Role of tea polyphenols in enhancing the performance, sustainability, and catalytic cleaning capability of membrane separation for water-soluble pollutant removal.

Tea polyphenols (TPs), like green tea polyphenol (GTP) and black tea polyphenol (BTP), with phenolic hydroxyl structures, form coordination and hydrogen bonds, making them effective for bridging inorganic catalysts and membranes. Here, TPs were employed as interface agents for the preparation of TPs-modified needle-clustered NiCo-layered double hydroxide/graphene oxide membranes (NiCo-LDH-TPs/GO). The incorporation of porous guest material, NiCo-LDH-TPs, facilitated water channel expansion, enhancing membrane permeability and resulting in the development of high-performance, sustainable catalytic cleaning membranes. The introduction of TPs through coordination weakened the surface electronegativity of NiCo-LDH, promoting a uniform mixed dispersion with GO and facilitating membrane self-assembly. NiCo-LDH-GTP/GO-5 and NiCo-LDH-BTP/GO-5 membranes demonstrated permeances of 85.98 and 90.76 L m-2 h-1 bar-1, respectively, with rejections of 98.73% and 99.54% for methylene blue (MB). Notably, the NiCo-LDH-BTP/GO-5 membrane maintained a high rejection of 97.11% even after 18 cycles in the catalytic cleaning process. Furthermore, the modification of GTP and BTP enhanced MB degradation through PMS activation, resulting in a 0.33% and 0.35% increase in the reaction rate constants of NiCo-LDH, respectively, while reducing metal ion spillover. These findings highlighted the potential of TPs in enhancing the efficiency and sustainability of catalytic cleaning GO membranes for water purification and separation processes.

A Bio-Inspired Free-Standing Film with Versatility: From Heterogeneous CTCs Programed Isolating to Breast Cancer Molecular Typing.

Developing a robust strategy for profiling heterogeneous circular tumor cells specifically, distinguishing the phenotypes of which in blood sample of cancer patient precisely, and releasing them sequentially, is significant for cancer management by liquid biopsy. Herein, a bio-inspired free-standing and flexible film composed of TiO2 nanotube and silk fibroin, fabricated with multiply dynamic bioactive surface (TSF/MDBS) by a simple and eco-friendly way including using polydopamine chemistry and dual dynamic covalent chemistry, is reported. The as-prepared TSF/MDBS binds specific peptides toward cells with epithelial biomarker and human epithelial growth factor receptor 2 (HER2) biomarker, and antifouling agents bovine serum albumin for obviating platelets and proteins adhering of blood, can capture heterogeneous CTCs with enhanced capability due to the cytocompatible soft film and exquisite surface design, and further release the captured cells as program, by specifically breaking down the covalent bonds in sequence via the action of adding biocompatible molecules fructose and glutathione. By applying the TSF/MDBS, it can be tailored into desired pieces for identifying CTCs with different phenotypes (HER2-high and HER2-low) from the unprocessed blood samples of breast cancer patients, and finally profiling these heterogeneous CTCs, to discriminate HER2 positive or negative of breast cancer patients in clinical applications.

Versatile Dynamic Bioactive Lubricant-Infused Surface for Effective Isolation of Circulating Tumor Cells.

The rarity of circulating tumor cells (CTCs) and the complexity of blood components present major challenges for the efficient isolation of CTCs in blood. The coexisting matters could interfere with the detection of CTCs by adhering to the binding sites on the material surface, leading to the reduced accuracy of biomarker capture in blood. Herein, we developed dynamic bioactive lubricant-infused slippery surfaces by grafting the 1H,1H,2H,2H-heptadecafluorodecyl acrylate polymer and 3-acrylamidophenylboronic acid polymer brushes on quartz plates by UV light-initiated and then grafted cancer cell-binding peptides via reversible catechol-boronate chemistry between phenylboronic acid groups and 3,4-dihydroxy-l-phenylalanine groups of peptides for high-efficient capture of CTCs and nondestructive release of the desired cells in sugar response. Patterned dynamic bioactive lubricant-infused surfaces (PDBLISs) further exhibited the improved capture efficiency of CTCs and more effective antifouling properties for nonspecific cells and blood components. Moreover, the PDBLIS can efficiently capture rare cancer cells from the mimic of cancer patient's blood samples. We anticipate that the strategy we proposed would be used in further clinical diagnosis of complicated biofluids related to a variety of tumors and exhibit good prospects and potential in future liquid biopsies.

A Dual-Responsive Peptide-Based Smart Biointerface with Biomimetic Adhesive Behaviors for Bacterial Isolation.

As mimics of the extracellular matrix, surfaces with the capability of capturing and releasing specific cells in a smart and controllable way play an important role in bacterial isolation. In this work, we fabricated a dual-responsive smart biointerface via peptide self-assembly and reversible covalent chemistry biomimetic adhesion behavior for bacterial isolation. Compared with that of the biointerface based on a single reversible covalent bond, the bacterial enrichment efficiency obtained in this work was 2.3 times higher. Furthermore, the release of bacteria from the surface could be achieved by dual responsiveness (sugar and enzyme), which makes the biointerface more adaptable and compatible under different conditions. Finally, the reusability of the biointerface was verified via peptide self-assembly and the regenerated smart biointerface still showed good bacterial capture stability and excellent release efficiency, which was highly anticipated to be more widely applied in biomaterial science and biomedicine in the future.

A versatile pH-responsive peptide based dynamic biointerface for tracking bacteria killing and infection resistance.

Herein we reported a versatile dynamic biointerface based on pH-responsive peptide self-assembly and disassembly to capture the bacteria to avoid bacteria further infected tissue around that can release peptides from the surface in a slightly acidic environment to kill the bacteria with the specificity. The exposed biointerface still presented infection resistance.

Thermo-responsive imprinted hydrogel with switchable sialic acid recognition for selective cancer cell isolation from blood.

In this work, a sialic acid (SA)-imprinted thermo-responsive hydrogel layer was prepared for selective capture and release of cancer cells. The SA-imprinting process was performed at 37 °C using thermo-responsive functional monomer, thus generating switchable SA-recognition sites with potent SA binding at 37 °C and weak binding at a lower temperature (e.g., 25 °C). Since SA is often overexpressed at the glycan terminals of cell membrane proteins or lipids, the SA-imprinted hydrogel layer could be used for selective cancer cell recognition. Our results confirmed that the hydrogel layer could efficiently capture cancer cells from not only the culture medium but also the real blood samples. In addition, the captured cells could be non-invasively released by lowing the temperature. Considering the non-invasive processing mode, considerable capture efficiency, good cell selectivity, as well as the more stable and durable SA-imprinted sites compared to natural antibodies or receptors, this thermo-responsive hydrogel layer could be used as a promising and general platform for cell-based cancer diagnosis.

Bioclickable and mussel adhesive peptide mimics for engineering vascular stent surfaces.

Thrombogenic reaction, aggressive smooth muscle cell (SMC) proliferation, and sluggish endothelial cell (EC) migration onto bioinert metal vascular stents make poststenting reendothelialization a dilemma. Here, we report an easy to perform, biomimetic surface engineering strategy for multiple functionalization of metal vascular stents. We first design and graft a clickable mussel-inspired peptide onto the stent surface via mussel-inspired adhesion. Then, two vasoactive moieties [i.e., the nitric-oxide (NO)-generating organoselenium (SeCA) and the endothelial progenitor cell (EPC)-targeting peptide (TPS)] are clicked onto the grafted surfaces via bioorthogonal conjugation. We optimize the blood and vascular cell compatibilities of the grafted surfaces through changing the SeCA/TPS feeding ratios. At the optimal ratio of 2:2, the surface-engineered stents demonstrate superior inhibition of thrombosis and SMC migration and proliferation, promotion of EPC recruitment, adhesion, and proliferation, as well as prevention of in-stent restenosis (ISR). Overall, our biomimetic surface engineering strategy represents a promising solution to address clinical complications of cardiovascular stents and other blood-contacting metal materials.

Robust Nacrelike Graphene Oxide-Calcium Carbonate Hybrid Mesh with Underwater Superoleophobic Property for Highly Efficient Oil/Water Separation.

Inspired by the mastoid structure of the lotus leaf and the robust layered structure of the nacre, a novel nacrelike graphene oxide-calcium carbonate (GO-CaCO3) hybrid mesh with superhydrophilic and underwater superoleophobic property was prepared for the first time, via a facile, economical, and environmentally friendly layer-by-layer (LBL) self-assembly method using commercially available stainless steel mesh (SSM) as a ready-made mask. Interestingly, GO nanosheets played a threefold role, regulating the growth of CaCO3 nanocrystals between the GO interlamination for constructing a "brick-and-mortar" structure, improving the interface stability via coordination assembly onto SSM, and creating strong hydration derived from rich oxygen-containing functional groups. The surface hydrophilicity and hierarchically micro/nanoscale structure of GO-CaCO3 artificial pearls imbed on the SSM, contributing to outstanding superhydrophilicity and underwater superoleophobicity. The biomimetic hybrid mesh exhibited a strong mechanical property with a Young's modulus of 25.4 ± 2.6 GPa. The optimized hybrid mesh showed a high separation efficiency of more than 99% toward a series of oil/water mixtures with high flux. The low oil-adhesion force, high fatigue-resistance, chemical stability (acid/alkali/salt resistance), and excellent recycling performance enlighten the great prospects of GO-based nacrelike material for application in oily wastewater treatment.

A Magnetic Dynamic Microbiointerface with Biofeedback Mechanism for Cancer Cell Capture and Release.

Dynamic biointerfaces with reversible surface bioactivities enable dynamic modulation of cell-material interactions, thus attracting great attention in biomedical science. Herein, we demonstrated a paradigm shift of dynamic biointerfaces from macroscopical substrates to micron-sized particles by reversible engineering of a phenylboronic acid (PBA)-functionalized magnetic microbead with mussel-inspired cancer cell-targeting peptide. Due to reversible catechol-boronate interactions between the peptides and microbeads, the micron-sized dynamic biointerface exhibited sugar-responsive cancer-targeting activity, showing the potential as a microplatform for magnetic and noninvasive isolation of cancer cells through natural biofeedback mechanism (e.g., human glycemic volatility). Our results demonstrated that the dynamic magnetic platform was capable of selective cancer cell capture (∼85%) and sugar-triggered release of them (>93%) in cell culture medium with high efficiency. More importantly, by using this platform, a decent number of target cells (∼23 on average) could be magnetically isolated and identified from artificial CTC blood samples (1 mL) spiked with 100 cancer cells. In view of the biomimetic nature, high capture efficiency, excellent selectivity, and superiority in cell separation and purification processes, the dynamic magnetic microplatform reported here would be a promising and general tool for rare cell detection and separation and cell-based disease diagnosis.

Mussel-Derived, Cancer-Targeting Peptide as pH-Sensitive Prodrug Nanocarrier.

In this work, we prepared a novel cancer chemotherapeutic nanocarrier through the self-assembly of a mussel-derived, cancer-targeting peptide with a pH-sensitive conjugation of antitumor drugs. The biomimetic peptide was designed with a fluorescent molecule fluorescein isothiocyanate for imaging, a RGD sequence for cancer-targeting and tetravalent catechol groups for dynamic conjugation of the antitumor drug bortezomib via pH-cleavable boronic acid-catechol esters. Our study demonstrated that the peptide-based prodrug nanocarrier dramatically the enhanced specific cellular uptake and cytotoxicity toward human breast cancer cells in vitro in comparison with free drug and nontargeting control nanoparticles. Likewise, the prodrug nanocarrier showed improved therapeutic efficacy and low systematic toxicity in vivo. Considering highly biomimetic nature of the peptide-based nanocarriers, rapid drug release from the dynamically conjugated prodrugs, and convenience of introducing cancer-targeting activity onto this nanosystem, we believe our work would provide new ideas for the development of intelligent and biocompatible drug delivery systems to improve the chemotherapy efficacy in clinic. Furthermore, the pH-sensitive drug conjugation mechanism on peptide-based nanocarriers would provide a hint for the exploitation of dynamic prodrug strategies and the development of highly biocompatible nanocarriers using biogenic materials, e.g., the proteinogenic nanomaterials decorated with drugs through dynamic covalent chemistry.

Dynamic Synthetic Biointerfaces: From Reversible Chemical Interactions to Tunable Biological Effects.

Dynamic synthetic biointerface is a new concept of biomaterials with smart surface properties capable of controlled display of bioactive ligands, dynamic modulation of cell-biomaterial interactions, and subsequently clever manipulation of fundamental cell behaviors like adhesion, migration, proliferation, differentiation, apoptosis, and so on. As mimics of the extracellular matrix (ECM), such molecularly dynamic biointerfaces have attracted increasing attention because of their tunable biological effects with great significance in in situ cell biology, tissue engineering, drug targeting, and cell isolation for cancer theranostics. Approaches to control bioligand presentation on materials mainly rely on surface functionalization with dynamic or reversible chemical linkers to which the ligands are tethered. Photoelectric-transformable or photocleavable chemistry, host-guest supramolecular chemistry, and multiple noncovalent interactions were initially employed for fabrication of dynamic synthetic biointerfaces. However, the external stimuli required in these systems, including electrochemical potential, electrochemical reaction, and near-infrared or UV light, are mostly invasive to living cells; and few of them are able to respond to the stimuli occurring in natural biological processes. In addition, most of current systems focused only on the control of cell adhesion, other cell behaviors like migration, differentiation and apoptosis have rarely been explored. Therefore, the development of novel synthetic biointerfaces that permit access to noninvasive control of diverse cell behaviors still represents a key challenge in biomaterials science. Our group pioneers the use of reversible covalent bonds, metal coordinative interactions, and the molecular affinity of molecularly imprinted synthetic receptors as the dynamic driving forces for the fabrication of smart biointerfaces. Several typical biological stimuli, such as glycemic volatility, body temperature fluctuations, regional disparity of pH values, and specific biomolecules, were tactfully involved in our systems. In this Account, we highlight the strategies we have used on the exploitation of dynamic synthetic biointerfaces based on the above three types of reversible chemical interactions. While our attention has been focused on biologically stimuli-responsive or other noninvasive ligand presentation, the versatility of dynamic synthetic biointerfaces in control of cell adhesion, directing cell differentiation, and targeting cell apoptosis has also been successfully demonstrated. In addition, a paradigm shift of dynamic synthetic biointerfaces from macroscopic to microscopic scale (e.g., nanobiointerfaces) was conceptually demonstrated in our research. The potential applications of these developed dynamic systems, including fundamental cell biology, surface engineering of biomaterials, scaffold-free tissue engineering, cell-based cancer diagnosis, and drug targeting cancer therapy, were also introduced, respectively. Although the development of dynamic synthetic biointerfaces is still in its infancy, we strongly believe that further efforts in this field will play a continuously and increasingly significant role in bridging the gap between chemistry and biology.

Curcumin Induces Autophagy via Inhibition of Yes-Associated Protein (YAP) in Human Colon Cancer Cells.

BACKGROUND Colon cancer is one of the most common cancers and it is the fourth leading cause of cancer-related deaths worldwide. YAP can promote cell proliferation and inhibit apoptosis, leading to loss of cell contact inhibition and promoting malignant cell transformation. MATERIAL AND METHODS In this study we analyzed the effects of different curcumin concentrations on the proliferation of colon cancer cells using MTT and colony formation assays. Western blot detection was performed to confirm the YAP, LC3-II, and P62 expression. RESULTS Curcumin inhibited proliferation and promoted colon cancer cell autophagy. In addition, Western blot results indicated that curcumin suppressed YAP expression in colon cancer cells. To assess the mechanism, we treated the cell lines with curcumin and assessed YAP overexpression and YAP knockdown. The results revealed that curcumin inhibits the proliferation and promotes autophagy of these cell lines. Western blot results showed that curcumin reversed the effect of YAP in colon cancer cells. CONCLUSIONS Our results suggest that YAP has great promise for treatment of colon cancer and that it might be a potential diagnostic marker for colon cancer.

A Versatile Dynamic Mussel-Inspired Biointerface: From Specific Cell Behavior Modulation to Selective Cell Isolation.

Reported here is a novel dynamic biointerface based on reversible catechol-boronate chemistry. Biomimetically designed peptides with a catechol-containing sequence and a cell-binding sequence at each end were initially obtained. The mussel-inspired peptides were then reversibly bound to a phenylboronic acid (PBA) containing polymer-grafted substrate through sugar-responsive catechol-boronate interactions. The resultant biointerface is thus capable of dynamic presentation of the bioactivity (i.e. the cell-binding sequence) by virtue of changing sugar concentrations in the system (similar to human glycemic volatility). In addition, the sugar-responsive biointerface enables not only dynamic modulation of stem cell adhesion behaviors but also selective isolation of tumor cells. Considering the highly biomimetic nature and biological stimuli-responsiveness, this mussel-inspired dynamic biointerface holds great promise in both fundamental cell biology research and advanced medical applications.

A promoter that drives gene expression preferentially in male transgenic rats.

Gender-preferential gene expression is a widespread phenomenon in humans. It is important to study how gender differences influence the pathogenesis of various diseases and response to specific drugs. The aim of this study is to determine if the mouse albumin enhancer/promoter may serve as the promoter to introduce gender-preferential gene expression in transgenic animals. We created four independent transgenic rat lines in which the human C-reactive protein transgene was under the control of mouse albumin enhancer/promoter. Quantitative real time RT-PCR analysis showed that transgene expression in the liver of male rats was significantly higher than transgene expression in the female rats (P < 0.05).There was a 5.3-fold (male/female) difference in line-519, and a 12.2-fold (male/female) difference in line-488. Enzyme-linked immunosorbent assay showed that the serum of male transgenic rats had a 13- to 679-fold difference at the protein level on transgene production compared with female transgenic rats. The male-to-female difference in gene expression was 10- to 17-fold in the liver of transgenic rats. Orchiectomy dramatically reduced protein production from the transgene in the liver. Testosterone administration into female rats did not increase the transgene expression, but estrogen administration into the male rats reduced transgene expression. This study provides a valuable tool for investigating the pathological roles of genes that are expressed in a gender-preferential manner in human disease.