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Food adulteration is a primary global concern for public health, especially in developing countries, due to the lack of monitoring and appropriate policy developments and implementations. Synthetic colors and dyes are used to enhance the appearance of food products. Metanil Yellow (MY), a non-permitted, toxic, chief additive adulterant is majorly used in sweets, pulses, and turmeric in India owing to its color that ranges from yellow to orange. Owing to this, we have assessed the presence of MY in sweets like “jalebi” and “laddu” from branded and local vendors. We present a method to isolate the additive from the sweets with the help of acetic acid, followed by screening through colorimetric assay. The chemical characterization of MY was conducted using a multi-plate ultraviolet–visible (UV–Vis) spectrophotometer and attenuated total reflectance–Fourier transform infrared spectroscopy (ATR–FTIR). The appearance of magenta/pink color indicates the presence of MY in the chemical spot test. Also, thin-layer chromatography (TLC) was applied to validate the presence of this adulterant by comparing the peaks of reference (MY) with the extracted samples. TLC of food color extracted from the samples is an easy, efficient, and cost-effective method to detect toxic adulterants like MY. Our study demonstrates a simple food color extraction procedure, with easy and sensitive chemical assays, for the detection of MY in sweets. It also offers reasonable sensitivity and can be used to screen large numbers of samples in a short time.

Summary The teeth are considered as a reliable indicator of age and provide several parameters for age estimation. Age estimation from dental radiographs is a non-destructive and straightforward method to obtain information. This preliminary study aimed to establish a relationship between chronological age and the tooth/pulp area ratio in a central Indian population. The digital dental X-ray- OPGs of 46 randomly selected consenting subjects belonging to the age group 18 to 60 years were examined. The tooth area and pulp area of upper maxillary right permanent canine were calculated. A Graph was also plotted on the scattered points to get a linear trend line and equation of the relationship between chronological age and tooth/pulp area ratio. Statistical analysis shows a significant strong positive correlation (R2= 0.99) between age and tooth /pulp area ratio. Linear Regression equation was derived for estimation of age, i.e., y = 6.6554x - 22.578 (where y is the estimated age and x is the tooth-pulp area ratio). The estimated age was accurate up to ± 2 years of the actual age. The result of this preliminary study shows that the tooth/pulp area ratio of the canine may serve as a reliable tool for estimation of age.

Microfluidics is the technology or system wherein the behavior of fluids' is studied onto a miniaturized device composed of chambers and tunnels. In biological and biomedical sciences, microfluidic technology/system or device serves as an ultra-high-output approach capable of detecting and separating the biomolecules present even in trace quantities. Given the essential role of protein, the identification and quantification of proteins help understand the various living systems' biological function regulation. Microfluidics has enormous potential to enable biological investigation at the cellular and molecular level and maybe a fair substitution of the sophisticated instruments/equipment used for proteomics, genomics, and metabolomics analysis. The current advancement in microfluidic systems' development is achieving momentum and opening new avenues in developing innovative and hybrid methodologies/technologies. This chapter attempts to expound the micro/nanofluidic systems/devices for their wide-ranging application to detect and separate protein. It covers microfluidic chip electrophoresis, microchip gel electrophoresis, and nanofluidic systems as protein separation systems, while methods such as spectrophotometric, mass spectrometry, electrochemical detection, magneto-resistive sensors and dynamic light scattering (DLS) are discussed as proteins' detection system.

Krupa Kansara, Pal Patel, Ritesh K Shukla, Alok Pandya, Rishi Shanker, Ashutosh Kumar, Alok Dhawan Institute of Life Sciences, School of Science and Technology, Ahmedabad University, Ahmedabad, Gujarat, India Abstract: Over the last decade, there has been growing interest in developing novel nanoparticles (NPs) for biomedical applications. A safe-by-design approach was used in this study to synthesize biocompatible iron oxide NPs. The size of the particles obtained was ~100 nm. Although these NPs were significantly (P

Document dating is one of the most challenging areas in the field of questioned document examination. Determination of age of document becomes of prime importance in the cases involving the document having historical value, or the document in question bearing a date, that is disputed. The dating of documents can be done by focusing on different aspects of a document, i.e., dating through paper, through inks, through a sequence of intersecting lines, through handwriting, etc. This article furnishes a broad overview of the dating documents techniques and instruments based on the various methods and their possible applications and limitations. The document dating may be performed using either or a combination of static, dynamic and supplementary approaches. The static approach includes time tags, chemical composition, elemental profiling. The dynamic approach includes ink, paper and toner ageing. The supplementary methods comprise accelerated ageing techniques, chemometric approaches, constructing the chronology of documents, analyzing luminescent components, radiocarbon dating and nanotechnology-based approaches. This article brings to fore the utilization of the different facets of the document for dating purposes. It presents the summarized form of the different methods and techniques, including some less focused ones.

Little is known of the effects of nanoparticles in human systems, let alone in diseased individuals and nanotechnology has preceded nanotoxicology. Therefore, the effects of titanium dioxide (TiO2) nanoparticles in peripheral blood lymphocytes from patients with respiratory diseases [lung cancer, chronic obstructive pulmonary disease (COPD) and asthma] were compared with those in healthy Individuals, to determine differences in sensitivity to nanochemical insult. The Comet assay was performed according to recommended guidelines. The micronucleus assay and ras oncoprotein detection were conducted according to published standard methods. The results showed statistically significant concentration-dependent genotoxic effects of TiO2 NPs in both respiratory patient and control groups in the Comet assay. The TiO2 NPs caused DNA damage in a concentration dependent manner in both groups (respiratory and healthy controls) with the exception of the lowest TiO2 concentration (10 μg/ml) which did not induce significant damage in healthy controls (n.s). When OTM data were used to compare the whole patient group and the control group, the patient group had more DNA damage (p > 0.001) with the exception of 10 μg/ml of TiO2 that caused less significant damage to patient lymphocytes (p < 0.05). Similarly, there was an increase in the pattern of cytogenetic damage measured in the MN assay without statistical significance except when compared to the negative control of healthy individuals. Furthermore, when modulation of ras p21 expression was investigated, regardless of TiO2 treatment, only lung cancer and COPD patients expressed measurable ras p21 levels. Results were achieved in the absence of cytotoxicity.

Postmortem interval (PMI) estimation is a recurring problem in the field of forensic medicine. Conventional methods are effective but are insufficient to estimate accurate and precise time of death or PMI. In addition, degradation of biological samples is another major problem in forensic science which affects the investigation process and misleads the result. Some previous studies reported that DNA fragmentation has strong correlation with PMI. DNA fragmentation increased with prolonged PMI. Comet assay is a rapid sensitive, versatile, reliable and cost effective technique that is specifically used for qualitative and quantitative estimation of nuclear DNA fragmentation. Due to this attribute, comet assay can help to estimate accurate and precise time of death for some extent that is for early PMI estimation. In addition, two confounding factors are responsible for DNA fragmentation: (1) micro-organism; (2) environmental condition. Here, comet assay plays a dual role: (1) partially degraded samples get repaired using repair enzyme; (2) accurate time since deposition can be measured without using repair enzyme. Furthermore, this assay can also help to identify potential exposures of environmental-released chemicals/toxicants and its deleterious effects on human population. In this way, comet assay shows its versatile applications that could be useful for forensic investigation. Therefore, with the help of this review, an attempt was made to explore the versatility of comet assay technique for forensic applications and its future perspective.

Forensic DNA analysis may be defined as the process of identification and individualisation of biological evidence for legal proceedings using DNA technology. It is used in both criminal and in civil cases. Due to dissimilarity in every crime scene and unpredictability of DNA samples collected from the crime scene, the analysis in Forensic Science Laboratories is a tough job for the DNA analyst/expert. This chapter briefly discusses the various aspects of ‘quality control’ in DNA forensics. The quality control (QC) in DNA testing is not limited to the quality of the testing laboratory but has to be taken into consideration during every step of the investigation. The chain of custody should be maintained throughout the process. The path of the DNA evidence from the crime scene to the courtroom is quite lengthy and intricate. Different QCs along the whole process shall assist in providing justice by eliminating the chances of errors and thus increasing the admissibility in the court of law.

The new pedagogical approach of teaching and learning provides better deliverables by the teachers and better understanding and student engagement. In this order, a course was designed on Forensic Science for undergrad students from interdisciplinary background. Six pedagogies were used in this course with the aim to develop creativity, critical and logical thinking, practical learning, social accountability and research aptitude among the students. The main reasons for selecting these students were to avoid influencing the learning outcome due to their prior knowledge and observing the actual impact of the pedagogical learning. The suggested approach may be helpful in reducing the theoretical and practical gap in forensic science education. Besides, this teaching and learning approach may open a new avenue of forensic research and may result in a paradigm shift.

Nanoparticles possess size-dependent chemical and physical characteristics that enable interesting and correlated approaches for dealing with fundamental biological molecules. Despite the significant development of nanoscience, interactions of nanoscale objects with living systems is less known. When a nanoparticle (NP) encounters a biological fluid, biomolecules spontaneously form adsorption layers around the NP, called a “protein corona” (PC). The corona's composition depends on the time-dependent environmental conditions, which determines the NP's fate within living organisms. The PC consists of two poorly delimited layers, known as the “hard corona” (HC) and “soft corona” (SC), which is affected by the complexity of the environment and the protein–surface equilibrium formed during in vivo blood circulation. This chapter is focused on the investigation of the corona formation of adsorbed proteins around nanoparticles depending on the type of characterization technique. Protein corona–NP complexes are further characterized by integrating information on morphology and also on the structure/composition of the PC. Thus, multi-disciplinary approaches are highlighted in order to obtain much more information about the PC and its properties to fully understand the real impact of the PC on nanoparticles' surface and their various therapeutics applications.

Little is known of the effects of nanoparticles in human systems, let alone in diseased individuals and nanotechnology has preceded nanotoxicology. Therefore, the effects of titanium dioxide (TiO2) nanoparticles in peripheral blood lymphocytes from patients with respiratory diseases [lung cancer, chronic obstructive pulmonary disease (COPD) and asthma] were compared with those in healthy Individuals, to determine differences in sensitivity to nanochemical insult. The Comet assay was performed according to recommended guidelines. The micronucleus assay and ras oncoprotein detection were conducted according to published standard methods. The results showed statistically significant concentration-dependent genotoxic effects of TiO2 NPs in both respiratory patient and control groups in the Comet assay. The TiO2 NPs caused DNA damage in a concentration dependent manner in both groups (respiratory and healthy controls) with the exception of the lowest TiO2 concentration (10 μg/ml) which did not induce significant damage in healthy controls (n.s). When OTM data were used to compare the whole patient group and the control group, the patient group had more DNA damage (p0.001) with the exception of 10 μg/ml of TiO2 that caused less significant damage to patient lymphocytes (p0.05). Similarly, there was an increase in the pattern of cytogenetic damage measured in the MN assay without statistical significance except when compared to the negative control of healthy individuals. Furthermore, when modulation of ras p21 expression was investigated, regardless of TiO2 treatment, only lung cancer and COPD patients expressed measurable ras p21 levels. Results were achieved in the absence of cytotoxicity.

Pal Patel, Krupa Kansara, Ragini Singh, Ritesh K Shukla, Sanjay Singh, Alok Dhawan, Ashutosh Kumar Division of Biological and Life Sciences (Formerly Institute of Life Sciences), School of Arts and Sciences, Ahmedabad University, Ahmedabad, Gujarat, India Abstract: Overproduction of free radicals contributes to oxidative stress and inflammation leading to various disease conditions. Cerium oxide nanoparticles (nanoceria) have been shown to scavenge free radicals and have the potential for being used as a therapeutic agent in disease conditions. Therefore, in the present study, human monocytic leukemia cells (THP-1) were used as a model to evaluate the uptake and free radical scavenging activity of nanoceria. Our data showed a significant (P

Cellulose paper based multifunctional nanoplatform shows great promise towards molecular sensing and diagnostics application due to their sustainability, biocompatibility, affordability, environmental appeal and broad chemical modification capabilities. Herein, we have effectively synthesized plasmonic silver-cellulose nanocomposite (SCN) using complete green and in situ approach using the hydroxyl groups of cellulose paper acting as the reducing agent and stabilizing agent. The fabricated SCN were investigated and characterized by SEM, UV-Vis, DLS, PXRD and EDX. The important influencing parameters such as temperature and pH were optimized during the fabrication of SCN. Besides, this SCN functionalized with 3-aminopropyltriethoxysilane and has been exploited for monitoring of fluoride ion from water samples with distinguishing F- from a wide range of environmental prevalent ions. These remarkable properties of SCN have been used as rapid, portable test panel which could be simple, lightweight and disposable.

Time since death (TSD) estimation is a crucial issue in death investigation. In majority of homicide/suicide cases deceased body recovered within the first 48 h, therefore, it is critically important to determine the time of death quickly and precisely. In the present scenario, TSD estimation still remains difficult even for experienced pathologists undertaken with extreme caution. After death numerous factors may be of cadaveric or environmental origin can influence the ‘normal’ rate of postmortem changes. Therefore, it could be more difficult to estimate longer TSD. However, these environmental influencing factors can also effect on DNA in the form of degradation, which start after 1–2 h of death. This DNA degradation could be work as molecular clock which help to estimate early TSD. Single-cell gel electrophoresis (SCGE), also known as the Comet assay, is the technique by which DNA degradation can be visualized and measured qualitatively as well as quantitatively. Using this assay not only early TSD estimated but many other challenges such as time since deposition of biological fluids, repair of genetic material from degraded biological sample could also be resolved. With the help of this paper an attempt was made to introduce a well-known cytogenetic technique that is SCGE assay, which could be a versatile technique for forensic science.

TiO2 nanoparticles (NPs) have the second highest global annual production (� 3000 tons) among the metal-containing NPs. These NPs are used as photocatalysts for bacterial disinfection, and in various other consumer products including sunscreen, food packaging, therapeutics, biosensors, surface cleaning agents, and others. Humans are exposed to these NPs during synthesis (laboratory), manufacture (industry), and use (consumer products, devices, medicines, etc.), as well as through environmental exposures (disposal). Hence, there is great concern regarding the health effects caused by exposure to NPs and, in particular, to TiO2 NPs. In the present study, the genotoxic potential of TiO2 NPs in A549 cells was examined, focusing on their potential to induce ROS, different types of DNA damage, and cell cycle arrest. We show that TiO2 NPs can induce DNA damage and a corresponding increase in micronucleus frequency, as evident from the comet and cytokinesis-block micronucleus assays. We demonstrate that DNA damage may be attributed to increased oxidative stress and ROS generation. Furthermore, genomic and proteomic analyses showed increased expression of ATM, P53, and CdC-2 and decreased expression of ATR, H2AX, and Cyclin B1 in A549 cells, suggesting induction of DNA double strand breaks. The occurrence of double strand breaks was correlated with cell cycle arrest in G2/M phase. Overall, the results indicate the potential for genotoxicity following exposure to these TiO2 NPs, suggesting that use should be carefully monitored. Environ. Mol. Mutagen. 00:000– 000, 2014. V C 2014 Wiley Periodicals, Inc.

The rapid advancement in nanotechnology sets new paradigms in science and technology, but simultaneously increased apprehen- sions about the health risks of nano-objects. Recently, various types of nanoparticles used in several areas of forensic including paint, inks, security document and to develop the latent fingerprint. Objective: Despite bright outlooks of nanoparticles used in various fields of forensic science, an increasing occupational as well as laboratory exposure of nanoparticles to workers and lab personnel, respectively, may lead to significant adverse health effects in the form of serious diseases. Conclusion: Therefore, in this review, an attempt was made to discuss the positive and negative consequences of nanoparticles, to resolve their adverse effects which make them safer for forensic applications.

The in vivo mammalian alkaline Comet assay is used for assessing the DNA-damaging potential of chemicals in cells and tissues of rats and mice. The assay has been adopted by the OECD, as a second-tier test, in the standard battery of genotoxicity tests. This chapter outlines the protocol followed for performing the in vivo Comet assay in cells of blood and different organs e.g. liver, kidney, brain, spleen and bone marrow of mouse.

Present study examines biological efiects of 2.45GHz microwave radiation in Parkes strain mice. Forty-day-old mice were exposed to CW (continuous wave) microwave radiation (2h/day for 30 days). Locomotor activity was recorded on running wheel for 12 days prior to microwave exposure (pre-exposure), 7 days during the flrst week of exposure (short-term exposure) and another 7-day spell during the last week of the 30-day exposure period (long-term exposure). Morris water maze test was performed from 17th to 22nd day of exposure. At the termination of the exposure, blood was processed for hematological parameters, brain for comet assay, epididymis for sperm count and motility and serum for SGOT (serum glutamate oxaloacetate transaminase) and SGPT (serum glutamate

At present, more than 20 countries worldwide are manufacturing and marketing different varieties of nanotech-based consumer products of which cosmetics form the largest category. Due to the extremely small size of the nanoparticles (NPs) being used, there is a concern that they may interact directly with macromolecules such as DNA. The present study was aimed to assess the genotoxicity of zinc oxide (ZnO) NPs, one of the widely used ingredients of cosmetics, and other dermatological preparations in human epidermal cell line (A431). A reduction in cell viability as a function of both NP concentration as well as exposure time was observed. ZnO NPs demonstrated a DNA damaging potential as evident from an increased Olive tail moment (OTM) of 2.13 +/- 0.12 (0.8 g/ml) compared to control 1.37 +/- 0.12 in the Comet assay after an exposure of 6 h. ZnO NPs were also found to induce oxidative stress in cells indicated by depletion of glutathione (59% and 51%); catalase (64% and 55%) and superoxide dismutase (72% and 75%) at 0.8 and 0.08 g/ml respectively. Our data demonstrates that ZnO NPs even at low concentrations possess a genotoxic potential in human epidermal cells which may be mediated through lipid peroxidation and oxidative stress. Hence, caution should be taken in their use in dermatological preparations as well as while handling.

Nanotechnology, the manipulation of matter at the atomic and molecular level to form novel materials with unusually diverse and unique properties, is a quickly expanding area of research with immense potential in several fields, ranging from health care to production and physical science. In forensic science it promises to revolutionize the applicability of micro-fluidic systems in post-polymerase chain reaction (PCR) quantification, DNA extraction media, fingerprint visualization using nano-powder. In general, Forensic Nanotechnology will transform the bulky instruments into small chip-based platforms, and shorten analysis methods to make investigations, sensitive, timely, and applicable.

TiO2 nanoparticles (NPs) have the second highest global annual production (∼3000 tons) among the metal-containing NPs. These NPs are used as photocatalysts for bacterial disinfection, and in various other consumer products including sunscreen, food packaging, therapeutics, biosensors, surface cleaning agents, and others. Humans are exposed to these NPs during synthesis (laboratory), manufacture (industry), and use (consumer products, devices, medicines, etc.), as well as through environmental exposures (disposal). Hence, there is great concern regarding the health effects caused by exposure to NPs and, in particular, to TiO2 NPs. In the present study, the genotoxic potential of TiO2 NPs in A549 cells was examined, focusing on their potential to induce ROS, different types of DNA damage, and cell cycle arrest. We show that TiO2 NPs can induce DNA damage and a corresponding increase in micronucleus frequency, as evident from the comet and cytokinesis-block micronucleus assays. We demonstrate that DNA damage may be attributed to increased oxidative stress and ROS generation. Furthermore, genomic and proteomic analyses showed increased expression of ATM, P53, and CdC-2 and decreased expression of ATR, H2AX, and Cyclin B1 in A549 cells, suggesting induction of DNA double strand breaks. The occurrence of double strand breaks was correlated with cell cycle arrest in G2/M phase. Overall, the results indicate the potential for genotoxicity following exposure to these TiO2 NPs, suggesting that use should be carefully monitored.

Background: The use of metal oxide nanoparticles (titanium dioxide) in consumer and industrial products improves their quality but also underscores the possible adverse effects to human and environmental health. Materials & methods: Mice were exposed orally for 14 consecutive days and analyzed for alteration in different hepatic enzymes, histopathological changes, oxidative stress, DNA damage, tumor suppressor and proapoptotic protein expression in liver cells. Results: We observed a significant alteration in the level of hepatic enzymes and liver histopathology at a dose of 100 mg/kg body weight. Significant oxidative DNA damage was observed in liver cells, which could be attributed to oxidative stress. In addition, the increased expression of p53, BAX, caspase-3 and -9 proteins and decreased expression of antiapoptotic protein Bcl-2, suggest activation of the intrinsic pathway of apoptosis. Conclusion: High accumulation of titanium dioxide nanoparticles in the liver tissue would cause DNA damage and apoptosis through the intrinsic pathway. Original submitted 7 December 2012; Revised submitted 25 April 2013

The present experiment was designed to study the 2.45 GHz low-level microwave (MW) irradiation-induced stress response and its effect on implantation or pregnancy in female mice. Twelve-week-old mice were exposed to MW radiation (continuous wave for 2 h/day for 45 days, frequency 2.45 GHz, power density=0.033549 mW/cm(2), and specific absorption rate=0.023023 W/kg). At the end of a total of 45 days of exposure, mice were sacrificed, implantation sites were monitored, blood was processed to study stress parameters (hemoglobin, RBC and WBC count, and neutrophil/lymphocyte (N/L) ratio), the brain was processed for comet assay, and plasma was used for nitric oxide (NO), progesterone and estradiol estimation. Reactive oxygen species (ROS) and the activities of ROS-scavenging enzymes- superoxide dismutase, catalase, and glutathione peroxidase-were determined in the liver, kidney and ovary. We observed that implantation sites were affected significantly in MW-irradiated mice as compared to control. Further, in addition to a significant increase in ROS, hemoglobin (p

Titanium dioxide nanoparticles (TiO(2) NPs), widely used in consumer products, paints, pharmaceutical preparations and so on, have been shown to induce cytotoxicity, genotoxicity and carcinogenic responses in vitro and in vivo. The present study revealed that TiO(2) NPs induce significant (p0.05) oxidative DNA damage by the Fpg-Comet assay even at 1 µg/ml concentration. A corresponding increase in the micronucleus frequency was also observed. This could be attributed to the reduced glutathione levels with concomitant increase in lipid peroxidation and reactive oxygen species generation. Furthermore, immunoblot analysis revealed an increased expression of p53, BAX, Cyto-c, Apaf-1, caspase-9 and caspase-3 and decreased the level of Bcl-2 thereby indicating that apoptosis induced by TiO(2) NPs occurs via the caspase-dependent pathway. This study systematically shows that TiO(2) NPs induce DNA damage and cause apoptosis in HepG2 cells even at very low concentrations. Hence the use of such nanoparticles should be carefully monitored.

Metal oxide nanoparticles such as TiO2 (100 nm) are used in lotions and sunscreens. Toxicity studies so far have reported the use of TiO2 NPs with size100 nm as determined by dynamic light scattering (DLS) technique. We used non-reactive chemical agents such as propylene glycol (PG), glycerol (G), ethylene glycol (EG) to prevent aggregation and maintain NPs in monodispersed state closer to the reported TEM size. The lowest concentration of PG (0.1%) along with complete culture media (RPMI 1640) showed mean hydrodynamic diameter of TiO2 NPs as 33.71 nm measured by DLS. The present study demonstrates a method to prepare stable TiO2 NPs in culture media for toxicity assessment. This is a significant contribution as the biological properties of NPs vary considerably with decrease in size.

Titanium dioxide nanoparticles (TiO2 NPs) are the most commonly used metal oxide NPs in various industrial and commercial products. The present study has demonstrated a significant cellular uptake of TiO2 NPs in the human keratinocyte cells (HaCaT) using transmission electron microscopy and flow cytometry. The data exhibited a significant (p < 0.05) concentration dependent decrease in cell viability and glutathione with concomitant increase in lipid peroxidation and reactive oxygen species. The increased oxidative stress further leads to apoptosis after 48 h of exposure. Our study demonstrates oxidative stress mediated apoptosis in human keratinocyte cells exposed to TiO2 NPs.

Titanium dioxide nanoparticles (TiO(2) NPs) are among the top five NPs used in consumer products, paints and pharmaceutical preparations. Since, exposure to such nanoparticles is mainly through the skin and inhalation, the present study was conducted in the human epidermal cells (A431). A mild cytotoxic response of TiO(2) NPs was observed as evident by the MTT and NR uptake assays after 48 h of exposure. However, a statistically significant (p

Graphite nanomaterials such as thermally exfoliated graphite oxide (GO) are versatile in many applications. However, little is known about its effects on biological systems. In this study we characrerized the GO using dynamic light scattering (DLS) along with the toxicological aspects related to cytotoxicity and apoptosis in normal human lung cells (BEAS-2B). A significant concentration and time dependent decrease in cell viability was observed at different concentrations (10-100 microg/ml) by the MTT assay after 24 and 48 h of exposure and significant increase of early and late apoptotic cells was observed as compared to control cells. Our study demonstrates that GO induces cytotoxicity and apoptosis in human lung cells.

Background Engineered nanoparticles (ENPs) such as TiO2 are widely used in products such as cosmetics, clothing, food packaging, drug delivery systems, etc. due to their unique physicochemical properties. This has increased the liklihood of ENP exposure in humans. As the ENPs are having small size and high diffusion coefficient, they can migrate rapidly in the air. Therefore, inhalation is considered to be the primary route of exposure to such ENPs. Hence, in the present study an attempt was made to assess the potential toxicological effects of TiO2 NPs in human alveolar cell line (A549).

Background Due to high surface to volume ratio and other unique properties, nanomaterials interact within living system (cells, tissues, organisms) significantly different. Therefore, developing a rational basis for investigation and understanding about how these nanomaterials interact with living system is still a fundamental challenge. Further, it has been well documented that nanomaterials get coated by the proteins present in their surrounding thus constructing a “protein corona”. This event also plays a major role in determining the interaction of nanomaterials with cells/tissues. Therefore, to probe this we have chosen BSA coated gold nanoparticles (AuNPs) as a model system to study the interaction with a mammalian lung cell culture model system.

Background Cerium oxide nanoparticles (CeNPs) have shown promise as catalytic antioxidants in cell culture and animal models due to its superoxide dismutase and catalase mimetic activities. CeNPs can exist in +3 and +4 oxidation states, which have been suggested as the mechanism behind the free radical scavenging activity. It has also been shown that unique crystal structure of CeNPs with surface oxygen defects promote the shuffling between the +3 and +4 oxidation states that help in eliminating the free radicals. This activity of CeNPs has been suggested as the mechanism, at least in part, behind increase in cellular longevity and decrease in the toxic insults in mammalian cells/tissues. Further, the uniform distribution of CeNPs, upon cellular uptake, within the cells could prevent the accumulation of reactive oxygen species in the cells.

A facile synthesis to fabricate HAp–titania scaffolds with different morphological features has been presented. The hydrothermal approach explored for HAp growth leads to the formation of HAp coating onto titania substrate with distinct morphological features such as cauliflower, urchin, porous nanofibres network, nanorods, etc. under different reaction microenvironments. The XRD analysis done for all HAp–titania scaffold samples revealed the formation of hydroxyapatite phase. Furthermore, the detailed FTIR, SAED and EDS analysis performed confirmed the formation of hydroxyapatite. The addition of H2O2 to the reaction mixture led to the high degree of self-assembly of the formed nanosheets into urchin or consolidated sphere like structures when NaOH or KOH was used in hydrothermal reaction, respectively. The detailed TEM analysis reveals that the formation of such HAp structures takes place by (i) formation of localized corrosion sites on titanium substrate with NaOH/KOH and (ii) the subsequent recrystallization of HAp sol onto the corrosion sites which act as nucleation site. The Tafel plot measurements and MTT assay test indicate that the HAp–titania scaffold samples are corrosion resistance as compared to bare titanium foil and are biocompatible. The structural characterization, growth mechanism, corrosion behaviour in SBF medium and cellular biocompatibility of these scaffold samples are discussed in detail.