tools can improve surgical outcomes. Moreover, the integration of AM in drug delivery systems, including the development of innovative drug-loaded implants, underscores its potential to enhance therapeutic efficacy and reduce side effects. It also addresses personalized prosthetic implants, regulatory frameworks, biocompatibility concerns, and the future potential of AM in global health and sustainable practices.

Liposome-Hydrogel Composites for Controlled Drug Delivery Applications

Various controlled delivery systems (CDSs) have been developed to overcome the shortcomings of traditional drug formulations (tablets, capsules, syrups, ointments, etc.). Among innovative CDSs, hydrogels and liposomes have shown great promise for clinical applications thanks to their cost-effectiveness, well-known chemistry and synthetic feasibility, biodegradability, biocompatibility and responsiveness to external stimuli. To date, several liposomal- and hydrogel-based products have been approved to treat cancer, as well as fungal and viral infections, hence the integration of liposomes into hydrogels has attracted increasing attention because of the benefit from both of them into a single platform, resulting in a multifunctional drug formulation, which is essential to develop efficient CDSs. This short review aims to present an updated report on the advancements of liposome-hydrogel systems for drug delivery purposes.

Recent developments in the fabrication of food microparticles and nanoparticles using microfluidic systems

Microfluidics is revolutionizing the production of microparticles and nanoparticles, offering precise control over dimensions and internal structure. This technology facilitates the creation of colloidal delivery systems capable of encapsulating and releasing nutraceuticals. Nutraceuticals, often derived from food-grade ingredients, can be used for developing functional foods. This review focuses on the principles and applications of microfluidic systems in crafting colloidal delivery systems for nutraceuticals. It explores the foundational principles behind the development of microfluidic devices for nutraceutical encapsulation and delivery. Additionally, it examines the prospects and challenges with using microfluidics for functional food development. Microfluidic systems can be employed to form emulsions, liposomes, microgels and microspheres, by manipulating minute volumes of fluids flowing within microchannels. This versatility can enhance the dispersibility, stability, and bioavailability of nutraceuticals. However, challenges as scaling up production, fabrication complexity, and microchannel clogging hinder the widespread application of microfluidic technologies. In conclusion, this review highlights the potential role of microfluidics in design and fabrication of nutraceutical delivery systems. At present, this technology is most suitable for exploring the role of specific delivery system features (such as particle size, composition and morphology) on the stability and bioavailability of nutraceuticals, rather than for large-scale production of nutraceutical delivery systems.

Microfluidic synthesis of lipid-based nanoparticles for drug delivery: recent advances and opportunities

Microfluidic technologies are revolutionizing the synthesis of nanoscale lipid particles and enabling new opportunities for the production of lipid-based nanomedicines. By harnessing the benefits of microfluidics for controlling diffusive and advective transport within microfabricated flow cells, microfluidic platforms enable unique capabilities for lipid nanoparticle synthesis with precise and tunable control over nanoparticle properties. Here we present an assessment of the current state of microfluidic technologies for lipid-based nanoparticle and nanomedicine production. Microfluidic techniques are discussed in the context of conventional production methods, with an emphasis on the capabilities of microfluidic systems for controlling nanoparticle size and size distribution. Challenges and opportunities associated with the scaling of manufacturing throughput are discussed, together with an overview of emerging microfluidic methods for lipid nanomedicine post-processing. The impact of additive manufacturing on current and future microfluidic platforms is also considered.

Microfluidics-mediated Liposomal Nanoparticles for Cancer Therapy: Recent Developments on Advanced Devices and Technologies

Liposomes, spherical particles with phospholipid double layers, have been extensively studied over the years as a means of drug administration. Conventional manufacturing techniques like thin-film hydration and extrusion have limitations in controlling liposome size and distribution. Microfluidics enables superior tuning of parameters during the self-assembly of liposomes, producing uniform populations. This review summarizes microfluidic methods for engineering liposomes, including hydrodynamic flow focusing, jetting, micro mixing, and double emulsions. The precise control over size and lamellarity afforded by microfluidics has advantages for cancer therapy. Liposomes created through microfluidics and designed to encapsulate chemotherapy drugs have exhibited several advantageous properties in cancer treatment. They showcase enhanced permeability and retention effects, allowing them to accumulate specifically in tumor tissues passively. This passive targeting of tumors results in improved drug delivery and efficacy while reducing systemic toxicity. Promising results have been observed in pancreatic, lung, breast, and ovarian cancer models, making them a potential breakthrough in cancer therapy. Surface-modified liposomes, like antibodies or carbohydrates, also achieve active targeting. Overall, microfluidic fabrication improves reproducibility and scalability compared to traditional methods while maintaining drug loading and biological efficacy. Microfluidics-engineered liposomal formulations hold significant potential to overcome challenges in nanomedicine-based cancer treatment.

Microfluidic manufacturing of tioconazole loaded keratin nanocarriers: Development and optimization by design of experiments

Fungal infections of the skin, nails, and hair are a common health concern affecting a significant proportion of the population worldwide. The current treatment options include topical and systematic agents which have low permeability and prolonged treatment period, respectively. Consequently, there is a growing need for a permeable, effective, and safe treatment. Keratin nanoparticles are a promising nanoformulation that can improve antifungal agent penetration, providing sustainable targeted drug delivery. In this study, keratin nanoparticles were prepared using a custom-made 3D-printed microfluidic chip and the manufacturing process was optimized using the design of experiments (DoE) approach. The total flow rate (TFR), flow rate ratio (FRR), and keratin concentration were found to be the most influential factors of the size and polydispersity index (PDI) of the nanoparticles. The crosslinking procedure by means of tannic acid as safe and biocompatible compound was also optimized. Keratin nanoparticles loaded with a different amount of tioconazole showed a size lower than 200 nm, a PDI lower than 0.2 and an encapsulation efficiency of 91 ± 1.9 %. Due to their sustained drug release, the formulations showed acceptable in vitro biocompatibility. Furthermore, a significant inhibitory effect compared to the free drug against Microsporum canis.

Enhancing antioxidant delivery through 3D printing: a pathway to advanced therapeutic strategies

The rapid advancement of 3D printing has transformed industries, including medicine and pharmaceuticals. Integrating antioxidants into 3D-printed structures offers promising therapeutic strategies for enhanced antioxidant delivery. This review explores the synergistic relationship between 3D printing and antioxidants, focusing on the design and fabrication of antioxidant-loaded constructs. Incorporating antioxidants into 3D-printed matrices enables controlled release and localized delivery, improving efficacy while minimizing side effects. Customization of physical and chemical properties allows tailoring of antioxidant release kinetics, distribution, and degradation profiles. Encapsulation techniques such as direct mixing, coating, and encapsulation are discussed. Material selection, printing parameters, and post-processing methods significantly influence antioxidant release kinetics and stability. Applications include wound healing, tissue regeneration, drug delivery, and personalized medicine. This comprehensive review aims to provide insights into 3D printing-assisted antioxidant delivery systems, facilitating advancements in medicine and improved patient outcomes for oxidative stress-related disorders.

Digital light processing 3D printing for microfluidic chips with enhanced resolution via dosing- and zoning-controlled vat photopolymerization

Conventional manufacturing techniques to fabricate microfluidic chips, such as soft lithography and hot embossing process, have limitations that include difficulty in preparing multiple-layered structures, cost- and labor-consuming fabrication process, and low productivity. Digital light processing (DLP) technology has recently emerged as a cost-efficient microfabrication approach for the 3D printing of microfluidic chips; however, the fabrication resolution for microchannels is still limited to sub-100 microns at best. Here, we developed an innovative DLP printing strategy for high resolution and scalable microchannel fabrication by dosing- and zoning-controlled vat photopolymerization (DZC-VPP). Specifically, we proposed a modified mathematical model to precisely predict the accumulated UV irradiance for resin photopolymerization, thereby providing guidance for the fabrication of microchannels with enhanced resolution. By fine-tuning the printing parameters, including optical irradiance, exposure time, projection region, and step distance, we can precisely tailor the penetration irradiance stemming from the photopolymerization of the neighboring resin layers, thereby preventing channel blockage due to UV overexposure or compromised bonding stability owing to insufficient resin curing. Remarkably, this strategy can allow the preparation of microchannels with cross-sectional dimensions of 20 μm × 20 μm using a commercial printer with a pixel size of 10 μm × 10 μm; this is significantly higher resolution than previous reports. In addition, this method can enable the scalable and biocompatible fabrication of microfluidic drop-maker units that can be used for cell encapsulation. In general, the current DZC-VPP method can enable major advances in precise and scalable microchannel fabrication and represents a significant step forward for widespread applications of microfluidics-based techniques in biomedical fields.

3D Printing Technologies in Personalized Medicine, Nanomedicines, and Biopharmaceuticals

3D printing technologies enable medicine customization adapted to patients' needs. There are several 3D printing techniques available, but majority of dosage forms and medical devices are printed using nozzle-based extrusion, laser-writing systems, and powder binder jetting. 3D printing has been demonstrated for a broad range of applications in development and targeting solid, semi-solid, and locally applied or implanted medicines. 3D-printed solid dosage forms allow the combination of one or more drugs within the same solid dosage form to improve patient compliance, facilitate deglutition, tailor the release profile, or fabricate new medicines for which no dosage form is available. Sustained-release 3D-printed implants, stents, and medical devices have been used mainly for joint replacement therapies, medical prostheses, and cardiovascular applications. Locally applied medicines, such as wound dressing, microneedles, and medicated contact lenses, have also been manufactured using 3D printing techniques. The challenge is to select the 3D printing technique most suitable for each application and the type of pharmaceutical ink that should be developed that possesses the required physicochemical and biological performance. The integration of biopharmaceuticals and nanotechnology-based drugs along with 3D printing ("nanoprinting") brings printed personalized nanomedicines within the most innovative perspectives for the coming years. Continuous manufacturing through the use of 3D-printed microfluidic chips facilitates their translation into clinical practice.

Optimisation of liquorice extract microencapsulation and bioaccessibility of its bioactives

In this work, functional liquorice powder beverage (FLPB) with standardised glycyrrhizin (GL), glycyrrhetinic acid (GA), carbenoxolone (CBX), and liquiritin (LQ) contents, was produced by encapsulating Glycyrrhiza glabra extract with maltodextrin (MD) by spray drying. Encapsulation parameters of the FLPB were optimised as MD:GL 3.4:1, inlet temperature: 149 °C, and air flow: 8.9 L min−1. GL, GA, LQ, CBX, and yield in powdered beverage produced using these optimised parameters were 6.8 g L−1, 81.1 mg L−1, 24.7 mg L−1, 0.79 g L−1, and 30.95%, respectively. Moreover, the effect of the encapsulation on the bioaccessibility of GL, GA, CBX, and LQ bioactives in G. glabra was evaluated. According to the obtained results, FLPB exhibited a higher bioaccessibility index for GL, GA, CBX, and LQ compared to the aqueous extract.

Integrated network pharmacology and experimental analysis unveil multi-targeted effect of 18α- glycyrrhetinic acid against non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is one of the most malignant types of cancer with soaring incidence rates worldwide, attributed to its heterogeneity and complex etiology. Evidently, alternative anti-cancer therapies comprising traditional medicines and natural products have gained attention for their ability to act as chemopreventive agents with minimal toxicities, either alone or in combination. Accumulating studies have substantiated the inevitability of network pharmacology studies for effectively mapping molecular targets of natural products against multifaceted diseases, including cancer. The 18α-Glycyrrhetinic acid (18α-GA), a triterpenoid found in licorice plants, has shown promising medicinal properties, although, its mechanism of action against NSCLC yet remains elusive. The present study was conducted to explore the anti- NSCLC potential of 18α-GA, employing integrative network pharmacology, molecular docking, and experimental research. Initially, network analysis revealed 181 common targets of 18α-GA in NSCLC as shown in the “compound-target- disease” network employing Cytoscape 3.8.2. Further analyses identified EGFR, AKT1, PI3KR1, MAPK1, IGF1, and SRC as the most crucial hub targets of 18α-GA against NSCLC. Moreover, molecular docking simulations and functional enrichment analyses indicated the involvement of multiple signaling pathways in suppressing NSCLC. Subsequent in-vitro studies verified the antiproliferative effect of 18α-GA on two NSCLC cancer cell lines, H1299 and A549. Mechanistically, 18α-GA arrested cell cycle at the G1 phase, induced apoptosis, decreased migratory potential, and protein expression levels of EGFR-PI3K/AKT, as examined by flow cytometry, morphological assessment, RT-PCR, and western blot. In conclusion, this study delineates the therapeutic potential and underlying mechanism(s) of 18α-GA as a putative novel drug against NSCLC. However, further studies are warranted to elucidate the complete molecular mechanism(s) using animal models of NSCLC.

A 3D Printer in the Lab: Not Only a Toy

Although 3D printers are becoming more common in households, they are still under-represented in many laboratories worldwide and regarded as toys rather than as laboratory equipment. This short review wants to change this conservative point of view. This mini-review focuses on fused deposition modeling printers and what happens after acquiring your first 3D printer. In short, these printers melt plastic filament and deposit it layer by layer to create the final object. They are getting cheaper and easier to use, and nowadays it is not difficult to find good 3D printers for less than €500. At such a price, a 3D printer is one, if not the most, versatile piece of equipment you can have in a laboratory.

Log P Determines Licorice Flavonoids Release Behaviors and Classification from CARBOMER Cross-Linked Hydrogel

The dynamic drug release mechanisms from Carbomer 940 (CP) hydrogels have not been systematically explored elsewhere. This study aimed to investigate the quantitative structure−activity relationship of licorice flavonoids (LFs) compounds on their drug release from CP hydrogels based on LFs-CP interactions and drug solubility in the release medium. Ten LFs-CP hydrogels were formulated, and their in vitro release study was conducted. The intermolecular forces of LFs-CP systems were characterized by FTIR, molecular docking and molecular dynamic simulation. Ten LFs compounds were classified into I (high-release capability) LFs and II (low-release capability) LFs according to the different negative correlations between drug release percent at 48 h and intermolecular forces of drugs-CP, respectively. Moreover, high-release LFs possessed significantly lower log P and higher drug solubility in the release medium than low-release LFs. All I LFs release behaviors best followed the first-order equation, while II LFs release characteristics best fitted the zero-order equation except for isoliquiritigenin. Log P mainly affect the hydrogel relaxation process for I drugs release and the drug diffusion process for II drugs release. Higher log P values for LFs resulted in higher intermolecular strength for I drugs-CP systems and lower drug solubility in the release medium for II drugs, which hindered drug release. Hydrophobic association forces in drug-CP hydrogel played a more and more dominant role in hindering I LFs release with increasing release time. On the other hand, lower drug solubility in the release medium restricted II LFs release, and the dominant role of drug solubility in the release medium increased in 24 h followed by a significant decline after 36 h. Collectively, log P of LFs served as a bridge to determine LFs compound release behaviors and classification from CP hydrogels, which provided guidelines for reasonable design of LFs hydrogels in pharmaceutical topical formulations.

Synthesis and Biological Characterization of the New Glycolipid Lactose Undecylenate (URB1418)

As a follow-up to our previous studies on glycolipid surfactants, a new molecule, that is lactose 6′-O-undecylenate (URB1418), was investigated. To this end, a practical synthesis and studies aimed at exploring its specific properties were carried out. URB1418 showed antifungal activities against Trichophyton rubrum F2 and Candida albicans ATCC 10231 (MIC 512 μg/mL) and no significant antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. At the same time, it presented anti-inflammatory properties, as documented by the dose-dependent reduction in LPS-induced NO release in RAW 264.7 cells, while a low antioxidant capacity in the range of concentrations tested (EC50 > 200 µM) was also observed. Moreover, URB1418 offers the advantage of being more stable than the reference polyunsaturated lactose esters and of being synthesized using a “green” procedure, involving an enzymatic method, high yield and low manufacturing cost. For all these reasons and the absence of toxicity (HaCaT cells), the new glycolipid presented herein could be considered an interesting compound for applications in various fields.

Microfluidic-Assisted Preparation of Targeted pH-Responsive Polymeric Micelles Improves Gemcitabine Effectiveness in PDAC: In Vitro Insights

Simple Summary

This research suggests a new potential therapeutic approach to pancreatic ductal adenocarcinoma to improve drug effectiveness and overcome drug resistance. A double actively targeted gemcitabine delivery system, consisting of polymeric micelles, was developed by microfluidic technique to ensure a narrow size distribution, a good colloidal stability, and drug-encapsulation efficiency for the selective and controlled release of the loaded drug, in response to the pH variations and uPAR expression in tumors. In vitro studies assessed that the release of the drug in the acidic environment was higher than in the neutral one, and that the pH-responsive and uPAR-targeted polymeric micelles enhanced the antitumor properties of gemcitabine in models resembling the pancreatic tumor microenvironment.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) represents a great challenge to the successful delivery of the anticancer drugs. The intrinsic characteristics of the PDAC microenvironment and drugs resistance make it suitable for therapeutic approaches with stimulus-responsive drug delivery systems (DDSs), such as pH, within the tumor microenvironment (TME). Moreover, the high expression of uPAR in PDAC can be exploited for a drug receptor-mediated active targeting strategy. Here, a pH-responsive and uPAR-targeted Gemcitabine (Gem) DDS, consisting of polymeric micelles (Gem@TpHResMic), was formulated by microfluidic technique to obtain a preparation characterized by a narrow size distribution, good colloidal stability, and high drug-encapsulation efficiency (EE%). The Gem@TpHResMic was able to perform a controlled Gem release in an acidic environment and to selectively target uPAR-expressing tumor cells. The Gem@TpHResMic displayed relevant cellular internalization and greater antitumor properties than free Gem in 2D and 3D models of pancreatic cancer, by generating massive damage to DNA, in terms of H2AX phosphorylation and apoptosis induction. Further investigation into the physiological model of PDAC, obtained by a co-culture of tumor spheroids and cancer-associated fibroblast (CAF), highlighted that the micellar system enhanced the antitumor potential of Gem, and was demonstrated to overcome the TME-dependent drug resistance. In vivo investigation is warranted to consider this new DDS as a new approach to overcome drug resistance in PDAC.

Engineering 3D Printed Microfluidic Chips for the Fabrication of Nanomedicines

Currently, there is an unmet need to manufacture nanomedicines in a continuous and controlled manner. Three-dimensional (3D) printed microfluidic chips are an alternative to conventional PDMS chips as they can be easily designed and manufactured to allow for customized designs that are able to reproducibly manufacture nanomedicines at an affordable cost. The manufacturing of microfluidic chips using existing 3D printing technologies remains very challenging because of the intricate geometry of the channels. Here, we demonstrate the manufacture and characterization of nifedipine (NFD) polymeric nanoparticles based on Eudragit L-100 using 3D printed microfluidic chips with 1 mm diameter channels produced with two 3D printing techniques that are widely available, stereolithography (SLA) and fuse deposition modeling (FDM). Fabricated polymeric nanoparticles showed good encapsulation efficiencies and particle sizes in the range of 50-100 nm. SLA chips possessed better channel resolution and smoother channel surfaces, leading to smaller particle sizes similar to those obtained by conventional manufacturing methods based on solvent evaporation, while SLA manufactured nanoparticles showed a minimal burst effect in acid media compared to nanoparticles fabricated with FDM chips. Three-dimensional printed microfluidic chips are a novel and easily amenable cost-effective strategy to allow for customization of the design process for continuous manufacture of nanomedicines under controlled conditions, enabling easy scale-up and reducing nanomedicine development times, while maintaining high-quality standards.

3D Printed Integrated Multi-Layer Microfluidic Chips for Ultra-High Volumetric Throughput Nanoliposome Preparation

Although microfluidic approaches for liposomes preparation have been developed, fabricating microfluidic devices remains expensive and time-consuming. Also, owing to the traditional layout of microchannels, the volumetric throughput of microfluidics has been greatly limited. Herein an ultra-high volumetric throughput nanoliposome preparation method using 3D printed microfluidic chips is presented. A high-resolution projection micro stereolithography (PμSL) 3D printer is applied to produce microfluidic chips with critical dimensions of 400 µm. The microchannels of the microfluidic chip adopt a three-layer layout, achieving the total flow rate (TFR) up to 474 ml min⁻¹, which is remarkably higher than those in the reported literature. The liposome size can be as small as 80 nm. The state of flows in microchannels and the effect of turbulence on liposome formation are explored. The experimental results demonstrate that the 3D printed integrated microfluidic chip enables ultra-high volumetric throughput nanoliposome preparation and can control size efficiently, which has great potential in targeting drug delivery systems.

Calorimetric Evaluation of Glycyrrhetic Acid (GA)- and Stearyl Glycyrrhetinate (SG)-Loaded Solid Lipid Nanoparticle Interactions with a Model Biomembrane

Glycyrrhetic acid (GA) and stearyl glycyrrhetinate (SG) are two interesting compounds from Glycyrrhiza glabra, showing numerous biological properties widely applied in the pharmaceutical and cosmetic fields. Despite these appreciable benefits, their potential therapeutic properties are strongly compromised due to unfavourable physical-chemical features. The strategy exploited in the present work was to develop solid lipid nanoparticles (SLNs) as carrier systems for GA and SG delivery. Both formulations loaded with GA and SG (GA-SLNs and SG-SLNs, respectively) were prepared by the high shear homogenization coupled to ultrasound (HSH-US) method, and we obtained good technological parameters. DSC was used to evaluate their thermotropic behaviour and ability to act as carriers for GA and SG. The study was conducted by means of a biomembrane model (multilamellar vesicles; MLVs) that simulated the interaction of the carriers with the cellular membrane. Unloaded and loaded SLNs were incubated with the biomembranes, and their interactions were evaluated over time through variations in their calorimetric curves. The results of these studies indicated that GA and SG interact differently with MLVs and SLNs; the interactions of SG-SLNs and GA-SLNs with the biomembrane model showed different variations of the MLVs calorimetric curve and suggest the potential use of SLNs as delivery systems for GA.

Galenic Lab-on-a-Chip concept for lipid nanocapsules production

The continuous production of drug delivery systems assisted by microfluidics has drawn a growing interest because of the high reproducibility, low batch-to-batch variations, narrow and controlled particle size distributions and scale-up ease induced by this kind of processes. Besides, microfluidics offers opportunities for high throughput screening of process parameters and the implementation of process characterization techniques as close to the product as possible. In this context, we propose to spotlight the GALECHIP concept through the development of an instrumented microfluidic pilot considered as a Galenic Lab-on-a-Chip to formulate nanomedicines, such as lipid nanocapsules (LNCs), under controlled process conditions. In this paper we suggest an optimal rational development in terms of chip costs and designs. First, by using two common additive manufacturing techniques, namely fused deposition modelling and multi-jet modelling to prototype customized 3D microfluidic devices (chips and connectors). Secondly, by manufacturing transparent Silicon (Si)/Glass chips with similar channel geometries but obtained by a new approach of deep reactive ion etching (DRIE) technology suitable with in situ small angle X-ray scattering characterizations. LNCs were successfully produced by a phase inversion composition (PIC) process with highly monodispersed sizes from 25 nm to 100 nm and formulated using chips manufactured by 3D printing and DRIE technologies. The transparent Si/Glass chip was also used for the small angle X-ray scattering (SAXS) analysis of the LNC formulation with the PIC process. The 3D printing and DRIE technologies and their respective advantages are discussed in terms of cost, easiness to deploy and process developments in a GALECHIP point of view.

Biopolymer-liposome hybrid systems for controlled delivery of bioactive compounds: Recent advances

Conventional liposomes still face many challenges associated with the poor physical and chemical stability, considerable loss of encapsulated cargo, lack of stimulus responsiveness, and rapid elimination from blood circulation. Integration of versatile functional biopolymers has emerged as an attractive strategy to overcome the limitation of usage of liposomes. This review comprehensively summarizes the most recent studies (2015-2020) and their challenges aiming at the exploration of biopolymer-liposome hybrid systems, including surface-modified liposomes, biopolymer-incorporated liposomes, guest-in-cyclodextrin-in-liposome, liposome-in-hydrogel, liposome-in-film, and liposome-in-nanofiber. The physicochemical principles and key technical information underlying the combined strategies for the fabrication of polymeric liposomes, the advantages and limitations of each of the systems, and the stabilization mechanisms are discussed through various case studies. Special emphasis is directed toward the synergistic efficiencies of biopolymers and phospholipid bilayers on encapsulation, protection, and controlled delivery of bioactives (e.g., vitamins, carotenoids, phenolics, peptides, and other health-related compounds) for the biomedical, pharmaceutical, cosmetic, and functional food applications. The major challenges, opportunities, and possible further developments for future studies are also highlighted.

Thiolated polymer nanocarrier reinforced with glycyrrhetinic acid for targeted delivery of 5-fluorouracil in hepatocellular carcinoma

The present work investigates the targeting efficacy of a novel thiolated polymer-based nanocomposite reinforced with glycyrrhetinic acid (GA) and loaded with 5-fluorouracil in hepatocellular carcinoma (HCC). The thiolated polymers were synthesized by EDAC-mediated conjugation reactions and lyophilization. The nanoparticles were prepared by solvent diffusion and high-pressure homogenization method. The prepared nanocomposite was characterized by Fourier transform infrared (FTIR) radiation, x-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Pharmacological evaluation of the formulation was carried out on a rat model of diethylnitrosamine (DEN), and carbon tetrachloride (CCl₄)-induced HCC and MTT assay was carried out with HEP-G2 cell line. In silico studies were conducted to investigate the probable mechanistic pathway of the nanocomposite. FTIR and XRD analysis indicated the successful thiolation of the polymers and confirmed the formation of the nanocomposite without any incompatibilities. DLS, SEM/EDX and AFM characterization confirmed that the nanoparticles were within the nano-size range. MTT assay implied the cytotoxic nature of the nanocomposite against hepatic carcinoma cells. The in vivo study revealed that serum SGOT, SGPT, ALP, GGT and total bilirubin levels were significantly reduced, in comparison with disease control and the result was confirmed by histopathology studies. The results of the HPLC analysis of liver homogenate confirmed the liver targeting ability of the nanocomposite. In silico studies exhibited significant binding affinity of GA and thiolated Eudragit towards liver homolog receptor-1 (LRH-1) suggesting that the developed nanocomposite could be a potential material for the treatment of HCC.

Printing-Based Assay and Therapy of Antioxidants

Antioxidants are essential in regulating various physiological functions and oxidative deterioration. Over the past decades, many researchers have paid attention to antioxidants and studied the screening of antioxidants from natural products and their utilization for treatments in diverse pathological conditions. Nowadays, as printing technology progresses, its influence in the field of biomedicine is growing significantly. The printing technology has many advantages. Especially, the capability of designing sophisticated platforms is useful to detect antioxidants in various samples. The high flexibility of 3D printing technology is advantageous to create geometries for customized patient treatment. Recently, there has been increasing use of antioxidant materials for this purpose. This review provides a comprehensive overview of recent advances in printing technology-based assays to detect antioxidants and 3D printing-based antioxidant therapy in the field of tissue engineering. This review is divided into two sections. The first section highlights colorimetric assays using the inkjet-printing methods and electrochemical assays using screen-printing techniques for the determination of antioxidants. Alternative screen-printing techniques, such as xurography, roller-pen writing, stamp contact printing, and laser-scribing, are described. The second section summarizes the recent literature that reports antioxidant-based therapy using 3D printing in skin therapeutics, tissue mimetic 3D cultures, and bone tissue engineering.