Functionalization Of NPs Research Articles

Advances in the use of nanomaterials in tumour therapy

Cancer is one of the most common causes of death. It is indeed vital to develop advanced treatments against severe cancers. Traditional therapies like surgery may not clear the tumour cells completely, which will lead to cancer recurrence. The possibility of normal cells being killed cannot be excluded in chemotherapy, which is one of the most popular ways to treat cancer—using nanomaterials (NPs) as drug carriers can somewhat avoid these problems. And they are widely used in targeted therapies to treat cancer. The essay first introduces several types of biopolymeric NPs, such as liposomes, polymeric nanoparticles and inorganic particles. Mechanisms of treatments using NPs are included. For polymeric nanoparticles, dendrimers, polymeric micelles and gels are included. Reasons why inorganic NPs, including mesoporous silica NPs and metallic oxides, are used in treatment are then explained. Then, the functions of different NPs of the same type are compared. Finally, other studies about each specific NP are introduced. This article is significant for future studies on drug carriers for cancer treatment.

Bio-inspired synthesis of Ag-g-C3N4 nanocomposites and their application for photocatalytic degradation of para-nitrophenol

Nanocomposites are promising in advanced materials for environmental applications due to their ability to boost functionality through synergistic effects. Graphitic carbon nitride (g-C3N4) is renowned for its exceptional characteristics in photocatalysis. This work examines the preparation of g-C3N4 from different precursors, and how the presence of silver nanoparticles (Ag NPs) and silver ions (Ag+) in g-C3N4 matrices improve their combined effect on photocatalytic activity, specifically in the degradation of para-nitrophenol (PNP), a persistent organic pollutant. From urea and melamine precursors for the preparation of g-C3N4, the latter provided a much higher yield. Using an easy synthesis approach, Ag NPs were evenly distributed in the g-C3N4 framework, whereas Ag+ ions were incorporated by an apparent physical procedure. A bio-inspired, environmentally friendly method was also applied to prepare Ag NPs. The nanocomposites showed improved light absorption and separation of charge carriers due to the synergistic interaction between g-C3N4 and Ag species. Using UV and Vis LED light sources, we investigated both pure g-C3N4 and Ag-g-C3N4 catalysts. For breaking down para-nitrophenol, the silver-modified catalysts performed significantly better than pure g-C3N4 in both UV and Vis. The study clarified the functions of Ag NPs and Ag+ ions in enhancing photocatalytic activity by examining their involvement in generating reactive oxygen species and degrading pollutants. This work highlights the capability of g-C3N4-based nanocomposites as effective photocatalysts for environmental remediation. It also explores the benefits of adding silver species to improve performance in degrading pollutants.

Valorization of Vaccinium corymbosum waste from the extraction of bioactive compounds: Nanoparticles synthesis and applications

This study presents the biogenic synthesis of silver nanoparticles (Ag NPs), zinc oxide nanoparticles (ZnO NPs), and iron oxide nanoparticles (FeO NPs) using V. corymbosum extracts as a reducing agent, varying the ultrasound extraction times (t1 = 20 min, t2 = 15 min, t3 = 10 min). Ag NPs exhibited an antimicrobial efficiency of 98.2 %, being most effective with t2 due to their smaller size. ZnO NPs demonstrated the best thermal stability with t1, and FeO NPs showed optimal magnetic properties with t3. The reduction of methylene blue by ZnO and FeO NPs was significant, with ZnO-t1 and FeO-t3 standing out. The nanoparticles exhibited distinctive optical characteristics and adequate morphology, depending on the extraction time. This work highlights the feasibility of using natural extracts to synthesize nanoparticles, promoting sustainable methods in nanoscience and nanotechnology. Future research should focus on the functionalization of NPs to expand their applications.

Repair spinal cord injury with a versatile anti-oxidant and neural regenerative nanoplatform

Spinal cord injury (SCI) often results in motor and sensory deficits, or even paralysis. Due to the role of the cascade reaction, the effect of excessive reactive oxygen species (ROS) in the early and middle stages of SCI severely damage neurons, and most antioxidants cannot consistently eliminate ROS at non-toxic doses, which leads to a huge compromise in antioxidant treatment of SCI. Selenium nanoparticles (SeNPs) have excellent ROS scavenging bioactivity, but the toxicity control problem limits the therapeutic window. Here, we propose a synergistic therapeutic strategy of SeNPs encapsulated by ZIF-8 (SeNPs@ZIF-8) to obtain synergistic ROS scavenging activity. Three different spatial structures of SeNPs@ZIF-8 were synthesized and coated with ferrostatin-1, a ferroptosis inhibitor (FSZ NPs), to achieve enhanced anti-oxidant and anti-ferroptosis activity without toxicity. FSZ NPs promoted the maintenance of mitochondrial homeostasis, thereby regulating the expression of inflammatory factors and promoting the polarization of macrophages into M2 phenotype. In addition, the FSZ NPs presented strong abilities to promote neuronal maturation and axon growth through activating the WNT4-dependent pathways, while prevented glial scar formation. The current study demonstrates the powerful and versatile bioactive functions of FSZ NPs for SCI treatment and offers inspiration for other neural injury diseases.

Dual functionalization of polyamide reverse osmosis thin film composite membrane for improving chlorine resistance

Contemporary high-efficiency polyamide (PA) membranes are constructed using aliphatic or aromatic amines combined with acyl chlorides. Nevertheless, the aromatic rings attached to the N–H group within the amide linkages are vulnerable to degradation by chlorine. The surface of a PA reverse osmosis (RO) membrane was altered in this work through the dual functionalization of tannic acid (TA) and silver nanoparticles (Ag NPs) to improve separation performance, chlorine resistance, and anti-bacterial capabilities of membranes. This study provides an insight in the role and synergistic effects of TA and Ag NPs for enhancing the chlorine resistance of the modified TFC membranes. The outcome indicated that the RO-TA/Ag modified membrane exhibited the maximum rejection of 98.31%, slightly surpassing the pristine RO membrane, which had a rejection rate of 96.52%. The RO-TA/Ag modified membrane also shown improved chlorine tolerance against 500 ppm sodium hypochlorite solution (NaClO), as evidenced by X-ray photoelectron spectroscopy (XPS) measurement which revealed reduced chlorine content in contrast to pristine RO and RO-TA membrane. The RO-TA/Ag membrane exhibited the largest inhibitory zone for both Gram-positive, S. aureus and Gram-negative, E. coli bacteria. The synergistic effects of the dual functionalization of TA and Ag NPs which render the modified membrane with high anti-chlorine and anti-bacterial capabilities are discussed.

A photothermal colorimetric dual-signal sensor for Staphylococcus aureus in food based on CuS nanoparticles

Staphylococcus aureus (S. aureus) is a common foodborne pathogenic organism, and rapid detection with high sensitivity and targeted killing are essential for controlling its spread. Therefore, a sandwich structure of magnetic bead-target bacteria-copper sulfide was constructed in this paper. The photothermal conversion function and peroxidase (POD) activity of CuS NPs were utilized to establish a dual sensing platform for temperature and color rendering, that is, after capturing target bacteria, light was converted to heat signal by infrared irradiation. Moreover, the specific detection of S. aureus was realized by detecting the temperature change of the complex and the oxidation of TMB by nano-enzymes of residual CuS in the supernatant to form oxTMB blue product, which formed the change of UV (ultraviolet) − Visible spectroscopy. Based on the high specificity binding and strong signal amplification of the method, the linear range of the photothermal specific probe combined with MBs-S. aureus-CuS was 10–106 CFU/mL, and the detection limit was 1.407 CFU/mL. The linear range of the color specific probe was 10–106 CFU/mL, R2 = 0.9853, and the detection limit was 1.15 CFU/mL. The photothermal efficiency of MBs-S. aureus-CuS system can reach 62.84 %, which has excellent photothermal conversion effect, and the temperature rises to about 70 °C within 7 min, which can directly kill bacteria in the detection. In addition, the portable infrared thermal imager is applied to realize the real-time field detection of S. aureus. The study was significant, because exploratory experiments were conducted to conceive a proof-of-concept based on multiple bacterial sensors that could easily be adapted to a variety of fields where bacteria pose a threat.

Green Synthesis of Selenium Nanoparticles: Characterization and Therapeutic Applications in Microbial and Cancer Treatments

Selenium is one of these micronutrients that are essential for animals, plants and microorganisms to remain functional. This review is about the green synthesis of selenium nanoparticles and its application in microbial and cancer therapies. Our hypothesis was that Se NPs produced using plant extracts might offer the biocompatibility and environmental friendliness advantages, and hence be a new prospect for medical applications. To test our hypothesis, we conducted a comprehensive analysis of recent literature, exploring various green synthesis conditions and processes for Se NPs. Various characterisation techniques such as spectroscopy, microscopy and physicochemistry were discussed in order to provide insight into the formation and function of green-synthesised Se NPs. Our findings show that Se NPs produced by green chemistry methods have good properties such as uniform size, shape and stability as detailed examples from recent studies reveal. Furthermore, we discussed the therapeutic and theranostic applications of Se NPs produced in this manner: their potential in antimicrobial and anticancer treatments. Through illustrations of cases where Se NPs inhibit microbial growth and cause apoptosis in cancer cells, the practical significance of our findings was underscored. In summary, our review affirms that using green-mediated synthesis Se NPs improves their biocompatibility and therapeutic efficacy, thus opening up new realms for their application in medical research.

Lactosylated lipid calcium phosphate-based nanoparticles: A promising approach for efficient DNA delivery to hepatocytes.

For safe and effective gene therapy, the ability to deliver the therapeutic nucleic acid to the target sites is crucial. In this study, lactosylated lipid phosphate calcium nanoparticles (lac-LCP) were developed for targeted delivery of pDNA to the hepatocyte cells. The lac-LCP formulation contained lactose-modified cholesterol (CHL), a ligand that binds to the asialoglycoprotein receptor (ASGR) expressed on hepatocytes, and polyethyleneimine (PEI) in the core. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) were used to monitor the chemical modification, and the physicochemical properties of NPs were studied using dynamic light scattering (DLS) and transmission electron microscopy (TEM). To evaluate transfection efficiency, cellular uptake and GFP expression were assessed using fluorescence microscopy and flow cytometry. The results revealed that lactose-targeted particles (lac-LCP) had a significant increase in cellular uptake by hepatocytes. The inclusion of a low molecular weight PEI (1.8 KDa) with a low PEI/pDNA ratio of 1 in the core of LCP, elicited high degrees of GFP protein expression (by 5 and 6-fold), which exhibited significantly higher efficiency than PEI 1.8 KDa and Lipofectamine. The successful functionalization and nuclear delivery of LCP NPs described here indicate its promise as an efficient delivery vector to hepatocyte nuclei.

Manganese-based nanomaterials promote synergistic photo-immunotherapy: green synthesis, underlying mechanisms, and multiple applications.

Single phototherapy and immunotherapy have individually made great achievements in tumor treatment. However, monotherapy has difficulty in balancing accuracy and efficiency. Combining phototherapy with immunotherapy can realize the growth inhibition of distal metastatic tumors and enable the remote monitoring of tumor treatment. The development of nanomaterials with photo-responsiveness and anti-tumor immunity activation ability is crucial for achieving photo-immunotherapy. As immune adjuvants, photosensitizers and photothermal agents, manganese-based nanoparticles (Mn-based NPs) have become a research hotspot owing to their multiple ways of anti-tumor immunity regulation, photothermal conversion and multimodal imaging. However, systematic studies on the synergistic photo-immunotherapy applications of Mn-based NPs are still limited; especially, the green synthesis and mechanism of Mn-based NPs applied in immunotherapy are rarely comprehensively discussed. In this review, the synthesis strategies and function of Mn-based NPs in immunotherapy are first introduced. Next, the different mechanisms and leading applications of Mn-based NPs in immunotherapy are reviewed. In addition, the advantages of Mn-based NPs in synergistic photo-immunotherapy are highlighted. Finally, the challenges and research focus of Mn-based NPs in combination therapy are discussed, which might provide guidance for future personalized cancer therapy.

Ultrasensitive fluorometric determination of aluminum using the CoFe2O4 NPs/SDS/oxine system with the aid of ultrasound waves.

In this study, we present a thoughtful integration of a dispersive solid-phase sorbent and oxine for the ultrasensitive and highly selective determination of Al3+ ions. Cobalt ferrite nanoparticles (CoFe2O4 NPs) modified with oxine were employed to facilitate the pre-concentration and estimation of Al3+, forming highly fluorescent chelate. The modification process included the assistance of sodium dodecyl sulfate (SDS) and sonication. The results indicated that the fluorescence intensity of Al3+-oxine/SDS@CoFe2O4 NPs surpassed that of Al3+-oxine alone. The confirmation of the successful functionalization of CoFe2O4 NPs with oxine was established through various techniques. Under optimal conditions, the fluorescence intensity exhibited a positive correlation with increasing concentrations of Al3+ within the range of 0.029-600 ng mL-1, achieving a detection limit of 0.0087 ng mL-1 based on signal to noise ratio 3 : 1. The developed method was effectively applied to the determination of Al3+ in drinking water samples, yielding recoveries in the range of 97.19% to 103.13%, with a relative standard deviation (RSD%) not exceeding 3.78%.

Stability of binary colloidal mixtures of Au noble metal and ZnS semiconductor nanoparticles

Controlling the stability of colloidal nanoparticles in multicomponent systems, i.e., mixtures of colloids, is of vital importance for product formulations and separation processes of nanoparticles. However, very few studies are currently found in literature regarding the generation of binary colloids by mixing of colloidal nanoparticles, particularly small nanoparticles (< 20 nm). In this study, we report on the development of a stable binary colloid made of nanoparticles of different sizes and compositions. As a model system for this study, we mixed aqueous dispersions of gold nanoparticles (Au NPs) and ZnS quantum dots (QDs). We investigated the stability of Au NPs with three different surface ligands after mixing them with ZnS QDs, both before and after functionalization of the Au NPs with bis(p-sulfonatophenyl) phenylphosphine (BSPP). We used UV–visible spectroscopy as the primary method to monitor stability of nanoparticles in the binary mixture over time. We found out that the released thioglycerol and acetate from the surface of ZnS QDs to the binary mixture induces agglomeration in Au NPs. The surface chemistry and the purification process of Au NPs after their synthesis and surface treatment were identified as key parameters to regulate the stability in the mixture. Thus, we successfully achieved a stable mixture of BSPP-functionalized Au NPs with ZnS QDs as a model of a stable binary mixture. We believe that this study is important to stimulate research directed towards real-world multicomponent formulations including their characterization and the understanding of surface interactions.

Influence of microstructure on dielectric function and plasmonic properties of silver nanoparticles grown by solid state dewetting: a spectroscopic ellipsometry study

This work reports the microstructure influence on dielectric function and plasmonic properties of silver nanoparticles (Ag NPs). Ag NPs with varying microstructures were grown on corning glass substrate by solid-state dewetting (SSD) of sputtered silver thin films deposited by varying RF power. Dielectric function and plasmonic properties of Ag NPs were investigated from spectroscopic ellipsometry (SE) data using a quite unique model in terms of the combination of different oscillators. Drude–Lorentz model along with two Gauss oscillators was used to account for intraband, interband transitions and different modes of localized surface plasmon resonance (LSPR) of Ag NPs. It was observed that peak of imaginary part of pseudo dielectric function, which is due to LSPR of Ag NPs, shifted towards the lower energy at higher RF power due to increase in thickness of precursor films which subsequently resulted in to increase in particle size. A shift in the LSPR peak in absorbance spectra in UV–Vis-NIR spectroscopy was also observed. No LSPR peak is observed in SE or UV–Vis absorbance spectra for thick films deposited at high RF power due to the presence of continuous silver film even after annealing. This change in microstructure from nanoparticle formation to continuous films is also reflected in the values of void fraction and surface roughness calculated from SE using Bruggeman Effective Medium Approximation (BEMA). Field Emission Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), and X-ray diffraction (XRD) were used to probe the microstructure of Ag NPs. Root mean square (RMS) roughness evaluated from AFM matched well with surface roughness measured from SE.

An In vivo Investigation of Ascorbic Acid Tethered Polymeric Nanoparticles for Effectual Brain Transport of Rivastigmine.

The goal of this study was to see if ascorbic acid grafted polylactic glycolic acid-b-polyethylene glycol nanoparticles (PLGA-b-PEG NPs) might boost the carrying or transport capacity of rivastigmine(RSM) to the brain via choroid plexus Sodium-dependent vitamin C transporter 2 (SVCT2 transporters). The IR and 1H NMR, were used to characterise the PLGA-b-PEG copolymer. Nanoprecipitation method was used to make PLGA-b-PEG NPs. To promote SVCT2- mediated transportation of ascorbic acid (Asc) into the brain, PLGA-b-PEG NPs of acceptable size, polydispersity, and drug loading were bound with ascorbic acid (PLGA-b-PEG-Asc). When compared to PLGA-b-mPEG NPs, the surface functionalization of NPs with ascorbic acid dramatically improved the cellular uptake of NPs in SVCT2 expressing NIH/3T3 cells. Radial Arm Maze Test, and Acetylcholinesterase (AChE) activity in scopolamine-induced amnetic rats were used to assess in vivo pharmacodynamic effectiveness. In vivo pharmacodynamic tests revealed that drug loaded PLGA-b-PEG-Asc NPs had much greater therapeutic and sustained activity than free drugs, and PLGA-b-mPEG NPs to the brain. As a consequence, the findings revealed that using ascorbic acid grafted PLGA-b-PEG NPs to deliver bioactives to the brain is a potential strategy.

Collagen Biocomposites Derived from Fish Waste: Doped and Cross-Linked with Functionalized Fe3O4 Nanoparticles and Their Comparative Studies with a Green Approach.

Collagen-based nanobiocomposites can reabsorb and are biodegradable. These properties are effectively controlled by the number of cross-links. This study demonstrates an effortless and proficient approach for the functionalization of Fe3O4 NPs for cross-linking collagen obtained from biowaste, viz., fish scales of Lates Calcarifer, a marine origin. The size of Fe3O4 NPs (10-40 nm) was confirmed using particle size analysis. The physico-chemical properties of the aminosilane-coated Fe3O4 NPs cross-linked via succinylated collagen (FFCSC) were characterized using different analytical techniques and compared with succinylated collagen doped with Fe3O4 NPs (FDSC). Thermogravimetric analysis indicates cross-linked product FFCSC to be more stable than the FDSC. Also, the antibacterial effect was more pronounced for FFCSC than for FDSC nanobiocomposites. FFCSC exhibited improved mechanical properties which are essential for materials used for wound dressing purposes. Moreover, the cell viability of fibroblasts (3T3-L1) and their morphology studied by SEM and fluorescence microscopy showed biocompatibility of both FDSC and FFCSC. Thus, the current investigation, involves a waste to wealth approach where the collagen-based nanobiocomposites present an easy way to recycle the biowaste to value-added products using simple and clean methods, which are suitable for use in biomedical and environmental applications.

Cellulose nanocrystals doped silver nanoparticles immobilized agar gum for efficient photocatalytic degradation of malachite green

The present study involves the synthesis of green functional material based on the silver nanoparticle (Ag NPs) doped cellulose nanocrystals (CNC) immobilized agar gum (AA) biopolymer using chemical coprecipitation method. The stabilization of Ag NPs in cellulose matrix and functionalization of the synthesized material through agar gum was analyzed using various spectroscopic techniques such as Fourier Transform Infrared (FTIR), Scanning electron microscope (SEM), Energy X-Ray diffraction (EDX), Photoelectron X-ray (XPS), Transmission electron microscope (TEM), Selected area energy diffraction (SAED) and ultraviolet visible (UV–Vis) spectroscopy. The XRD results suggested that the synthesized AA-CNC@Ag BNC material is composed of 47 % crystalline and 53 % amorphous nature having distorted hexagonal structure due to capping of Ag NPs by amorphous biopolymer matrix. The Debye-Scherer crystallite sized was calculated as 18 nm which is found in close agreement with TEM analysis (19 nm). The SAED yellow fringes simulates the miller indices values with XRD patterns and supported the surface functionalization of Ag NPs by biopolymer blend of AA-CNC. The XPS data supported the presence of Ag0 as indexed by Ag3d orbital corresponding to Ag3d3/2 at 372.6 eV and Ag3d5/2 at 366.6 eV. The surface morphological results revealed a flaky surface of the resultant material having well distributed Ag NPs in the matrix. The EDX and atomic concentration results given by XPS supported the presence if C, O and Ag in the bionanocomposite material. The UV–Vis results suggested that the material is both UV and visible light active having multiple SPR effects with anisotropy. The material was explored as a photocatalyst for remediation of wastewater contaminated by malachite green (MG) using advance oxidation process (AOP). Photocatalytic experiments were performed in order to optimize various reaction parameters such as irradiation time, pH, catalyst dose and MG concentration. The obtained results showed that almost 98.85 % of MG was degraded by using 20 mg of catalyst at pH 9 for 60 min of irradiation. The trapping experiments revealed that •O2− radicals played primary role in MG degradation. This study will provide new possible strategies for the remediation of wastewater contaminated by MG.

Synthesis of functionalized α -Fe2O3 nanoparticles: Characterization and applications

In this study, EDTA functionalized α -Fe2O3 (Ferric Oxide) NPs were synthesized via chemical and green synthetic methods. FTIR spectra confirmed the functionalization of NPs with EDTA. X-ray diffraction confirmed the formation ‘α’ form of Fe2O3. UV–Vis diffuse reflectance spectra were applied to study the band gap of the NPs and was determined as 2.75 eV. MB and MG dyes were used as model dyes to study the adsorption and photocatalytic properties of NPs under visible and ultraviolet light radiation respectively. FESEM and HRTEM methods are used to study the morphology of the synthesized nanoparticles. Surface functionalization played a significant role in understanding the adsorption of dyes onto the surface of the photocatalyst. The crystallite size of chemical synthesized and green synthesized α- Fe2O3 was found to be 12 nm and 9 nm respectively. Maximum degradation efficiency of 58% and 86% was obtained for the degradation of MB and MG respectively and 85.9% of corrosion inhibition efficiency was also achieved. The results proved that functionalization of nanoparticles will lead enhancement of the following mediated synthesized EDTA functionalized α -Fe2O3 is a promising material to use for different application. Hence, green synthesized NPs are expected to offer significant insight into their multifunctional applications.

Multifunctional metal-organic framework with pH-response for co-delivery of prochloraz and siRNA to synergistic control pathogenic fungi

We first report a pH-responsive multifunctional nano pesticide-fertilizer complex based on zeolitic imidazolate framework-8 (ZIF-8) and RNA interference (RNAi) technology for synergistic control of wilt disease caused by Rhizoctonia solani, and promotion of crop growth. Chemical pesticide prochloraz (Pro), biological pesticide small interfering RNA (siRNA), and a plant growth regulator diethyl aminoethyl hexanoate (DA-6) were loaded in Pro/DA-6 @ZIF-8 @siRNA nanoparticles (Nps). The Nps had a rhombic orthododecahedron structure and a hydrated particle size of 841.7 ± 12.8 nm. SiRNA has good stability due to the protection of the nanocarrier as well as an excellent controlled-release behavior under acidic conditions due to the degradation of coordination bonds. The Nps can be adsorbed and transmitted via pathogenic mycelium to enhance the efficacy of non-invasive pesticides. Compared to Pro technical, siRNA and Pro co-delivered by ZIF-8 had a synergistic inhibitory effect on pathogenic fungi. Due to the slow-release of DA-6 and the supply of trace elements, the Nps significantly promoted rice seedling growth by regulation of key metabolic enzymes, and the nutritional function of Nps as a zinc ion fertilizer was demonstrated. Biological studies further verified that nano-carrier had good biosafety and reduced environmental risks. Therefore, this novel nano pesticide-fertilizer complex has potential applications for the effective management of plant disease to enhance environmental safety.

SOEing PCR/Docking Optimization of Protein A-G/scFv-Fc-Bioconjugated Au Nanoparticles for Interaction with Meningitidis Bacterial Antigen

Recent advances in the use of gold nanoparticles (Au NPs)/antibody conjugations in nanomedicine have increased the need to optimize the synthesis conditions and surface functionalization of Au NPs. In this study, a home-made Neisseria meningitidis recombinant antibody (scFv-Fc) was developed by connecting the fragment crystallizable (Fc) region of a human antibody with a mouse recombinant antibody (single-chain variable fragment antibody (scFv)) and characterized using the SOEing PCR technique. Then, an optimized gold coating agent for the scFv-Fc/Au NP conjugation (i.e., the citrate agent) was found among three common agents (citrate, allylamine hydrochloride, and polyvinyl alcohol) with different surface charges (negative, positive, and neutral, respectively). Moreover, the stability of the scFv-Fc/protein A-G in the presence of a N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) linker was investigated using the docking method. It was found that the designed scFv-Fc/protein A-G/SPDP/citrate recombinant antibody showed optimized bottom-on conjugation of the protein A-G with the improved scFv-Fc/Au NPs, enabling a suitable interaction with the Neisseria meningitidis bacterial antigen.

Imbedding Pd Nanoparticles into Porous In2O3 Structure for Enhanced Low-Concentration Methane Sensing.

Methane (CH4), as the main component of natural gas and coal mine gas, is widely used in daily life and industrial processes and its leakage always causes undesirable misadventures. Thus, the rapid detection of low concentration methane is quite necessary. However, due to its robust chemical stability resulting from the strong tetrahedral-symmetry structure, the methane molecules are usually chemically inert to the sensing layers in detectors, making the rapid and efficient alert a big challenge. In this work, palladium nanoparticles (Pd NPs) embedded indium oxide porous hollow tubes (In2O3 PHTs) were successfully synthesized using Pd@MIL-68 (In) MOFs as precursors. All In2O3-based samples derived from Pd@MIL-68 (In) MOFs inherited the morphology of the precursors and exhibited the feature of hexagonal hollow tubes with porous architecture. The gas-sensing performances to 5000 ppm CH4 were evaluated and it was found that Pd@In2O3-2 gave the best response (Ra/Rg = 23.2) at 370 °C, which was 15.5 times higher than that of pristine-In2O3 sensors. In addition, the sensing materials also showed superior selectivity against interfering gases and a rather short response/recovery time of 7 s/5 s. The enhancement in sensing performances of Pd@In2O3-2 could be attributed to the large surface area, rich porosity, abundant oxygen vacancies and the catalytic function of Pd NPs.

Hydroxyapatite Biobased Materials for Treatment and Diagnosis of Cancer.

Great advances in cancer treatment have been undertaken in the last years as a consequence of the development of new antitumoral drugs able to target cancer cells with decreasing side effects and a better understanding of the behavior of neoplastic cells during invasion and metastasis. Specifically, drug delivery systems (DDS) based on the use of hydroxyapatite nanoparticles (HAp NPs) are gaining attention and merit a comprehensive review focused on their potential applications. These are derived from the intrinsic properties of HAp (e.g., biocompatibility and biodegradability), together with the easy functionalization and easy control of porosity, crystallinity and morphology of HAp NPs. The capacity to tailor the properties of DLS based on HAp NPs has well-recognized advantages for the control of both drug loading and release. Furthermore, the functionalization of NPs allows a targeted uptake in tumoral cells while their rapid elimination by the reticuloendothelial system (RES) can be avoided. Advances in HAp NPs involve not only their use as drug nanocarriers but also their employment as nanosystems for magnetic hyperthermia therapy, gene delivery systems, adjuvants for cancer immunotherapy and nanoparticles for cell imaging.