Stimuli-responsive Properties Research Articles

Nitroxide-Containing Poly(2-oxazoline)s Show Dual-Stimuli-Responsive Behavior and Radical-Trapping Activity.

2,2,6,6-Tetramethylpiperidine-N-oxyl (TEMPO) structures possess potent antioxidant activities for biomedical applications. TEMPO immobilization on hydrophilic polymers is a powerful strategy to improve its properties; however, it is mostly limited to reversible-deactivation radical polymerizations or postpolymerization approaches. Here, we immobilized TEMPO units on a hydrophilic poly(2-ethyl-2-oxazoline) (PEtOx) backbone through cationic ring-opening polymerization (CROP) of a new 2-oxazoline monomer bearing a methoxy-protected TEMPO 2-substituent with 2-ethyl-2-oxazoline (EtOx). The ratios of EtOx/TempOx were adjusted to optimize the nitroxide content while maintaining suitable water solubility of the resulting P(EtOxx-stat-TempOx-Oy•) copolymers upon deprotection. P(EtOx40-stat-TempOx-O10•) and P(EtOx33-stat-TempOx-O17•) showed a dual stimuli-responsive behavior and demonstrated significant radical-trapping activities in aqueous media. Particularly, a meaningful augmentation in the activity of TempOx-O• was observed when it was immobilized as P(EtOxx-stat-TempOx-Oy•). The P(EtOx40-stat-TempOx-O10•) system exhibited a longer-lasting activity in water, statistically comparable to that of the antioxidant ferrostatin-1 (Fer-1). Overall, this study introduces a biocompatible polymeric platform for TEMPO immobilization that augments its radical-trapping activity and offers controllable stimuli-responsive properties.

Design of functional and stable adhesion systems using reversible and movable crosslinked materials

Abstract Stable, tough, and functional adhesion systems are urgently needed for a sustainable society. As a resolution, supramolecular scientists have introduced reversible and movable crosslinked materials into adhesion systems. Reversible crosslinks can repeatedly associate and dissociate. Therefore, reversible crosslinked materials show self-healing and stimuli-responsive properties. Moreover, movable crosslinks are topological crosslinks in which the polymer chains penetrate the cavities of cyclic molecules. The sliding of the movable crosslinks with deformation enabled the achievement of materials showing high toughness and self-relaxation. Adhesion systems with reversible and movable crosslinks have improved adhesion and cohesion, stability, and functionality. This novel concept for the design of adhesion systems is expected to increase the lifetime of adhesives and ameliorate environmental problems.

Hierarchically Structured Stimuli-Responsive Liquid Crystalline Terpolymer-Rhodamine Dye Conjugates.

Optically responsive materials are applied in sensing, actuators, and optical devices. One such class of material is dye-doped liquid crystal polymers that self-assemble into cholesteric mesophases that reflect visible light. We report here the synthesis and characterization of a family of linear and mildly crosslinked terpolymers prepared by the ROMP of norbornene-based monomers. The three monomers were composed of (i) rhodamine dye through one or two norbornene end groups utilizing flexible C10-alkane spacers, (ii) a cholesteryl liquid crystal (LC) using C9-alkane spacers, and (iii) PEG side chains. We investigated how these architectural variations in these terpolymers impacted their hierarchically self-assembled mesophase properties. We probed their composition, morphology, thermal, mechanic, photochromic, and mechanochromic properties using, inter alia, 1H NMR spectroscopy, DSC, temperature-dependent SAXS, diffuse reflectance UV-vis spectroscopy, and optical polarization microscopy. The new terpolymers exhibited architecture-dependent thermochromic, mechanochromic, and piezochromic properties arising from LC-rhodamine dye interactions. We found that a compromise between the rigidity and flexibility of the terpolymer architectures needed to be stricken to fully express stimuli-responsive properties. These terpolymers also showed distinctly different properties compared to those of a previously reported structurally related liquid crystalline copolymer made from two monomers. These findings help to define the design principles for optimally stimuli-responsive liquid crystalline polymers.

Chromic Electrospun Polymer Nanofibers: Preparation, Applications, and the Future.

Physical understanding and determination of different analytes without the need for advanced and additional equipment are highly important, which can be achieved by using stimuli-induced chromic materials. Physical and chemical incorporation of responsive chromophores into different polymers results in the fabrication of chromic polymers. Chromic electrospun nanofibers are prepared using the electrospinning technique, and their stimuli-responsivity is improved due to their high surface-to-volume ratio. This Perspective focuses on recent studies and developments on stimuli-induced chromic electrospun nanofibers. Within this Perspective, these nanofibers are divided into different classes of photochromic, thermochromic, electrochromic, mechanochromic, halochromic, solvatochromic, hydrochromic, and ionochromic according to the stimuli to which they respond. In addition, the preparation methods, chromic compounds, electrospinning conditions, response mechanisms, and different applications of chromic nanofibers will be discussed. The main applications of such chromic nanofibers are food packaging sensors, health monitoring sensors, anticounterfeiting materials, ink-free rewritable media, and smart clothing. Several new strategies are also proposed for different applications in future studies. The preparation of multiresponsive nanofibers that combine different chromic properties in a single system and also multifunctional nanofibers that merge stimuli-responsive chromic properties with other smart functionalities can be considered in the future. This Perspective aims to assist researchers and scientists in the preparation and development of new multifunctional chromic electrospun nanofibers for advanced applications, including multimode anticounterfeiting materials, multiresponsive sensors for food packaging, and shape memory-assisted dual-mode encryption of important data.

Intelligent responsive nanogels: New Horizons in cancer therapy.

Biologically engineered nanogels formed through sophisticated intramolecular crosslinking processes represent the forefront of next-generation drug delivery systems. These innovative systems offer many advantages, like adjustable size, satisfactory biocompatibility, and minimal toxicity. Their unique attributes facilitate deep penetration and long-term retention of drugs in tumors, effectively enhancing the anti-tumor effects. Nonetheless, the rapid disintegration of nanogels and the subsequent triggering of drug release at the tumor site pose significant challenges in achieving more effective and precise tumor treatments. Therefore, increasing research has been dedicated to exploring stimulus-responsive nanogels for enhancing tumor therapy. This review aims to encapsulate the research advancements in emerging stimulus-responsive antitumor nanogels. Firstly, a detailed exposition is provided on various endogenous stimulus-responsive nanogels, encompassing factors such as pH, hypoxia, enzymes, reactive oxygen species (ROS), and glutathione (GSH). Secondly, various nanogels triggered by exogenous stimuli such as light, ultrasound, temperature, and magnetic fields are elaborately presented. Furthermore, nanogels with multifaceted stimulus-responsive properties are also skillfully designed. Finally, the future directions, application prospects, and challenges of intelligent responsive nanogels in cancer treatment are highlighted.

Phosphorescent Sensor Based on Iridium(III) Complex with Aggregation-Induced Emission Activity for Facile Detection of Volatile Acids.

Phosphorescent sensors are essential for rapid visual sensing of volatile acids, due to their profound impact on ecosystems and human health. However, solid phosphorescent materials for acid-base stimulus response are still rare, and it is important to achieve real-time monitoring of volatile acids. In order to obtain an efficient and rapid response to volatile acid stimulation, N-H and -NH2 substituents are introduced into an auxiliary ligand to synthesize a new cationic Ir(III) complex (Ir-NH). The AIE property of Ir-NH leads to enhanced emission in the aggregated state, which facilitates the construction of solid-state acid-base sensors. More importantly, due to the introduction of -NH2 and N-H in the molecular structure, reversible switching of the emission color of Ir-NH under acid-base stimulation was successfully achieved. A convenient and efficient sensing device for volatile acid monitoring was prepared using Ir-NH as the active material. Our results provide a new strategy for designing phosphorescent materials with AIE and acid-base stimulus-responsive properties.

Bent-shaped dimers with chiral spacer – unravelling the potential of the naphthyl mesogenic unit

ABSTRACT Chiral liquid-crystalline dimers are becoming increasingly significant for fundamental research and practical applications due to their unique mesomorphism resulting in specific optical and stimuli-responsive properties. Here, we describe the mesomorphic and chiral properties of a novel series of racemic and corresponding chiral bent-shaped dimers featuring a chiral flexible spacer, which differ in the position and number of naphthyl groups within the mesogenic units. The synthesised dimers exhibit racemic and chiral forms of the nematic (N/N*) and twist-bend nematic (NTB/N*TB) phases. Incorporating the naphthyl group enhances the stability of both nematic phases and promotes the formation of a chiral hierarchical structure in the N*TB phase. Dimers with a naphthyl group adjacent to the chiral centre demonstrate a much shorter helical pitch of the N* phase and higher helical twisting power (HTP) than those with a phenyl group in the same position. Moreover, they show temperature-dependent helix inversion, a phenomenon rarely observed in liquid crystalline materials with a single chiral centre. Our findings reveal that the incorporation of the naphthyl moiety in our chiral dimer structures not only enhances stability but also imparts unique properties, making these dimers promising candidates for further research and potential applications.

Subtle Molecular Engineering around Flavin core for Stimuli-Responsive Solid-State Luminophore.

The present manuscript discusses the design, synthesis, and stimuli-responsive solid-state properties of two novel flavin analogues, Phenyl Flavin (PhFl) and Pyridinyl Flavin (PyFl), featuring covalently linked phenyl and pyridinyl rings to isoalloxazine. Stimuli-responsive properties of PhFl and PyFl were examined, where PyFl displayed more pronounced and reversible emissive behavior in the solid state in response to external stimuli. To elucidate the mechanism underlying the mode for switching behavior, single crystal- and powder-X-ray diffraction, as well as differential scanning calorimetry studies, were performed. Furthermore, a simple dip-in method was used to demonstrate its usage as ink free rewritable material.

Stimuli-responsive carrageenan-based biomaterials for biomedical applications.

Carrageenan-based biomaterials have attracted considerable attention in recent years due to their unique biological properties, including their biodegradability, compatibility, and lack of adverse effects. These biomaterials exhibit a variety of beneficial properties, such as antiviral, antitumor, and immunomodulatory effects, which set them apart from other polysaccharides. Stimuli-responsive carrageenan-based biomaterials have attracted particular attention due to their unique properties such as reducing systemic toxicity and controlling drug release. In this review, a comprehensive investigation of stimuli-responsive carrageenan-based biomaterials was conducted under the influence of various stimuli such as pH, electric field, magnetic field, temperature, light, and ions. These structures exhibited good stimulus-responsive properties and involved corresponding physical and chemical changes, such as changes in swelling ratio and gelling power, etc. The biomedical application of carrageenan-based stimuli-responsive biomaterials in the field of tissue engineering, anticancer, antibacterial, and food monitoring has been investigated, showing the great potential of these structures. Although there are promising developments in the design and use of stimuli-responsive carrageenan-based biomaterials, further research is advisable to further investigate their potential applications, particularly in animal models. Extensive studies are needed to investigate the benefits and limitations of these materials to ensure their safety and effective use in biomedical applications.

Colorimetric detection of anionic surfactant using polydiacetylene/zinc (II)/zinc oxide nanocomposites with unique yellow-to-red color transition

Polydiacetylenes (PDAs) have extensively received attention as colorimetric sensors because of their stimulus-responsive properties. This contribution presents a simple technique to modify polydiacetylene/zinc (II) ion/zinc oxide (PDA/Zn2+/ZnO) nanocomposites for colorimetric detection of an anionic surfactant. Incorporation of cetyltrimethylammonium bromide (CTAB) into the nanocomposite structure is achieved through a simple mixing process in an aqueous medium. Interestingly, the resultant PDA/Zn2+/ZnO-CTAB sensors exhibit a unique yellow-to-red color change in response to the anionic surfactant, sodium dodecyl sulfate (SDS). Furthermore, the colorimetric detection of SDS at different concentrations can be achieved by varying the added CTAB concentrations. The detectable concentration range of SDS in this study extends from 0.3 to 7 mM. Our study offers a simple and low-cost method to fabricate colorimetric sensors for anionic surfactant detection using PDA materials.

Circularly polarized luminescence in chiral nematic liquid crystals based on photochromic molecules

Circularly polarized luminescence (CPL) has emerged as a focal point in luminescent materials research, reflecting a growing field of study. Responding to the demand for practical applications across diverse sectors, there is a critical need for CPL materials with high luminescence dissymmetry factors (g lum) and adjustable optical performance, driving the development of novel materials and methodological approaches. Chiral nematic liquid crystals (N*-LCs) have attracted significant attention as promising candidates for producing high-performance CPL materials due to their ability to exhibit enhanced g lum and modulate circularly polarized light. This review comprehensively presents the stimuli-responsive CPL properties, utilizing N*-LCs as chiral templates doped with various photochromic compounds, particularly azobenzene, spiropyran (SP), diarylethene and overcrowded alkene. By elucidating the dynamic interplay between molecular structure, supramolecular organization, and optical response, it offers a profound understanding of the stimuli-responsive CPL behaviors. Additionally, the review also explores the multifaceted applications of photochromic N*-LCs materials, spanning advanced display technologies, optical data storage, and beyond. By examining diverse avenues for leveraging their unique optical properties, it highlights their pivotal role in driving innovation across photonic applications, facilitating transformative advancements in the field.

Translating Solid-Phase Conformational Memory in the Prophecy of Multi-stimuli Responsive Low Molecular Weight Gels.

Polymorphism and its screening to select the best-performing form is in high demand. In low molecular weight organogels (LMWG), gelators are designed as they contain flexible groups, functionalities capable of varied H-bonding, and increased the potential to show polymorphism. We synthesized a bis-urea based LMWG G1 and isolated three distinct polymorphic phases (Form I, II, and III). G1 polymorphs showed noticeable differences in solubility; precisely, Form I is highly soluble compared to the other two. Gel screening was carried out for all three polymorphs using different stimuli like heat-cool, sonication, shaking, and grinding. Among the polymorphs, Form I was found to have better gelling ability which was reflected by the solvent scope, thermal stability (gel-sol transition temperature Tgel), minimum gelator concentration (M.G.C.), stimuli-responsiveness, morphology, and rheological properties. The differences in their gelation performance among the three polymorphs are associated with their solubility parameter. Stimuli like sonication, shaking, and grinding triggered Form I to form a gel. Form II and III responded to heat-cool stimuli only due to poor solubility. Therefore, it is noted crucial to add polymorph screening as an integral part of the gel synthesis to avoid problems associated with reproducibility in the gel prophecy of LMWG systems.

Side-Chain Engineering of Boron β-Dialdiminate Homopolymer for Solvent-Dependent Emission Properties.

Luminescent materials that respond to changes in microscopic chemical conditions are essential for visualizing and evaluating molecular environments. Boron complexes are often employed as robust scaffolds for constructing such responsive systems because of their inherent stimuli-responsive properties. However, in the case of nonresponsive luminophores, the absence of these intrinsic features limits their range of applications. In this study, environment-responsive luminescent homopolymers based on the boron β-dialdiminate complex are developed, which is intrinsically less responsive, by introducing optimized side chains. As a key finding, the triethylene glycol-decorated polymer exhibits more intense luminescence in chloroform but weaker luminescence in N,N-dimethylformamide. Structural analyses using NMR and size-exclusion chromatography suggest that this polymer forms larger aggregates in polar solvents because of the solvophobicity of its main chain, while the polar side chains assist in maintaining adequate dispersibility of these aggregates. Photophysical measurements indicate that interchromophore interactions within the aggregates should be responsible for the reduced luminescence in polar solvents. These findings suggest that side-chain engineering should be an effective strategy for creating stimuli-responsive polymers from otherwise nonresponsive luminophores.

Insight into the effect of terminal aromatic group on the mesomorphic, emissive and stimuli-responsive properties of cyanostyrene-based derivatives with multiple applications

Three novel series of cyanostyrene-based derivatives containing pyridine, cyanostyrene and terminal phenyl, naphthyl and anthryl as π-conjugated aromatic unit were synthesized by Suzuki coupling and Knoevenagel reactions. A slight modification in chemical structures induced significant differences in self-assembly property in bulk state, emissive properties in both solution and aggregated states, mechanochromic properties and acidochromism properties. The terminal phenyl cyanostyrene-based derivatives exhibited a mesophase transition from nematic phase to smectic A phase upon elongation of the terminal chain and decreasing temperature, whereas the other terminal naphthyl and anthryl cyanostyrene-based derivatives were non-mesogen, which might be attributed to the increased twisted molecular configuration and geometric anisotropy. All the compounds displayed positive solvatochromic behaviors and the redshift in emission spectra gradually increased from terminal naphthyl compound via phenyl compound to anthryl compound attributing to the enhancement in intramolecular charge transfer. All the compounds displayed emission in both solution and aggregated states due to the twisted molecular configurations or/and distinct intramolecular charge transfer. The terminal phenyl and naphthyl compounds displayed extremely weak mechanochromism, whereas the terminal anthryl compound displayed distinct mechanochromism due to the highly twisted molecular configuration of the anthryl compound. Reversible high-contrast acidochromism was realized for all the compounds due to the reversible protonation and deprotonation process of pyridine. In addition, the good applications in security paper, encrypted ink and bioimaging were also demonstrated. This investigation elucidates that a slight change in chemical structures could induce big differences in characteristics in different states, which afforded effective ways for the construction of multifunctional materials.

Recent advances of self-assembled nanoparticles in the diagnosis and treatment of atherosclerosis.

Atherosclerosis remains a significant global health challenge, with its related conditions as the leading cause of death, underscoring the urgent need for enhanced diagnostic and therapeutic approaches. Recently, self-assembled nanoparticles (SANPs) have shown remarkable promise in treating atherosclerosis, attributed to their superior bioavailability, biodegradability, biocompatibility, and ease of functional modification. Numerous SANP variants, such as DNA origami, metal-organic frameworks (MOFs), nanozymes, peptide-based nanoparticles, and self-assembled prodrug nanoparticles, have been engineered, extending their utility in targeted drug delivery and imaging. Advances in fabrication technologies, including microfluidic techniques, allow for precise and scalable SANP production, while innovative nanoparticle designs-such as stimuli-responsive and carrier-free variants-enhance pharmacokinetic properties. The deployment of SANPs in atherosclerosis has introduced a range of diagnostic and therapeutic solutions, from non-invasive imaging and stimuli-responsive drug delivery to vaccination, theranostics, and biosensing. This review consolidates the recent progress in SANP applications for atherosclerosis, emphasizing their transformative potential in disease management.

Creation of Excitation-Driven Hypervalent Tin(IV) Compounds For Aggregation-Induced Emission and Application to Thermoresponsive Luminescent Films Below Freezing Point.

Although many researchers have devoted their much effort to establish the strategy for developing a stimuli-responsive molecule and tuning of their properties according to the preprogrammed design, it is still challenging to create desired molecules from the scratch. We recently demonstrated that the molecules with a large structural difference between the theoretically optimized structures in the ground and excited states have a potential to exhibit stimuli-responsive luminescent properties. We defined these molecules as an excitation-driven molecule and have shown that they are a versatile platform for designing stimuli-responsive luminescent molecules. Herein, based on the concept of excitation-driven molecules, we show that the hypervalent tin-fused azomethine (TAm) compounds possessing aggregation-induced emission (AIE) properties can be obtained by simple chemical modification with a methyl group although conventional TAm derivatives are well known to be highly luminescent compounds in solution. Furthermore, by combining the solid-state luminescence property of AIE and the coordination number shifts of the hypervalent tin atom, the thermoresponsive films operating below the freezing point are fabricated with the polymer. In this study, we apply the concept of excitation-driven molecules to the hypervalent compounds and demonstrate to obtain the novel functional materials.

PH-induced morphological reversible transition from microparticles to vesicles for effective bacteria entrapment

Polymer particles with stimuli-responsive properties offer promising applications in healthcare, chemical reactors, development of artificial cells and organelles, as well as in the entrapment of bacteria. In this study, a novel biocompatible, biodegradable, and pH-responsive diblock copolymer based on polylactide (PLA) and poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) was synthesized via a metal-free one-pot/simultaneous ring-opening polymerization (ROP) and reversible addition-fragmentation chain transfer (RAFT) approach (ROP/RAFT). This copolymer was then employed to produce highly monodisperse microparticles using microfluidics droplet generation technique. Utilizing confocal microscopy imaging, a reversible pH-induced morphological transition from microparticles to vesicle-like structures was observed at pH 5.1. The reversible shift in morphology from microparticles to giant vesicles (Vs) in acidic environments is triggered by the protonation of amino groups of the PDPA block, rendering vesicle surfaces positively charged − an advantageous feature for attracting and engulfing negatively charged bacteria. Initial validation involved electrostatic interactions with negatively charged latex resin beads followed by assessing interaction capabilities with gram-negative bacteria, Escherichia coli (E. coli). Additionally, the reversible morphological transition of microparticles-to-vesicles was employed to study drug release at different pHs. This approach proven to be a promising strategy for targeted drug delivery and bacteria entrapment using smart pH-responsive microparticles.

Stable Porous Organic Cage Nanocapsules for pH-Responsive Anticancer Drug Delivery for Precise Tumor Therapy.

The search for drug nanocarriers with stimuli-responsive properties and high payloads for targeted drug delivery and precision medicine is currently a focal point of biomedical research, but this endeavor still encounters various challenges. Herein, a porous organic cage (POC) is applied to paclitaxel (PTX) drug delivery for cancer therapy for the first time. Specifically, water-soluble, stable, and biocompatible POC-based nanocapsules (PTX@POC@RH40) with PTX encapsulation efficiency over 98% can be synthesized by simply grafting nonionic surfactant (Polyoxyl 40 hydrogenated castor oil, RH40) on the POC surface. These PTX@POC@RH40 nanocapsules demonstrate remarkable stability for more than a week without aggregation and exhibit pH-responsive behavior under acidic conditions (pH 5.5) and display sustained release behavior at both pH 7.4 and pH 5.5. Intravenous administration of PTX@POC@RH40 led to a 3.5-fold increase in PTX bioavailability compared with the free PTX group in rats. Moreover, in vivo mouse model experiments involving 4T1 subcutaneous breast cancer tumors revealed that PTX@POC@RH40 exhibited enhanced anticancer efficacy with minimal toxicity compared with free PTX. These findings underscore the potential of POCs as promising nanocarriers for stimuli-responsive drug delivery in therapeutic applications.

Optical and Chiroptical Stimuli-Responsive Chiral AgNPs@H-Leu-Poly(phenylacetylene) Nanocomposites in Water.

Dynamic macroscopically chiral nanocomposites are prepared by combining silver nanoparticles (AgNPs) and dynamic helical poly(phenylacetylene)s (PPAs) bearing pendants functionalized with amino groups. These amino groups provide the nanocomposite with the ability to disperse in water along with high stability due to the interaction between the ammonium group and the AgNP. Moreover, the equilibrium between NH3+/NH2 produces a "blinking" contact between the PPA and the AgNPs, which allows total control of the dynamic helical behavior of the polymer. The use of acidic or neutral pH allows controlling the morphology of the nanocomposite, which consists of a nanosphere that has trapped inside it a single AgNP (pH = 2) or several AgNPs (pH = 7) with ca. 30 nm of diameter. These nanocomposites combine the optical and chiroptical stimuli-responsive properties of both components, AgNPs and PPAs. Thus, the controlled aggregation of the nanocomposite produced variations in the LSPR band of the AgNPs in a reversible manner. In turn, given that the chiral coating is selective to Ba2+, the presence of this metal ion caused a helical inversion of the chiral coating of the nanocomposite detected by electronic circular dichroism. Moreover, it is possible to distinguish between three metal ions in different oxidation states, such as Ce4+, Fe3+, and Hg2+, which produce different responses of the nanocomposite when oxidizing the AgNP to Ag+.

Role of Natural Polymers in Novel Drug Delivery Systems

Natural polymers have gained significant attention in the field of drug delivery due to their inherent biocompatibility, biodegradability, and low toxicity. This review article aims to provide a comprehensive overview of the diverse roles that natural polymers play in the development of novel drug delivery systems. Beginning with a classification of natural polymers based on their origin (plant, animal, microbial), we explore their unique characteristics and advantages over synthetic counterparts. The review discusses the pivotal role of natural polymers in formulating various drug delivery systems, including sustained/controlled release formulations, targeted delivery platforms, mucoadhesive systems, and nanotechnology-based approaches. Techniques such as emulsification, ionotropic gelation, coacervation, and electrospinning for natural polymer-based drug delivery are elucidated, highlighting their versatility and applicability across different administration routes. Furthermore, we delve into the diverse applications of natural polymers in drug delivery, encompassing oral, transdermal, ocular, injectable, nasal, buccal, and vaginal delivery routes. Recent advances and innovations in combining natural polymers with synthetic counterparts, incorporating stimuli-responsive properties, and personalized medicine approaches are also explored. Despite the numerous advantages offered by natural polymers, challenges such as variability in polymer properties, standardization issues, scale-up challenges, and regulatory considerations are discussed. The review concludes with future perspectives, highlighting emerging trends and opportunities for further research and development in the field of natural polymer-based drug delivery systems. Overall, this review provides valuable insights into the pivotal role of natural polymers in advancing drug delivery technology, paving the way for safer, more efficient, and patient-friendly therapeutic interventions.