Multilayered mucoadhesive hydrogel films based on Ocimum basilicum seed mucilage/thiolated alginate/dopamine-modified hyaluronic acid and PDA coating for sublingual administration of nystatin

Challenges and improvements in multi-layer mucosa-adhesive films for oral diseases treatment and prognosis

Due to the complexity of oral physiology and pathology, the treatment of oral diseases faces multiple and complex clinical requirements. Mucosa-adhesive films (MAFs) with a single layer have demonstrated considerable potential in delivering therapeutic bioactive ingredients directly to the site of oral diseases. However, their functions are often hindered by certain factors such as limited loading capacity, poor site specificity, and sensitivity to mechanical stimuli. To overcome these limitations, the development of multi-layer MAFs has become a focal point for recent research. This involves the improvement of construction methods for multi-layer MAFs to minimize potential health risks from residual solvents, and conducting comprehensive in vivo studies to evaluate their safety and therapeutic efficacy more accurately, thus paving the way for their commercialization. Additionally, the exploration of multi-layer MAFs as personalized drug delivery systems could further broaden their application prospect. Precisely, multi-layer MAFs compensate for the shortcomings of current therapeutic strategies for oral diseases to a great extent, indicating a promising future in the market.

Particle Size-Tunable Polydopamine Nanoparticles for Optical and Electrochemical Imaging of Latent Fingerprints on Various Surfaces

Powder dusting method is the most widely used approach due to its low cost, simplicity, minimal instrument dependence, and extensive applicability for developing latent fingerprints (LFPs). Herein, a novel optical and electrochemical dual-mode method for high-resolution LFP enhancement has been explored based on size-tunable polydopamine (PDA) nanoparticles (NPs) and scanning electrochemical microscopy (SECM). Dark PDAs rich in functional groups and negative charges can combine with the residues of LFPs on various surfaces with high sensitivity and selectivity to realize high-resolution visual fingerprint physical patterns on various porous and nonporous substrates with light color. However, optical visualization is not feasible for LFPs on dark or multicolored surfaces. Fortunately, based on the differences in electrochemical reactivity between ridges and furrows caused by the conductivity and reducibility of PDA powders, SECM can serve as a powerful supplement to optical methods to effectively overcome background color interference and distinctly display fingerprint patterns. Intriguingly, it is noteworthy that the binding amount and particle size of PDA powder significantly affected the optical and electrochemical visualization of LFPs: more powder binding amounts provided darker ridges in optical, and more surface reaction sites (larger powder binding mass at the same particle size or smaller particle size at the same mass) provided higher currents of ridges in electrochemical imaging. It demonstrates that the PDA powder as a dual-mode developer for LFPs offers a promising method for individual identification in forensics.

Stimuli-responsive glucuronoxylan polysaccharide from quince seeds for biomedical, food packaging, and environmental applications

Mucilage is a gelatinous mixture of polysaccharides secreted from the seed coat and/or pericarp of many plant seeds when soaked in water. Mucilage affected seed germination while maintaining hydration levels during scarcity. Cydonia oblonga (quince) seeds are natural hydrocolloids extruding biocompatible mucilage mainly composed of polysaccharides. Quince seed mucilage (QSM) has fascinated researchers due to its applications in the food and pharmaceutical industries. On a commercial scale, QSM preserved the sensory and physiochemical properties of various products such as yogurt, desserts, cakes, and burgers. QSM is responsive to salts, pH, and solvents and is mainly investigated as edible coatings in the food industry. In tablet formulations, modified and unmodified QSM as a binder sustained the release of various drugs such as cefixime, capecitabine, diclofenac sodium, theophylline, levosulpiride, diphenhydramine, metoprolol tartrate, and acyclovir sodium. QSM acted as a reducing and capping agent to prepare nanoparticles for good antimicrobial resistance, photocatalytic characteristics, and wound-healing potential. The present review discussed the extraction optimization, chemical composition, stimuli-responsiveness, and viscoelastic properties of mucilage. The potential of mucilage in edible films, tissue engineering, and water purification will also be discussed.

Mussel-inspired polydopamine modified mica with enhanced mechanical strength and thermal performance of poly(lactic acid) coating

Polylactic acid (PLA), as a green functional polymer, has been useful in various coating applications. However, due to the low mechanical strength and thermal stability of PLA, it needs to be improved in order to expand its application areas. In this work, a series of polylactic acid (PLA) nanocomposite films were prepared through introducing polydopamine-modified mica (PDA@MICA) as a self-assemble nanofiller to enhance its mechanical and thermal properties. The results demonstrated that PLA/PDA@MICA shows excellent mechanical properties. Tensile tests showed that PLA/PDA@MICA exhibits a 58.3 % increase in tensile strength and a 16.8 % increase in Young's modulus compared to pure PLA. Meanwhile, thermal performance testing shown the introduction of PDA@MICA led to an increase in crystallinities (Xc = 24.78 %). And the thermal decomposition temperature of PLA/PDA@MICA film (374 °C) was slightly higher than that of PLA film (367 °C). The simultaneous improvement of the mechanical and thermal properties was attributed to the formation of hydrogen bonds between PLA and PDA@MICA. In addition, the parallel arrangement of PDA@MICA and PLA macromolecular chains forms a unique "brick and mortar" structure in the coating, which enhances the mechanical properties of PLA/PDA@MICA composite coatings. This study reports a successful approach to simultaneously address the drawbacks of PLA, specifically its low thermal stability and mechanical strength, thereby promoting its widespread application in the coatings industry.

Oral Films Printed with Green Propolis Ethanolic Extract

Oral film (OF) research has intensified due to the effortless administration and advantages related to absorption in systemic circulation. Chitosan is one of the polymers widely used in the production of OFs; however, studies evaluating the maintenance of the active principles' activity are incipient. Propolis has been widely used as an active compound due to its different actions. Printing techniques to incorporate propolis in OFs prove to be efficient. The objective of the present study is to develop and characterize oral films based on chitosan and propolis using printing techniques and to evaluate the main activities of the extract incorporated into the polymeric matrix. The OFs were characterized in relation to the structure using scanning and atomic force electron microscopy; the mechanical properties, disintegration time, wettability, and stability of antioxidant activity were evaluated. The ethanolic extract of green propolis (GPEE) concentration influenced the properties of the OFs. The stability (phenolic compounds and antioxidant activity) was reduced in the first 20 days, and after this period, it remained constant.

Amphiphilic polyphenol incorporated hydrogel derived from mucoadhesive of Dillenia indica: Potential antioxidant and adsorbent

In this work, the mucoadhesive substances from the fruits and seeds of Dillenia indica (DI), a plant present abundantly in India, have been extracted and utilised to prepare a hydrogel. A synthetically prepared amphiphilic polyphenol (L) has been incorporated within the hydrogel network to enhance the hydrogelation property. Moreover, the DI-L hydrogel's total phenolic content and radical scavenging prospects have been investigated. The DI-L hydrogel has shown good, sensitive, and efficient adsorptive removal of Fe(III) from the aqueous medium with an adsorption capacity of 6.157 mg/g for an initial concentration of 10 mg/L of Fe(III) solution. As a result, these findings elucidate the most innovative application of transforming fruit mucoadhesive into sustainable environmental solutions.

Flavonoid-Loaded Biomaterials in Bone Defect Repair

Skeletons play an important role in the human body, and can form gaps of varying sizes once damaged. Bone defect healing involves a series of complex physiological processes and requires ideal bone defect implants to accelerate bone defect healing. Traditional grafts are often accompanied by issues such as insufficient donors and disease transmission, while some bone defect implants are made of natural and synthetic polymers, which have characteristics such as good porosity, mechanical properties, high drug loading efficiency, biocompatibility and biodegradability. However, their antibacterial, antioxidant, anti-inflammatory and bone repair promoting abilities are limited. Flavonoids are natural compounds with various biological activities, such as antitumor, anti-inflammatory and analgesic. Their good anti-inflammatory, antibacterial and antioxidant activities make them beneficial for the treatment of bone defects. Several researchers have designed different types of flavonoid-loaded polymer implants for bone defects. These implants have good biocompatibility, and they can effectively promote the expression of angiogenesis factors such as VEGF and CD31, promote angiogenesis, regulate signaling pathways such as Wnt, p38, AKT, Erk and increase the levels of osteogenesis-related factors such as Runx-2, OCN, OPN significantly to accelerate the process of bone defect healing. This article reviews the effectiveness and mechanism of biomaterials loaded with flavonoids in the treatment of bone defects. Flavonoid-loaded biomaterials can effectively promote bone defect repair, but we still need to improve the overall performance of flavonoid-loaded bone repair biomaterials to improve the bioavailability of flavonoids and provide more possibilities for bone defect repair.

Comparison of virus-capsid mimicking biologic-shell based versus polymeric-shell nanoparticles for enhanced oral insulin delivery

Virus-capsid mimicking mucus-permeable nanoparticles are promising oral insulin carriers which surmount intestinal mucus barrier. However, the impact of different virus-capsid mimicking structure remains unexplored. In this study, utilizing biotin grafted chitosan as the main skeleton, virus-mimicking nanoparticles endowed with biologic-shell (streptavidin coverage) and polymeric-shell (hyaluronic acid/alginate coating) were designed with insulin as a model drug by self-assembly processes. It was demonstrated that biologic-shell mimicking nanoparticles exhibited a higher intestinal trans-mucus (>80%, 10 min) and transmucosal penetration efficiency (1.6-2.2-fold improvement) than polymeric-shell counterparts. Uptake mechanism studies revealed caveolae-mediated endocytosis was responsible for the absorption of biologic-shell mimicking nanoparticles whereas polymeric-shell mimicking nanoparticles were characterized by clathrin-mediated pathway with anticipated lysosomal insulin digestion. Further, in vivo hypoglycemic study indicated that the improved effect of regulating blood sugar levels was virus-capsid structure dependent out of which biologic-shell mimicking nanoparticles presented the best performance (5.1%). Although the findings of this study are encouraging, much more work is required to meet the standards of clinical translation. Taken together, we highlight the external structural dependence of virus-capsid mimicking nanoparticles on the muco-penetrating and uptake mechanism of enterocytes that in turn affecting their in vivo absorption, which should be pondered when engineering virus-mimicking nanoparticles for oral insulin delivery.

Reviving the interest in the versatile drug nystatin: A multitude of strategies to increase its potential as an effective and safe antifungal agent

Nystatin is an antifungal molecule with a remarkable yet squandered versatility. In this review, its mechanism of action is explored, along with its extensive action spectrum and toxicity. A multitude of methodologies to tackle the drug's physical and chemical hurdles are outlined along with some proven-effective strategies to increase its activity and/or decrease its toxicity. A separate detailed section focused on micro and nanotechnology solutions addresses new drug delivery systems made of polymeric, metallic or lipid materials. Although the topical route depicts greater representativeness amongst these formulations, the intravenous, dental, oral, vaginal and inhalation routes are also mentioned. The unsuccessful previous attempts at developing parenteral formulations of nystatin or even the withdrawal of a nystatin-loaded multilamellar liposome should not divert research away from this drug. In fact, the interest in nystatin ought to be reawakened with the ongoing clinical trials on the promising nystatin-like genetically engineered derivate BSG005.

From Plants to Wound Dressing and Transdermal Delivery of Bioactive Compounds

Transdermal delivery devices and wound dressing materials are constantly improved and upgraded with the aim of enhancing their beneficial effects, biocompatibility, biodegradability, and cost effectiveness. Therefore, researchers in the field have shown an increasing interest in using natural compounds as constituents for such systems. Plants, as an important source of so-called "natural products" with an enormous variety and structural diversity that still exceeds the capacity of present-day sciences to define or even discover them, have been part of medicine since ancient times. However, their benefits are just at the beginning of being fully exploited in modern dermal and transdermal delivery systems. Thus, plant-based primary compounds, with or without biological activity, contained in gums and mucilages, traditionally used as gelling and texturing agents in the food industry, are now being explored as valuable and cost-effective natural components in the biomedical field. Their biodegradability, biocompatibility, and non-toxicity compensate for local availability and compositional variations. Also, secondary metabolites, classified based on their chemical structure, are being intensively investigated for their wide pharmacological and toxicological effects. Their impact on medicine is highlighted in detail through the most recent reported studies. Innovative isolation and purification techniques, new drug delivery devices and systems, and advanced evaluation procedures are presented.

Films composed of white angico gum and chitosan containing chlorhexidine as an antimicrobial agent

Anadenanthera colubrina, popularly known as white angico, is a species extensively cultivated in Brazil, mainly in the cerrado region, including the state of Piauí. This study examines the development of films composed of white angico gum (WAG) and chitosan (CHI) and containing chlorhexidine (CHX), an antimicrobial agent. The solvent casting method was used to prepare films. Different combinations and concentrations of WAG and CHI were used to obtain films with good physicochemical characteristics. Properties such as the in vitro swelling ratio, the disintegration time, folding endurance, and the drug content were determined. The selected formulations were characterised by scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction, and the CHX release time and antimicrobial activity were evaluated. CHX showed a homogenous distribution in all CHI/WAG film formulations. The optimised films showed good physicochemical properties with 80% CHX release over 26 h, which is considered promising for local treatment of severe lesions in the mouth. Cytotoxicity tests of the films did not show toxicity. The antimicrobial and antifungal effects were very effective against the tested microorganisms.

Mucilage polysaccharide as a plant secretion: Potential trends in food and biomedical applications

Current trends are shifting away from using synthetic compounds in favor of discovering new natural component sources that will allow them to create goods that are healthful, environmentally friendly, sustainable, and profitable. The food industry, in light of these trends, has opted to look for safe natural ingredients that will allow the production of low-fat, artificial-additive-free, gluten-free, prebiotic, and fortified foods. Similarly, the pharmaceutical and medical industries have attempted to apply natural ingredients to address the challenges related to biomaterials more efficiently than synthetic ingredients. Against this background, plant mucilage has proven to be a polysaccharide with excellent health features and technological properties, useful for both food and biomedical applications. Many studies have shown that its inclusion in different food matrices improves the quality of the products obtained under appropriate reformulations. At the same time, plant mucilage has been indicated to be a very interesting matrix in biomedical field especially tissue engineering applications since it has been emerged to favor tissue regeneration with its highly biocompatible structure. This concise review discusses the most recent advances of the applications of plant mucilage in different foods as well as its recent use in biomedical field. In this context, firstly, a general definition of mucilage was made and information about plant-based mucilage, which is frequently used, about the plant parts they are found in, their content and how they are obtained are presented. Then, the use of mucilage in the food industry including bakery products, meat emulsions, fermented dairy products, ice cream, and other foods is presented with case studies. Afterwards, the use of plant mucilage in the biomedical field, which has attracted attention in recent years, especially in applications with tissue engineering approach such as scaffolds for tissue regeneration, wound dressings, drug delivery systems and pharmaceutical industry was evaluated.

Fabrication and properties of multi-functional polydopamine coated Cu/F-codoped hydroxyapatite hollow microspheres as drug carriers

Due to its excellent bone conductivity and drug adsorption as well as pH-responsive drug release property, hydroxyapatite (HAp) is widely used as a drug carrier in bone repair field. Here, we report for the first time a novel multi-functional polydopamine (PDA) coated Cu/F-codoped HAp (Cu/F-HAp-PDA) hollow microspheres. Both Cu²⁺ and F^- were successfully doped into the lattice of HAp and uniformly distributed in the shell of hollow microspheres through a one-step hydrothermal synthesis. Then PDA was coated homogeneously on the outer layer of Cu/F-HAp hollow microspheres. Both Cu/F-HAp and Cu/F-HAp-PDA samples displayed high drug loading efficiency and pH responsive drug release behavior. Moreover, the obtained Cu/F-HAp-PDA hollow microspheres exhibited excellent photothermal conversion efficiency and photothermal stability. The molecular dynamics simulations showed that PDA and HAp can form mutual binding mainly through Ca-O bonding, while doxorubicin (DOX) is mainly bound to PDA molecules through hydrogen bonding and π-π stacking interaction.

Biomimetic multifunctional hybrid sponge via enzymatic cross-linking to accelerate infected burn wound healing

Preparing sponge dressings with stable wet adhesion remains difficult in wound repair, especially in burn wounds with bleeding and large amounts of exudate. In this work, a multifunctional hybrid sponge dressing (DHGT+PHMB+TiO₂NPs) with good wet adhesion was developed by combining biomimetic and enzymatic cross-linking reactions. The sponge dressing matrix (DHGT) was prepared by tyrosinase-catalyzed cross-linking of dopamine-modified hyaluronic acid (DOPA-HA) and gelatin. The multifunctional hybrid sponge dressing was obtained by loading polyhexamethylene biguanide (PHMB) and titanium dioxide nanoparticles (TiO₂NPs) onto the DHGT matrix. The newly developed sponge dressing exhibited high mechanical properties, good wet adhesion, antibacterial activity, reactive oxygen species (ROS) scavenging, biocompatibility, and excellent hemostasis ability. In vivo studies showed that the multifunctional hybrid sponge dressing could significantly accelerate the healing of infected full-thickness burn wounds by inhibiting bacterial growth, accelerating skin tissue reepithelialization, collagen deposition, and angiogenesis, as well as regulating the expression of inflammatory factors and cytokines.