Ecofriendly biosynthesis of copper nanoparticles from novel marine S. rhizophila species for enhanced antibiofilm, antimicrobial and antioxidant potential.

Marine microorganisms offer a promising avenue for the eco-friendly synthesis of nanoparticles due to their unique biochemical capabilities and adaptability to various environments. This study focuses on exploring the potential of a marine bacterial species, Stenotrophomonas rhizophila BGNAK1, for the synthesis of biocompatible copper nanoparticles and their application for hindering biofilms formed by monomicrobial species. The study begins with the isolation of the novel marine S. rhizophila species from marine soil samples collected from the West coast region of Kerala, India. The isolated strain is identified through 16S rRNA gene sequencing and confirmed to be S. rhizophila species. Biosynthesis of copper nanoparticles using S. rhizophila results in the formation of nanoparticles with size of range 10-50 nm. The nanoparticles exhibit a face-centered cubic crystal structure of copper, as confirmed by X-Ray Diffraction analysis. Furthermore, the synthesized nanoparticles display significant antimicrobial activity against various pathogenic bacteria and yeast. The highest inhibitory activity was against Staphylococcus aureus with a zone of 27 ± 1.00 mm and the least activity was against Pseudomonas aeruginosa with a zone of 22 ± 0.50 mm. The zone of inhibition against Candida albicans was 16 ± 0.60 mm. The antibiofilm activity against biofilm-forming clinical pathogens was evidenced by the antibiofilm assay and SEM images. Additionally, the copper nanoparticles exhibit antioxidant activity, as evidenced by their scavenging ability against DPPH, hydroxyl, nitric oxide, and superoxide radicals, as well as their reducing power in the FRAP assay. The study highlights the potential of the marine bacterium S. rhizophila BGNAK1 for the eco-friendly biosynthesis of copper nanoparticles with diverse applications. Synthesized nanoparticles exhibit promising antibiofilm, antimicrobial, and antioxidant properties, suggesting their potential utility in various fields such as medicine, wastewater treatment, and environmental remediation.

Cu2+-Mediated Aggregation of Gold Nanoparticles as an Optical Probe for the Detection of Endotoxin.

Endotoxins or lipopolysaccharides (LPS) present in the outer layer of Gram-negative bacteria (GNB) are responsible for bacterial toxicity. It is an environmental hazard that everyone is exposed to daily to various extents. Due to its potent toxicity, quantitative detection with very high sensitivity is essential in the food, medical, and pharmaceutical industries. Herein, we report an optical nanosensor for the rapid and sensitive detection of LPS and GNB based on the Cu2+-mediated aggregation of gold nanoparticles (Cu@AuNPs). The sensor detects LPS within a linear range of 20 ag/mL to 20 ng/mL with a lower detection limit of 0.2 ag/mL. The sensor could successfully recover spiked endotoxin in grape juice with a percentage error of ±0.2, confirming its application in the food industry. The sensor could also distinguish Gram-negative bacteria from Gram-positive bacteria, and the selectivity of the Cu@AuNP sensor toward GNB is utilized to detect Escherichia coli in wastewater. The rapid detection of E. coli without any pretreatment is a promising strategy in water analysis.

Fluorescent carbon dot embedded polystyrene: an alternative for micro/nanoplastic translocation study in leguminous plants.

Micro/nanoplastics are widespread in terrestrial ecosystem. Even though many studies have been reported on the effects of these in marine environment, studies concerning their accumulation and impact on terrestrial ecosystem have been scanty. The current study was designed to determine how terrestrial plants, especially legumes, interact with micro/nanoplastics to gain insights into their uptake and translocation. The paper describes the synthesis of fluorescent carbon dot embedded polystyrene (CDPS) followed by its characterization. Translocation studies at different concentrations from 2 to 100% (v/v) for tracking the movement and accumulation of microplastics in Vigna radiata and Vigna angularis were performed. The optical properties of the synthesized CDPS were investigated, and their translocation within the plants was visualized using fluorescence microscopy. These findings were further validated by scanning electron microscopy (SEM) imaging of the plant sections. The results showed that concentrations higher than 6% (v/v) displayed noticeable fluorescence in the vascular region and on the cell walls, while concentrations below this threshold did not. The study highlights the potential of utilizing fluorescent CDPS as markers for investigating the ecological consequences and biological absorption of microplastics in agricultural systems. This method offers a unique technique for monitoring and analyzing the routes of microplastic accumulation in edible plants, with significant implications for both food safety and environmental health.

3D printed arrowroot starch-gellan scaffolds for wound healing applications.

Skin, the largest organ in the body, blocks the entry of environmental pollutants into the system. Any injury to this organ allows infections and other harmful substances into the body. 3D bioprinting, a state-of-the-art technique, is suitable for fabricating cell culture scaffolds to heal chronic wounds rapidly. This study uses starch extracted from Maranta arundinacea (Arrowroot plant) (AS) and gellan gum (GG) to develop a bioink for 3D printing a scaffold capable of hosting animal cells. Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction analysis (XRD) prove that the isolated AS is analogous to commercial starch. The cell culture scaffolds developed are superior to the existing monolayer culture. Infrared microscopy shows the AS-GG interaction and elucidates the mechanism of hydrogel formation. The physicochemical properties of the 3D-printed scaffold are analyzed to check the cell adhesion and growth; SEM images have confirmed that the AS-GG printed scaffold can support cell growth and proliferation, and the MTT assay shows good cell viability. Cell behavioral and migration studies reveal that cells are healthy. Since the scaffold is biocompatible, it can be 3D printed to any shape and structure and will biodegrade in the requisite time.

Intracellular trafficking of superparamagnetic iron oxide nanoparticles conjugated with TAT peptide: 3-dimensional electron tomography analysis.

Internalisation of nanoparticles conjugated with cell penetrating peptides is a promising approach to various drug delivery applications. Cell penetrating peptides such as transactivating transcriptional activator (TAT) peptides derived from HIV-1 proteins are effective intracellular delivery vectors for a wide range of nanoparticles and pharmaceutical agents thanks to their amicable ability to enter cells and minimum cytotoxicity. Although different mechanisms of intracellular uptake and localisation have been proposed for TAT conjugated nanoparticles, it is necessary to visualise the particles on a 3-D plane in order to investigate the actual intracellular uptake and localisation. Here, we study the intracellular localisation and trafficking of TAT peptide conjugated superparamagnetic ion oxide nanoparticles (TAT-SPIONs) using 3-D electron tomography. 3-D tomograms clearly show the location of TAT-SPIONs in a cell and their slow release from the endocytic vesicles into the cytoplasm. The present methodology may well be utilised for further investigations of the behaviours of nanoparticles in cells and eventually for the development of nano drug delivery systems.

An assessment of skeletal craniofacial asymmetry in South Indian population.

The present study was undertaken to assess the skeletal craniofacial asymmetry in South Indian population by a posteroanterior cephalometric radiographic method. The skeletal craniofacial structures on one side of the face were compared with that of the other, by drawing various triangles representing different craniofacial regions. The sample consisted of 60 subjects (30 males and 30 females) aged between 18 to 25 years, who were mainly dental college students from South India. Overall 52 X-rays were obtained, with four errors each in the male and the female groups. The results revealed that the total facial structures in the South Indian population were larger on the left side (statistically insignificant). The cranial base area exhibited a greater degree of asymmetry than any other component area of the face, which might be due to the inaccuracy at the condylar point.

Promising bioactive compounds from the marine environment and their potential effects on various diseases.

BACKGROUND: The marine environment hosts a wide variety of species that have evolved to live in harsh and challenging conditions. Marine organisms are the focus of interest due to their capacity to produce biotechnologically useful compounds. They are promising biocatalysts for new and sustainable industrial processes because of their resistance to temperature, pH, salt, and contaminants, representing an opportunity for several biotechnological applications. Encouraged by the extensive and richness of the marine environment, marine organisms' role in developing new therapeutic benefits is heading as an arable field. There is currently much interest in biologically active compounds derived from natural resources, especially compounds that can efficiently act on molecular targets, which are involved in various diseases. Studies are focused on bacteria and fungi, isolated from sediments, seawater, fish, algae, and most marine invertebrates such as sponges, mollusks, tunicates, coelenterates, and crustaceans. In addition to marine macro-organisms, such as sponges, algae, or corals, marine bacteria and fungi have been shown to produce novel secondary metabolites (SMs) with specific and intricate chemical structures that may hold the key to the production of novel drugs or leads. The marine environment is known as a rich source of chemical structures with numerous beneficial health effects. Presently, several lines of studies have provided insight into biological activities and neuroprotective effects of marine algae, including antioxidant, anti-neuroinflammatory, cholinesterase inhibitory activity, and neuronal death inhibition. CONCLUSION: The application of marine-derived bioactive compounds has gained importance because of their therapeutic uses in several diseases. Marine natural products (MNPs) display various pharmaceutically significant bioactivities, including antibiotic, antiviral, neurodegenerative, anticancer, or anti-inflammatory properties. The present review focuses on the importance of critical marine bioactive compounds and their role in different diseases and highlights their possible contribution to humanity.

Implantable Microfluidic Device: An Epoch of Technology.

Implantable microfluidic devices are milestones in developing devices that can measure parameters like ocular pressure and blood glucose level or deliver various components for therapeutic needs or behavioral modification. Researchers are currently focusing on the miniaturization of almost all its tools for a better healthcare platform. Implantable microfluidic devices are a combination of various systems including, but not limited to, microfluidic platforms, reservoirs, sensors, and actuators, implanted inside the body of a living entity (in vivo) with the purpose of directly or indirectly helping the entity. It is a multidisciplinary approach with immense potential in the area of the biomedical field. Significant resources are utilized for the research and development of these devices for various applications. The induction of an implantable microfluidic device into an animal would enable us to measure the responses without any repeated invasive procedures. Such data would help in the development of a better drug delivery profile. Implantable microfluidic devices with reservoirs deliver specific chemical or biological products to treat situations like cancers and diabetes. They can also deliver fluorophores for specific imaging inside the body. Implantable microfluidic devices help provide a microenvironment for various cell differentiation procedures. These devices know no boundaries, and this article reviews these devices based on their design and applications.

A comparative study of impression procedures for distal extension removable partial dentures.

AIM: This study was carried out with the purpose of comparing three impression methods as to which of them placed tissues most favorably. METHODS: The methods used were Hindels method, selective tissue placement method and functional reline method. The measurements obtained were analyzed to determine which of the three impression methods placed the mucosal tissues maximally. To compare and measure tissue placements, autopolymerizing acrylic resin platforms were constructed to the height of the occlusal surfaces of the remaining teeth. 15 orthodontic buccal tubes were placed on each side of the platform. They were arranged in three sets of five and attached to the platform over selected reference regions by means of autopolymerizing resin. The selected reference areas were in anterior, middle and posterior areas of the ridge on either side. RESULTS: No significant difference was seen in tissue placement in the anterior middle and posterior regions in each of the three methods when each method was assessed separately. Selective tissue placement method placed the tissues maximally (7.547 mm) followed by Hindels method (7.2110 mm) and the least placement was by functional reline method (5.856 mm). Tissue placement was significantly higher in Hindels method as compared to functional reline method (p < 0.001). CONCLUSION: Tissue placement was maximum in the posterior region, followed by the middle region and least in the anterior region of the mandibular ridge for all three methods. Selective tissue placement method showed the maximum overall tissue placement followed by the Hindels method and minimum placement was by functional reline method. CLINICAL SIGNIFICANCE: Selective tissue placement method provided maximum overall tissue placement and can be a preferred technique for impression making for bilateral distal extension removable partial denture fabrication.

Aptamer conjugated magnetic nanoparticles as nanosurgeons.

Magnetic nanoparticles have shown promise in the fields of targeted drug delivery, hyperthermia and magnetic resonance imaging (MRI) in cancer therapy. The ability of magnetic nanoparticles to undergo surface modification and the effect of external magnetic field in the dynamics of their movement make them an excellent nanoplatform for cancer destruction. Surgical removal of cancerous or unwanted cells selectively from the interior of an organ or tissue without any collateral damage is a serious problem due to the highly infiltrative nature of cancer. To address this problem in surgery, we have developed a nanosurgeon for the selective removal of target cells using aptamer conjugated magnetic nanoparticles controlled by an externally applied three-dimensional rotational magnetic field. With the help of the nanosurgeon, we were able to perform surgical actions on target cells in in vitro studies. LDH and intracellular calcium release assay confirmed the death of cancer cells due to the action of the nanosurgeon which in turn nullifies the possibility of proliferation by the removed cells. The nanosurgeon will be a useful tool in the medical field for selective surgery and cell manipulation studies. Additionally, this system could be upgraded for the selective removal of complex cancers from diverse tissues by incorporating various target specific ligands on magnetic nanoparticles.

End-Sealed High Aspect Ratio Hollow Nanotubes Encapsulating an Anticancer Drug: Torpedo-Shaped Peptidic Nanocapsules.

Nanomaterial morphology is important for the targeted delivery of drugs to tissues as well as subsequent cellular uptake. Hollow nanotubes composed of peptides, with a diameter of 80 nm and various lengths (100, 200, 300, 600 nm), were successfully capped and sealed with a peptide hemisphere to encapsulate the anticancer drug, cisplatin. The torpedo-shaped nanocapsules with an aspect ratio (length/diameter) of 2.4 showed more rapid cellular uptake and accumulation at the tumor site compared with spherical analogues. Successful delivery of cisplatin to tumors was achieved in a mouse model and tumor growth was efficiently suppressed.

Template-Assisted Formation of Nanostructured Dopamine-Modified Polymers.

Dopamine-modified alginate and gelatin were prepared. The polymers were characterized and the properties of their aqueous solutions were investigated. Aqueous solutions of dopamine-modified alginate and gelatin with a concentration exceeding 20 mg/mL naturally formed gels after 16 h. Although polydopamine itself was not used for template-assisted nanostructure formation, the modified polymers could be used with dopamine. Mixing with dopamine allowed the precise shape of the template to be maintained in the resulting material, allowing nanopatterned surfaces and nanotubes to be prepared.

Enhancement of synergistic gene silencing by RNA interference using branched "3-in-1" trimer siRNA.

Nanostructured RNA carrying three different siRNAs was assembled to silence three target genes (Axin, APC, and GSK-3ß) in the Wnt/ß-catenin signaling pathway. The trimer RNA nanostructure included equimolar concentrations of three oligonucleotide sequences. The three armed structures and the size of the trimer RNA were confirmed by agarose gel electrophoresis, atomic force microscopy, and dynamic light scattering. In the presence of 10% human serum, the trimer RNA was able to resist degradation and maintained an intact structure for more than two hours. Protein expression analyses showed specific repression of the target proteins by siRNAs. As a result, the expression of luciferase in a ß-catenin reporter vector was significantly increased by the trimer RNA compared with a pool of the three individual siRNAs. This high activity at a low concentration was considered to be due to the 3-in-1 format of the trimer and the long-term resistance to serum proteins by nanostructure formation. We demonstrated that a nanostructured "3-in-1" siRNA is effective in enhancing the effect of RNA interference.

High Density of Aligned Nanowire Treated with Polydopamine for Efficient Gene Silencing by siRNA According to Cell Membrane Perturbation.

High aspect ratio nanomaterials, such as vertically aligned silicon nanowire (SiNW) substrates, are three-dimensional topological features for cell manipulations. A high density of SiNWs significantly affects not only cell adhesion and proliferation but also the delivery of biomolecules to cells. Here, we used polydopamine (PD) that simply formed a thin coating on various material surfaces by the action of dopamine as a bioinspired approach. The PD coating not only enhanced cell adhesion, spreading, and growth but also anchored more siRNA by adsorption and provided more surface concentration for substrate-mediated delivery. By comparing plain and SiNW surfaces with the same amount of loaded siRNA, we quantitatively found that PD coating efficiently anchored siRNA on the surface, which knocked down the expression of a specific gene by RNA interference. It was also found that the interaction of SiNWs with the cell membrane perturbed the lateral diffusion of lipids in the membrane by fluorescence recovery after photobleaching. The perturbation was considered to induce the effective delivery of siRNA into cells and allow the cells to carry out their biological functions. These results suggest promising applications of PD-coated, high-density SiNWs as simple, fast, and versatile platforms for transmembrane delivery of biomolecules.

Transmembrane molecular transport through nanopores formed by protein nanotubes.

Protein nanotubes formed by layer-by-layer (LbL) assembly can penetrate cells and act as nanopores for direct transmembrane delivery of chemical compounds.

Nanotechnology platforms; an innovative approach to brain tumor therapy.

Nano Drug Delivery, as a treatment method against brain tumors, is a progressing area in the field of precise targeted drug administration methodology. The unresolved problems related to chemotherapy, other invasive therapeutic procedures and various obstructions offered by biological barriers are circumvented by nanodrug delivery. Recent dramatic developments in nanotechnology have created a lot of nano-devices which could be used against cancer. Infiltration, modulation of the Blood Brain Barrier, camouflaged from immune defense mechanism and the specific targeting of cancer affected cells are a few of the attractive features of nanodevices. We present here a review of newly evolved nanoplatforms in brain tumor therapy in which careful attention has been paid into various form nanoparticles, useful targeting ligands, altered chemotherapy agents and existing tumor therapy methods using nanotechnology.

Label-free determination of the number of biomolecules attached to cells by measurement of the cell's electrophoretic mobility in a microchannel.

We developed a label-free method for a determination of the number of biomolecules attached to individual cells by measuring the electrophoretic mobility of the cells in a microchannel. The surface of a biological cell, which is dispersed in aqueous solution, is normally electrically charged and the charge quantity at the cell's surface is slightly changed once antibody molecules are attached to the cell, based on which we detect the attachment of antibody molecules to the surface of individual red blood cells by electrophoretic mobility measurement. We also analyzed the number of antibody molecules attached to the cell's surface using a flow cytometer. We found that there is a clear correlation between the number of antibody molecules attached to the individual cells and the electrophoretic mobility of the cells. The present technique may well be utilized not only in the field of cell biology but also in the medical and pharmaceutical industries.

Blood compatibility of surface modified poly(ethylene terephthalate) (PET) by plasma polymerized acetobromo-alpha-D-glucose.

Poly (ethylene terephthalate) (PET) was surface modified by plasma polymerization of acetobromo-alpha-D-glucose (ABG) at different radio frequency (RF) powers. Plasma polymerization was carried out by vaporizing ABG in the powder form by heating at 135 degrees C. Surface modification resulted in improved hydrophilicity and smoothness of the surface especially at low RF powers (30-50 W), but at high RF powers, the surface was found to be etched and the hydrophilicity decreased as evidenced by atomic force microscopy (AFM) and contact angle measurements. The plasma polymerized ABG film was found to be extensively cross-linked as evidenced by its insolubility in water. Infra red (IR) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the plasma polymerized ABG films. IR studies revealed that at lower RF powers, polymerization was taking place mainly by breaking up of acetoxy group while retaining the ring structures to a major extent during the polymerization process whereas at high RF powers, the rupture of ring structures was indicated. XPS indicated a reduction in the percentage of oxygen in the polymers going from low to high RF powers suggestive of complete destruction of the acetoxy group at high RF powers. Cross-cut tests showed excellent adhesive properties of the plasma polymerized ABG films onto PET. Static platelet adhesion tests using platelet rich human plasma showed significantly reduced adhesion of platelets onto modified PET surface as evidenced by scanning electron microscopy. Polymerization of glucose and its derivatives using RF plasma has not been reported so far and the preliminary results reported in this study shows that this could be an interesting approach in the surface modification of biomaterials.