查找使用阿拉丁产品的科研文献

A novel PVA/QCS/AgNP hydrogel with antibacterial and healing-promoting efficacy for preventing postoperative pancreatic fistula in rats

Yuan Zhou,Fangsheng Chen,Ronggui Lin,Heguang Huang,Maoen Pan

Postoperative pancreatic fistula (POPF), a life-threatening complication following pancreatic surgery, demands innovative biomaterials to prevent infection and promote healing simultaneously. Traditional sealants lack controlled degradation, mechanical robustness, and antibacterial efficacy. Here, we developed a multifunctional hydrogel composed of polyvinyl alcohol (PVA), quaternized chitosan (QCS), and silver nanoparticles (AgNPs) to address these challenges. The PVA/QCS/AgNP hydrogel was synthesized via UV-induced reduction of Ag⁺ and freeze‒thaw cycles, yielding a mechanically stable network with a uniform AgNP dispersion. In vitro, the hydrogel exhibited broad-spectrum antibacterial activity against Staphylococcus aureus , Escherichia coli , and other pathogens while maintaining > 90 % fibroblast viability. Its controlled AgNP release profile balanced antimicrobial potency and biocompatibility. In a rat pancreatic fistula model, the hydrogel significantly reduced fluid leakage and inflammation, accelerated collagen deposition, and normalized serum amylase levels within 14 days. A transcriptomic analysis revealed the upregulation of the cell cycle and extracellular matrix remodeling pathways, in addition to the suppression of proinflammatory cytokines, elucidating its dual roles in infection control and tissue regeneration. By integrating robust sealing, enzymatic resistance, and immunomodulatory properties, this hydrogel represents a clinically translatable solution for POPF management, outperforming conventional therapies and advancing the design of multifunctional biomaterials for complex surgical applications.

A direct assay of carboxyl-containing small molecules by SALDI-MS on a AgNP/rGO-based nanoporous hybrid film

Min Hong,Lidan Xu,Fangli Wang,Zhirong Geng,Haibo Li,Huaisheng Wang,Chen-zhong Li

Silver nanoparticles (AgNPs) and reduced graphene oxide (rGO) hybrid nanoporous structures fabricated by the layer-by-layer (LBL) electrostatic self-assembly have been applied as a simple platform for the rapid analysis of carboxyl-containing small molecules by surface-assisted laser desorption/ionization (D/I) mass spectrometry (SALDI-MS). By the simple one-step deposition of analytes onto the (AgNP/rGO)9 multilayer film, the MS measurements of various carboxyl-containing small molecules (including amino acids, fatty acids and organic dicarboxylic acids) can be done. In contrast to other energy transfer materials relative to AgNPs, the signal interferences of a Ag cluster (Agn+ or Agn−) and a C cluster (Cn+ or Cn−) have been effectively reduced or eliminated. The effects of various factors, such as the pore structure and composition of the substrates, on the efficiency of D/I have been investigated by comparing with the (AgNP)9 LBL nanoporous structure, (AgNP/rGO)9/(SiO2NP)6 LBL multilayer film and AgNP/prGO nanocomposites.

A recyclable PDMS microfluidic surface-enhanced Raman scattering Cu/AgNP chip for the analysis of sulfadiazine in aquatic products

Jianying Huang,Ling Xia,Xiaohua Xiao,Gongke Li

A copper/polydimethylsiloxane (Cu/PDMS) microfluidic chip was designed to synthesize SERS substrates through a displacement reaction between silver and copper in microfluidic channels to form a microfluidic SERS nanoparticles (AgNPs)/Cu chip. This SERS substrate fabrication method doesn’t require complex manufacturing processes or expensive equipment, and it can be achieved at room temperature in just 4 min. Meanwhile, the AgNPs grown on copper foil could offer ample hot spots, effectively boosting Raman signals of target molecules, and the enhancement factor (EF) was 5.12 × 107 for methylene blue, 4.08 × 107 for crystal violet, and 4.81 × 105 for sulfadiazine. The chip could be reused at least 9 times with consistent signal performance. Combined with the concentration gradient microchannel network design, we could establish the standard curve for samples through one injection on a single chip. A rapid SERS method for detecting sulfadiazine in aquatic products was developed. The linear range for sulfadiazine analysis was 75.0–1000 μg L−1 with a limit of detection of 28.4 μg L−1. Sulfadiazine was found in aquatic products (43.8 μg kg−1), with recovery rates ranging from 82.7% to 110%. The result was validated using high-performance liquid chromatography, showing a relative error of 9.3%. The entire detection procedure could be completed in just 20 min to detect sulfadiazine. These results demonstrate that the developed SERS method is fast, accurate, and reliable for analysis of sulfadiazine in aquatic products.

Does artificial light at night change the impact of silver nanoparticles on microbial decomposers and leaf litter decomposition in streams?

Gaozhong Pu,Danjuan Zeng,Ling Mo,Wen He,Longwu Zhou,Kechao Huang,Jianxiong Liao,Shuo Qiu,Shengfeng Chai

The toxic effects of silver nanoparticles (AgNP) to aquatic species and ecosystem processes have been the focus of increasing research in ecology, but their effects under different environmental stressors, such as the ongoing anthropogenic artificial light at night (ALAN) which can cause a series of ecological effects and will potentially interact with other stressors, remain poorly understood. Here, we aimed to assess the combined effects of AgNP and ALAN on the activities and community structure of fungi and bacteria associated to plant litter in a stream. The results showed that ALAN not only led to changes in the average hydrodynamic diameter, ζ-potential and dissolved concentration of AgNP but also inhibited the enzyme activities of leucine-aminopeptidase (LAP), polyphenol oxidase (PPO) and peroxidase (PER) associated with microbes involved in litter decomposition. The negative effect of AgNP on the decomposition of Pterocarya stenoptera leaf litter was alleviated by ALAN owing to the reduction of the Ag+ concentration in the microcosm and of the lignin content of the leaf litter in the A-AgNP treatments, the enhancement of β-glucosidase (β-G) activities and the increase in microbial biomass. The effect of ALAN alone or combined with AgNP or AgNO3 on the taxonomic composition of fungi was much greater than that on bacteria. Linear discriminant analysis effect size (LEfSe) demonstrated that each treatment had its own fungal and bacterial indicator taxa, from the phylum to genus levels, indicating that the microbial communities associated with litter decomposition can change their constituent taxa to cope with different stressors. These results reveal that ALAN can decrease the toxicity of AgNP and highlight the importance of considering ALAN during the assessment of the risk posed by nanoparticles to freshwater biota and ecosystem processes.

One-Step Preparation of an AgNP-nHA@RGO Three-Dimensional Porous Scaffold and Its Application in Infected Bone Defect Treatment

Weizong Weng,Xiaoqun Li,Wei Nie,Haoyuan Liu,Shanshan Liu,Jianming Huang,Qirong Zhou,Jia He,Jiacan Su,Zhifeng Dong,Dongliang Wang

A plasmonic AgNP decorated heterostructure substrate for synergetic surface-enhanced Raman scattering identification and quantification of pesticide residues in real samples

Xueting Li,Chenyue Xu,Lan Yan,Yating Feng,Haoyue Li,Cheng Ye,Maofeng Zhang,Changlong Jiang,Jianhua Li,Yucheng Wu

Rapid and on-site Raman spectroscopic identification and quantification of pesticide residues have been restricted to the low instrumental sensitivity of a portable Raman instrument, and no ideal platforms have been reported for analyzing pesticides on real sample surfaces. An efficient method to improve the detection sensitivity is to fabricate a highly sensitive surface-enhanced Raman scattering (SERS) substrate. Here, we present a MOF-derived ZnO@TiO2 heterostructure combined with plasmonic AgNPs as a SERS sensor to achieve synergetic EM and CM enhancement, exhibiting high sensitivity, excellent signal reproducibility (RSD < 5.9%) and superior stability for analysis of model molecules. The SERS sensor achieved a low detection concentration of 10−8 M for both CV and R6G molecular solutions on a portable Raman device. As a proof of concept, we modelled a pesticide residue on real samples of dendrobium leaves. Thiram, triazophos and fonofos solutions were selected as analytes for mimicking the function of on-site analysis. The SERS analytical platform showed not only high sensitivity for single- and multi-component identification, but also quantitative detection of pesticide residues on dendrobium leaves. These preliminary investigations indicate that this SERS analytical platform will allow the development and potential applications in rapid and on-site pesticide analysis.

SERS determination of sodium saccharin content on the tipping paper of cigarettes using AgNP substrates prepared with a USB-power supply device

Huipeng Deng,Zakir H. Talpur,Kaijun Wang,Yan Kang,Yiping Du,Dongmei Xu,Xinglong Fan,Wei Li

A novel magnetic agitating heater powered by a USB port has been developed and applied to synthesize silver colloid substrate for surface-enhanced Raman scattering (SERS) detection of sodium saccharin content on the tipping paper of cigarettes. The heater device allows the convenient synthesis of the Ag colloid, and the reaction can be completed on-site in 15 min under mild conditions. The on-site synthesis of SERS substrate effectively avoided the need for storage and concerns regarding the poor stability and short lifespan of colloid substrates. The results demonstrated that the substrate obtained with the device could achieve SERS detection of Rhodamine 6G (R6G) at as low as 10−9 mol L−1 while maintaining a stable intensity with a relative standard deviation (RSD) of 5.52% (n = 5). Using the prepared substrate at the optimal conditions, the limit of detection of sodium saccharin (SS) was 1 mg L−1. By introducing an internal standard KSCN, a linear relationship was observed between the relative intensity at 708 cm−1 and the concentration of the SS in a range of 20–100 mg L−1 (R2 = 0.98). With the developed method, SS was directly extracted from the cigarette paper by immersing it in water, and the extracted solution was subsequently detected. The quantitative spike-recoveries were in the range of 95.5–116.7%, with RSD between 2.3–12.6%. The whole detection procedure including the on-site substrate preparation, took only about 30 min. This work opens new avenues for colloidal synthesis, and the detection method of SS on the cigarette paper also holds great promise in food safety applications.

Dual Functions of a Au@AgNP-Incorporated Nanocomposite Desalination Membrane with an Enhanced Antifouling Property and Fouling Detection Via Surface-Enhanced Raman Spectroscopy

Shixin Zhang,Durga P. Acharya,Xiaomin Tang,Huaili Zheng,Guang Yang,Derrick Ng,Zongli Xie

Membrane fouling has remained a major challenge limiting the wide application of membrane technology because it reduces the efficiency and shortens the lifespan of the membrane, thus increasing the operation cost. Herein we report a novel dual-function nanocomposite membrane incorporating silver-coated gold nanoparticles (Au@AgNPs) into a sulfosuccinic acid (SSA) cross-linked poly(vinyl alcohol) (PVA) membrane for a pervaporation desalination. Compared with the control PVA membrane and PVA/SSA membrane, the Au@AgNPs/PVA/SSA membrane demonstrated a higher water flux and better salt rejection as well as an enhanced antifouling property. More importantly, Au@AgNPs provided an additional function enabling a foulant detection on the membrane surface via surface-enhanced Raman spectroscopy (SERS) as Au@AgNPs could amplify the Raman signals as an SERS substrate. Distinct SERS spectra given by a fouled membrane helped to distinguish different protein foulants from their characteristic fingerprint peaks. Their fouling tendency on the membrane was also revealed by comparing the SERS intensities of mixed foulants on the membrane surface. The Au@AgNPs/PVA/SSA nanocomposite membrane presented here demonstrated the possibility of a multifunction membrane to achieve both antifouling and fouling detection, which could potentially be used in water treatment.

An aptamer biosensor based dual signal amplification system for the detection of salmonella typhimurium

Ao Li,Peng Zuo,Bang-Ce Ye

Salmonella, a typical foodborne pathogen, always seriously threatens the health and even life of both humans and animals. However, highly sensitive and fast quantitative methods for its detection are remaining to be challenged. Herein, we presented an efficient method with dual signal amplification strategy by combining immune hybridization chain reaction (HCR) with surface enhanced Raman scattering (SERS) to high sensitively detect Salmonella typhimurium in food. After sample preparation, S. typhimurium were specifically captured by immunomagnetic beads (IMBs), then aptamers and hairpin-probes were added to trigger HCR to form nicked dsDNA, finally 4’,6-Diamidino-2-phenylindole dihydrochloride (DAPI) was incubated with HCR products and then the whole system was mixed with AgNP colloid to detect the SERS intensity at 1610 cm −1 . As a result, a good linear relationship was achieved between SERS intensities and corresponding concentrations of S. typhimurium ranging from 10 to 10 5  CFU/mL, with a limit of detection (LOD) of 6 CFU/mL in 3.5 h. The proposed method has been successfully applied to capture and detect the S. typhimurium in spiked milk samples, and the results were consistent with those of the traditional plate counting method. The method, with combination of HCR and SERS, achieves double amplification of the detection signal and significantly improves the detection sensitivity of S. typhimurium . And it also shows good application potential for the highly sensitive detection of other contaminants in food.