Drug Release Applications Research Articles

From Cellulose Solutions to Aerogels and Xerogels: Controlling Properties for Drug Delivery.

A cheap and easy-to-recycle solvent, namely, aqueous NaOH with no additives, was used to dissolve cellulose and make cross-linker-free materials with varying porosity, testing them as drug delivery devices. Cellulose solutions were gelled, coagulated in a nonsolvent (water, ethanol), and dried either using supercritical CO2 (aerogels) or low-vacuum evaporation (named "xerogels"). Aerogels had densities of around 0.1 g/cm3 and specific surface areas (SSAs) of 200-400 m2/g. A significant influence of the first nonsolvent and drying mode on material properties was recorded: when the first nonsolvent was ethanol and low-vacuum drying was performed from ethanol, aerogel-like xerogels were obtained with densities of around 0.2 g/cm3 and SSAs of 200-260 m2/g. Other conditions (under evaporative drying) resulted in cellulose with much lower porosity and SSA. All materials were evaluated as drug delivery devices in simulated gastrointestinal fluids; theophylline was used as a model drug. Materials of high porosity exhibited shrinking and rapid drug release, whereas denser materials swelled and showed slower release. Two release mechanisms were suggested: diffusion through aqueous media in pores and diffusion through swollen pore walls. The results demonstrate a large spectrum of options for tuning the properties of porous cellulose materials for drug release applications.

Drug-eluting contact lenses: Progress, challenges, and prospects.

Topical ophthalmic solutions (eye drops) are becoming increasingly popular in treating and preventing ocular diseases for their safety, noninvasiveness, and ease of handling. However, the static and dynamic barriers of eyes cause the extremely low bioavailability (<5%) of eye drops, making ocular therapy challenging. Thus, drug-eluting corneal contact lenses (DECLs) have been intensively investigated as a drug delivery device for their attractive properties, such as sustained drug release and improved bioavailability. In order to promote the clinical application of DECLs, multiple aspects, i.e., drug release and penetration, safety, and biocompatibility, of these drug delivery systems were thoroughly examined. In this review, we systematically discussed advances in DECLs, including types of preparation materials, drug-loading strategies, drug release mechanisms, strategies for penetrating ocular barriers, in vitro and in vivo drug delivery and penetration detection, safety, and biocompatibility validation methods, as well as challenges and future perspectives.

Effects of Secondary Structures and pH on the Self-Assembly of Poly(ethylene glycol)-b-polytyrosine.

Different from conventional synthetic polymers, polypeptides exhibit a distinguishing characteristic of adopting specific secondary structures, including random coils, α-helixes, and β-sheets. The conformation determines the rigidity and solubility of polypeptide chains, which further direct the self-assembly and morphology of the nanostructures. We studied the effect of distinct secondary structures on the self-assembly behavior of polytyrosine (PTyr)-derived amphiphilic copolymers. Two block copolymers of enantiopure poly(ethylene glycol)-b-poly(l-tyrosine) (PEG-b-P(l-Tyr)) and racemic poly(ethylene glycol)-b-poly(dl-tyrosine) (PEG-b-P(dl-Tyr)) were synthesized through the ring-opening polymerization of l-tyrosine N-thiocarboxyanhydride (l-Tyr-NTA) and dl-tyrosine N-thiocarboxyanhydride (dl-Tyr-NTA), respectively, by using poly(ethylene glycol) amine as the initiator. PEG44-b-P(l-Tyr)10 adopts a β-sheet conformation and self-assembles into rectangular nanosheets in aqueous solutions, while PEG44-b-P(dl-Tyr)9 is primarily in a random coil conformation with a tiny content of β-sheet structures, which self-assembles into sheaf-like nanofibrils. A pH increase results in the ionization of phenolic hydroxyl groups, which decreases the β-sheet content and increases the random coil content of the PTyr segments. Accordingly, PEG44-b-P(l-Tyr)10 and PEG44-b-P(dl-Tyr)9 self-assemble to form slender nanobelts and twisted nanoribbons, respectively, in alkaline aqueous solutions. The secondary structure-driven self-assembly of PTyr-derived copolymers is promising to construct filamentous nanostructures, which have potential for applications in controlled drug release.

Statistically based mechanical model of shape memory hydrogels

The constitutive models of shape memory hydrogels (SMHs) are gaining increasing interest due to their important applications in human tissue, artificial skin, and drug release because these models can elucidate the interaction between water molecule diffusion and transient network deformation, and clarify the mechanism of shape memory effect. Herein, based on the chain statistic theory, a micro-macroscopic SMH constitutive model is developed, which simultaneously considers solvent diffusion and network evolution. Compared with existing models, our model considers the coupling effect of water molecule diffusion and dynamic network deformation, kinetics of dynamic bond controlled by temperature, chemical potential and chain force, and can capture the location-dependent shape memory effect of SMHs. In addition, this model is implemented into ABAQUS through a user material subroutine (UMAT) and the simulation results are in reasonable agreement with experimental measurements. Three simulation examples, the constrained swelling of a strip, deformation of a flat plate with a hole and SMH indentation, are presented and simulation results indicate that our model can capture the location-dependent shape memory behaviors. This work provides a powerful tool to elucidate complex mechanical behaviors of SMHs and may guide their structure designs and applications.

The effect of PEGylation components on drug release behavior of targeted reduced graphene oxide based drug delivery system

Reduced graphene oxide (rGO) is a restored, defect-free version of graphene oxide (GO) with regained graphene-like properties but encounters challenges in biomedical applications due to its low solubility. Especially for drug release applications, rGO’s stronger π-π interaction of rGO compared to GO leads to low release, often demanding novel approaches for enhancement. The recently developed PEGylation method utilizes a copolymer with tunable PEG chain length and density for the PEGylation of GO simultaneously reduced to rGO, resulting in water-dispersible and biocompatible rGO-based nanoplatforms. This copolymer integrates functional monomers and enhances treatment options. Herein, we investigated how these PEGylation components and their incorporation order impact rGO’s drug release behavior. A series of copolymers, (P(PEGMA-co-AzPMA-co-MMA-co-PMA), with different PEG brushes and azide groups, were synthesized via atom transfer radical polymerization. We explored the impact of ionic azide groups on drug release by comparing the azide-containing and azide-capped copolymers. Moreover, copolymers containing 500 or 2000 Da PEG brushes were compared to assess their role as a coating layer or diffusion barrier on drug release. Doxorubicin, a hydrophobic anticancer agent, was loaded onto the rGO surface before or after peptide-based targeting agent (EPPT1) conjugation. The results showed that the drug release behavior of 500 or 2000 Da PEG brushes containing rGO surfaces are different due to the density of PEG coating which makes the effect of azide groups not always visible. Incorporating the targeting peptide before drug loading was found to be optimal. The pH-dependent release profiles revealed 49 % and 44 % release from the rGO surface for the shorter and longer PEG brushes, respectively. Tuning the PEGylation components may further influence the release behavior.

Plasmonic photothermal therapy based synergistic drug release application through gold nanoparticles coated and embedded PLGA nanoparticles

Drug carrier structures based on the biocompatible polymer Poly(D-lactic-co-glycolic acid) (PLGA) are considered traditional delivery systems. To increase the potential of PLGA nanoparticle (NP)-based carriers for use in near infrared radiation (NIR)-based photothermal drug release applications, two important approaches are the combined use of gold nanoparticles with PLGA NPs structures. In this study, AuNPs were prepared both decorated on PLGA NPs and embedded in PLGA NPs structures. The particles were prepared and characterized for their structural and thermal properties using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Differential Scanning Calorimetry (DSC) methods. Morphological features and size distributions were also determined using Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS). Thermal changes caused by plasmonic particles under 808 nm NIR laser were examined using a thermal camera for spherical gold nanoparticle (AuNP) and star-shaped gold nanoparticle (AuNS). The most suitable increase in temperature has been obtained in the AuNS structures. Epirubicin (EPI) release studies were conducted using PLGA NPs embedded with AuNS, employing NIR and an ON/OFF based approach. Basic toxicological evaluations of these particles were performed on mouse fibroblast (L929) cells to assess biocompability properties. The study also investigated the impact of prepared EPI-loaded particles and laser-controlled drug release on cytotoxicity, ROS production, and genotoxicity, in human neuroblastoma (SH-SY5Y) cells. The results indicated that the activity of EPI-loaded AuNP@PDOP@PLGA NPs increases synergistically with the ON/OFF-based approach, as shown by the calculated combination index (CI) value. The developed combination approach shows promise for further evaluation before clinical use.

Acoustofluidics enables direct ink writing of vascular scaffolds with intrinsically patterned porous microstructures

Vascular scaffolds with well-organized pore characteristics are crucial for promoting infiltration, adhesion, growth, tissue-specific arrangement, and substance-exchanges of biological cells. However, their controllable fabrication is extremely challenging, especially for those with specially designed three-dimensional (3D) tubular and porous microstructures. In this paper, a new methodology based on acoustofluidics-assisted direct ink writing (DIW) technique is developed to fabricate vascular scaffolds with controlled porosity distributions and well-defined porous microstructures. Calcium carbonate (CaCO3) particles and alginate are uniformly mixed as the printing ink, which is printed along a rotating rod to form a vessel-like structure. Distributions of these CaCO3 particles in the printed structure are precisely controlled using bulk acoustic waves. The particles within the vessel-like structure are dissolved in situ using hydrochloric acid, resulting in the formation of 3D vascular scaffolds with intrinsically patterned porous microstructures. The scaffolds printed by the acoustofluidics-assisted DIW method exhibit a 69% improvement in pore connectivity compared to conventional 3D-printed scaffolds. Fibroblast cells are successfully seeded onto these scaffolds, achieving distinctive distributions along the patterned porous microstructures. This innovative methodology, with its excellent microfabrication capabilities, holds great promise for applications in tissue engineering, drug release, composite formation, microfluidic chips, and biosensors.

Fabrication of biocompatible water-soluble supramolecular nanofibers of oseltamivir with methyl-β-cyclodextrin for enhanced drug release

In recent times, there has been a growing interest in the advancement of nanofiber technology using materials based on cyclodextrin (CD). This heightened interest is primarily driven by their potential applications in controlled drug release. This research aims to create the nanofibers (NF) which involves incorporating an antiviral agent, oseltamivir (OTV) into the CD cavity, forming inclusion complexes (IC) that greatly improve drug encapsulation efficiency. To assess the physicochemical properties and drug-loading capabilities of these CD-based NF, a variety of characterization techniques can be utilized. It is noteworthy that NF containing OTV:MCD-IC/PVA demonstrates a continuous release of OTV (89.25%) at acidic conditions (pH 5.8) when compared to NF holding no MCD materials. Moreover, dissolution studies reveal that the resulting material is non-toxic and readily soluble in water (less than 2 min). MTT assay indicated that the examined NF are completely safe and do not have/make any adverse effects on the cells (cell viability is more than 98%). The fibroblast cells grown on nanomatrixes composed of both OTV/PVA and OTV:MCD IC/PVA NF did not display any indications of apoptosis or nuclear shrinkage. The development of such systems holds significant promise for advancing therapeutic strategies in the management of viral infections.

Exploring the Effectiveness of Carboxymethylated and Crosslinked Albizia procera Gum in Diltiazem Hydrochloride Matrix Tablets: A Comparative Analysis.

This study investigates the efficacy of modified Albizia procera gum as a release-retardant polymer in Diltiazem hydrochloride (DIL) matrix tablets. Carboxymethylated Albizia procera gum (CAP) and ionically crosslinked carboxymethylated Albizia procera gum (Ca-CAP) were utilized, with Ca-CAP synthesized via crosslinking CAP with calcium ions (Ca2+) using calcium chloride (CaCl2). Fourier Transform (FT) IR analysis affirmed polymer compatibility, while differential scanning calorimetry (DSC) and X-ray diffraction (XRD) assessed thermal behavior and crystallinity, respectively. Zeta potential analysis explored surface charge and electrostatic interactions, while rheology examined flow and viscoelastic properties. Swelling and erosion kinetics provided insights into water penetration and stability. CAP's carboxymethyl groups (-CH2-COO-) heightened divalent cation reactivity, and crosslinking with CaCl2 produced Ca-CAP through -CH2-COO- and Ca2+ interactions. Structural similarities between the polymers were revealed by FTIR, with slight differences. DSC indicated modified thermal behavior in Ca-CAP, while Zeta potential analysis showcased negative charges, with Ca-CAP exhibiting lower negativity. XRD highlighted increased crystallinity in Ca-CAP due to calcium crosslinking. Minimal impact on RBC properties was observed with both polymers compared to the positive control as water for injection (WFI). Ca-CAP exhibited improved viscosity, strength, controlled swelling, and erosion, allowing prolonged drug release compared to CAP. Stability studies confirmed consistent six-month drug release, emphasizing Ca-CAP's potential as a stable, sustained drug delivery system over CAP. Robustness and accelerated stability tests supported these findings, underscoring the promise of Ca-CAP in controlled drug release applications.

Chemical and Photochemical-Driven Dissipative Fe3+/Fe2+-Ion Cross-Linked Carboxymethyl Cellulose Gels Operating Under Aerobic Conditions: Applications for Transient Controlled Release and Mechanical Actuation.

A Fe3+-ion cross-linked carboxymethyl cellulose, Fe3+-CMC, redox-active gel exhibiting dissipative, transient stiffness properties is introduced. Chemical or photosensitized reduction of the higher-stiffness Fe3+-CMC to the lower-stiffness Fe2+-CMC gel, accompanied by the aerobic reoxidation of the Fe2+-CMC matrix, leads to the dissipative, transient stiffness, functional matrix. The light-induced, temporal, transient release of a load (Texas red dextran) and the light-triggered, transient mechanical bending of a poly-N-isopropylacrylamide (p-NIPAM)/Fe3+-CMC bilayer construct are introduced, thus demonstrating the potential use of the dissipative Fe3+-CMC gel for controlled drug release or soft robotic applications.

Abstract 5800: Ultrasound-mediated nano-drug delivery system to enhance cancer treatment efficacy: An in vitro study

Abstract Conventional non-targeted nano-sized drug delivery systems face limitations such as restricted drug penetration depth and treatment efficacy in solid tumors. External stimulus such as ultrasound waves can trigger targeted, on-demand drug release from the nanocarriers. We demonstrate a first-of-its-kind use of low-intensity pulsed ultrasound (LIPUS) to induce Doxorubicin release from the surface of gold nanoparticle drug carriers. Our 1-MHz LIPUS beam is capable of penetrating tissue to sufficient depths with the required power/intensity for drug release applications with a nominal intensity of around 3 W/cm2 in the region of interest (ROI). This level of intensity is necessary to elevate the tissue temperature to the mild hyperthermia range of 41 to 45 °C. Our in vitro experiments demonstrate a remarkable 22% enhancement in drug release with the addition of LIPUS. Measurements of drug release kinetics, with and without LIPUS, suggest that LIPUS shifts the drug release mechanisms from static (Fickian) to dynamic (non-Fickian) release in vitro. Thus, revealing the intricate interactions between ultrasound and drug release from gold nanoparticle drug carriers. To assess the efficacy of the delivery system, we developed an in vitro cell culture model with a customized ultrasound exposure setup. The LIPUS device was situated at the bottom base of a water tank, directing ultrasound beam upward toward a region of interest where the MDA-MB-231 breast cancer cells were located 35 mm away from the LIPUS element. We found that the LIPUS device operating at an acoustic power of around 4 W increased cell killing efficacy by approximately 15% ± 2% when compared to conventional nano-drug delivery, highlighting a significant improvement attributed to ultrasound-induced mechanical effects. At the cellular level, these results underscore the potential advantages of ultrasound-mediated nano-drug delivery over conventional chemotherapy and non-targeted nano-drug delivery. Citation Format: Farshad Moradi Kashkooli, Anshuman Jakhmola, Tyler K. Hornsby, Graham A. Ferrier, Jahangir (Jahan) Tavakkoli, Michael C. Kolios. Ultrasound-mediated nano-drug delivery system to enhance cancer treatment efficacy: An in vitro study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5800.

Programming the Assembly of Oligo-Adenine with Coralyne into a pH-Responsive DNA Hydrogel.

External stimuli-responsive DNA hydrogels present interesting platforms for drug loading and triggered release. Typically, drug molecules are encapsulated within three-dimensionally hybridized DNA networks. However, the utilization of drug molecules as cofactors to facilitate the directed assembly of DNA strands into hydrogel frameworks and their subsequent controlled release remains to be explored. Herein, we introduce the guided assembly of oligo-adenine (A-strand) into an acidic pH-responsive DNA hydrogel using an anticancer drug, coralyne (COR), as a low-molecular-weight cofactor. At pH 7, COR orchestrates the assembly of A-strand into an antiparallel duplex configuration cross-linked by A-COR-A units at a stoichiometric ratio of one COR cofactor per four adenine bases, resulting in a DNA hydrogel characterized by A-COR-A duplex bridges. At pH 4-5, the instability of A-COR-A units results in the disintegration of the duplex into its constituent components, leading to the release of COR and simultaneous dissociation of the DNA hydrogel matrix. This study introduces a method by which drug molecules, exemplified here by COR, facilitate the direct formation of a supramolecular cofactor-DNA complex, subsequently leading to the creation of a stimuli-responsive DNA hydrogel. This approach may inspire future investigations into DNA hydrogels tailored for controlled drug encapsulation and release applications.

Aldehyde group pendant-grafted pectin-based injectable hydrogel

Periodate oxidation has been the widely accepted route for obtaining aldehyde group-functionalized polysaccharides but significantly influenced the various physicochemical properties due to the ring opening of the backbone of polysaccharides. The present study, for the first time, presents a novel method for the preparation of aldehyde group-functionalized polysaccharides that could retain the ring structure and the consequent rigidity of the backbone. Pectin was collected as the representative of polysaccharides and modified with cyclopropyl formaldehyde to obtain pectin aldehyde (AP), which was further crosslinked by DL-lysine (LYS) via the Schiff base reaction to prepare injectable hydrogel. The feasibility of the functionalization was proved by FT-IR and 1H NMR techniques. The obtained hydrogel showed acceptable mechanical properties, self-healing ability, syringeability, and sustained-release performance. Also, as-prepared injectable hydrogel presented great biocompatibility with a cell proliferation rate of 96 %, and the drug-loaded hydrogel exhibited clear inhibition of cancer cell proliferation. Overall, the present study showed a new method for the preparation of aldehyde group-functionalized polysaccharides, and the drug-loaded hydrogel has potential in drug release applications.

PH/Ion Dual-Responsive Emulsion Via a Cationic Surfactant and Positively Charged Magnesium Hydroxide Nanosheets.

Emulsions, formed by dispersing a liquid into another immiscible one by virtue of emulsifiers, have been widely applied in commercial applications like foods, pharmaceuticals, cosmetics, and personal care, which always confront environmental and/or toxic questions due to emulsifiers' high dosage. Recently, a study on Pickering emulsions points out a solution to stable emulsions based on the costabilizing effect of colloidal particles, which focused on surface-active particles cooperating with oppositely charged ionic surfactants. Costabilized emulsions adopting a charge-similar ionic surfactant and particles were less studied. In this article, a hexane-in-water emulsion was prepared in use of a cationic surfactant cetyltrimethylammonium bromide (CTAB) with positively charged magnesium hydroxide (MH) nanosheets at low concentrations (10-5 M and 10-2 wt %, respectively). The emulsion is stable due to the synergy by CTAB and MH nanosheets, which functions in virtue of the electric repulsion by similarly charged particles, the mechanical shielding by MH nanosheets, and restrained water drainage in lamellae between droplets due to the gelation of MH nanosheets. Moreover, the emulsion is doubly switchable within emulsification/demulsification via convenient pH or ion manipulation, a mechanism based on the breakdown and rebuilding of the costabilizing synergy. Such dual-responsive emulsions show high potential for the delicate control of drug delivery, release, and biphasic biocatalysis applications.

Synthesis and characterization of poly (acrylamide‐co‐acrylic acid)/chitosan (derived from fish scales) for controlled release of amoxicillin drug

AbstractChitosan (CS) can be extracted from waste fish scales through a series of chemical processes, including demineralization, deproteinization, and deacetylation. The biomaterial poly (acrylamide [AM]‐co‐acrylic acid [AA])/CS is a unique superabsorbent material synthesized through the free radical graft copolymerization method by using AM, AA, and CS powder. During synthesis, ammonium persulfate is used as an initiator, and N, N′‐methylene bisacrylamide is used as a cross‐linker. Scanning electron microscopy and Fourier transform infrared spectroscopy have been studied to know about the morphology and structure of the synthesized superabsorbent materials. The water absorbency of the material continuously increases from day 1 to day 30. The thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) of the superabsorbent material show adequate thermal stability. The X‐ray diffraction (XRD) analysis indicates that the synthesized biomaterial is virtually amorphous in nature. The percentage of biodegradability increases with time. The encapsulation efficiency of amoxicillin drugs is around 70%, which indicates that the biomaterial is highly efficient for drug release applications. The synthesized novel biomaterial is a low‐cost, eco‐friendly, and thermally stable hydrogel that can be effectively used in drug release applications.Highlights Chitosan (CS)‐based hydrogels are highly pH‐sensitive towards drug release. The biodegradability and swelling behavior of the synthesized biomaterial were studied by adopting a suitable methodology. The novel material formed was characterized by using Fourier transform infrared spectroscopy, TGA, and Scanning electron microscopy. The encapsulation efficiency, kinetic study, and controlled drug release behavior of the amoxicillin drug were studied in solutions of simulated gastric fluid and phosphate‐buffered saline. The material developed in this study shows good performance in controlled drug delivery, and is therefore suitable for manufacturing medical devices used in drug delivery.

Wet-Spun Chitosan-Sodium Caseinate Fibers for Biomedicine: From Spinning Process to Physical Properties.

We designed and characterized chitosan-caseinate fibers processed through wet spinning for biomedical applications such as drug delivery from knitted medical devices. Sodium caseinate was either incorporated directly into the chitosan dope or allowed to diffuse into the chitosan hydrogel from a coagulation bath containing sodium caseinate and sodium hydroxide (NaOH). The latter route, where caseinate was incorporated in the neutralization bath, produced fibers with better mechanical properties for textile applications than those formed by the chitosan-caseinate mixed collodion route. The latter processing method consists of enriching a pre-formed chitosan hydrogel with caseinate, preserving the structure of the semicrystalline hydrogel without drastically affecting interactions involved in the chitosan self-assembly. Thus, dried fibers, after coagulation in a NaOH/sodium caseinate aqueous bath, exhibited preserved ultimate mechanical properties. The crystallinity ratio of chitosan was not significantly impacted by the presence of caseinate. However, when caseinate was incorporated into the chitosan dope, chitosan-caseinate fibers exhibited lower ultimate mechanical properties, possibly due to a lower entanglement density in the amorphous phase of the chitosan matrix. A standpoint is to optimize the chitosan-caseinate composition ratio and processing route to find a good compromise between the preservation of fiber mechanical properties and appropriate fiber composition for potential application in drug release.

Programmable Photoswitchable Microcapsules Enable Precise and Tailored Drug Delivery from Microfluidics.

The development of precision personalized medicine poses a significant need for the next generation of advanced diagnostic and therapeutic technologies, and one of the key challenges is the development of highly time-, space-, and dose-controllable drug delivery systems that respond to the complex physiopathology of patient populations. In response to this challenge, an increasing number of stimuli-responsive smart materials are integrated into biomaterial systems for precise targeted drug delivery. Among them, responsive microcapsules prepared by droplet microfluidics have received much attention. In this study, we present a UV-visible light cycling mediated photoswitchable microcapsule (PMC) with dynamic permeability-switching capability for precise and tailored drug release. The PMCs were fabricated using a programmable pulsed aerodynamic printing (PPAP) technique, encapsulating an aqueous core containing magnetic nanoparticles and the drug doxorubicin (DOX) within a poly(lactic-co-glycolic acid) (PLGA) composite shell modified by PEG-b-PSPA. Selective irradiation of PMCs with ultraviolet (UV) or visible light (Vis) allows for high-precision time-, space-, and dose-controlled release of the therapeutic agent. An experimentally validated theoretical model was developed to describe the drug release pattern, holding promise for future customized programmable drug release applications. The therapeutic efficacy and value of patternable cancer cell treatment activated by UV radiation is demonstrated by our experimental results. After in vitro transcatheter arterial chemoembolization (TACE), PMCs can be removed by external magnetic fields to mitigate potential side effects. Our findings demonstrate that PMCs have the potential to integrate embolization, on-demand drug delivery, magnetic actuation, and imaging properties, highlighting their immense potential for tailored drug delivery and embolic therapy.

A Comprehensive Review on the Development of Transdermal Patches for Sustained Release of Medication in Migraine Therapy

This extensive review study focuses on the developments and difficulties in the creation of transdermal patches for the treatment of migraines. Migraine is a common neurological condition marked by crippling headaches and frequently need early and effective treatment. A potential method for sustaining medication administration, transdermal patches provide regular dose and boost patient compliance. The composition of transdermal patches, the method of drug release, benefits, drawbacks, and potential applications in the treatment of migraines are all covered in this article.

Design of multi-responsive and actuating microgels toward on-demand drug release.

Multifunctional colloidal microgels that exhibit stimuli-responsive behaviour and excellent biocompatibility have attracted particular attention for developing functional compartmentalized networks. Herein, a series of stimuli-responsive microgels (M0, M1, and M2) were designed through the copolymerization of di(ethylene glycol) methyl ether methacrylate (DEGMA) and methacrylic acid (MAA) monomers using hydroxy ethyl methacrylate-coupled azobenzene (HEMA-Az) and ethylene glycol dimetharylate (EGDMA) as crosslinkers. The behaviour of the microgels in response to temperature, pH, and light was thoroughly investigated using spectroscopic, microscopic, and light-scattering techniques. Interestingly, the microgels deswelled with an increase in temperature, decrease in pH, and under the irradiation of UV light. Such a reversible swelling/deswelling behaviour was exploited for microgel M2, which showed better photoactuation at pH 5 with a higher fluid pumping velocity. The actuating microgel M2 was optimized for loading the drug ciprofloxacin (Cf) to study its release at different temperature, pH, and light conditions. Microgel M2 exhibited photoresponsive Cf release at pH 5 and 37 °C, demonstrating its potential for application in on-demand drug release.

Nanoparticle‐based sustained drug delivery for the treatment of ocular neovascular diseases

Aims/Purpose: Nanoparticles have shown great potential as a drug delivery system for the treatment of neovascular ocular diseases characterized by the growth of abnormal blood vessels in the retina. The current standard of therapy for neovascular ocular diseases involves administering monoclonal antibody‐based anti‐VEGF drugs via intravitreal injections on a periodic basis. The short half‐lives of these drugs necessitate frequent injections, which can limit the effectiveness of the treatments. Hence, there is a need to develop new approaches for enhanced bioavailability and sustained and long‐lasting delivery of anti‐VEGF drugs. The aim of this study was to utilize poly (glycerol sebacate) (PGS) nanoparticles to achieve an extended release of anti‐VEGF (anti‐vascular endothelial growth factor) drugs, with the objective of reducing the frequency of intravitreal injections required for treatment.Methods: Double emulsion solvent evaporation method was utilized for the synthesis of PGS nanoparticles. Nanoparticle size and polydispersity index (PDI) were determined with dynamic light scattering method.Results: Nanoparticles were synthesized with a size of approximately 150 nm and PDI less than 0.3. The encapsulation efficiency of nanoparticles loaded with anti‐VEGF drugs was found to be 74%. The 30% drug release from nanoparticles in the first 2 months indicates that nanoparticles are a promising candidate for sustained drug release applications. Cell‐viability studies showed that anti‐VEGF drug‐loaded nanoparticles did not exhibit toxicity to ARPE‐19 cells, but they did exhibit anti‐angiogenesis properties by inhibiting the growth of HUVEC cells in a concentration‐dependent manner.Conclusions: The development of new‐generation materials for the storage and preservation of anti‐VEGF drugs, as well as their enhancement with prolonged release, will considerably improve the efficacy of long‐term treatment strategies for ocular neovascular diseases.