Controlled Drug Delivery Research Articles

Production of Polylactide Nanoparticles Loaded With Isoniazid and Vitamin C: A Promising Candidate for the Treatment of Resistant Forms of Tuberculosis

ABSTRACTNowadays, the method of directed transport of drugs is becoming increasingly important in medicine and pharmacology. It allows for increasing the concentration of delivered substances in a certain place and blocking or severely limiting their accumulation in healthy organs and tissues. One of the promising drug carriers used in the development of controlled drug delivery systems is polylactic acid (PLA). We were interested in using biodegradable polymeric nanoparticles (NPs) loaded with isoniazid (INH) and vitamin C (VC) which have sustained action, targeted delivery, high efficacy, and low toxicity. It will help to expand the use of these simple drugs for the rapid treatment of multidrug‐resistant forms of tuberculosis. Thus, in this work, PLA‐INH‐VC NPs were prepared by double emulsion method where several factors affecting particle size were investigated. TGA/DSC and IR spectroscopy studies identified the presence of molecularly dispersed drugs (INH and VC) in polylactide nanoparticles. VC was found to reduce the degradation of the polymer and thus prolonged the release of the drug from the polymer matrix. PLA‐INH‐VC nanoparticles were analyzed for mycobacterial activity and the nanoparticles were found to inhibit the growth of INH‐resistant mycobacteria.

Synthesis of cefixime loaded PCL/HPMC blend nanoparticles: a controlled release study and in vitro anti-bacterial evaluation

Aim To enhance cefixime’s effectiveness and address drug delivery challenges like concentration at the site, dose, and time, present study investigated the impact of polymer blends on cefixime’s in vitro release profile. Methods Cefixime-loaded nanoparticles were prepared via a modified solvent evaporation method, forming a W/O/W double emulsion. Characterisation included FT-IR, zeta potential, TGA, TEM, and XRD, with in vitro studies and kinetic models used to analyse the release mechanism. Results The PH-4 nanoparticle formulation (80:20 PCL/HPMC, 0.5% PVA) achieved an 81% loading rate, no adverse effects, and a controlled release of 84.66%±2.53 over 30 days. It showed stable physicochemical properties, with in vitro antibacterial tests revealing inhibition zones of 27.4 ± 2.12 mm for E. coli and 17.2 ± 2.23 mm for S. aureus at 12 hours. Conclusion Based on the findings, developed nanoparticulate system containing PCL/HPMC demonstrates its efficacy and safety as a controlled drug delivery method for antibiotics like cefixime.

Thermo-amplifier circuit in probiotic E. coli for stringently temperature-controlled release of a novel antibiotic.

Peptide drugs have seen rapid advancement in biopharmaceutical development, with over 80 candidates approved globally. Despite their therapeutic potential, the clinical translation of peptide drugs is hampered by challenges in production yields and stability. Engineered bacterial therapeutics is a unique approach being explored to overcome these issues by using bacteria to produce and deliver therapeutic compounds at the body site of use. A key advantage of this technology is the possibility to control drug delivery within the body in real time using genetic switches. However, the performance of such genetic switches suffers when used to control drugs that require post-translational modifications or are toxic to the host. In this study, these challenges were experienced when attempting to establish a thermal switch for the production of a ribosomally synthesized and post-translationally modified peptide antibiotic, darobactin, in probiotic E. coli. These challenges were overcome by developing a thermo-amplifier circuit that combined the thermal switch with a T7 RNA Polymerase. Due to the orthogonality of the Polymerase, this strategy overcame limitations imposed by the host transcriptional machinery. This circuit enabled production of pathogen-inhibitory levels of darobactin at 40°C while maintaining leakiness below the detection limit at 37°C. Furthermore, the thermo-amplifier circuit sustained gene expression beyond the thermal induction duration such that with only 2h of induction, the bacteria were able to produce pathogen-inhibitory levels of darobactin. This performance was maintained even in physiologically relevant simulated conditions of the intestines that include bile salts and low nutrient levels.

Sodium Alginate/Poly (Acrylicacid) Hydrogel Composite, Potential Carrier for Fibroblast Growth Factor1 (FGF1) Delivery.

Fibroblast growth factor1 is a powerful signaling molecule that plays a critical role in injury repair of diverse tissue by stimulating cell growth and angiogenesis. FGF1 has significant role in the cell fate and regulating inflammation with short half-life and poor in vivo stability. The encapsulation of the growth factor in the hydrogel led to peptide protect from the degradation and/or immune recognition and enable controlled drug delivery over a longer period of time. The aim of this study is to develop and evaluate a hydrogel carrier with adjustable release rate while maintaining bioactivity of FGF1. Here we describe an optimal ratio of sodium alginate and polyacrylic acid without additional cross linker containing optimum amount of FGF1 with the potential of sustained release to be used as a therapeutic agent. The carrier was characterized by FTIR, contact angle and swelling ratio. The activity of FGF1 after release from the hydrogel was confirmed by ELISA and Western blot. Further assessment of genes related to inflammation were evaluated by RTPCR. This hydrogel is able to deliver growth factors by restricting the essential proteins within the matrix to prevent rapid proteolysis and explosive release and is therefore widely applicable.

Poly(ionic liquid)-Based Hydrogel for Emerging Pollutant Removal and Controlled Drug Delivery

Poly(ionic liquid)-Based Hydrogel for Emerging Pollutant Removal and Controlled Drug Delivery

Comparative Study of pH-Responsive and Aggregation Stability of Bosutinib-Loaded Nanogels Comprising Gelatin Methacryloyl, Carboxymethyl Dextran, and Hyaluronic Acid for Controlled Drug Delivery in Colorectal Cancer: An Extensive In Vitro Investigation.

This study investigates the use of pH-responsive nanogels for delivering Bosutinib (BOSU) in colon cancer treatment. Nanogels were formulated using three polymers: hyaluronic acid (HA), carboxymethyl dextran (CMD), and gelatin methacryloyl (GelMA). These nanogels achieved high drug entrapment efficiencies (80-90%) through polymer mixing with BOSU, followed by EDC/NHS cross-linking and sonication. The nanogels were stable, with negative zeta potentials (-20 to -30 mV) and particle sizes between 100 and 200 nm. Fourier-transform infrared analysis confirmed successful methacrylation in GelMA nanogels. Sustained BOSU release at pH 5.0 was observed, resembling tumor environments, compared to slower release at normal pH (7.4). Cytotoxicity tests showed 70-80% cell survival reduction in HCT116 colon cancer cells at higher doses, and GelMA-BOSU nanogels notably reduced cell migration. Antiangiogenic effects were confirmed in a chick chorioallantoic membrane model, highlighting the potential of these nanogels for targeted BOSU delivery in colon cancer therapy.

Self‐Driving Lab for Solid‐Phase Extraction Process Optimization and Application to Nucleic Acid Purification

Sorptive bioprocesses are the basis for numerous biotechnological applications such as enzyme immobilization, biosensors, controlled drug delivery, water treatment, and molecular purification. Yet due to the complexity of these processes, their optimization is still time, labor, and cost‐intensive. This research presents a flexible self‐driving laboratory (SDL) designed for the accelerated development and optimization of solid‐phase extraction processes. As a use case, the SDL was used to optimize a DNA purification process using silica magnetic beads. Through the integration of robotics, machine learning, and data‐driven experimentation, the SDL demonstrates a highly accelerated process optimization with minimal human intervention. In the multistep purification approach, the system is able to optimize buffer compositions for DNA extraction from complex samples, demonstrating effectiveness in both conventional chaotropic salt‐based methods and innovative chaotropic salt‐free buffers. The study highlights the SDL's capability to autonomously refine process parameters, achieving significant enhancements in yield and purity of the product. This blueprint for future self‐driving optimization of bioprocess parameters showcases the potential of autonomous systems to revolutionize biochemical process development, offering insights into scalable, environmentally sustainable, and cost‐effective solutions.

Modulating Drug Retention and Release via Surface Anchors Using Hyperthermia and Photothermal Effects of Fe3O4-SiO2 Core-shell Mesoporous Nanoparticles

Core-shell nanocarriers (Fe3O4-MSN-TESPA-PEG/DOX) with a core-shell structure were created as possible materials for controlled drug retention and release. With a notable increase in pore volume and surface area, the 3-(Trimethylsilyl)propionic acid (TESPA) anchors on the pore walls of SiO2 nanoparticles (MSN). The doxorubicin (DOX) is controlled and stored by a network of polyethylene glycol (PEG) layers that cover the MSN pore by TESPA anchor as a result of interactions between the layers and the high density of functional groups at the pore mouth. Rather than the Brownian motion contribution, magnetic hysteresis losses account for the magnetic hyperthermia contribution to the heating efficiency of the investigated core-shell configuration. Fe3O4 NPs' magnetism and capacity for photothermal conversion make its core an appealing choice for photothermal treatment. By appropriately adjusting the following variables, the combination of magnetic field and NIR irradiation can control localized heating: i. NIR irradiation density; ii. magnetic field intensity; iii. time of use; and iv. concentration of Fe3O4-MSN-TESPA-PEG/DOX core-shell solution. This combination is ideal for bioapplications and clinical trials. The two-step NIR irradiation procedure or magnetic field intensity control allows for the rapid delivery of roughly seven times the maximum amount of stored doxorubicin in only five minutes. Fe3O4-MSN-TESPA-PEG nanocarriers with their core-shell structure have great potential as therapeutic agents with controllable drug delivery and targetability.

Advancements in cyclodextrin-based controlled drug delivery: Insights into pharmacokinetic and pharmacodynamic profiles

Advancements in cyclodextrin-based controlled drug delivery: Insights into pharmacokinetic and pharmacodynamic profiles

In Silico Drug Encapsulation Using 2-Hydroxypropyl-β-CD, Tyrosine Kinase and Tyrosinase Inhibition of Dinuclear Cu(II) Carboxylate Complexes

In recent years, copper carboxylate complexes have garnered significant interest for biological applications. This study focuses on 20 Cu(II) carboxylate complexes selected from our previous research. Due to the hydrophobic nature of these complexes, the 2-hydroxypropyl-β-cyclodextrin (2HPβCD) was employed as a carrier to reduce toxicity and increase solubility for controlling drug delivery. Monte Carlo calculations were performed to confirm the interaction between the optimized structures of Cu(II) complexes and 2HPβCD, forming a host-guest system. All the structures were simulated and optimized using DFT-D calculations in Material Studio 2017. The results indicated that a neutral medium is more favorable for the adsorption of these complexes into 2HPβCD. More negative binding energy values suggested strong and energetically favorable adsorption on 2HPβCD. Complexes 4, 5, and 7 exhibited the highest interaction, making them excellent candidates for drug delivery systems. DFT-D calculations were also used to investigate the release of complexes, revealing that complexes 5, 14, and 19 were difficult to release due to their lowest energy. In contrast, complexes 8, 9, and 16 were found to be most efficient to release due to weak non-covalent interactions with 2HPβCD as we can predict from binding energy obtained by DFT-D. No specific trend was observed in the interaction of the complexes with 2HPβCD. Additionally, the effects of these complexes on c-kit tyrosine kinase and Mushroom tyrosinase were studied by molecular docking. The results demonstrated that all the complexes interacted with the active site of respective receptors through hydrophobic interactions. Complexes containing 1,10-phenanthroline and 2,2-bipyrdine were identified as having a strong, spontaneous binding ability with receptors.

Enzyme-induced degradation of natural and artificial linear polyanions

Synthetic and natural polymers are widely used for constructing drug delivery systems. Biocompatibility, water solubility and non-toxicity make polymers a convenient matrix for encapsulation, delivery and release of bioactive compounds [1–6]. Coupling of a drug with a biodegraded polymer matrix is a promising way for a controlled drug delivery. Along this line, the degradation of the four polymers in the presence of two enzymes in aqueous solutions was investigated. The following polymers were used: natural polysaccharides, sodium alginate and sodium hyaluronate, artificial (modified) sodium carboxymethylcellulose and synthetic sodium polyacrylate (control); their degradation was caused by the addition of alginate lyase and hyaluronidase. The first enzyme only cleaved the specific alginate substrate and left three other intact. Contrastingly, the second enzyme degraded all three polysaccharides, including artificial carboxymethylcellulose, but did not degrade synthetic polyacrylate. The biodegradation of polymers was accompanied by decreasing the size of polymer particles in solution from 100-200 nm down to 20-30 nm; the latter are capable of removing from the body through the kidneys. The initial polysaccharides showed the negative surface charge in aqueous solution, which changed but retained negative after biodegradation. The initial and biodegraded polysaccharides demonstrated negligible cytotoxicity during long exposure period. The obtained results are valuable for the development of polymer carriers for drug encapsulation and delivery.

Effect of material properties and extrusion process parameters on permeability of etonogestrel in ethylene vinyl acetate copolymer (EVA) films

Ethylene vinyl acetate copolymers (EVA) have been extensively used in controlled drug delivery systems due to its good biocompatibility and tunable applicability based on simple variations in vinyl acetate (VA) content. We investigated impacts of material properties of EVA, including VA content and molecular weight, as well as extrusion process parameters, including draw down ratio and cooling rate, on permeability of etonogestrel in EVA films. Among all factors studied, the VA content was the most dominant factor that controls drug permeability by affecting crystallinity of EVA. MW, DDR, and cooling rate exhibited less significant effects. The impacts of these factors on crystallinity, crystallite size, and degree of crystalline orientation of EVA were characterized using polarized light microscope, differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS). Based on the solution-diffusion model, the mechanisms by which the crystalline properties controlled drug solubility and diffusivity in EVA were discussed. These results can be applied to investigate the effects of material properties of EVA and manufacturing process conditions on drug release properties of reservoir-type EVA-based drug delivery systems with a rate-controlling membrane.

Novel Applications in Controlled Drug Delivery Systems by Integrating Osmotic Pumps and Magnetic Nanoparticles.

The alarming rise in chronic diseases worldwide highlights the urgent need to overcome the limitations of conventional drug delivery systems. In this context, osmotic pumps are able to release drugs by differential osmotic pressure, achieving a controlled rate independent of physiological factors and reducing the dosing frequency. As osmotic pumps are based on the phenomenon of osmosis, the choice of high osmolality draw solutions (DSs) is a critical factor in the successful delivery of the target drug. Therefore, one alternative that has received particular attention is the formulation of DSs with magnetic nanoparticles (MNPs) due to their easy recovery, negligible reverse solute flux (RSF), and their possible tailor-made functionalization to generate high osmotic gradients. In this work, the possible integration of DSs formulated with MNPs in controlled drug delivery systems is discussed for the first time. In particular, the main potential advantages that these novel medical devices could offer, including improved scalability, regeneration, reliability, and enhanced drug delivery performance, are provided and discussed. Thus, the results of this review may demonstrate the potential of MNPs as osmotic agents, which could be useful for advancing the design of osmotic pump-based drug delivery systems.

Enhancing Antibacterial Properties of Titanium Implants through Covalent Conjugation of Self-Assembling Fmoc-Phe-Phe Dipeptide on Titania Nanotubes.

Bacterial infections and biofilm formation are significant challenges for medical implants. While titanium nanotube engineering improves biocompatibility, it cannot prevent bacterial adhesion and biofilm formation. Optimizing the biomaterial's surface chemistry is vital for its desired functioning in the biological environment. This study demonstrates the covalent conjugating of the self-assembling dipeptide N-fluorenylmethyloxycarbonyl-diphenylalanine (Fmoc-FF) onto titanium nanotube surfaces (TiNTs) without altering the topography. Fmoc-FF peptides, in conjugation with TiNTs, can inhibit biofilm formation, eradicate pre-existing biofilms, and kill bacteria. This functionalization imparts antibacterial properties to the surface while retaining beneficial nanotube topography, synergistically enhancing bioactivity. Surface characterization by XPS, FT-IR, EDS, and SEM confirmed the successful functionalization. Bacterial adhesion experiments showed a significantly improved antibacterial activity of the functionalized TiNT surfaces. This study opens future possibilities for associating biomedical applications such as cell-cell interactions, tissue engineering, and controlled drug delivery of multifunctional self-assembling short peptides with implant materials through surface functionalization.

Revolutionizing Eye Care: Exploring the Potential of Microneedle Drug Delivery

Microneedle technology revolutionizes ocular drug delivery by addressing challenges in treating ocular diseases. This review explores its potential impact, recent advancements, and clinical uses. This minimally invasive technique offers precise control of drug delivery to the eye, with various microneedle types showing the potential to penetrate barriers in the cornea and sclera, ensuring effective drug delivery. Recent advancements have improved safety and efficacy, offering sustained and controlled drug delivery for conditions like age-related macular degeneration and glaucoma. While promising, challenges such as regulatory barriers and long-term biocompatibility persist. Overcoming these through interdisciplinary research is crucial. Ultimately, microneedle drug delivery presents a revolutionary method with the potential to significantly enhance ocular disease treatment, marking a new era in eye care.

Poly(vinyl alcohol)/Chitosan Hydrogel Containing Gallic Acid-Modified Fe, Cu, and Zn Metal-Organic Frameworks (MOFs): Preparation, Characterization, and Biological Applications.

Hydrogel composites are water-swollen and three-dimensional materials that have been investigated for various biological applications, including controlled drug delivery and tissue engineering, owing to the similarity between their mechanical, electrical, and chemical properties with biological tissues. The hydrogel composites can provide a superior replication of living tissue compared to their single components. In this regard, Fe-BTC, Cu-BTC, and Zn-BTC MOFs were synthesized and modified with gallic acid (GA). The MOFs-based hydrogel composites (M-BTC-GA@PVA-CS) were finally fabricated by freezing-thawing the as-synthesized MOFs, gallic acid, chitosan, and poly(vinyl alcohol) mixture. The obtained hydrogels were characterized using techniques such as FTIR, XRD, UV-vis, SEM, EDS, and TEM. Additionally, their antibacterial activity against E. coli and S. aureus and biocompatibility were investigated. The results showed that the surface modification of M-BTC MOFs with GA improves the antibacterial performance of hydrogels and increases their biocompatibility and cell viability. Among the as-prepared M-BTC MOF-based composites, the Cu-BTC MOF-loaded hydrogels showed the highest antibacterial activity. In contrast, the lowest antibacterial effect was observed for the hydrogels with Fe-BTC MOFs. Furthermore, the H&E staining exhibited improved vascularization in Zn-BTC-GA@PVA-CS and Cu-BTC-GA@PVA-CS scaffolds compared to the Fe-BTC-GA@PVA-CS hydrogel. These MOFs-loaded hydrogels may be suitable for utilization in biological applications such as skin treatment, drug delivery, and cosmetics owing to their excellent antibacterial activity and low cytotoxicity.

Local Controlled Delivery of IL-4 Decreases Inflammatory Bone Loss in a Murine Model of Periodontal Disease.

Chronic inflammatory diseases are a leading global health problem. In many of these diseases, the consistent presence of systemic low-grade inflammation induces tissue damage. This is true in conditions such as diabetes, arthritis, and autoimmune disorders, where an overactive and uncontrolled host immune response is a major driver of immunopathology. Central to this overactive and destructive host response are macrophages, the major phagocytic cells within the innate immune system. These cells exhibit a dual role in both host defense against invading pathogens and promotion of tissue repair during inflammation resolution. Those unique characteristics make macrophages an excellent target for therapeutic interventions in many chronic inflammatory conditions. Using periodontal disease as a model of chronic inflammation, we sought to assess the feasibility of using a controlled drug delivery strategy to target macrophages within the oral cavity. To that end, IL-4 was encapsulated within a biodegradable polymer carrier and locally delivered into the inflamed periodontal tissues. Our data indicate that local sustained delivery of IL-4 decreased inflammatory bone loss and promoted bone gain in the diseased mouse periodontium. Those effects correlated with a shift of local macrophage population toward a prorepair phenotype. Using single-cell RNA sequencing technology, we found that IL-4 delivery reversed several proinflammatory pathways associated with tissue destructive macrophages. Together, our data suggest that sustained delivery of IL-4 may be a viable therapeutic option for chronic diseases characterized by immune-mediated tissue damage.

Unveiling the influence of oxygen on drug release dynamics in semipermeable polymersomes.

Semipermeable polymersomes, a class of polymeric vesicles that allow molecular passage across their membranes, offer significant potential for controlled drug delivery. These vesicles can be designed for inherent or selective permeability through the choice of suitable copolymers or the incorporation of protein nanopores, respectively. In this study, we explore a novel approach using oxygen-producing enzymatic reactions within biodegradable poly(ethylene glycol)-poly(caprolactone-gradient-trimethylene carbonate) (PEG-p(CL-g-TMC)) polymersomes to modulate drug release. These polymersomes were found to enhance the release of hydrophobic drugs while retaining hydrophilic drugs. The enzymatic generation of oxygen within the polymersomes increased membrane hydrophobicity, influencing drug release kinetics. The findings highlight the importance of understanding drug release kinetics in designing effective drug delivery systems, as the release rate and mechanism critically impact therapeutic efficacy and patient outcomes.

Proteins-Based Nanoparticles for Benznidazole Enteric Delivery.

Chagas disease, caused by Trypanosoma cruzi (T. cruzi), affects millions worldwide, particularly in Latin America. Despite its prevalence, treatment options remain limited. Current drugs, such as benznidazole, cause adverse effects possibly due to ineffective administration. In this context, nanoparticles offer a promising solution to target and control drug delivery by leading the effector site and minimizing side effects. This article focuses on zein-casein-based nanoparticles (Bioparticles, BP) coated with Eudragit L100-55 (BP:EU) for enteric delivery of benznidazole. BP:EU structures are synthesized to minimize premature drug release in the stomach, promoting release in the small intestine. Physical characterization confirmed the successful synthesis of BP:EU and their pH-responsive trigger for drug release. These findings suggest that this material can be a promising approach for Chagas disease treatment, addressing challenges in benznidazole delivery that can lead to improved therapeutic responses.

Phase-separated polymer blends for controlled drug delivery by tuning morphology

Controlling drug release rate and providing physical and chemical stability to the active pharmaceutical ingredient are key properties of oral solid dosage forms. Here, we demonstrate a formulation strategy using phase-separated polymer blends where the morphology provides a route for tuning the drug release profile. By utilising phase separation of a hydrophobic and a hydrophilic polymer, the hydrophilic component will act as a channelling agent, creating a porous network upon dissolution that will dictate the release characteristics. With ptychographic X-ray tomography and scanning transmission X-ray microscopy we reveal how the morphology depends on both polymer fraction and presence of drug, and how the drug is distributed over the polymer domains. Combining X-ray imaging results with dissolution studies reveal how the morphologies are correlated with the drug release and showcase how tuning the morphology of a polymer matrix in oral formulations can be utilised as a method for controlled drug release.