查找使用阿拉丁产品的科研文献

Advanced electrochemical impedance immunosensor based on PS-b-PAA film architecture for sensitive alpha-fetoprotein detection

Yongbin Qin,Jun Guan,Dan Xu,Chengyin Wang,Jun Sun,Zichen Zheng,Wei Gu,Kewei Liu,Carla Bittencourt,Lifeng Zhang

Alpha-Fetoprotein (AFP) is an important tumor biomarker closely associated with the early diagnosis of hepatocellular carcinoma and other diseases. To achieve rapid and highly sensitive AFP detection, this study developed a label-free electrochemical impedance immunosensor with enhanced sensitivity based on Polystyrene- block -poly acrylic acid (PS-b-PAA) thin films and a biotin-streptavidin (B-SA) amplification strategy. The sensor utilizes the unique properties of PS-b-PAA thin films, where carboxyl groups (-COOH) form covalent bonds with the amino groups (−NH 2 ) of streptavidin, combined with the B-SA system to achieve efficient antibody immobilization. The results showed that the B-SA system significantly enhanced antibody immobilization efficiency, reduced non-specific adsorption, and improved the sensitivity and specificity of electrochemical signals. As a signal amplification strategy, the biotin-streptavidin system increased the sensing signal by approximately 2.19-fold. The sensor exhibited a linear response range from 0.05 ng/mL to 300.00 ng/mL and a detection limit of 0.02 ng/mL. Moreover, the sensor's performance in real human serum samples was consistent with that of the enzyme-linked immunosorbent assay (ELISA), demonstrating excellent reproducibility and long-term stability. This study shows that the fabricated electrochemical impedance immunosensor, based on PS-b-PAA thin films and the B-SA system, exhibits excellent performance in AFP detection, providing a reliable, rapid, and efficient solution for early cancer biomarker detection.

Preparation of PEI-PAA/PDMC IPN Superhydrophilic Composite Hydrogels and Their Multifunctional Application in Wastewater Treatment

Yuxuan Zhang,Zaosheng Lv,Jiangqin Wu,Qianwen Xue,Yang Lei,Yanfen Huang

Polyacrylic acid has a wide range of applications in the field of superhydrophilicity, but due to its single composition, there are problems such as insufficient mechanical strength and functional limitations. In order to extend its application, we prepared a new IPN hydrogel PEI-PAA/PDMC. The results show that the new hydrogel loaded on different substrates (stainless steel mesh/filter cloth) possesses superhydrophilicity (WCA < 10°) and underwater superoleophobicity (OCA > 150°). The hydrogels not only separated oil–water mixtures with high throughput and efficiency (98%, 12,000 L m −2 h −1 ), but also separated oil-in-water emulsions by gravity alone (95%, 700 L m −2 h −1 ). Due to the large number of quaternary ammonium groups in the DMC, we have tested the antimicrobial properties of the DMC with excellent results (99.2% inhibition). Compared with previous studies, this paper introduces that PEI has the ability to adsorb heavy metals, and we tested Cu 2+ and found that the adsorption and separation efficiency reached 75%. This study provides new ideas for the direction of wastewater treatment.

Reduction-degradable PEG-b–PAA-b–PEG triblock copolymer micelles incorporated with MTX for cancer chemotherapy

Yong Sun,Yihang Huang,Shaoquan Bian,Jie Liang,Yujiang Fan,Xingdong Zhang

Reduction-breakable core–shell type polymeric micelles from reduction-degradable amphiphilic polyethylene glycol- b –polyamide amine- b –polyethylene glycol triblock copolymers (PEG- b –PAA- b –PEG) were prepared as new drug carriers of methotrexate (MTX) for cancer chemotherapy. The PEG- b –PAA- b –PEG copolymers were synthesized in a simple one-step process under mild condition through Michael addition. Spherical micelles with diameters ranging from 65 to 123   nm were successfully fabricated from the copolymers. These micelles could effectively encapsulate the anti-cancer drug MTX in the core with drug loading content around 13%. The incorporation of MTX resulted in a little size increase but did not influence the morphology of micelles. The drug was hardly released from the micelles in normal condition without DDT as the reductant, but fast released up to 100% within 24   h when the structure of micelle core was broken in the presence of DTT, thus provided a potential tool for tumor targeting delivery of MTX using the higher concentration of reductant in tumor tissues. The proliferation inhibition experiments demonstrate that MTX-encapsulated micelles show significant cytotoxicity to KB, HepG2 and 4T1 tumor cells, especiallythe 4T1 cells.

Phosphate functionalized poly(vinyl alcohol)/poly(acrylic acid) (PVA/PAA): an electrospinning nanofiber for uranium separation

Xie Jinhua,Lv Riwen,Peng Hong,Fan Jiali,Tao Qinqin,Dai Ying,Zhang Zhibin,Cao Xiaohong,Liu Yunhai

With the aim of capturing uranium from water mediums phosphate functionalized poly(vinyl alcohol)/poly(acrylic acid) (PVA/PAA) nanofiber (PVA/PAA-PO 4 ) was firstly fabricated using the electrospinning method of fast process and high efficiency. The as-prepared PVA/PAA-PO 4 showed excellent water stability and tensile strength besides competitive uranium uptake capacity of 277.78 mg/g. Phosphate played a vital role in the structure of PVA/PAA-PO 4 for the attractive uranium uptake capacity. PVA/PAA-PO 4 was characterized by SEM, XPS, FT-IR and omnipotence machine. The effects of pH, ionic strength, oscillation time, initial uranium concentration and temperature on the uranium adsorption with PVA/PAA-PO 4 were studied. The elution with different kinds of acids was conducted and the reusability through the adsorption-desorption cycle test was carried out. The work provided a promising candidate for uranium separation from aqueous solution.

Enhancing the Toughness of PAA/LCNF/SA Hydrogel through Double-Network Crosslinking for Strain Sensor Application

Xin Li,Hui Gao,Qiang Wang,Shanshan Liu

Lignin-containing nanocellulose fibers (LCNF) have been considered as a valuable enhancer for polyacrylic acid (PAA)-based hydrogels that can form rigid porous network structures and provide abundant polar groups. However, the PAA–LCNF hydrogel is dominated by a single-network (SN) structure, which shows certain limitations when encountering external environments with high loads and large deformations. In this paper, sodium alginate (SA) was introduced into the PAA–LCNF hydrogel network to prepare a double-network (DN) hydrogel structure of the SA-Ca2+and PAA–LCNF through a two-step process. The covalent network of PAA–LCNF acts as the resilient framework of the hydrogel, while the calcium bridging networks of SA, along with the robust hydrogen bonding network within the system, function as sacrificial bonds that dissipate energy and facilitate stress transfer. The resulting hydrogel has porous morphologies. Results show that SA can effectively improve the mechanical properties of DN hydrogels and endow them with excellent thermal stability and electrical conductivity. Compared with pure PAA–LCNF hydrogel, the elongation at break of DN hydrogel increased from 3466% to 5607%. The good electrical conductivity makes it possible to use the flexible sensors based on DN hydrogel to measure electrophysiological signals. Our results can provide a reference for developing multifunctional hydrogels that can withstand ultra large deformation.

Label-Free Detecting of the Compaction and Decompaction of ctDNA Molecules Induced by Surfactants with SERS Based on a nanoPAA-ZnCl2-AuLs Solid Substrate

Bojuan Hao,Kaige Wang,Yukun Zhou,Chaofan Sui,Lei Wang,Ren Bai,Zhaojin Yang

DNA molecular compaction/decompaction is of great significance for the exploration of basic life processes, the research of biomedical and genetic engineering, and so forth. However, the detailed mechanism of DNA compaction/decompaction caused by surfactants remains an open and challenging problem that has not been fully solved so far. In this paper, a sort of novel solid substrate, nanoPAA-ZnCl2-AuLs, with good stability and high sensitivity, was prepared by a self-assembly method. Based on this substrate, the surface-enhanced Raman scattering (SERS) technology was employed to investigate characteristics of interactions between DNA molecules and surfactants at a single molecular level. SERS spectra of calf thymus DNA (ctDNA), cetyl trimethyl ammonium bromide (CTAB), and sodium dodecyl sulfate (SDS) with a concentration as low as 10–9 M, and SERS spectra of ctDNA–CTAB and ctDNA–CTAB–SDS composites were collected, respectively. The interactions between ctDNA and surfactants were analyzed by changes in SERS spectra, for example, disappearances and appearances of SERS bands and relative changes of peak intensity, in which CTAB resulted in the compaction of the DNA molecule while SDS induced the decompaction of the ctDNA–CTAB complex. Moreover, UV–visible spectrophotometry was employed to demonstrate the compaction/decompaction of ctDNA molecules caused by surfactants. The local binding modes of ctDNA molecules and surfactant molecules were expounded. This work will be helpful for understanding biological processes such as DNA compaction and recombination within nucleus or/and cells and for the development of gene therapy technologies.

Improved negative charge of tight ceramic ultrafiltration membranes for protein-resistant and easy-cleaning performance

Yahan Ye,Qing Han,Chen Zhao,Wei Ke,Minghui Qiu,Xianfu Chen,Yiqun Fan

Fouling caused by adsorption is a challenge in protein separation and purification using membrane technology. The interaction between the membrane surface and proteins is significant for developing antifouling modified membranes. In this study, a negative ZrO 2 tubular ceramic membrane was constructed by grafting polyacrylic acid (PAA) to mitigate protein fouling. PAA of 2000 Da had little effect on the membrane pore and surface wettability, as characterized by XPS, dextran retention, contact angle, and water permeance. The protein resistance of the modified membrane was investigated by protein filtration. The modified membranes had a higher stable normalized flux (0.6) and flux recovery ratio (90 %) than that of the original membrane. In addition, the performance of the modified membranes was sensitive to the pore sizes of the original membranes. When the original membrane was unable to completely reject bovine serum albumin (BSA), the weak interaction between BSA and the membrane pores would reduce rejection after PAA modification. And the flux recovery ratio of modified membrane increased by 55 %. Overall, PAA modification reduces irreversible fouling by electrostatic repulsion, and improves the protein-resistant and easy-cleaning performance of ceramic membranes.

Facile fabrication of polymer-based Fe3O4/HAp/PAA/PAM nanohybrid and it’s application for removal of dye

Wu Rui,Tian Guanghui,Liu Cunfang,Li Yapeng

The controlled synthesis of hybrids nanoparticles (NPs) and polymer have received significant attention for application in environment. In the paper, green and multifunctional polymer-based Fe 3 O 4 /hydroxyapatite (HAp)/polyacrylic acid (PAA)/ polyacrylamide (PAM) nanohybrids with magnetism was fabricated by polymerization. The obtained materials (Fe 3 O 4 /HAp/PAA/PAM) was characterized by hysteresigraph, X-Ray diffractometer (XRD), infrared spectrometer (IR), energy dispersive spectroscopy (EDS), mapping, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM). The decontaminating performance of the nanohybrids was evaluated by adsorption methylene blue (MB). Adsorption kinetics and adsorption isotherms were employed to examine the adsorption behavior. The results showed that the adsorption process fitted the Langmuir isotherm and pseudo-second-order kinetic model and Fe 3 O 4 /HAp/PAA/ PAM displayed appreciable adsorption efficiency. The adsorption mechanism was also presumed. The removal of dye mainly attributed to polymer with multifunctional groups and the special structure of HAp. Moreover, it is facile to retrieve due to the incorporation of Fe 3 O 4 with strong magnetism. It proposed a novel route to design and fabricate multifunctional nanohybrid adsorbent for removal of dye with high capacity.

PAA/PVA/PEDOT:PSS/Ti3C2TX Hydrogel Strain Sensor with Enhanced Performance for Information Encryption and Wireless Motion Monitoring

Long Yu,Yi’na Yang,Tianran Zhao,Liyang Zhao,Jia Chen,Chunna Yu,Chang Zhao,Guangjian Xing

As biocompatible soft materials with stimuli-responsive characteristics, wearable strain sensors based on conductive hydrogels hold substantial promise across diverse engineering fields. However, their practical applications are often hindered by limited sensitivity and issues related to single functionality. This study presents a multifunctional composite hydrogel composed of PAA/PVA/PEDOT:PSS/Ti3C2TX designed for flexible strain sensors and synthesized through a straightforward one-pot polymerization technique. The incorporation of Ti3C2TX MXene nanosheets significantly enhances the porous architecture and mechanical properties of the hydrogel. This hydrogel features a combination of covalent and physical cross-linking networks, showcasing remarkable elastic recovery, puncture resistance, stretchability, robust interfacial adhesion, and self-healing capabilities. The hydrogel-based strain sensor demonstrates exceptional performance, including high sensitivity (GF = 21.36 in the 31–50% strain range), a low detection limit (53.0 Pa), rapid response and recovery times (42 ms/38 ms), and long-term stability (>1,600 cycles). Its practical applications in information encryption, handwriting recognition, and wireless robotic motion monitoring highlight its potential as a versatile platform for advanced flexible sensing technologies.

Multifunctional Crosslinked PAA–TA Binder: Robust Structural Integrity and Suppressed Manganese Dissolution for High–Performance LiMn0.6Fe0.4PO4 Cathodes

A poly (acrylic acid–tannic acid) (PAA–TA) crosslinked composite is reported on for the first time as an aqueous binder for LiMn0.6Fe0.4PO4(LMFP) cathodes to suppress manganese dissolution. Benefiting from hydrogen bonding and chemical crosslinking, the PAA-TA binder constructs a robust three-dimensional network that strengthens the interfacial adhesion among active particles, conductive additives, and the current collector, stabilizing the LMFP crystal structure upon cycling. More importantly, this polymeric network effectively restrains manganese leaching, which is the major origin of the capacity fading of LMFP cathodes. Meanwhile, continuous electron and ion transport pathways are well established. The LMFP electrode with an optimized PA5TA1 binder delivers a reversible capacity of 112 mAh g−1at 5 C and retains 81.3% of its capacity after 300 cycles, outperforming the PVDF/LMFP electrode. Post–mortem analyses of cycled LMFP cathodes further confirm that there was substantially suppressed Mn2+dissolution in the PAA–TA electrode, corroborating the structural integrity of the cathode–electrolyte interface. This crosslinked aqueous polymer provides a sustainable alternative to the PVDF binder for long–life LMFP cathodes.

Enhanced immunofluorescence detection of a protein marker using a PAA modified ZnO nanorod array-based microfluidic device

Zhihua Wu,De Zhao,Chengyi Hou,Lei Liu,Jianhua Chen,Hui Huang,Qinghong Zhang,Yourong Duan,Yaogang Li,Hongzhi Wang

Zinc oxide (ZnO) often serves as protein microarray substrates owing to its outstanding fluorescence enhancement effect. However, the integration of functional substrates with microfluidic technology to detect cancer biomarkers still needs to be optimized and promoted, for example, the optimization of micro/nanostructure and hydrophilic modification strategies for fluorescence immunoassays. Here, ZnO nanorod arrays were constructed on the inner wall of glass capillaries through a microfluidic chemical method, and the electrostatic layer by layer self-assembly was applied to modify the nanorod array with hydrophilic polyelectrolyte-polyacrylic acid (PAA). The effects of the flow rate and the reagent concentration on the morphology of the ZnO nanorod array were investigated. The ZnO nanorod array-based glass capillary, prepared at 25 μL min−1 for 4 min with 50 mM Zn2+ in solution, showed a remarkable enhancement in fluorescence performance. In addition, the introduction of PAA suppressed the interference of nonspecific protein and improved the antibody loading capacity effectively. In the detection of carcinoembryonic antigen, the limit of detection reached 100 fg mL−1, which indicated that the ZnO@PAA nanorod array-based microfluidic device exhibits remarkable fluorescence detection performance towards protein markers and possesses potential to be applied to point-of-care diagnostics and high throughput cancer biomarker detection.

A rheumatoid arthritis magnetic resonance imaging contrast agent based on folic acid conjugated PEG-b-PAA@SPION

Yanqi Zhong,Fengying Dai,Heng Deng,Meihong Du,Xiaoning Zhang,Qingjun Liu,Xin Zhang

Superparamagnetic iron oxide nanoparticles (SPIONs) offer unique properties for magnetic resonance imaging (MRI). Targeting imaging of rheumatoid arthritis in vivo requires a specific, magnetic sensitive and ultra-stable MRI contrast agent. In this study, SPIONs with a preferable colloid stability and optimized size were obtained by using an in situ polyol method with the diblock copolymer PEG-b-PAA acting as a surface ligand. Increasing the degree of polymerization (DP) of PAA from 18 to 36 to 57 led to the decreasing size of the iron oxide nanoparticles from 52 nm to 17 nm to 9 nm, respectively. Folic acid was conjugated onto PEG-PAAx@SPION as a specific targeting molecule for activated macrophages in a rheumatoid arthritis joint. To evaluate the stability and magnetic properties of the particle, a series of tests were conducted to evaluate and optimize the nanoparticles. In vitro endocytosis experiments confirmed the better performance of the folic acid conjugated SPIONs than the non-folic acid modified SPIONs. In vivo MRI clearly demonstrated the significant signal diminishment of the arthritis joint in antigen induced arthritis (AIA) rats by intravenous injection of the optimized nanoparticles FA–PEG-b-PAA36@SPION. These results indicated that FA–PEG-b-PAA36@SPION could serve as a promising candidate for the MRI of rheumatoid arthritis.