A deep delve into the chemistry and biocompatibility of halloysite nanotubes: A new perspective on an idiosyncratic nanocarrier for delivering drugs and biologics.

HNTs have garnered a substantial amount of scientific interest over the years owing to its green nature, unique surface chemistry and the ability to load any guest molecule. These nanostructures are biocompatible and are thus perfect nanocarriers for the delivery of drugs and therapeutic biologics. However, in order to fully achieve its potential as a nanocarrier, several nuances to its surface chemistry and release kinetics must be kept in mind. Factors like the choice of compound for functionalization of HNTs and the microenvironmental pH of the targeted area are obvious yet intricate and crucial to ensure optimum therapeutic effect with minimized side effect profile. This article comprehensively reviews the safety profile of pristine and modified HNTs across different cell lines and model organisms. Furthermore, we also aim to provide an insight into the unique chemistry involved between drugs or biomolecules and the functional moieties on the surface of HNTs, which evidently alters the release rate of these guest molecules. Lastly, this focused review on drug delivery aims at providing critical comments and highlighting unexplored avenues in the current progress of research.

Environmental damages due to war in Ukraine: A perspective.

The ongoing Russia-Ukraine war is the most prominent conflict in Europe since the Second World War and has several geopolitical, economic, infrastructure, and health implications. The war has serious negative consequences on people and the planet. The damage to industrial and commercial infrastructure can contaminate water sources, which can be hazardous for human and ecosystem health. Water shortages and deteriorating sanitary conditions are already evident since water supply and sanitary infrastructure have been hit. Air quality is adversely affected due to troop movement and constant bombarding. Chances of radiation leakage from nuclear sites also remain. The physical, chemical and biological characteristics of soil have been impacted due to shelling and explosions, as a result of which, agriculture has been severely affected. Military actions have caused large-scale deforestation and even wildfires. There is also fear of biodiversity loss and species extinction in the long term. The war of such nature may directly hamper efforts to deal with aspects such as climate change, sustainable development goals (SDGs), conservation and protection of biodiversity, and pollution control at local and global levels. Besides this, the repercussions of this war on essential services such as healthcare, education, social security, and public amenities will be felt for a long. As a result of important interruptions in the supply of energy and raw materials throughout the world, prices for commodities, oil, and food have risen dramatically. To avert such damages in the future and make the offenders accountable, in the long term, reforms in the mandate of the International Criminal Court are required to include environmental crimes. New international norms to safeguard the environment during conflict are urgently needed. The environment should not be considered an unavoidable war casualty. Environmental and human security are inextricably linked. The international community's reaction to the crisis must include addressing this as a priority.

Risk assessment of selected pharmaceuticals on wildlife with nanomaterials based aptasensors.

Pharmaceuticals have improved human and veterinary health tremendously over the years. But the implications of the presence of pharmaceuticals in the environment on terrestrial, avian, and aquatic organisms are still not fully comprehended. The bioaccumulation and biomagnifications of these chemicals through the food chain have long-term effects on the wildlife. The detection and quantification of such pharmaceutical residues in the environment is a tedious process and quicker methods are needed. Aptasensors are one such quick and reliable method for the identification of pharmaceutical residues in the wildlife. Aptasensors are a class of biosensors that work on the principles of biological recognition of elements. The aptamers are unique biological recognition elements with high specificity and affinity to various targets. Their efficiency makes them a very promising candidate for such sensitive research. In this review, the pharmaceutical threats to wildlife and their detection techniques using aptasensors have been discussed.

Food forensics: Techniques for authenticity determination of food products.

The need for reliable and precise analytical techniques for food authentication and traceability has increased in recent decades due to the excessive competition for the production of competitive food products which leads to a high chance of food fraud. In this article, applications of several analytical techniques such as DNA-based techniques, spectrometric techniques, spectroscopic techniques, chromatographic techniques, lateral flow immunoassays, and neutron and proton based nuclear analytical techniques for forensic food analysis have been discussed. These sophisticated techniques are capable to analyze the food samples rapidly and permit the identification of specific parameters which are useful for investigations of food frauds in various legal issues. These techniques also pave-the-way, to discover the answers to many important analytical questions relating to food authentication and traceability in the field of food forensics. In addition, forensic analysis of dyes in food, seafood, plant-based food, beverages, and forensic analysis of postmortem viscera are reviewed.

Chitosan functionalized Halloysite Nanotubes as a receptive surface for laccase and copper to perform degradation of chlorpyrifos in aqueous environment.

Chitosan (CTS) functionalized Halloysite Nanotubes (HNT) have been used as receptive nano-supports for the grafting of copper (Cu) and laccase (Lac) for the degradation of chlorpyrifos. The developed nanocomposite Lac@Cu-CTS-HNT showed 83.4% Lac immobilization which was further characterized by TEM, SEM-EDX, FTIR, XRD, DSC and TGA. The chlorpyrifos degradation studies were performed under constant stirring for 24 h with both free enzyme and Lac@Cu-CTS-HNT and were analysed through HPLC. Percentage degradation of chlorpyrifos with the nanocomposite went as high as 97% for 50 µg/mL chlorpyrifos at neutral pH and room temperature. Variable pesticide and nanocomposite concentration, pH, and temperature studies for pesticide degradation were also performed, followed by reusability studies. The nanocomposite maintained its degradation ability at ~97% even at variable temperature and pH conditions. Reusability study was performed 5 times wherein the degradation percentage remained the same after 5 cycles (~<95%). Degradation kinetics were also performed for the nanocomposite in the presence and absence of the immobilized enzyme. Through this study, it is suggested that Lac@Cu-CTS-HNT can be a potential nano-catalyst for the degradation of chlorpyrifos in aqueous environment.

Development, characterization and in vitro-in vivo evaluation of Farnesol loaded niosomal gel for applications in oral candidiasis treatment.

OBJECTIVES: The aim of the study was to formulate and characterize the farnesol loaded niosomes comprising gel formulation and perform their in vitro-in vivo evaluation for applications in the treatment of oral candidiasis infections. METHODS: Various gelling systems were evaluated for their rheological and stability properties. The formulation was statistically optimized using experimental design method (Box-Behnken). Transmission electron microscopy (TEM) and Atomic force microscopy (AFM) were used to observe the niosomal surface morphology. Centrifugation method and dialysis method were used to find out the % entrapment efficiency (%EE) and in-vitro release of Farnesol, respectively. In-vitro antifungal effect and cell biocompatibility of the Farnesol loaded niosomal gel was also performed using Candida albicans (C. albicans) as the model organism and epithelial cell line (SW480) by MTT cytotoxicity assay. In-vivo skin irritation test was performed on rabbit skin. KEY FINDINGS: Farnesol loaded niosomes were integrated into polymeric gel solution. The optimized formulation demonstrated acceptable % EE (>80%) and an optimum particle size (168.8 nm) along with a sustained release and a long-term storage stability for up to a period of 6 months. TEM and AFM observations displayed a spherical niosome morphology. Farnesol niosomal gel showed a higher antifungal efficacy, ex-vivo skin permeation and deposition in comparison to plain farnesol solution. The niosomal gel also showed negligible cytotoxicity to normal cells citing biocompatibility and was found to be non-toxic and non-irritant to rabbit skin. CONCLUSIONS: This novel niosome loaded gel-based formulation could make the oral candidiasis healing process more efficient while improving patient compliance. With the optimized methodology used in this work, such formulation approaches can become an efficient, industrially scalable, and cost-effective alternatives to the existing conventional formulations.

Understanding intricacies of bioinspired organic-inorganic hybrid nanoflowers: A quest to achieve enhanced biomolecules immobilization for biocatalytic, biosensing and bioremediation applications.

The immobilization of biomolecules has been a subject of interest for scientists for a long time. The organic-inorganic hybrid nanoflowers are a new class of nanostructures that act as a host platform for the immobilization of such biomolecules. It provides better practical applicability to these functional biomolecules while also providing superior activity and reusability when catalysis is involved. These nanostructures have a versatile and straightforward synthesis process and also exhibit enzyme mimicking activity in many cases. However, this facile synthesis involves many intricacies that require in-depth analysis to fully attain its potential as an immobilization technique. A complete account of all the factors involving the synthesis process optimisation is essential to be studied to make it commercially viable. This paper explores all the different aspects of hybrid nanoflowers which sets them apart from the conventional immobilization techniques while also giving an overview of its wide range of applications in industries.

Design, development and in-vitro/in-vivo evaluation of intranasally delivered Rivastigmine and N-Acetyl Cysteine loaded bifunctional niosomes for applications in combinative treatment of Alzheimer's disease.

The present investigation explores the potential of novel dual drug-loaded niosomes for nasal delivery of Rivastigmine (RIV) and N-Acetyl Cysteine (NAC) to the brain. The dual niosomes showed a particle size of 162.4 nm and % entrapment efficiencies of 97.7% for RIV and 85.9% for NAC. The niosomes were statistically validated using Box-Behnken experimental design (BBD) with good significance. Ultrastructural and chemical characterization of the niosomes using various analytical techniques like Fourier Transform Infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), Transmission electron microscopy (TEM) showcased drug-excipient compatibility and robust stability of 6 months in a liquid state at 4-8 °C. The dual drug-loaded niosomes showed a sustained drug release pattern up to 2 days. Acetylcholinesterase (AChE) and DPPH (1, 1-diphenyl-2- picrylhydrazyl) enzyme inhibition assays showed a better combinative effect than the free drug solutions. A 2-day nasal permeation proved the effectiveness and biocompatibility of the niosomes. In-vivo pharmacokinetic and organ biodistribution studies revealed a better drug profile and greater distribution of the niosomes in the brain compared to other organs, thereby indicating a direct nose-to-brain delivery of the niosomes.

Environmental perspective of COVID-19.

The outbreak of COVID-19 has caused concerns globally. On 30 January WHO has declared it as a global health emergency. The easy spread of this virus made people to wear a mask as precautionary route, use gloves and hand sanitizer on a daily basis that resulted in generation of a massive amount of medical wastes in the environment. Millions of people have been put on lockdown in order to reduce the transmission of the virus. This epidemic has also changed the people's life style; caused extensive job losses and threatened the sustenance of millions of people, as businesses have shut down to control the spread of virus. All over the world, flights have been canceled and transport systems have been closed. Overall, the economic activities have been stopped and stock markets dropped along with the falling carbon emission. However, the lock down of the COVID-19 pandemic caused the air quality in many cities across the globe to improve and drop in water pollutions in some parts of the world.

Physicochemical and biological assessment of silver nanoparticles immobilized Halloysite nanotubes-based resin composite for dental applications.

OBJECTIVE: The purpose of this study was to investigate the effect of Silver nanoparticle immobilized Halloysite Nanotubes (HNT/Ag) fillers on physicochemical, mechanical, and biological properties of novel experimental dental resin composite in order to compare with the properties of corresponding composites containing conventional glass fillers. METHODS: Dental resin (Bis-GMA/TEGDMA with ratio 70/30) composites were prepared by incorporation of varied mass fraction of HNT/Ag. Experimental composites were divided into six groups, one control group and five experimental groups containing mass fraction 1 to 10.0 wt. % of HNT/Ag. Mechanical properties of the dental composites were recorded. Degree of conversion and depth of cure of the dental resin composites were assessed. Antimicrobial properties were assessed using agar diffusion test and evaluation of cytotoxicity were performed on NIH-3T3 cell line. RESULTS: The inclusion of mass fractions (1-5 wt. %) of the HNT/Ag in dental resins composites, significantly improved mechanical properties. While, addition of larger mass fractions (7.5 and 10 wt. %) of the HNT/Ag did not show further improvement in the mechanical properties of dental resins composites. Theses composites also demonstrated satisfactory depth of cure and degree of conversion. A significant antibacterial activity was observed on S. mutans. No significant cytotoxicity was found on NIH-3T3 cell lines. CONCLUSION: The incorporation of HNT/Ag in Bis-GMA/TEGDMA dental resins composites resulted in enhancement in mechanical as well as biological properties for dental applications. CLINICAL SIGNIFICANCE: HNT/Ag containing dental composite is proposed to be highly valuable in the development of restorative dental material for patients with high risk of dental caries.

Physicochemical and biological assessment of flowable resin composites incorporated with farnesol loaded halloysite nanotubes for dental applications.

The aim of this study was to fabricate flowable resin composites, by incorporating Farnesol loaded Halloysite Nanotubes (Fa-HNT) as a filler and evaluate their physicochemical as well as biological properties. Chemical and morphological characterization of antibacterial filler, Fa-HNT were performed using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM). The antibacterial filler was mixed into composite material consisting of methacrylate monomers and dental glass fillers at concentrations of 1-20% (wt./wt.). It was observed that addition of mass fractions of Fa-HNT causes enhancement of compressive strength as well as flexural modulus of the composite. However, it significantly decreases flexural strength and degree of conversion. A significant antibacterial activity of dental composite was observed with increase in the area of zone of inhibition against the strains of Streptococcus mutans (S. mutans). There was no cytotoxicity observed by Fa-HNT resin composites on NIH-3T3 (mouse embryonic fibroblast cells) cell lines. A favourable integration of antibacterial filler with significant mechanical properties was achieved at concentrations from 7 to 13 wt% of Fa-HNT in dental composites, which is desirable in dentistry.

Nano-interfacial decoration of Halloysite Nanotubes for the development of antimicrobial nanocomposites.

In recent times, incorporation of Halloysite Nanotubes (HNTs) with various antimicrobial agents as interfacial materials between these nanotubes and pathogenic microorganisms, for the development of antimicrobial nanocomposites with enhanced antimicrobial activities has gained researcher's interest. The main benefits given by HNT to these nanocomposites include enhanced thermal and mechanical stability of the antimicrobial nanocomposites and also prolong durability and release of the antimicrobial agents in a sustained manner. The exceptional structure of these aluminosilicate minerals based nanotubes (hollow tubular lumen with huge surface area) and oppositely charged surface molecules assist in attaching various molecules on both, the internal surface as well as on the outer surface of these nanotubes. Other advantages of these clay-based minerals are their biocompatibility, non-toxicity, eco-friendly nature and their natural availability with affordable price, which also contribute in selecting them as supporting material for biological applications. Therefore, these clay-based nanotubes have been recently used for developing various antimicrobial nanocomposites. In this review, various antimicrobial nanocomposites developed through incorporation of HNT with myriad antimicrobial agents such as nanoparticles, metal ions, antibiotics, essential oils, biopolymers, phenolic compounds, surfactants and food preservatives as an interface between these nanotubes and microorganisms have been discussed. These antimicrobial nanocomposites could be synthesized in different forms (powder, film, nanocapsule and adhesive) which can be applicable in various fields such as food packaging, water decontamination, waste water management, healing of wounds, antimicrobial agents for surfaces, orthopedics and for the treatment of microbial infections.

Hyaluronic acid: A review on its biology, aspects of drug delivery, route of administrations and a special emphasis on its approved marketed products and recent clinical studies.

Hyaluronic acid (HA) is a large non-sulphated glycosaminoglycan that is an important component of extracellular matrix (ECM) and a biodegradable polymer. Due to a variation in its molecular weight, HA derivatives can be utilized to make different formulations like fillers, creams, gels and drops. HA based drug research has seen a recent surge largely due to some properties like mucoadhesion, biocompatibility and ease of chemical modification. Such properties of HA have led to applications in tissue regeneration, anti-aging and anti-inflammatory medications. HA can be conjugated, functionalized or used as a nanocarrier supplement with a definite increase in its cellular uptake and efficiency. HA when encapsulated in a nanocarrier may help to improve the ECM growth and provide a sustained release of agents. This review discusses the mechanistic behavior of HA pertaining to its biological synthesis and degradation. It also discusses the administration of some noteworthy and recent HA based formulations through different routes for application in various physiological conditions along with their ongoing clinical trial updates and approved marketed products.

Halloysite nanotubes as a nature's boon for biomedical applications.

The arena of biomedical science has long been in quest of innovative mediums for diagnostic and therapeutic applications. The latest being the use of nanomaterials for such applications, thereby giving rise to the branch of nanomedicine. Halloysite nanotubes (HNTs) are naturally occurring tubular clay nanomaterials, made of aluminosilicate kaolin sheets rolled several times. The aluminol and siloxane groups on the surface of HNT facilitate the formation of hydrogen bonding with the biomaterials onto its surface. These properties render HNT pivotal in diverse range of applications, such as in environmental sciences, waste-water treatment, dye removal, nanoelectronics and fabrication of nanocomposites, catalytic studies, as glass coatings or anticorrosive coatings, in cosmetics, as flame retardants, stimuli response, and forensic sciences. The specific properties of HNT also lead to numerous applications in biomedicine and nanomedicine, namely drug delivery, gene delivery, tissue engineering, cancer and stem cells isolation, and bioimaging. In this review, recent developments in the use of HNT for various nanomedicinal applications have been discussed.

Application of Box-Behnken Design in the Preparation, Optimization, and In Vitro Evaluation of Self-Assembly-Based Tamoxifen- and Doxorubicin-Loaded and Dual Drug-Loaded Niosomes for Combinatorial Breast Cancer Treatment.

This study was developed with the objective to prepare self-assembled niosomes to support sufficient entrapment and sustained drug release of the drugs having different solubility and mechanisms. In the current work, Tamoxifen- and Doxorubicin-loaded niosomes were prepared for combinatorial breast cancer treatment with statistical optimization by Box-Behnken experimental design. Atomic force microscopy revealed a spherical shape morphology of the niosomes. The entrapment efficiencies for the drugs were found to be 74.3% and 72.7% for Tamoxifen and Doxorubicin, respectively. The drug release experiments at different pH values displayed a sustained release up to 3 days. Fourier transform infrared spectroscopy and differential scanning calorimetry showed a robust drug-excipient compatibility. The niosomes were stable over a period of 6 months with no significant changes. In vitro cytotoxicity studies on MCF-7 cell line showed a 15-fold improvement (0.01 µg per mL) and a better synergistic effect of the niosomes in comparison to the free drug combination (0.15 µg per mL). Moreover, the nanocarrier uptake studies by fluorescence microscopy and flow cytometry showed a good distribution and greater uptake of the niosomes throughout the cells. These results suggest a profound therapeutic application of the niosomes for a combinatorial breast cancer treatment.

Surface modified halloysite nanotubes: A flexible interface for biological, environmental and catalytic applications.

Halloysite Nanotubes (HNTs) are clay minerals that possess unique chemical composition and a tubular structure due to which, they have recently emerged as a potential nanomaterial for umpteen applications. Over the years, the myriad applications of HNT have been realized through the surface modification of HNT, which involves the modification of nanotube's inner lumen and the outer surface with different functional compounds. The presence of aluminum and silica groups on the inner and outer surface of HNT enhance the interfacial relationship of the nanotube with different functional agents. Compounds such as alkalis, organosilanes, polymers, compounds of biological origin, surfactants and nanomaterials have been used for the modification of the inner lumen and the outer surface of HNT. The strategies change the constitution of HNT's surface either through micro-disintegration of the surface or by introducing additional functional groups on the surface, which further enhances their potential to be used as a flexible interface for different applications. In this review, the different surface modification strategies of the outer surface and the inner lumen that have been employed over the years have been discussed. The biological, environmental and catalytic applications of these surface modified HNTs with such versatile interface in the past two years have been elaborately discussed as well.

Nanotechnology-based recent approaches for sensing and remediation of pesticides.

Pesticides are meant to control and destroy the pests and weeds. They are classified into different categories on the basis their origin and type of pest they target. Chemical pesticides such as insecticides, herbicides and fungicides are commonly used in agricultural fields. However, the excessive use of these agrochemicals have adverse effects on environment such as reduced population of insect pollinators, threat to endangered species and habitat of birds. Upon consumption; chemical pesticides also cause various health issues such as skin, eye and nervous system related problems and cancer upon prolonged exposure. Various techniques in the past have been developed on the basis of surface adsorption, membrane filtration and biological degradation to reduce the content of pesticides. However, slow response, less specificity and sensitivity are some of the drawbacks of such techniques. In recent times, Nanotechnology has emerged as a helping tool for the sensing and remediation of pesticides. This review focuses on the use of this technology for the detection, degradation and removal of pesticides. Nanomaterials have been classified into nanoparticles, nanotubes and nanocomposites that are commonly used for detection, degradation and removal of pesticides. The review also focuses on the chemistry behind the sensing and remediation of pesticides using nanomaterials. Different types of nanoparticles, viz. metal nanoparticles, bimetallic nanoparticles and metal oxide nanoparticles; nanotubes such as carbon nanotubes and halloysite nanotubes have been used for the detection, degradation and removal of pesticides. Further, various enzyme-based biosensors for detection of pesticides have also been summarized.

Rural environment study for water from different sources in cluster of villages in Mehsana district of Gujarat.

Water pollution and water scarcity are major environmental issues in rural and urban areas. They lead to decline in the quality of water, especially drinking water. Proper qualitative assessment of water is thus necessary to ensure that the water consumed is potable. This study aims to analyze the physicochemical parameters in different sources of water in rural areas and assess the quality of water through a classification system based on BIS and CPCB standards. The classification method has defined water quality in six categories, viz., A, B, C, D, E, and F depending on the levels of physicochemical parameters in the water samples. The proposed classification system was applied to nine villages in Kadi Taluka, Mehsana district of Gujarat. The water samples were collected from borewells, lakes, Narmada Canal, and sewerage systems and were analyzed as per APHA and IS methods. It was observed that most of the physicochemical parameters of Narmada Canal and borewell water fell under class A, thus making them most suitable for drinking. Further, a health camp conducted at Karannagar village, Mehsana revealed no incidents of any waterborne diseases. However, there were certain incidents of kidney stones and joint pain in few villages due to high levels of TDS. Toxic metal analysis in all the water sources revealed low to undetectable concentration of toxic metals such as lead, arsenic, mercury, and cadmium in all the water sources. It is also recommended that the regular treatment of the Narmada Canal water be continued to maintain its excellent quality.

Fabrication routes for one-dimensional nanostructures via block copolymers.

Nanotechnology is the field which deals with fabrication of materials with dimensions in the nanometer range by manipulating atoms and molecules. Various synthesis routes exist for the one, two and three dimensional nanostructures. Recent advancements in nanotechnology have enabled the usage of block copolymers for the synthesis of such nanostructures. Block copolymers are versatile polymers with unique properties and come in many types and shapes. Their properties are highly dependent on the blocks of the copolymers, thus allowing easy tunability of its properties. This review briefly focusses on the use of block copolymers for synthesizing one-dimensional nanostructures especially nanowires, nanorods, nanoribbons and nanofibers. Template based, lithographic, and solution based approaches are common approaches in the synthesis of nanowires, nanorods, nanoribbons, and nanofibers. Synthesis of metal, metal oxides, metal oxalates, polymer, and graphene one dimensional nanostructures using block copolymers have been discussed as well.

Multifarious applications of atomic force microscopy in forensic science investigations.

Forensic science is a wide field comprising of several subspecialties and uses methods derived from natural sciences for finding criminals and other evidence valid in a legal court. A relatively new area; Nano-forensics brings a new era of investigation in forensic science in which instantaneous results can be produced that determine various agents such as explosive gasses, biological agents and residues in different crime scenes and terrorist activity investigations. This can be achieved by applying Nanotechnology and its associated characterization techniques in forensic sciences. Several characterization techniques exist in Nanotechnology and nano-analysis is one such technique that is used in forensic science which includes Electron microscopes (EM) like Transmission (TEM) and Scanning (SEM), Raman microscopy (Micro -Raman) and Scanning Probe Microscopes (SPMs) like Atomic Force Microscope (AFM). Atomic force microscopy enables surface characterization of different materials by examining their morphology and mechanical properties. Materials that are immeasurable such as hair, body fluids, textile fibers, documents, polymers, pressure sensitive adhesives (PSAs), etc. are often encountered during forensic investigations. This review article will mainly focus on the use of AFM in the examination of different evidence such as blood stains, forged documents, human hair samples, ammunitions, explosives, and other such applications in the field of Forensic Science.