Surface Modification Research Articles

Development and antibacterial evaluation of a dopamine-modified curcumin@zinc-based organic framework.

Antibiotics are crucial for treating and preventing bacterial infections. However, the widespread use of antibiotics has led to serious antibiotic resistance issues. To address the growing threat of antibiotic-resistant bacterial infections, we designed and synthesized an antibacterial composite material, CCM@ZIF-8@PDA, through a one-pot method and surface modification strategy. This material combines the antibacterial properties of the natural product curcumin, the advantages of ZIF-8, and the photothermal conversion capability of PDA. It exhibits three antibacterial mechanisms against S. aureus: chemical antibacterial, ionic antibacterial, and photothermal antibacterial effects. At a low concentration of 100 ppm, CCM@ZIF-8@PDA achieves a 100% antibacterial rate. This multi-modal antibacterial strategy provides insights for developing new antibacterial materials to combat antibiotic resistance.

Bioinspired solid-state nanochannels for molecular analysis.

The acute sensory behaviour in living organisms relies on the highly efficient transport behaviour of ions in biological nanochannels, which has inspired the design and applications of artificial solid-state nanochannels in the field of sensitive analysis. The application of nanochannels for analysis is now widely investigated, and a variety of sensors have been developed. By coupling reliable nanochannel fabrication techniques with a multitude of surface modification strategies, novel sensors with customized sensing capabilities are generated by the integration of recognition elements and nanochannels. The altered physicochemical properties of these solid-state nanochannel sensors will be manifested by steady-state currents when they are affected by the target analyte. In this mini-review, we focus on emerging solid-state nanochannels based on different fabrication processes such as electron-beam etching, anodic oxidation, ion track etching, and self-assembly. Also, modifications of recognition elements are discussed, including nucleic acids, proteins, small molecules, and responsive materials. The key factors of ion transport behaviour during detection are also reviewed, including surface charge, channel size, and wettability. The applications of these bioinspired nanochannels in the exploration of analysis of small molecules (gas molecules, drug molecules and biological molecules) are concisely presented. Furthermore, we discuss the future developments and challenges.

Study on armature ablation resistance enhanced by surface modification of FeCr2-xNiCoAlx

Study on armature ablation resistance enhanced by surface modification of FeCr2-xNiCoAlx

Surface modification of lithium metal anode using polar polymer-in-ceramic electrolytes by grafting of anti-perovskite for inhibition dendrite growth

Surface modification of lithium metal anode using polar polymer-in-ceramic electrolytes by grafting of anti-perovskite for inhibition dendrite growth

An electrochemical immunosensor based on a nano-ceria integrated microfluidic chip for interleukin-8 biomarker detection.

Interleukin-8 (IL8) is an important cytokine that plays a significant role in tumor growth and angiogenesis across various malignant tumors, including oral squamous cell carcinoma (OSCC). It is an important biomarker for oral cancer; therefore, its early and accurate detection in bodily fluid reduces morbidity and mortality rates in cancer patients. The work presents the development of a label-free microfluidic miniaturized electrochemical immunosensor for IL8 biomarker detection at low concentration in saliva samples. A rapid, sensitive and selective biosensing platform was developed for IL8 detection using a nano-ceria integrated microfluidic system. The synthesized nano-ceria particles (8.13 nm) were employed to enhance the electrochemical biosensing signal and sensitivity of the biosensor due to their high catalytic properties and large surface area. For this, microfluidic chip was prepared by Indium tin oxide (ITO) (3 × 4 cm) containing three electrode patterns of working, reference and counter electrode. These electrode patterns were developed using a maskless photolithography technique and a polydimethylsiloxane (PDMS) mold created a 200 μm wide microchannel which was bound to the susbtrate using plasma treatment. Spectroscopy and microscopy techniques were used to confirm the synthesis of nano-ceria. Furthermore, electrode surface modifications were achieved by immobilization of chemically activated antibodies of IL8, as verified by Fourier transform-infrared spectroscopy (FT-IR). Furthermore, differential pulse voltammetry (DPV) was utilized to investigate electrochemical parameters and conduct biosensing studies. The developed electrochemical microfluidic biosensing platform works for an IL8 antigen in the concentrations ranging from 0.004 to 10 ng mL-1 with a limit of detection (LOD) and limit of quantification (LOQ) of 0.0001 ng mL-1 and 0.0006 ng mL-1, respectively. Moreover, the developed electrochemical biosensing platform was validated using human saliva samples, achieving percentage recovery within an acceptable range.

Nanoscale surface modifications of diamond-like carbon films by in situ laser irradiation in atomic force microscope

Nanoscale surface modifications of diamond-like carbon films by in situ laser irradiation in atomic force microscope

A Review on the Applications of Quantum Dots in Sample Preparation.

In recent years, despite significant advances in preconcentration and preparation techniques that have led to efficient recovery and accurate measurement of target compounds. There is still a need to develop adsorbents with unique and efficient features such as high pore volume and surface area, reactivity, easy synthesis, low toxicity, and compatibility with the environment, which increase the adsorption capacity and increase extraction efficiency. Semiconductor nanocrystals called quantum dots (QDs) with a size of less than 10nm are three-dimensional nanoparticles with a spherical, rod, or disc structure that have significant potential in extraction as adsorbents due to their excellent properties such as low toxicity, reactivity, environmental friendliness, and hydrophilic and hydrophobic interactions. One of the most basic issues in the development of adsorbents is to increase the effective surface and, as a result, their extraction efficiency. QDs, having an effective surface much higher than conventional nanomaterials, are a suitable option for extracting target compounds in different environments. This work comprehensively reviews QD-based extraction methods and surface modification strategies of QDs based on functional groups, ligands, and materials from 2013 to 2024. In addition, the applications of QD-based composites for the extraction of organic and inorganic analytes (residues of drugs in human blood and plasma, toxins, pesticides, pollutants from chemical industries, heavy metals, etc.) in different matrices are investigated.

Surface modification of titanium alloy using a novel elastic abrasive jet machining method

Surface modification is always employed to enhance surface integrity, where abrasive jet machining (AJM) represents a large portion. This paper investigates the impact of a new elastic abrasive jet machining (EAJM) method on the surface characteristics of Ti6Al4V alloy. A self-developed multi-element polymer microbead covered by diamond powders is employed as the abrasive with a hardness of approximately 50–80 HV. This study systematically examines and compares the performance of elastic and hard abrasives in surface modification of Ti6Al4V by AJM, investigating the effects of nozzle pressure (P) and traverse speed (v) on surface integrity. The lowest surface roughness and highest microhardness are achieved by EAJM under the condition of P = 350 kPa and v = 0.75 mm/s. Hard abrasive jet machining (HAJM) tends to produce poor surface quality when excessive parameters are applied, while the performance of EAJM is relatively stable. The most compressive residual stresses obtained by EAJM and HAJM are −300 and − 140 MPa, respectively. EAJM is able to modify the surface characteristics and produce a better surface quality with a lower material removal amount compared to HAJM. In addition, the relatively lower crushing rate of the elastic matrix and the fact that the material removal capability of EAJM relies on the diamond powders on the abrasive surface make it easier for EAJM to maintain its performance.

Morphological tuning-driven high-performance separator for alkaline water electrolyzer through the surface modification of mechanical support

Morphological tuning-driven high-performance separator for alkaline water electrolyzer through the surface modification of mechanical support

Synthesis and Performance of Polysulfone-Chitosan Ultrafiltration Membranes for Humic Acid Removal

Natural organic matter (NOM) constitutes a significant contaminant in water sources, adversely affecting drinking water quality and complicating purification processes. To mitigate these contaminants, the current state of the application uses membrane filtration along with structural and surface modification of membranes. This study presents the development of polysulfone (PSU) flat-sheet ultrafiltration (UF) membranes, modified with three different concentrations of chitosan (0.05, 0.06, and 0.08g), a natural polymer, to enhance NOM removal. The membranes were rigorously characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and water contact angle (WCA), porosity, and pore size analysis. Furthermore, the study delves into the interaction mechanisms between chitosan and the PSU polymer matrix, as well as the transport phenomena involved. The findings indicate that increasing the chitosan content from 0.05 to 0.08g markedly enhanced the membrane's surface properties, reducing the contact angle from 72.8° to 53.5° and nearly doubling the permeation rate despite the decrease in porosity and pore size. The PSU UF membrane with 0.08g chitosan demonstrated a superior humic acid (HA) rejection rate of 90%, underscoring chitosan's potential for improving polymeric membranes in NOM removal applications.

Advancing cellular transfer printing: achieving bioadhesion-free deposition via vibration microstreaming.

Cell transfer printing plays an essential role in biomedical research and clinical diagnostics. Traditional bioadhesion-based methods often necessitate complex surface modifications and offer limited control over the quantity of transferred cells. There is a critical need for a modification-free, non-labeling, and high-throughput cell transfer printing technique. In this study, an adhesion-free cellular transfer printing method based on vibration-induced microstreaming is introduced. By adjusting the volume of the microcavity, the number of cells transferred per microtiter well can be realized to the level of a single cell. Additionally, it allows for precise control of large-scale cellular spatial distribution, leading to the formation of biomimetic patterns. Moreover, the demonstrated biocompatibility and high throughput of this cell transfer printing method highlight its potential utility. The correspondence of the transferred cell amount to the vibration and frequencies allows the system to exhibit excellent tunability of the transferred cell amount and pattern. This bioadhesion-free cell transfer printing method holds promise for advancing cell manipulation in biomedical research and analysis.

Stability of electrostatically stabilized Pickering emulsion of silica particles and soy hull polysaccharides: Mechanism of pH and ionic strength.

To enhance the surface hydrophobicity and emulsification capacity of silica colloidal particles, a natural surface modification of soy hull polysaccharides (SHP) was conducted. Here, the effects of pH and ionic strength on the stability, microstructure and rheological properties of concentrated Pickering emulsions were investigated. Experimental results show emulsions gelled at pH2, with increasing pH (2-10), SiO2-SHP absolute zeta potential (from -19.6 to -44.7mV) and interfacial tension (from 15.2 to 25.09 mN/m) increased, and viscosity, viscoelasticity and storage stability decreased. Additionally, at low NaCl concentrations (<150mM), SiO2-SHP interfacial tension remained low (21.3 mN/m), promoting stable emulsions (TSI<1.5). In this case, the electrostatic interaction was slightly affected by ions, facilitating the occurrence of composite coagulation. However, as ionic concentration increased (150-300mM), interfacial tension increased (from 20.5 to 27.6 mN/m). Thus, our study presents important insights into the pH and salt ions dependent mechanism of emulsion stabilization by SiO2-SHP.

In Vitro Evaluation of Bacterial Adhesion of Streptococcus mutans and Enterococcus faecalis on Sand-Blasted, Acid-Etched, and Anodized Titanium Dental Implants.

Although the surface modifications of the implant have been widely proposed to enhance the osseointegration, their impact on microbial adhesion is still not explored. The present in vitro study was done to compare the bacterial adhesion of S. mutans and Enterococcus faecalis on sand-blasted acid-etched and anodized titanium dental implants. Three commercially available implants, namely SLA (n = 3), SLActive (n = 3), and TiUnite (n = 3), were inoculated with the prepared broth suspension of S. mutans and E. faecalis, and were incubated at 37°C for 48 h. After incubation, the colonies were counted using direct microscopy and the results were recorded as colony forming units/mL (CFU/mL). Mean CFUs were compared between the three implants by ANOVA and pairwise comparison by Tukey's HSD post hoc test using SPSS Software. p value of < 0.05 was considered to be statistically significant. TiUnite implant showed the highest bacterial adherence for S. mutans (3.49 ± 0.53 × 102 CFU/mL) and E. faecalis (35.14 ± 1.54 × 102 CFU/mL) followed by SLA and SLActive. These data demonstrated statistically significant differences between the three types of implants (P < 0.05). Pairwise comparison showed that there was a statistically significant difference between SLA and TiUnite (P = 0.004) and SLActive and TiUnite (P = 0.001) in terms of S. mutans colony count. In terms of E. faecalis colony count, there was a statistically significant difference between SLA and SLActive (P = 0.000), SLA and TiUnite (P = 0.000) and SLActive and TiUnite (P = 0.000). Compared with sand-blasted and acid-etched dental implants, anodized dental implants showed higher adhesion of S. mutans and E. faecalis.

Surface modification of MOFs towards flame retardant polymer composites

Methods for modifying the surface structure of MOFs are categorized and flame-retardant effects of various modification techniques are examined, emphasizing the development of MOF surface morphology and its compatibility with the polymer matrix.

Applications and latest research progress of liposomes in the treatment of ocular diseases.

The special structure of eyes and the existence of various physiological barriers make ocular drug delivery one of the most difficult problems in the pharmaceutical field. Considering the problems of patient compliance, local administration remains the preferred method of drug administration in the anterior part of eyes. However, local administration suffers from poor bioavailability, need for frequent administration, and systemic toxicity. Administration in the posterior part of the eye is more difficult, and intravitreal injection is often used. But intravitreal injection faces the problems of poor patient compliance and likely side effects after multiple injections. The development of nanocarrier technology provides an effective way to solve these problems. Among them, liposomes, as the most widely used carrier in clinical application, have the characteristics of amphiphilic nanostructure, easy surface modification, extended release time, good biocompatibility, etc. The liposomes are expected to overcome obstacles and effectively deliver drugs to the target site to improve ocular drug bioavailability. This review summarized the various controllable properties of liposomes for ocular delivery as well as the application and research progress of liposomes in various ocular diseases. In addition, we summarized the physiological barriers and routes of administration contained in eyes, as well as the prospects of liposomes in the treatment of ocular diseases.

Study on the influence of multi-energy field combined surface modification on the subsurface microstructure evolution of AA7075 aluminum alloy

Study on the influence of multi-energy field combined surface modification on the subsurface microstructure evolution of AA7075 aluminum alloy

Free radical synthesis of succinic anhydride grafted poly(lactic acid) porous templates for sustained drug delivery in the buffer media.

Poly(lactic) (PLA) is a biodegradable material obtained from renewable resources and is recognized as a safe biopolymer by the Food and Drug Administration. PLA expresses excellent mechanical and moldability attributes nonetheless poor elasticity/functionality limits its widespread utilization. One approach to compensate for this is chemical surface modification through free radical grafting with small organic molecules like maleic anhydride (MA). The study undertakes the synthesis of succinic anhydride (SA)-grafted PLA [SA-g-PLA] films for sustained drug delivery applications. The entrapped porogen was leached out under alkaline treatment to make the PLA film porous by creating channels/cavities for drug inclusion. The success of the surface treatment of PLA-based films was investigated using specific chemical analyses. The results demonstrated the hydrophilic nature (water contact angle of 31°) of the SA-g-PLA films for the prevalence of MA (1780 cm-1) and methylamine (340-640 cm-1) congeners as expressed under FTIR analysis. The SA-g-PLA film expressed a crystallinity of 72.41 % and a melting temperature of 201.9 °C. The SA-g-PLA film exhibited pH-responsive streptomycin sulfate uptake (pH 6.5) and release (pH 7.4) profiles and obeyed first-order kinetics. The SA-g-PLA porous films with potential modification would be a sustainable and biocompatible candidate for drug delivery applications.

Electrode functional microorganisms in bioelectrochemical systems and its regulation: A review.

Bioelectrochemical systems (BES) as environmental remediation biotechnologies have boomed in the last two decades. Although BESs combined technologies with electro-chemistry, -biology, and -physics, microorganisms and biofilms remain at their core. In this review, various functional microorganisms in BESs for CO2 reduction, dehalogenation, nitrate, phosphate, and sulfate reduction, metal removal, and volatile organic compound oxidation are summarized and compared in detail. Moreover, interrelationship regulation approaches for functional microorganisms and methods for electroactive biofilm development, such as targeted electrode surface modification, chemical treatment, physical revealing, biological optimization, and genetic programming are pointed out. This review provides promising guidance and suggestions for the selection of microbial inoculants and provides an analysis of the role of individual microorganisms in mixed microbial communities and its metabolisms.

Effect of urea solution medium mixed with Nano-graphene particles on the surface modification of titanium alloy by EDM

Effect of urea solution medium mixed with Nano-graphene particles on the surface modification of titanium alloy by EDM

CORROSION BEHAVIOUR OF ADVANCED COMPOSITES CONTAINING SURFACE MODIFIED SIC AS REINFORCEMENT

The interface structure, micro-voids, pits, delamination, intermetallic compounds and internal stresses are the utmost critical factors influencing the corrosion performance of composite materials making them unsuitable for use in structural applications. One useful technique to control such adverse effect in composites is surface modification of the reinforcement. The present investigation involved the implementation of chemical techniques, particularly electroless plating (EP), to modify the surface of silicon carbide (SiC) particles by depositing a layer of nickel phosphorous (Ni-P) onto them. These plated SiC particles were subsequently employed in the production of Al/Ni-pSiC composites using the powder metallurgy (PM) method, with different weight percentages of plated SiC content ranging from 5% to 15%. The corrosion behaviour was assessed by potentio-dynamic polarization tests in 3.5% NaCl solution at room temperature. Results confirmed that AlNi-pSiC composites exhibit a greater resistance to pitting, in contrast to pure aluminium and Al/SiC composites without plating. The enhanced corrosion resistance in Al/Ni-pSiC composites can be attributed to strong interfacial bond, grain refinement, CTE difference, formation of Ni3Al, and reduced potential difference.