查找使用阿拉丁产品的科研文献

Dual Targeting pH-Sensitive Co-Delivery Curcumin and β-Elemene Nanomedicine for Breast Cancer Therapy

Liu Mengna,Wu Jun,Wang Kaili,Yuan Dehao,Wang Yinan,Cheng Haoran,Zhao Feng,Fan Huaying,Xu Hui,Chen Daquan

In this paper, for the sake of improving the bioavailability and tumor targeting ability of curcumin (cur), we reported a nanoplatform self-assembled from Folic acid-Adipic dihydrazide-oligomeric hyaluronic acid (FA-ADH-oHA) as drug carrier, curcumin and β-elemene as loaded model drug for dual targeting to breast cancer cells. We used pH sensitive Folic acid-Adipic dihydrazide (FA-ADH) as hydrophobic moieties, HA as the target of cancer stem cells CD44 receptor. The structure characteristic of this smart multifunctional dual targeting nano-sized carrier was measured by 1H-NMR. Cur, an anticancer drug, was successfully loaded into FA-ADH-oHA micelles by self-assembly with a hydrodynamic diameter of 216.4 ± 0.5 nm. Triggered by faintly acidic tumor microenvironment, more encapsulated curcumin and β-elemene could be released from the FA-ADH-oHA micelles in tumor environment than in the pH 7.3 environment. To sum up, the novel polymeric carrier based on pH sensitive and dual drug-targeting strategies was a prospective delivery platform to enhance therapeutic efficiency and decrease toxic side effect in breast cancer therapy.

Mesoporous carbon/CuS nanocomposites for pH-dependent drug delivery and near-infrared chemo-photothermal therapy

Lei Zhang,Yecheng Li,Zexun Jin,King Ming Chan,Jimmy C. Yu

Spurred by the recent development in nanotechnology, multi-functional therapeutic platforms have emerged as promising anti-cancer treatments for their combinational effects. In this paper, we report a novel drug delivery system composed of mesoporous carbon nanospheres (MCN) of 150 to 200 nm in diameter capped with copper sulfide (CuS) nanoparticles (NPs). MCNs can efficiently load doxorubicin (DOX, an anti-cancer drug) due to their hollow and porous structures as well as the π–π stacking interactions between MCN and DOX. DOX is retained in MCN under a basic and physiological environment, but releases rapidly under an acidic environment in its ionized state. Due to the intrinsic near-infrared (NIR) absorption and photothermal conversion ability of copper sulfide nanoparticles, heat is generated for killing tumor cells as well as stimulating DOX release upon NIR irradiation. Thus, this complex (MCN–CuS) exhibits efficient drug loading, low pre-release, temperature-, NIR- and pH-responsive DOX release, and combined antitumor activity.

Synthesis and evaluation of pH-sensitive, self-assembled chitosan-based nanoparticles as efficient doxorubicin carriers

Mazhar Ali Raja,Muhammad Arif,Chao Feng,Shah Zeenat,Chen-Guang Liu

A novel pH-responsive polymer based on amphiphilic N-acetyl histidine and arginine-grafted chitosan was synthesized using N-acetyl histidine as hydrophobic segment and arginine as hydrophilic segment by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide-mediated coupling reactions as anticancer drug delivery system for doxorubicin. The structure of the synthesized polymer was confirmed by Fourier transform infrared and 1H nuclear magnetic resonance analysis. Due to self-association behavior, N-acetyl histidine and arginine-grafted chitosan structured nanoparticles with in size range of 204 nm. N-acetyl histidine and arginine-grafted chitosan with different substitution degree of N-acetyl histidine were initially prepared and characterized. The critical micelle concentration decreased with increasing substitution degree of N-acetyl histidine. Furthermore, N-acetyl histidine and arginine-grafted chitosan nanoparticles exhibited an acidic pH-triggered aggregation and disassembling nature. The doxorubicin-encapsulated nanoparticles based on synthesized conjugate (N-acetyl histidine and arginine-grafted chitosan/doxorubicin nanoparticles) showed a sustained drug release pattern, which could be hastened under acidic pH conditions but delayed with increasing substitution degree of N-acetyl histidine. Anticancer effects demonstrated that N-acetyl histidine and arginine-grafted chitosan/doxorubicin nanoparticles could suppress both sensitive and resistant human breast tumor cell line (MCF-7) efficiently in a dose- and time-dependent pattern. Confocal microscopy results evidenced increased cellular uptake and enhanced retention of the synthesized nanoparticles in drug-resistant cells demonstrating better efficacy of nanoparticles over native doxorubicin. These results suggest that N-acetyl histidine and arginine-grafted chitosan/doxorubicin nanoparticles might be promising carriers for delivery of hydrophobic drug doxorubicin against drug-resistant tumors.

Benchmarking the pH–Stability Relationship of Metal Oxide Anodes in Anion Exchange Membrane Water Electrolysis

Liyue Zhang,Qiucheng Xu,Yanjie Hu,Ling Chen,Hao Jiang

Anion exchange membrane water electrolysis (AEMWE) is one of the most promising technologies for producing green hydrogen; however, they still suffer from durability issues. One task is to find suitable electrolyte conditions for anode catalysts that endow them with both high activity and stability. Herein, we benchmark the pH–stability relationship of four typical metal oxides as anode catalysts in the AEMWE. Their electrochemical performance and structural stability were in-depth analyzed through impedance, dissolved composition in the electrolyte, and correlated Pourbaix diagram. NiFe2O4 with the best activity and stability in the strong alkaline (pH = 14) shows terrible stability in pure water, which is then verified due to the severe Fe leaching, and it cannot be alleviated by alkaline pre-activation. Notably, Co3O4 shows comparable activity and stability to IrO2 in pure water and weak alkaline conditions. At pH = 12, it entails only ∼2.18 V to reach 1.0 A cm–2 and stabilizes for 40 h, being superior to others. This work screens out suitable transition metal oxides as a substitute for noble metals and their optimal application scenarios for AEMWE.

Chitosan-thymol nanoparticle with pH responsiveness as a potential intelligent botanical fungicide against Botrytis cinerea

Xiaomin Zhao,Yunfei Zhang,Li Chen,Zhiqing Ma,Bin Zhang

The practical application of essential oils (EOs) as an alternative for synthetic pesticides in agricultural production is severely limited because of their instability, high volatility, and water insolubility. Nanoencapsulation of EOs is an important strategy to overcome these limitations. In view of this, this study aimed to develop chitosan-thymol nanoparticle (NCS-Thy) with pH-responsive which can be used as an intelligent botanical fungicide to control Botrytis cinerea . The NCS-Thy nanoparticle was prepared by ionic crosslinking method with the loading capacity and encapsulation efficiency of 29.87% and 41.92%, respectively. The synthesized NCS-Thy nanoparticle was further characterized by Fourier transform infrared spectroscopy analysis, transmission electron microscopy observation, and dynamic lights scattering . The results of release kinetics and antifungal activity of NCS-Thy under different pH conditions were determined. The results showed that the NCS-Thy nanoparticle had excellent pH-responsiveness and can release more thymol under acidic conditions formed by B. cinerea , thereby achieving higher antifungal effects. Therefore, compared with unencapsulated thymol, the NCS-Thy nanoparticle had higher antifungal activity against B. cinerea in vitro . In addition, both the protective and curative efficacies of detached leaf test and pot experiment were significantly higher than those of unencapsulated thymol. Among them, the protective efficacy of NCS-Thy in the pot experiment was 78.73%, which was significantly higher than that of unencapsulated thymol with 61.13%. Therefore, the pH-responsive chitosan-thymol nano-preparation had a promising prospect of application in practical management of gray mold as an intelligent botanical fungicide.

A well-defined thermo- and pH-responsive double hydrophilic graft copolymer bearing pyridine-containing backbone

Rang Chen,Xue Jiang,Guolin Lu,Wenbin Liu,Weize Jin,Guojian Tian,Xiaoyu Huang

Graft copolymers have extensive applications in material science because of the tunable nature of their backbones and side chains and the diverse morphologies of their aggregates. Recent studies have mainly focused on amphiphilic graft copolymers containing hydrophobic backbones and hydrophilic side chains. To the best of our knowledge, no studies have reported amphiphilic graft copolymers bearing pyridine-containing hydrophilic backbones. Based on the design of functional monomers, a new trifunctional acrylate monomer, PyMCIBMA, was prepared in two steps via a Morita–Baylis–Hillman reaction, followed by reaction with 2-chloroisobutyryl chloride. Reversible addition–fragmentation chain transfer (RAFT) polymerization of PyMCIBMA monomer was performed to generate a well-defined poly(PyMCIBMA) homopolymer possessing a Cl-containing ATRP initiating group in each repeat unit. Next, a series of well-defined double hydrophilic graft copolymers bearing densely distributed poly(N-isopropyl acrylamide) (PNIPAM) side chains along the backbone on every unit, PPyMA-g-PNIPAM, was synthesized via atom transfer radical polymerization (ATRP) initiated by poly(PyMCIBMA) homopolymer. The resulting graft copolymers exhibited intriguing dual temperature- and pH-sensitive behavior, signifying their potential applications in controlled delivery as polymer–drug nanocarrier.

pH-Responsive Biomimetic Polymeric Micelles as Lymph Node-Targeting Vaccines for Enhanced Antitumor Immune Responses

Xiqin Yang,Tong Yu,Yingping Zeng,Keke Lian,Xueqing Zhou,Jia Ke,Yinghong Li,Hong Yuan,Fuqiang Hu

Lymph nodes are proposed as the intriguing target in cancer immunotherapy, and cellular immunity is vital for vaccines to fight against cancer. However, inefficient delivery of vaccines to lymph nodes and deficient lysosomal escape of antigens result in weak cellular immunity, which restrains the strength of vaccines in inducing antitumor immune responses. Hence, dendritic cell membrane (DCM)/histidine-modified stearic acid-grafted chitosan (HCtSA)/ovalbumin (OVA) micelles, as pH-responsive biomimetic vaccines, were fabricated to target lymph nodes and induce cellular immunity for enhanced antitumor immune responses. DCM/HCtSA/OVA micelles exhibited pH-dependent antigen release behavior, which resulted in efficient escape of antigens from dendritic cell (DC) lysosomes. Besides, DCM/HCtSA/OVA micelles accumulated and reserved in the lymph nodes, which ensured effective uptake by DCs. Importantly, DCM/HCtSA/OVA micelles induced potent T cell immune responses, promoted secretion of antitumor-related cytokines, and notably inhibited tumor growth. Overall, DCM/HCtSA/OVA micelles exhibit great potential in targeted immunotherapy and can provide guidance for the design of vaccines.

Polymeric micelle-coated mesoporous silica nanoparticle for enhanced fluorescent imaging and pH-responsive drug delivery

Xiubin Xu,Shaoyu Lü,Chunmei Gao,Xinggang Wang,Xiao Bai,Haogang Duan,Nannan Gao,Chen Feng,Mingzhu Liu

Can micelles be served as gating agents and fluorescent labels? Can a drug delivery system be constructed by combining two kinds of drug carriers, such as mesoporous silica nanoparticles and micelles? Will the combination be better or worse? To settle these questions, we designed and constructed a nanocarrier by cooperating two kinds of drug carriers (mesoporous silica nanoparticles and F127 micelles), providing a suitable method for the design of multifunctional stimuli-responsive drug delivery and self-fluorescent imaging systems. The system is fabricated using anticancer drug (curcumin) loaded micelles (CF127) as gating agents and fluorescent labels of mesoporous silica nanoparticles via Schiff base. Because of the pH-sensitive Schiff base, the gating micelles can achieve drug release under acidic condition, while preventing the drug release under natural condition. Moreover, due to the aggregation of CF127 micelles on the surface of mesoporous silica nanoparticles, the fluorescent intensity of CF127 micelles is significantly enhanced. Furthermore, CF127 micelles exhibit good anti-photobleaching property, indicating that the system here is promising for noninvasive in vivo tracking the delivery of therapeutic agents. The cooperation of two kinds of drugs in anti-cancer application and the easily further modification ability of the system is also be confirmed. These results indicate that this study paves the way for a generation of drug delivery systems and could provide a general route to prepare multifunctional biocompatible platforms for biomedical imaging diagnosis and simultaneous therapy for lesion sites such as cancers.

Silk fibroin-based hydrogels as a protective matrix for stabilization of enzymes against pH denaturation

Yueying Han,Sihan Yu,Lichao Liu,Shijia Zhao,Tianxiao Yang,Yajing Yang,Yunming Fang,Shanshan Lv

A significant challenge remains to protect proteins (including enzymes) from inactivation against pH. This study investigated stabilization against pH denaturation of carbonic anhydrase (CA) in silk fibroin (SF)-based hydrogels. CA was immobilized into SF-based hydrogels by a Ru(II) mediated photochemical method, giving rise to ∼100% immobilization efficiency and >60% activity of the free enzyme at the optimum pH value of 8. At an unfavorable acidic pH value of 3, the immobilized CA achieved >20% of the initial activity and ∼8% in the second cycle even after 12 h storage, while the free enzyme lost its activity completely. Fourier transform infrared spectroscopy (FTIR) results suggested that the protective effect of the SF-based hydrogels on the pH stability of CA could be attributed to unique structural feature of the SF molecules, enabling strong intermolecular interactions between SF and CA, and thus increasing protein rigidity against pH denaturation. The same approach was applied to lysozyme and xylanase, and achieved protein stabilization of both enzymes at an unfavorable basic pH value of 9. The SF-based hydrogels demonstrated great potential as a promising matrix for protein immobilization against pH denaturation.

Stretchable Optical Sensing Patch System Integrated Heart Rate, Pulse Oxygen Saturation, and Sweat pH Detection

Guangming Wang,Shaomin Zhang,Shurong Dong,Dong Lou,Lie Ma,Xiachuan Pei,Hongsheng Xu,Umar Farooq,Wei Guo,Jikui Luo

Self-Regulating Neohesperidin/Silk Fibroin Composite Aerogel for Enhanced Wound Healing via pH-Responsive Release

Ziyi Wang,Xu Zhu,Xueting Wang,Zhenhao Shi,Zicheng Zhang,Zijing Wang,Xianchang Xie,Xiaoming Li,Kunpeng Jiang,Hu Liu,Liang Zhou,Dalun Lv

Effective wound healing and tissue regeneration are serious challenges in wound repair. Diseases or external stimuli that affect the body can generate excessive free radicals, which can trigger oxidative stress, inhibit wound healing, and lead to the formation of chronic wounds. Wound healing inhibition can be overcome by regulating the redox balance between reactive oxygen species (ROS) and antioxidants. Neohesperidin (Ne), a plant flavonoid compound with potent antioxidant properties, shows promise in mitigating oxidative stress and supporting wound healing. Here, we developed a novel aerogel dressing (MT-LCA+SF-Ne) by integrating silk fibroin (SF) and Ne into modified cellulose aerogels. The SF-mediated continuous delivery combined with the dual antioxidant/anti-inflammatory effects of Ne results in a sustained-release therapeutic system for wound microenvironment modulation. The aerogel was optimized by tuning its composition, SF concentration, and Ne loading, endowing it with suitable mechanical strength, thermal stability, and biocompatibility, while enabling pH-responsive Ne release aligned with wound healing dynamics. The aerogel disrupted the ROS-inflammation cascade and downregulated the M1/M2 macrophage ratio, thereby enhancing cell proliferation and migration, and demonstrating robust anti-inflammatory and antioxidant properties in vitro. Collectively, this study establishes a bioactive delivery system with pH-tunable release, anti-inflammatory, antioxidant, and tissue-regenerative capabilities and provides new insights into the application of lignocellulosic materials in wound care, holding great potential for clinical translation.

Utilizing Hydrogel-Isolated Dual-Carboxyl Surface-Enhanced Raman Scattering Probe for Accurate Online pH Monitoring

Yan Chen,Zhiyang Zhang,Yanzhou Wu,Ke Liu,Yifan Sui,Xiaotong Su,Jiadong Chen,Jaebum Choo,Lingxin Chen

Surface-enhanced Raman scattering (SERS)-based pH sensors have been widely applied; However, the used 4-mercaptobenzoic acid (4-MBA) probes exhibit small pH-sensitive peak changes (carboxyl group) and strong susceptibility to interference, leading to inaccurate measurements. To address these limitations, we developed a SERS pH sensor using 2,5-dimercaptoterephthalic acid (2,5-DMTA) as the probe, which contains dual carboxyl groups. These carboxyl groups undergo reversible protonation–deprotonation, producing pronounced and reproducible spectral responses that enhance detection accuracy. The developed sensor enabled reliable detection across the acidic pH range of 0–7, showing good linearity (R2 = 0.9786) and compensating for the weak acidic response of 4-MBA. Importantly, the 2,5-DMTA-based pH sensor demonstrated much better detection accuracy (detection relative standard deviation RSD less than 5%) than the 4-MBA-based SERS pH sensor (detection RSD ≈ 20%). To further improve measurement accuracy in complex matrices, the sensor was embedded in hot agarose to form an AuNP@hydrogel substrate, effectively suppressing interference from small molecules. Moreover, the developed sensor also shows satisfactory online pH monitoring features, including good reversibility (≥6 cycles), high stability of continuous measurements (30 min), and long-term storage stability (30 days). Integrated with a microfluidic 3D-printed flow cell, the system enabled rapid response (∼120 s) and online pH monitoring, and was successfully applied to continuous testing in lake water. Overall, this SERS platform provides a robust and accurate solution for SERS-based pH detection under acidic and complex environmental conditions.