Self-Signal-Triggered Drug Delivery System for Tumor Therapy Using Cancer Cell Membrane-Coated Biocompatible Mn3O4 Nanocomposites.

In anti-cancer metastasis treatment, precise drug delivery to cancer cells remains a challenge. Innovative nanocomposites are developed to tackle these issues effectively. The approach involves the creation of manganese oxide (Mn3O4) nanoparticles (NPs) and their functionalization using trisodium citrate to yield functionalized Mn3O4 NPs (F-Mn3O4 NPs), with enhanced water solubility, stability, and biocompatibility. Subsequently, the chemotherapeutic drug doxorubicin (DOX) is encapsulated with Mn3O4 NPs, resulting in DOX/Mn3O4 NPs. To achieve cell-specific targeting, These NPs are coated with HeLa cell membranes (HCM), forming HCM/DOX/Mn3O4. For further refinement, a transferrin (Tf) receptor is integrated with cracked HCM to create Tf-HCM/DOX/Mn3O4 nanocomposites (NC) with specific cell membrane targeting capabilities. The resulting Tf-HCM/DOX/Mn3O4 NC exhibits excellent drug encapsulation efficiency (97.5%) and displays triggered drug release when exposed to NIR laser irradiation in the tumor's environment (pH 5.0 and 6.5). Furthermore, these nanocomposites show resistance to macrophage uptake and demonstrate homotypic cancer cell targeting specificity, even in the presence of other tumor cells. In vitro toxicity tests show that Tf-HCM/DOX/Mn3O4 NC achieves significant anticancer activity against HeLa and BT20 cancer cells, with percentages of 76.46% and 71.36%, respectively. These results indicate the potential of Tf-HCM/DOX/Mn3O4 NC as an effective nanoplatform for chemo-photothermal therapy.

Nutritional awareness of pregnant women and the underlying influencing factors.

Nutritional awareness is described as having knowledge or understanding of nutrition. It is often related to the ability of an individual to make an accurate estimate of their food intake, which involves comparing their actual nutritional behavior with the recommended food consumption. Nutritional awareness of women during the various phases of pregnancy may vary significantly across countries due to cultural and lifestyle differences. There has been extensive research on nutritional awareness of pregnant women in selected countries or regions; however, relatively few studies have explored it during different stages of pregnancy. To fill this gap, this article reviews the existing literature and draws together insights into the following areas: changes in nutritional awareness during various phases of pregnancy, nutritional awareness of pregnant women and its underlying factors in various nations, and the research methods used to study nutritional awareness of pregnant women.

Reduction-Responsive Chitosan-Based Injectable Hydrogels for Enhanced Anticancer Therapy.

Selective delivery of anticancer drug molecules to the tumor site enhances local drug dosages, which leads to the death of cancer cells while simultaneously minimizing the negative effects of chemotherapy on other tissues, thereby improving the patient's quality of life. To address this need, we developed reduction-responsive chitosan-based injectable hydrogels via the inverse electron demand Diels-Alder reaction between tetrazine groups of disulfide-based cross-linkers and norbornene groups of chitosan derivatives, which were applied to the controlled delivery of doxorubicin (DOX). The swelling ratio, gelation time (90-500 s), mechanical strength (G'~350-850 Pa), network morphology, and drug-loading efficiency (≥92%) of developed hydrogels were investigated. The in vitro release studies of the DOX-loaded hydrogels were performed at pH 7.4 and 5.0 with and without DTT (10 mM). The biocompatibility of pure hydrogel and the in vitro anticancer activity of DOX-loaded hydrogels were demonstrated via MTT assay on HEK-293 and HT-29 cancer cell lines, respectively.

Redox-Responsive Comparison of Diselenide and Disulfide Core-Cross-Linked Micelles for Drug Delivery Application.

In this study, diselenide (Se-Se) and disulfide (S-S) redox-responsive core-cross-linked (CCL) micelles were synthesized using poly(ethylene oxide)2k-b-poly(furfuryl methacrylate)1.5k (PEO2k-b-PFMA1.5k), and their redox sensitivity was compared. A single electron transfer-living radical polymerization technique was used to prepare PEO2k-b-PFMA1.5k from FMA monomers and PEO2k-Br initiators. An anti-cancer drug, doxorubicin (DOX), was incorporated into PFMA hydrophobic parts of the polymeric micelles, which were then cross-linked with maleimide cross-linkers, 1,6-bis(maleimide) hexane, dithiobis(maleimido) ethane and diselenobis(maleimido) ethane via Diels-Alder reaction. Under physiological conditions, the structural stability of both S-S and Se-Se CCL micelles was maintained; however, treatments with 10 mM GSH induced redox-responsive de-cross-linking of S-S and Se-Se bonds. In contrast, the S-S bond was intact in the presence of 100 mM H2O2, while the Se-Se bond underwent de-crosslinking upon the treatment. DLS studies revealed that the size and PDI of (PEO2k-b-PFMA1.5k-Se)2 micelles varied more significantly in response to changes in the redox environment than (PEO2k-b-PFMA1.5k-S)2 micelles. In vitro release studies showed that the developed micelles had a lower drug release rate at pH 7.4, whereas a higher release was observed at pH 5.0 (tumor environment). The micelles were non-toxic against HEK-293 normal cells, which revealed that they could be safe for use. Nevertheless, DOX-loaded S-S/Se-Se CCL micelles exhibited potent cytotoxicity against BT-20 cancer cells. Based on these results, the (PEO2k-b-PFMA1.5k-Se)2 micelles can be more sensitive drug carriers than (PEO2k-b-PFMA1.5k-S)2 micelles.

A self-indicating and antibacterial gelatine-chitosan blended hydrogel enabling real-time quality control and sustained bioactive agent delivery.

Hydrogels are one type of materials that are widely exploited for bioactive agent delivery, partly owing to their high biocompatibility and low toxicity. When hydrogels are used as carriers, their performance in agent loading and sustained agent release are predominately determined by the gel structure, which can be largely affected by variations during gel preparation. Till now, effective and easy methods to enable monitoring of such variations in real time have been lacking, making quality control of the generated gel-based carrier technically challenging. To address this technical gap, in this study we take advantage of the clusteroluminogenic properties of gelatine and chitosan to generate a crosslinked blended hydrogel which not only shows intrinsic antibacterial properties and high tunability in delivery performance but also shows a self-indicating capacity to enable quality control during hydrogel preparation. Upon fitting the curves of agent release into different kinetic models, the release profiles of the agent-loaded gels have been found to follow the Higuchi model well, with the non-Fickian mechanism being the major mechanism of the release process. Along with their high efficiency in agent loading, our gels warrant further exploitation for use in bioactive agent delivery and related biomedical applications.

Cross-linked chitosan/lysozyme hydrogels with inherent antibacterial activity and tuneable drug release properties for cutaneous drug administration.

Gels with high drug release sustainability and intrinsic antibacterial properties are of high practical potential for cutaneous drug administration, particularly for wound care and skin disease treatment. This study reports the generation and characterization of gels formed by 1,5-pentanedial-mediated crosslinking between chitosan and lysozyme for cutaneous drug delivery. Structures of the gels are characterized by using scanning electron microscopy, X-ray diffractometry and Fourier-transform infrared spectroscopy. An increase in the mass percentage of lysozyme leads to an increase in the swelling ratio and erosion susceptibility of the resulting gels. The drug delivery performance of the gels can be changed simply by manipulating the chitosan/lysozyme mass-to-mass ratio, with an increase in the mass percentage of lysozyme leading to a decline in the encapsulation efficiency and drug release sustainability of the gels. Not only do all gels tested in this study show negligible toxicity in NIH/3T3 fibroblasts, they also demonstrate intrinsic antibacterial effects against both Gram-negative and Gram-positive bacteria, with the magnitude of the effect being positively related to the mass percentage of lysozyme. All these warrant the gels to be further developed as intrinsically antibacterial carriers for cutaneous drug administration.

Roles and Mechanisms of Astragaloside IV in Combating Neuronal Aging.

Aging can lead to changes in the cellular milieu of the brain. These changes may exacerbate, resulting in pathological phenomena (including impaired bioenergetics, aberrant neurotransmission, compromised resilience and neuroplasticity, mitochondrial dysfunction, and the generation of free radicals) and the onset of neurodegenerative diseases. Furthermore, alterations in the energy-sensing pathways can accelerate neuronal aging but the exact mechanism of neural aging is still elusive. In recent decades, the use of plant-derived compounds, including astragaloside IV, to treat neuronal aging and its associated diseases has been extensively investigated. This article presents the current understanding of the roles and mechanisms of astragaloside IV in combating neuronal aging. The ability of the agent to suppress oxidative stress, to attenuate inflammatory responses and to maintain mitochondrial integrity will be discussed. Important challenges to be tacked for further development of astragaloside IV-based pharmacophores will be highlighted for future research.

ROS-Generating Poly(Ethylene Glycol)-Conjugated Fe3O4 Nanoparticles as Cancer-Targeting Sustained Release Carrier of Doxorubicin.

Purpose: Site-specific drug delivery systems can contribute to the development and execution of effective cancer treatment. Due to its favorable features (including high biocompatibility, high hydrophilicity and ease of functionalization), poly(ethylene glycol) (PEG) has been widely adopted to design drug carriers. Generating carriers for delivery of hydrophobic anticancer agents, however, is still a challenge in carrier design. Methods: In the first step, PEG is functionalized with dialdehyde to generate PEG-(CHO)2 using EDC/NHS chemistry. In the second step, Fe3O4 nanoparticles are functionalized with amino groups to generate Fe3O4-NH2. In the third step, PEG-(CHO)2, Fe3O4-NH2 and doxorubicin (DOX) react in an acidic environment to yield a drug conjugate (PEGDA-MN-DOX), which is subsequently characterized by FT-IR, 1H-NMR, SEM, TEM, DLS, TGA, and DSC. Results: The chemical functionalities of the drug conjugate are confirmed by FTIR, H-NMRand XRD analysis.The release pattern of PEGDA-MN-DOX is investigated at 25 and 37 °C at different pH values. The results indicate that the developed drug conjugate cannot only behave as a sustained-release carrier, but can also generate a significant level of reactive oxygen species (ROS), leading to a high level of toxicity against MCF-7 cells while still showing excellent biocompatibility in 3T3 cells. Conclusion: The reported conjugate shows anticancer potential, cancer-targeting ability, and ROS-generating capacity for effective drug encapsulation and sustained release in chemotherapy.

Advances in the Analysis of Pharmaceuticals by Using Graphene-Based Sensors.

Safe and effective use of drugs relies on proper pharmaceutical analysis. Graphene has been extensively used to construct sensors for this purpose. Over the years, a large variety of pharmaceutical sensors have been developed from graphene or its derivatives. This article reviews the current status of sensor development from graphene and its derivatives, and discusses the use of graphene-based sensors in pharmaceutical analysis. It is hoped that this article offers not only a snapshot of recent advances in the fabrication and use of graphene-based sensors, but also provides insights into future engineering and optimization of the sensors for effective pharmaceutical analysis.

Development of a composite film fabricated from carboxymethyl chitosan and magnetite nanoparticles for pH-responsive bioactive agent release.

Development of a biocompatible film enabling stimuli-responsive bioactive agent delivery has a high practical value for food and pharmaceutical applications. In this study, we generate a composite film, using the solution casting approach, from carboxymethyl chitosan (CMC) and magnetite nanoparticles (MNPs). The structures and properties of CMC, MNPs, and the generated film are characterized by using various characterization techniques, including Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, x-ray diffraction spectroscopy, and scanning electron microscopy. With the use of doxorubicin (DOX) as a model agent, the percentage of cumulative release of DOX from the agent-loaded film is found to be increased from 55% to 62% when the pH of the surrounding medium changes from 7.4 to 5.0. Our film warrants further development and optimization as a carrier to mediate pH-responsive bioactive agent release.