Modification Methodologies Research Articles

Efficient multiplex non-viral engineering and expansion of polyclonal γδ CAR-T cells for immunotherapy.

Gamma delta (γδ) T cells are defined by their unique ability to recognize a limited repertoire of non-peptide, non-MHC-associated antigens on transformed and pathogen-infected cells. In addition to their lack of alloreactivity, γδ T cells exhibit properties distinct from other lymphocyte subsets, prompting significant interest in their development as an off-the-shelf cellular immunotherapeutic. However, their low abundance in circulation, heterogeneity, limited methods for ex vivo expansion, and under-developed methodologies for genetic modification have hindered basic study and clinical application of γδ T cells. Here, we implement a feeder-free, scalable approach for ex vivo manufacture of polyclonal, non-virally modified, gene edited chimeric antigen receptor (CAR)-γδ T cells in support of therapeutic application. Engineered CAR-γδ T cells demonstrate high function in vitro and and in vivo. Longitudinal in vivo pharmacokinetic profiling of adoptively transferred polyclonal CAR-γδ T cells uncover subset-specific responses to IL-15 cytokine armoring and multiplex base editing. Our results present a robust platform for genetic modification of polyclonal CAR-γδ T cells and present unique opportunities to further define synergy and the contribution of discrete, engineered CAR-γδ T cell subsets to therapeutic efficacy in vivo .

Improving the Bioactivity and Antibiofilm Properties of Metallic Implant Materials via Controlled Surface Microdeformation.

Although metallic implants provide most of the required properties for bone-related applications, especially orthopedic implants, insufficient osseointegration, which may lead to loosening of the implant or prolonged healing time, is still an issue to be resolved. Osseointegration can be improved via application of various surface treatments on the metal surface. The current study focuses on a novel surface microdeformation method, which enables the formation of controlled surface patterns of various parameters. With this purpose, a surface microdeformation procedure was applied on 316L stainless steel surfaces, forming four different patterns which affected various surface parameters such as roughness, surface energy, dislocation activities close to the surface, and wettability. Static immersion tests in a simulated body fluid (SBF) environment showed that modifying the surface parameters via controlled surface patterning promoted the formation of a stable oxide layer and calcium-phosphate (CaP) deposition on the metal surfaces, improving bioactivity. Moreover, the higher amount of CaP deposition and oxide layer formation on the modified surfaces led to reduced ion release, which contributed to improved corrosion resistance. Finally, the effect of the formed surface patterns on antibiofilm formation was investigated via incubation with C. albicans for 24 h, which exhibited that microdeformation patterns remarkably inhibited the biofilm formation. Throughout the experiments, certain patterns yielded outstanding results among the four patterns formed. Overall, it was concluded that forming controlled patterns on stainless steel surfaces via surface microdeformation significantly contributed to the metal's biocompatibility via improving bioactivity, corrosion resistance, and antibiofilm formation properties. Especially, the specific surface properties such as increased surface energy, high surface roughness, and dislocation density close to the metal surface as well as increased hydrophilicity obtained via forming the pattern with relatively deeper and narrowly spaced indents yielded the most promising outcomes. These methodologies constitute novel approaches to be used while designing new methodologies for the surface modification of metallic implant materials for improved osseointegration.

Utilizing engineered extracellular vesicles as delivery vectors in the management of ischemic stroke: a special outlook on mitochondrial delivery.

Ischemic stroke is a secondary cause of mortality worldwide, imposing considerable medical and economic burdens on society. Extracellular vesicles, serving as natural nano-carriers for drug delivery, exhibit excellent biocompatibility in vivo and have significant advantages in the management of ischemic stroke. However, the uncertain distribution and rapid clearance of extracellular vesicles impede their delivery efficiency. By utilizing membrane decoration or by encapsulating therapeutic cargo within extracellular vesicles, their delivery efficacy may be greatly improved. Furthermore, previous studies have indicated that microvesicles, a subset of large-sized extracellular vesicles, can transport mitochondria to neighboring cells, thereby aiding in the restoration of mitochondrial function post-ischemic stroke. Small extracellular vesicles have also demonstrated the capability to transfer mitochondrial components, such as proteins or deoxyribonucleic acid, or their sub-components, for extracellular vesicle-based ischemic stroke therapy. In this review, we undertake a comparative analysis of the isolation techniques employed for extracellular vesicles and present an overview of the current dominant extracellular vesicle modification methodologies. Given the complex facets of treating ischemic stroke, we also delineate various extracellular vesicle modification approaches which are suited to different facets of the treatment process. Moreover, given the burgeoning interest in mitochondrial delivery, we delved into the feasibility and existing research findings on the transportation of mitochondrial fractions or intact mitochondria through small extracellular vesicles and microvesicles to offer a fresh perspective on ischemic stroke therapy.

A Brief Review of Surface Modification of Carbonyl Iron Powders (CIPs) for Magnetorheological Fluid Applications

Magnetorheological fluids (MRFs) is a smart fluid system that exhibits swift and reversible alterations in their rheological characteristics when exposed to an external magnetic field. MRFs are used for applications in various areas, including automotive systems, robotics, aerospace, and civil engineering. The performance of MRFs depends on the behavior of the dispersed magnetic particles, necessitating thoughtful consideration of particle traits to optimize fluid performance. Carbonyl Iron Powders (CIPs), high purity iron (>98%) reduced from penta carbonyl iron, are widely employed in MRFs due to their exceptional magnetic characteristics. Nevertheless, the innate surfaces of CIPs tend to conglomerate, leading to compromises in fluid stability and rheological performance. To overcome the challenges, an intensive research has been devoted to advancing surface modification techniques that augment the dispersion, stability, and overall functionality of MRFs based on CIPs. This review describes the comprehensive approach to surface modification of CIPs for highly stable MRFs. We discuss the various surface modification methodologies that have been explored to optimize the behavior of carbonyl iron-based MRFs. Coating techniques, surfactant functionalization, magnetic coatings, and emerging approaches such as nanocoatings and electrochemical modification are also summarized. Moreover, insights into potential applications and future prospects of these modified MRFs are provided.

Advances in Electrochemical Energy Storage over Metallic Bismuth-Based Materials.

Bismuth (Bi) has been prompted many investigations into the development of next-generation energy storage systems on account of its unique physicochemical properties. Although there are still some challenges, the application of metallic Bi-based materials in the field of energy storage still has good prospects. Herein, we systematically review the application and development of metallic Bi-based anode in lithium ion batteries and beyond-lithium ion batteries. The reaction mechanism, modification methodologies and their relationship with electrochemical performance are discussed in detail. Additionally, owing to the unique physicochemical properties of Bi and Bi-based alloys, some innovative investigations of metallic Bi-based materials in alkali metal anode modification and sulfur cathodes are systematically summarized for the first time. Following the obtained insights, the main unsolved challenges and research directions are pointed out on the research trend and potential applications of the Bi-based materials in various energy storage fields in the future.

Investigating the impact of plasma nitriding on Ti6Al4V surface, structural, and mechanical properties and their simultaneous evaluation via laser opto-ultrasonic dual detection (LOUD) approach

Titanium alloys possess exceptional properties, but due to their poor surface characteristics, several engineering processes have been developed to modify surface properties. Surface modification methodologies such as plasma nitriding exhibit a favourable pathway to improve these properties. This study investigates the impact of plasma nitriding on surface properties and their evaluation via the laser opto-ultrasonic dual detection (LOUD) technique. The scanning electron microscope, X-ray diffraction, and tensile testing results showed that with the increase in nitride plasma power density from 1.42 to 10.0 × 102 W/cm2, a substantial variation in microstructure and phase transformation occurs, eventually refining the grain size, increasing the hardness from 310.83-HV5.0 to 745.50-HV5.0 and elastic modulus (E) from 115.26 to 128.35 GPa, respectively. Furthermore, these characteristics were assessed concurrently through ultrasonic and optical signal processing for LOUD detection. The results of G.S and E from the acoustic attenuation coefficient and longitudinal and shear wave velocities are reliable with the results of conventional optical microscopy and tensile testing with (R2 ≥ 0.996). Meanwhile, the optical spectral data were analyzed to determine the hardness. The results showed that the calibration curve of the intensity ratios (Ti-II/Ti-I) and plasma electron temperature exhibited a linear relationship with hardness (R2 ≥ 0.989), which showed a good approximation.

Bamboo-derived adsorbents for environmental remediation: A review of recent progress

The bamboo family of plants is one of the fastest-growing species in the world. As such, there is an abundance of bamboo residues available for exploitation, especially in southeast Asian, central African and south American regions. The preparation of efficient adsorbents from bamboo residues is an emerging exploitation pathway. Biochars, activated carbons or raw bamboo fibers embedded with nanoparticles, each class of materials has been shown to be highly efficient in adsorption processes. This review aims to summarize recent findings in the application of bamboo-based adsorbents in the removal of organic, inorganic, or gaseous pollutants. Therefore, this review first discusses the preparation methods and surface modification methodologies and their effects on the adsorbent elemental content and other basic properties. The following sections assess the recent progress in the adsorption of heavy metals, organics, and gaseous substances by bamboo-based adsorbents, focusing on the optimum adsorption capacities, adsorption mechanisms and the optimum-fitting kinetic models and isotherms. Finally, research gaps were identified and directions for future research are proposed.

Plasma Surface Engineering of Natural and Sustainable Polymeric Derivatives and Their Potential Applications.

Recently, natural as well as synthetic polymers have been receiving significant attention as candidates to replace non-renewable materials. With the exponential developments in the world each day, the collateral damage to the environment is incessant. Increased demands for reducing pollution and energy consumption are the driving force behind the research related to surface-modified natural fibers (NFs), polymers, and various derivatives of them such as natural-fiber-reinforced polymer composites. Natural fibers have received special attention for industrial applications due to their favorable characteristics, such as low cost, abundance, light weight, and biodegradable nature. Even though NFs offer many potential applications, they still face some challenges in terms of durability, strength, and processing. Many of these have been addressed by various surface modification methodologies and compositing with polymers. Among different surface treatment strategies, low-temperature plasma (LTP) surface treatment has recently received special attention for tailoring surface properties of different materials, including NFs and synthetic polymers, without affecting any of the bulk properties of these materials. Hence, it is very important to get an overview of the latest developments in this field. The present article attempts to give an overview of different materials such as NFs, synthetic polymers, and composites. Special attention was placed on the low-temperature plasma-based surface engineering of these materials for diverse applications, which include but are not limited to environmental remediation, packaging, biomedical devices, and sensor development.

Polyol recognition in catalysis: toward selective modification of glycosylated polypeptides with boronic acid-rhodium(II) catalysts.

Proximity-induced methodologies for peptide and protein modification have been developed using recognition elements like inhibitors, antibodies, or affinity tags on amino acids. However, the recognition of saccharides for chemical modification remains widely unexplored. Studies exploring boronic acids and their derivatives have shown their alluring capabilities as selective molecular recognition elements for saccharides, and in this study we describe the application of these ideas to the discovery of a catalytic proximity-induced methodology for covalent modification of glycopeptides using boronic acids as a saccharide recognition element.

Tuning foreign body response with tailor-engineered nanoscale surface modifications: fundamentals to clinical applications.

Biomaterials are omnipresent in today's healthcare services and are employed in various applications, including implants, sensors, healthcare accessories, and drug delivery systems. Unfavorable host immunological responses frequently jeopardize the efficacy of biomaterials. As a result, surface modification has received much attention in controlling inflammatory responses since it helps camouflage the biomaterial from the host immune system, influencing the foreign body response (FBR) from protein adsorption to fibrous capsule formation. Surfaces with controlled nanotopography and chemistry, among other surface modification methodologies, have effectively altered the immune response to biomaterials. However, the field is still in its early stages, with only a few studies showing a synergistic effect of surface chemistry and nanotopography on inflammatory and wound healing pathways. Therefore, this review will concentrate on the individual and synergistic effects of surface chemistry and nanotopography on FBR modulation and the molecular processes known to modulate these responses. This review will also provide insights into crucial research gaps and advancements in various tactics for modulating FBR, opening new paths for future research. This will further aid in improving our understanding of the immune response to biomaterials, developing advanced surface modification techniques, designing immunomodulatory biomaterials, and translating discoveries into clinical applications.

Thia-Michael addition: the route to promising opportunities for fast and cysteine-specific modification.

Over the last few decades, design and discovery of chemical reactions that enable modification of proteins at pre-determined sites have been the focus of synthetic organic chemists. As an invaluable tool, the site-and chemoselective functionalization of peptides and proteins offers an exciting opportunity for creating high-value multicomponent conjugates with diverse applications in life sciences and pharmacology. In recent years, multiple strategies have emerged that target natural amino acids directly or convert them into other reactive species for further ligations. However, reactivity and selectivity are still key issues in the current state of chemical modification methodologies. Cysteine is one of the least abundant amino acids and exhibits unique chemistry of the thiol or thiolate group which makes it susceptible to a series of post-translational modifications. The thia-Michael "click" addition reactions, which can proceed under facile conditions provide a promising way for thiol-selective modification of cysteine-containing proteins. In this review, we summarize various reactions for cysteine-selective peptide and protein modification, focus on thia-Michael "click" addition reactions, elaborate on their historical perspective and mechanism, and highlight their applications in modifying biomolecules in a site-specific way.

Ink-Drop Dynamics on Chemically Modified Surfaces

Inkjet printing provides an efficient routine for distributing functional materials into locations with well-designed arrangements. As one of the most critical factors in determining the printing quality, the impacting and depositing behaviors of ink drops largely depend on the wettability of the target surface. In addition to printing on solids with intrinsic wettability, various ink-drop impact dynamics and deposition morphologies have been reported through modifying the surface wettability including both homogeneous and heterogeneous, which opens up possibilities for applications such as advanced optic/electric device fabrication and highly sensitive detection. In this Perspective, we summarize recent progress in the modification methods of solid surface wettability and their capability in modulating the ink-drop impacting and depositing dynamics. The challenges facing ink-drop regulation by chemical modification methodologies are also envisaged at the end of the Perspective.

A Comprehensive Review on Advances in TiO2 Nanotube (TNT)-Based Photocatalytic CO2 Reduction to Value-Added Products

The photocatalytic reduction of CO2 into solar fuels by using semiconductor photocatalysts is one of the most promising approaches in terms of pollution control as well as renewable energy sources. One of the crucial challenges for the 21st century is the development of potential photocatalysts and techniques to improve CO2 photoreduction efficiency. TiO2 nanotubes (TNTs) have recently attracted a great deal of research attention for their potential to convert CO2 into useful compounds. Researchers are concentrating more on CO2 reduction due to the rising trend in CO2 emissions and are striving to improve the rate of CO2 photoreduction by modifying TNTs with the appropriate configuration. In order to portray the potential applications of TNTs, it is imperative to critically evaluate recent developments in synthesis and modification methodologies and their capability to transform CO2 into value-added chemicals. The current review provides an insightful understanding of TNT production methods, surface modification strategies used to enhance CO2 photoreduction, and major findings from previous research, thereby revealing research gaps and upcoming challenges. Stability, reusability, and the improved performance of TNT photocatalysts under visible light as well as the selection of optimized modification methods are the identified barriers for CO2 photoreduction into valuable products. Higher rates of efficacy and product yield can be attained by synthesizing suitable photocatalysts with addressing the limitations of TNTs and designing an optimized photoreactor in terms of the proper utilization of photocatalysts, incident lights, and the partial pressure of reactants.

Bioprocess Engineering, Transcriptome, and Intermediate Metabolite Analysis of L-Serine High-Yielding Escherichia coli W3110.

L-serine is widely used in the food, cosmetic, and pharmaceutical industries. However, the complicated metabolic network and regulatory mechanism of L-serine production lead to the suboptimal productivity of the direct fermentation of L-serine and limits its large-scale industrial production. In this study, a high-yield L-serine production Escherichia coli strain was constructed by a series of defined genetic modification methodologies. First, L-serine-mediated feedback inhibition was removed and L-serine biosynthetic pathway genes (serAfr, serC, and serB) associated with phosphoglycerate kinase (pgk) were overexpressed. Second, the L-serine conversion pathway was further examined by introducing a glyA mutation (K229G) and deleting other degrading enzymes based on the deletion of initial sdaA. Finally, the L-serine transport system was rationally engineered to reduce uptake and accelerate L-serine export. The optimally engineered strain produced 35 g/L L-serine with a productivity of 0.98 g/L/h and a yield of 0.42 g/g glucose in a 5-L fermenter, the highest productivity and yield of L-serine from glucose reported to date. Furthermore, transcriptome and intermediate metabolite of the high-yield L-serine production Escherichia coli strain were analyzed. The results demonstrated the regulatory mechanism of L-serine production is delicate, and that combined metabolic and bioprocess engineering strategies for L-serine producing strains can improve the productivity and yield.

Piezoelectric charge induced hydrophilic poly(L-lactic acid) nanofiber for electro-topographical stimulation enabling stem cell differentiation and expansion

Cell-traction driven electrical stimulation on piezoelectric nanofibers mediates cell behavior without chemical factors or external stimuli, indicating a promising therapy at cell level. Generally, surface modification is required to achieve favorable cell adhesion for efficient electromechanical signal transmission. Nevertheless, common modification methodologies either easily fade away or destroy the nanostructure of piezoelectric nanofibers. Herein, with the assistance of ultrasound activated surface charges, in situ hydrophilic modification on piezoelectric poly(L-lactic acid) nanofibers is first proposed for cell adhesion. Due to the electrostatic interaction between dopamine and activated piezoelectric nanofiber, the efficient and robust in situ modification is obtained without compromising the nanofibrous structure. Stimulated by the piezoelectric nanofibers with modification, neural stem cells differentiate significantly into nerve cells on day 7 without exogenous growth factors. To our knowledge, the effect of inducing stem cell differentiation far outperforms that in previous reports. In addition, it has been demonstrated that the level of both cell differentiation and directional expansion is consistent with that of cell adhesion condition regardless of the intensity of electrical cue. This connection of cell adhesion and electro-topographical stimulation effects may guide the efforts in the design of electroactive scaffolds.

Covalent modification of poly(vinyl chloride) via organometallic Barbier reaction

The development of efficient synthetic methodologies for chemical functionalization and modification of existing polymers to improve or diversify the physicochemical and mechanical properties is an ongoing quest in macromolecular science. This is especially true for the generation of polymeric materials out of commercial/commodity polymers via structural tailoring since these polymers are produced in vast quantities and are structurally diverse. In this study, we report on benign chemical modification of an important commercial polymer, poly(vinyl chloride) (PVC) via Barbier reaction. The methodology is based on the employment of magnesium metal to generate nucleophilic alkyl-magnesium chloride groups on polymer backbone and addition of these nucleophilic centers to electrophilic carbonyl groups. The synthetic procedure can be implemented in a one-pot fashion by utilizing commonly available aldehyde or epoxide bearing compounds along with elemental magnesium. The Barbier addition of PVC backbone generated alkyl-magnesium chloride groups on the model aldehyde substrates with different structures were achieved with > 84 % functionalization degrees. It was shown that the functionalization degrees can easily be regulated by the simple alteration of employed magnesium ratio to backbone present alkyl chloride groups. Functionalization studies were investigated via 1H NMR, FT-IR and SEC analyses as well as contact angle measurements. Considering the wide industrial/ research utilization of poly(vinyl chloride) together with commercial availability, abundant reactive alkyl chloride bonds in backbone chains of this polymer offer easy to implement structural tailoring via proposed organometallic Barbier reaction.

A chemoenzymatic strategy for site-selective functionalization of native peptides and proteins.

The emergence of new therapeutic modalities requires complementary tools for their efficient syntheses. Availability of methodologies for site-selective modification of biomolecules remains a long-standing challenge, given the inherent complexity and the presence of repeating residues that bear functional groups with similar reactivity profiles. We describe a bioconjugation strategy for modification of native peptides relying on high site selectivity conveyed by enzymes. We engineered penicillin G acylases to distinguish among free amino moieties of insulin (two at amino termini and an internal lysine) and manipulate cleavable phenylacetamide groups in a programmable manner to form protected insulin derivatives. This enables selective and specific chemical ligation to synthesize homogeneous bioconjugates, improving yield and purity compared to the existing methods, and generally opens avenues in the functionalization of native proteins to access biological probes or drugs.

Physical characterization and biological tests of bioactive titanium surfaces prepared by short-time micro-arc oxidation in green electrolyte

Titanium (Ti) and its alloys are the most used biomaterials in dental and orthopedic implant applications. However, despite the good performance of these materials, implants may fail; therefore, several surface modification methodologies have been developed to increase the bioactivity of the metal surface, accelerating the osseointegration process while promoting improved corrosion performance. In this work, the production of a TiO2 coating on titanium through a short-time micro-arc oxidation (MAO) in a green electrolyte (obtained by a mixed solution of K3PO4 and Ca(CH3COO)2.H2O) is proposed, aiming at obtaining a porous oxide layer with Ca and P incorporation through an environmentally friendly experimental condition. The morphology, chemical composition, crystalline structure, wettability, hardness and bioactivity of the modified Ti surfaces were characterized. The MAO process at 250 V for 1 min in the green electrolyte solution allowed the production of a highly porous oxide surface in the anatase crystalline phase, with effective Ca and P incorporation. Pre-osteoblastic cells were used in in-vitro assays to analyze viability, adhesion, proliferation and ability to perform extracellular matrix mineralization on the Ti surfaces (polished and MAO-treated Ti). The MAO-treated Ti surface exhibited better results in the bioactivity tests, presenting more calcium phosphate precipitates. This surface also presented higher hardness, lower hydrophilicity and better performance in biological tests than the polished surface. The here-reported MAO-treated Ti surface is promising for dental implants, especially in patients having poor bone quality that requires greater stimulation for osteogenesis.

Surface Modification of 6xxx Series Aluminum Alloys

Due to their superior mechanical properties, formability, corrosion resistance, and lightweight nature, 6xxx series aluminum (Al) alloys are considered as a promising structural material. Nevertheless, the successful application of these materials depends on their response to the external environment. Recently, designers considered the surface properties an equally important aspect of the component design. Due to this concern, these alloys are subjected to varieties of surface modification methodologies. Many methodologies are explored to modify the 6xxx series Al alloys surfaces effectively. These methods are anodizing, plasma electrolytic oxidation (PEO), cladding, friction stir processing, friction surfacing, melting, alloying, and resolidification using high energy beams, etc. This review work discusses some of these methods, recent research activities on them, important process variables, and their role on the final properties of the surfaces.

DNA-assisted site-selective protein modification.

Protein modification is important for various types of biomedical research, including proteomics and therapeutics. Many methodologies for protein modification exist, but not all possess the required level of efficiency and site selectivity. This review focuses on the use of DNA to achieve the desired conversions and levels of accuracy in protein modification by using DNA (i) as a template to help concentrate dilute reactants, (ii) as a guidance system to achieve selectivity by binding specific proteins, and (iii) even as catalytic entity or construct to enhance protein modification reactions.