Recombinant Collagen-Templated Biomineralized Synthesis of Biocompatible pH-Responsive Porous Calcium Carbonate Nanospheres.

The synthesis of calcium carbonate with controlled morphology is crucial for its biomedical applications. In this study, we synthesized well-ordered porous calcium carbonate nanospheres using recombinant collagen as a biomineralization template. Porous collagen-calcium carbonate was created by incubating calcium chloride and sodium carbonate with collagen biotemplates at room temperature. Our results show that the recombinant collagen-calcium carbonate nanomaterials underwent a morphological transition from solid nanospheres to more porous nanospheres and a phase transformation from vaterite to a mixture of calcite and vaterite. This study highlights the crucial role of recombinant collagen in modulating the morphology and crystallinity of calcium carbonate nanoparticles. Importantly, the highly porous recombinant collagen-calcium carbonate hybrid nanospheres demonstrated superior loading efficacy for the model drug cefoperazone. Furthermore, the drug loading and releasing results suggest that hybrid nanospheres have the potential to be robust and biocompatible pH-responsive drug carriers. Our findings suggest that recombinant collagen's unique amino acid content and rodlike structure make it a superior template for biomineralized synthesis. This study provides a promising avenue for the production of novel organic-inorganic nanostructures, with potential applications in biomedical fields such as drug delivery.

Fisetin's Promising Antitumor Effects: Uncovering Mechanisms and Targeting for Future Therapies.

Background Cancer remains a critical global health challenge and a leading cause of mortality. Flavonoids found in fruits and vegetables have gained attention for their potential anti-cancer properties. Fisetin, abundantly present in strawberries, apples, onions, and other plant sources, has emerged as a promising candidate for cancer prevention. Epidemiological studies linking a diet rich in these foods to lower cancer risk have sparked extensive research on fisetin's efficacy. Objective This review aims to comprehensively explore the molecular mechanisms of fisetin's anticancer properties and investigate its potential synergistic effects with other anticancer drugs. Furthermore, the review examines the therapeutic and preventive effects of fisetin against various cancers. Methods A systematic analysis of the available scientific literature was conducted, including research articles, clinical trials, and review papers related to fisetin's anticancer properties. Reputable databases were searched, and selected studies were critically evaluated to extract essential information on fisetin's mechanisms of action and its interactions with other anticancer drugs. Results Preclinical trials have demonstrated that fisetin inhibits cancer cell growth through mechanisms such as cell cycle alteration, induction of apoptosis, and activation of the autophagy signaling pathway. Additionally, fisetin reduces reactive oxygen species levels, contributing to its overall anticancer potential. Investigation of its synergistic effects with other anticancer drugs suggests potential for combination therapies. Conclusion Fisetin, a bioactive flavonoid abundant in fruits and vegetables, exhibits promising anticancer properties through multiple mechanisms of action. Preclinical trials provide a foundation for further exploration in human clinical trials. Understanding fisetin's molecular mechanisms is vital for developing novel, safe, and effective cancer prevention and treatment strategies. The potential synergy with other anticancer drugs opens new avenues for combination therapies, enhancing cancer management approaches and global health outcomes.

A review on optical sensors based on layered double hydroxides nanoplatforms.

In recent years, significant efforts have been devoted towards the fabrication and application of layered double hydroxides (LDHs) due to their tremendous features such as excellent biocompatibility with negligible toxicity, large surface area, high conductivity, excellent solubility, and ion exchange properties. Most impressive, LDHs offer a favorable environment to attach several substances such as quantum dots, fluorescein dyes, proteins, and enzymes, which leads to strengthening the catalytic properties or increasing the sensing selectivity and sensitivity of the resulted hybrids. With the extensive ongoing research on the application of nanomaterials, many studies have led to remarkable achievements in exploring LDHs as sensing nanoplatforms. In optical sensors, for instance, many sensing strategies were tailored based on the enzyme-mimicking properties of LDHs, including colorimetric and chemiluminescence procedures. Meanwhile, others were designed based on intercalating some fluorogenic substrates on the LDHs, whereby the sensing signal can be acquired by quenching or enhancing their fluorescence after the addition of analytes. In this review, we aim to summarize the recent advances in optical sensors that use layered double hydroxides as sensing platforms for the determination of various analytes. By outlining some representative examples, we accentuate the change of spectral absorbance, chemiluminescence, and photoluminescence phenomena triggered by the interaction of LDH or functionalized-LDH with the indicators and analytes in the system. And finally, current limitations and possible future orientation in designing further LDHs-based optical sensors are presented. It is hoped that this review will be helpful in assisting the establishment of more improved sensors based on LDHs features. Optical sensors based on layered double hydroxides (LDHs) nanoplatforms were reviewed. The sensing system and detection approaches were rationally reviewed. Possible future orientations were highlighted.

Deep eutectic solvents-assisted synthesis of ZnCo2O4 nanosheets as peroxidase-like nanozyme and its application in colorimetric logic gate.

Pyrophosphate (PPi) and pyrophosphatase (PPase) play a significant role in the therapy of arthritic and clinical diagnosis. In this study, we quickly synthesized ZnCo2O4 nanosheets (NSs) with excellent peroxidase catalytic activity in basic deep eutectic solvent (DES). It was found that PPi could inhibit the catalytic capability of ZnCo2O4 NSs transforming colorless o-phenylenediamine (OPD) into yellow oxidized OPD (oxOPD), and the absorbance falls down at 420 nm. However, if PPase was simultaneously present in the system, PPi would be hydrolyzed, leading to the restoration of peroxidase activity of ZnCo2O4 NSs. Therefore, paving a way for colorimetric analysis of PPi as well as PPase. Furthermore, on the basis of above colorimetric assay, an IMPLICATION logic gate was legitimately designed. With the advantages of fast-speed, low-cost and simplification, we firmly believe that our proposed system has a good potential for simple and fast clinic diagnosis of arthritic diseases, even has great significance in the fields of life sciences, environmental measurement and food safety.

Deep eutectic solvent-assisted facile synthesis of copper hydroxide nitrate nanosheets as recyclable enzyme-mimicking colorimetric sensor of biothiols.

In the quest for alternative products that would conquer natural enzyme drawbacks, enzyme-like nanomaterials with controllable morphology, high catalytic activity, excellent stability, and reusability have gained extensive attention in recent years. Herein, a simple and versatile strategy based on basic deep eutectic solvents was used to create layered copper hydroxide nitrate (Cu2(OH)3NO3) with a well-structured nanosheet-like morphology. The present nanosheets exhibited extraordinary oxidase and peroxidase-like activity. More importantly, these nanosheets have shown the ability to operate at low and high temperatures with appreciable stability and multiple reusabilities. Based on inhibiting the oxidase-like activity of the prepared Cu2(OH)3NO3, we designed a colorimetric sensing technique with a high-efficiency detection of biothiols in serum samples. Because of the simplicity and low-cost fabrication approach, our findings would be beneficial to the artificial enzyme research community as another facile and green tactics to fabricate heterogeneous artificial enzymes. Graphical abstract.

Cadmium cobaltite nanosheets synthesized in basic deep eutectic solvents with oxidase-like, peroxidase-like, and catalase-like activities and application in the colorimetric assay of glucose.

Cadmium cobaltite (CdCo2O4) nanosheets were ultra-fast synthesized based on a new basic deep eutectic solvent (DES) which served simultaneously as reactant, solvents, and template. Interestingly, the nanosheets were found to exhibit triple-enzyme mimetic activities including oxidase-like activity, peroxidase-like activity, and catalase-like activity. Their catalytic activity followed the typical Michaelis-Menten kinetics, and high affinity for H2O2 and TMB was observed. Based on the superior peroxidase-like catalytic activity of CdCo2O4 nanosheets, a highly sensitive and selective colorimetric strategy for the determination of glucose was established. Under optimized conditions, the absorbance at 652 nm increases linearly in the 0.5 to 100 µM concentration range, and the limit of detection is 0.13 µM (S/N = 3). Finally, the method was successfully used for determination of glucose in serum samples. Graphical abstract The CdCo2O4 nanosheets were ultra-fast synthesized with a basic deep eutectic solvent, and this nanomaterial exhibited triple-enzyme mimetic activities: oxidase-like activity, peroxidase-like activity, and catalase-like activity. Based on the peroxidase-like activity, a highly sensitive and selective glucose colorimetric sensor was established.

Synthesis of manganese phosphate hybrid nanoflowers by collagen-templated biomineralization.

Construction of protein-inorganic hybrid materials with hierarchical nanostructures is critical for the creation of advanced multi-functional materials. We herein for the first time report the synthesis of protein-manganese phosphate hybrid nanomaterials by environmentally amiable biomineralization approach. We have demonstrated that collagen provides an excellent biotemplate to modulate the morphology of the hybrid materials, leading to exquisite nanoflowers with branched petals. In this time-dependent biomineralization process, collagen played an essential role in the production of protein-manganese phosphate hybrid materials by inducing the nucleation of manganese phosphates to form a scaffold as well as serving as a glue to hold the petals together. The as-prepared CL-Mn3(PO4)2 nanoflowers exhibited good catalytic activity towards water oxidation. The unique (Gly-X-Y) n amino acid sequences and triple helix structure may provide extraordinary capability for collagen to create hybrid nanomaterials via collagen-templated biomineralization. The single-size and high purity may endow recombinant collagen as a powerful strategy to establish superior biotemplates. This facile and green approach to produce collagen-manganese phosphate hybrid nanoflowers greatly advances our capability to construct manganese phosphates-based functional materials.

Tuning the hierarchical nanostructure of hematite mesocrystals via collagen-templated biomineralization.

The synthesis of hematite mesocrystals with a tunable hierarchical nanostructure plays a critical role in the construction of improved functional materials. We have demonstrated that two recombinant collagen proteins can be used as superior biotemplates to produce hematite mesocrystals with easily tunable hierarchical nanostructures under hydrothermal conditions. Compared with previously reported proteins, collagen is able to regulate the hierarchical structures of hematite mesocrystals with a much lower concentration, and collagen can produce a richer diversity of hierarchical nanostructures, adding two novel diamond-like and sphere-like structures in addition to the three previously reported structures (spindle-like, olive-like, and ellipsoidal-like). The distinct (Gly-X-Y)n amino acid sequence pattern and triple helix structure may provide unique capability for collagen in protein-templated biomineralization. Our studies have indicated that sequence and structural differences in proteins may lead to a plethora of novel nanostructures, which would significantly contribute to the development of improved inorganic nanomaterials.