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Objective: The objective of the study is to know type of hypertension affecting pregnant women and impact on perinatal outcome. Subject and Methods: This is a prospective cohort study; 120 women with hypertensive disorders of pregnancy (HDP) at gestation ≥28 weeks who delivered in our institute were enrolled. Sociodemography, gestational age, mode of delivery, APGAR, birth weight, fetal growth restriction (FGR), and perinatal outcome were recorded. Mean ± standard deviation or proportions, analysis of variance, Chi-square test, and odds ratio were used for statistical analysis. Results: Preeclampsia (PE) was most prevalent hypertensive disorder of pregnancy (44.2%), followed by eclampsia (27.50%), gestational hypertension (23.3%), and chronic hypertension (CH) (5.0%). In PE group, 61.8% had FGR, 65.5% newborns were preterm, 74.6% had low birth weight, and 54.1% needed neonatal intensive care unit (NICU) admission. In eclampsia group, 42.9% had fetal growth restriction, 65.7% preterm, 80% low birth weight, and 78.6% NICU admission. PE women delivered more fetal growth-restricted babies with odd ratio of 2.37 (95% confidence interval [CI]: 1.15, 4.9) and at lower gestation with odd ratio of 2.00 (95% CI: 0.95, 4.21). Eclampsia group had more newborn with low APGAR 1 min, NICU admissions, and those requiring ventilator with odds ratio of 3.10 (95% CI: 1.37, 7.03), 4.48 (95% CI: 1.64, 12.24), and 4.09 (95% CI: 1.6, 10.46), respectively. Perinatal mortality was 10, 9, and 2 in eclampsia, PE, and gestational hypertension groups, respectively, with overall rate of 16.9%. PE and eclampsia comprised 71.70% of HDP but contributed 90.5% of all perinatal deaths. Conclusion: Preeclampsia-eclampsia is associated with increased risk of adverse perinatal outcomes as compared to gestational and CH, necessitating screening, vigilant antenatal care, timely intervention, and referral.

Metal free heterojunctions have shown promising applicability as potential photocatalyst materials. Like the commonly explored metal-non metal heterojunctions, semiconductor-semiconductor junctions are also capable of facilitating charge separation and improved lifetimes, leading to augmented surface reaction efficacy. However, unlike the metal carrying heterojunctions, they are much economical and easier to fabricate and tune. Through this study, we present a facile one step hydrothermal route to synthesize CuO-Cu2O nanorods/TiO2 nanoparticles heterostructures (CTHS) with their potential application as a low cost photocatalytic alternative. The average size of the synthesized heterojunction components, as estimated from transmission electron microscopy (TEM) evaluation was 13 and 5 nm respectively for the nanorod length and width, while the functionalizing TiO2 nanoparticles were averaged around 10 nm. Heterojunction formation was confirmed using Raman spectroscopy, X-ray diffraction, high resolution TEM, and elemental mapping. X-ray photoelectron spectroscopy data marked with presence of Cu+ and Cu+2 state of CuO in CuXO-TiO2 also supported junction formation. Optical characteristics of the heterojunction were studied using UV–vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. Compared to TiO2 nanoparticles, CTHS exhibited superior sunlight-induced photodegradation activity. CuXO/TiO2 heterojunction could also remediate toxic waste water containing model antibiotic residue (Oxytetracycline hydrochloride, 0.4 mg/mL) and organic pollutant (methylene blue, 10 µM) in 20 and 60 min respectively. Ultra-fast degradation using a nonmetal heterojunction nanohybrid, like ours, finds negligible mention in literature. Improved visible light absorption and reduction in recombination rate for CuXO-TiO2 nanohybrids were ascribed as major contributing factors towards their enhanced photocatalytic potential. The charge separation mechanism for nanohybrids has been studied and elaborated in detail.

Sustainability drives modern technology. Practices ensuring efficient resource utilization, guided resource handling and promotion of negative ecological footprint befittingly implicate “growth”. With manufacturing being one of the major contributing sectors to a nation's economy, adopting greener fabrication processes, the production of cleaner energy and the development of efficient products are important to achieve technological translation. Herein, a bi-functional hybrid (semiconductor–metal) system comprising zinc oxide nano leaves uniformly decorated with gold nano islands was synthesized using a one-step, room temperature biosynthetic reduction strategy. Being a one-step process, the number of reaction reagents and auxiliary byproducts was limited while material engineering ensured efficient product performance derived from coexistence of localized surface plasmon, semiconduction and their synergistic interaction. Detailed characterization of the as synthesized hybrid system concludes presence of defect states, crystalline nature, engineered band gap, pertinent chemical elemental state and interfacial charge distribution features. The hybrid nanostructures show strong surface-enhanced Raman scattering (SERS) characteristics for model R6G molecules (LOD: 10−10 M). Marked with the presence of symmetric and non-totally symmetric Raman vibrations, the role of electromagnetic and chemical enhancement was equally attributed to improved signal strengths. Contribution from charge transfer was verified using off resonance measurements and by studying the photolytic behavior of the nano-hybrid system. The self-cleaning feature of the nanohybrid was tested against a model bacterial contaminant S. aureus, which was killed with 100% efficiency using ∼60 μg ml−1 under natural sunlight.

We present hydrothermal fabrication of hydroxyl group-rich mixed-phase TiO2 nanoflowers (surface area ~ 252 m2/g) (MTNF) and their tremendous sunlight-induced photodegradation nature for methylene blue (MB), methyl orange (MO), rhodamine 6G (R6G), and oxytetracycline hydrochloride (OTC-HCl) molecules. The morphology of MTNF has been confirmed through the transmission electron microscope and scanning electron microscope studies. Microscopy studies reveal that each flower-like nanostructures formed by the assembly of nanoflakes. X-ray diffraction and Raman studies confirm the presence of mixed (anatase/rutile) phase of TiO2. The optical behavior of MTNF is explored by the UV-visible diffuse reflectance spectroscopy (UV-DRS) and photoluminescence spectroscopy (PL). Urbach energy calculation indicates the appearance of oxygen-related defects which are further assured by the PL studies. Existence of the hydroxyl group over the surface of MTNF is confirmed through Fourier transform infrared spectroscopy studies. Adsorption study results show the higher tendency of MTNF to adsorb the MB dye molecules as compared to R6G and MO dye molecules due to the presence of hydroxyl group and effective high surface area. Sunlight-driven photodegradation activity of MTNF was demonstrated by the decoloration of MB, MO, R6G, and OTC-HCl solution. Hydroxyl group functionalized MTNF with effective surface area decomposes the 16 µM MB, 10 µM MO, 10 µM R6G, and 0.5 mg/mL OTC-HCl molecules in just 12 min, 40 min, 30 min, and 60 min, respectively. Sunlight-induced photodegradation activity of MTNF can be attributed to the combined feature of hydroxyl radicals and synergistic effects in the TiO2 nanoflower-like structures.

The shape-anisotropic metal nanoparticles support large surface plasmon resonance (SPR) wavelength tuning and higher intrinsic electromagnetic hot spots for excellent surface-enhanced Raman spectroscopy (SERS) performance. Here, two shape-anisotropic nanostructures, silver nanocubes and nanowires with sharp features and high yield, are synthesized using the polyol reduction method. Finite-difference time-domain (FDTD) simulations are performed to understand the origin of the SPR peaks in the absorption spectra and for optimization of excitation wavelengths for large near-field enhancement. Silver nanocubes and nanowires exhibit broad plasmon resonances over the visible region of the electromagnetic spectrum with maxima around 498 nm and 410 nm, respectively. The SERS activity of nanocubes and nanowires are investigated for three molecules of different Raman activity. The SERS spectra show higher activity for nanocubes and ultra-low molecular detection (10−15 M) capability of the fabricated substrates for rhodamine B (RhB) dye, p-aminothiophenol (PATP), and pesticide thiram. Relatively higher enhancement of some Raman modes is observed when excited with laser wavelength 532 nm indicating photo-induced charge transfer from metal to molecule.

Improvements in the charge transfer interface and efficient light utilization have proven to be essential parameters for the superior performance of heterostructure-based photocatalysis. In the present study, 2D MoS2 nanosheet-modified oxygen defect-rich anatase TiO2 nanostructures were developed by the hydrothermal method. Elemental mapping and transmission electron microscopy studies affirmed the functionalization of 2D MoS2 nanosheets with TiO2 nanoparticles. Raman spectroscopy and XRD studies confirmed the formation of the MoS2–TiO2 heterojunction. UV-DRS studies exhibited improved visible light absorption and significant bandgap narrowing in TiO2 nanostructures with the modification of 2D MoS2 nanosheets. PL results also displayed an improvement in the charge separation and reduction in the recombination rate in MoS2-modified TiO2. White light emission PL was achieved through modulation in the defect concentration of TiO2 with the attachment of MoS2 nanosheets. MoS2-modified TiO2 nanostructures showed remarkable photodegradation nature for methylene blue (MB) dye degradation under sunlight. The most efficient MoS2-modified TiO2 decomposed 98.3% of MB, 84.7% of oxytetracycline hydrochloride (OTC-HCl) and 80% of methyl orange (MO) molecule solution in just 12 minutes, 50 minutes and 30 minutes, respectively, under sunlight. The enhanced photolysis performance of MoS2–TiO2 nanohybrids can be ascribed to the efficient light utilization and synergistic effects among the MoS2 and defect-rich TiO2 nanoparticles.

Here, we carried out the sensing of nitro amine explosives through surface-enhanced Raman scattering (SERS) employing silver nanoparticle (Ag NP)-decorated reduced graphene oxide (rGO) nanocomposite substrate. In situ reduction process has been utilized to prepare the reduced graphene oxide–silver nanocomposite. The areal distribution and structural properties of Ag NPs have been studied. The fabricated nanocomposite was characterized using microscopic, spectroscopic and thermogravimetric methods. Moreover, the electrochemical properties of rGO–Ag nanocomposites were analysed using electrochemical methods. Raman spectra show the enhancement in the Raman signal of rGO-decorated Ag NPs with an intensity enhancement factor of 12.5 for D peak and 9 for G peak. The Ag NP-enriched rGO has also demonstrated strong SERS activity towards the detection of cyclotetramethylene tetranitramine and cyclotrimethylenetrinitramine up to 10−12 M as the limit of detection with SERS enhancement of 109. Thus, the synthesized nanocomposite shows potential applications for sensing of explosives.

We report trace level detection of tryptophan and adenine molecules over indium (In) and In@SiO2 core-shell nanostructures using ultraviolet surface-enhanced Raman spectroscopy (UV-SERS). The In nanostructure-based SERS substrates display highly stable and reproducible SERS spectra of tryptophan and adenine under 325 nm UV excitation. With 325 nm wavelength, intrinsic to the plasmon resonance wavelength of the In@SiO2 nanoparticles (NPs) and near the molecular absorption band, intensity enhancement factor of ~105 and an ultra-sensitive limit of detection (LOD) up to ~0.18 fM for tryptophan and ~0.05 fM for adenine have been achieved. The SERS enhancement exhibits sensitive to SiO2 shell thickness, i.e. to the distance of the probe molecule from the In core. Our results show that a ~2 nm thick SiO2 layer serves as an efficient protective layer for preventing Raman signal deterioration by oxidative degradation of In nanoparticles (NPs). Also, finite-difference-time-domain (FDTD) based simulations have been carried out to study the plasmonic response of indium and core-shell In@SiO2 NP, enhanced electric field distribution under 325 nm excitation wavelength to analyse the experimentally observed SERS spectra. The simulation results are in good agreement with the experimental observations supporting the strong plasmonic response of In NPs in the ultraviolet region.

In the current study, Au–TiO2 thin films were prepared on glass substrates through the combined approach of spin-coating thermal evaporation method. The decoration of Au nanoparticles on to TiO2 surface has been achieved by the thermal annealing process under Ar atmosphere. Au–TiO2 thin films with improved optical absorption and effective bandgap narrowing exhibits outstanding photodegradation activity and ultra-sensitivity towards surface-enhanced Raman spectroscopy (SERS) based detection of the organic molecules. The existence of Au nanoparticles on TiO2 nanostructures efficiently controls the rate of recombination consequently Au–TiO2 thin films show significantly improved sun-light induced photodegradation efficiency for methylene blue (MB) dye. Au–TiO2 thin films decomposed 5 µM MB dye solution in 40 min under sun light exposure (850 W/cm2). Au–TiO2 thin films also exhibit efficient detection capabilities for the two organic molecules rhodamine 6G (R6G) and methylene blue (MB) with the Raman intensity enhancement factors of the order of ~ 107. The observed excellent SERS sensitivity of Au–TiO2 thin films towards the pollutant molecules are ascribed to the contribution of charge transfer mechanism among TiO2 and dye molecules. Furthermore, the fabricated Au–TiO2 thin films were also evaluated for the multiplexed detection by simultaneously detecting the two analytes (MB and R6G) from their mixture with superior sensitivity. Au–TiO2 nanohybrids thin films with these tremendous applications can be further employed for different applications like solar cell, gas sensing, energy production, and water splitting.

In this paper, we report photoluminescence (PL) and surface-enhanced Raman spectroscopy of atomically thin molybdenum disulphide (MoS2) on SiO2/Si substrate grown by chemical vapor deposition. We investigated the impact of Ag and Au nanostructure on the surface of MoS2 film through PL and Raman spectrum. Apart from enhanced Raman scattering, a heavy fall in PL intensity was observed because of the charge transfer from MoS2 to the metal hybrid structure. To support this, the work function was estimated by Kelvin probe force microscopy, and it was found to be 4.27 eV on pristine MoS2 film and 4.75 eV and 4.86 eV with the use of Ag and Au nanostructures separately on MoS2 film. Furthermore, using one-dimensional Schrodinger–Poisson (1D-SP) simulations, the band diagram and carrier concentration of molybdenum disulphide before and after the metal contact has also been calculated. The change in work function and more than hundred times decrease in carrier concentration explains the quenching of PL intensity due to charge transfer. Moreover, the results indicate the enhancement in Raman intensity due to local surface plasmon resonance of Au and Ag nanoparticles.

Children 0-14 years constitute about 31.4% of Indian population, among whom the magnitude and risk factors of childhood injuries have not been adequately studied.To study the prevalence of and assess the factors associated with unintentional injuries among children aged 6 month - 18 years in various regions.This multi-centric, cross-sectional, community-based study was conducted at 11 sites across India. States included were Gujarat, Karnataka, Madhya Pradesh, Punjab, Sikkim, Tamil Nadu, Uttarakhand, and West Bengal between March, 2018 and September, 2020. A total of 2341 urban and rural households from each site were selected based on probability proportionate to size. The World Health Organization (WHO) child injury questionnaire adapted to the Indian settings was used after validation. Information on injuries was collected for previous 12 months. Definitions for types (road traffic accidents, falls, burns, poisoning, drowning, animal-related injuries) and severity of injuries was adapted from the WHO study. Information was elicited from parents/primary caregivers. Data were collected electronically, and handled with a management information system.In the 25751 households studied, there were 31020 children aged 6 months-18 years. A total of 1452 children (66.1% males) had 1535 unintentional injuries (excluding minor injuries) had occurred in the preceding one year. The overall prevalence of unintentional injuries excluding minor injuries was 4.7% (95% CI: 4.4-4.9). The commonest type of injury was fall-related (842, 54.8%) and the least common was drowning (3, 0.2%). Injuries in the home environment accounted for more than 50% of cases.The findings of the study provide inputs for developing a comprehensive child injury prevention policy in the country. Child safe school with age-appropriate measures, a safe home environment, and road safety measures for children should be a three-pronged approach in minimizing the number and the severity of child injuries both in urban and rural areas.

Visible light-sensitive photocatalytic systems have readily relied on metal oxide semiconductors' functionalization with plasmonic nanostructures to improve their activity. Here, we report a non-metal, visible light (sunlight) sensitive photocatalytic 2D-layered based nanohybrid system capable of efficient degradation of organic contaminants with huge efficiency. MoS2 nanoflowers decorated β-In2S3 nanosheets heterostructure hybrid has been prepared by using a facile hydrothermal method. 2D-layered-based semiconductor heterostructure (In2S3-MoS2) effectively improves the lifetime of the charge carriers by minimizing their rate of recombination, allowing enough time for surface reactions such as photocatalysis to take place. UV-DRS results reveal a significant improvement in the optical absorbance in the visible region. X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy results confirm the appearance of 2H-MoS2 and β-In2S3 in the grown heterostructures. Chemical mapping confirms uniform distribution of Mo, In, and S atoms in the heterostructure, affirming sample uniformity. Modified optical properties of In2S3-MoS2 heterostructure samples reveal efficient charge separation while incrementing the light absorption ability, indicative of its enhanced photocatalytic activity in solar light. The photocatalytic decomposition efficiency of the In2S3-MoS2 heterostructure is compared with pristine In2S3 nanosheets. For 8 minute exposure in sunlight, ca 97.67% degradation for methylene blue dye has been estimated for a sample load of 0.025 mg/ml. The improved photocatalytic degradation efficiency of the In2S3-MoS2 heterostructure is ascribed to its efficient charge separation mechanism.

Undernutrition and overnutrition pose a significant challenge in many developing countries, including India. While one of the millennium development goal was to eradicate poverty and hunger by 2015, leaving health service workers with a compounding dilemma of solving both undernutrition and overnutrition concurrently. Both undernutrition and overnutrition are linked with a range of adverse health conditions. The underweights are susceptible to poor maternal and infant health as well as childhood growth problems and compromised mental development, whereas obese are associated with chronic diseases as stroke, hypertension, cardiovascular diseases, type 2 diabetes, and certain forms of cancer. The prevalence of child undernutrition was 60% in 1990 which came to 40% in 2011. India still continues to have a larger share of stunted, underweight, and wasted children. The underweight rate was about 52% in 1992 and declined to 47% in 1998 and remained nearly almost same (46%) in 2005-2006. On the other hand, overnutrition is also becoming a major public health problem over the past several decades. Studies have shown an increase in overweight children and adults over the past 2 decades especially.

Metal free heterojunctions have shown promising applicability as potential photocatalyst materials. Like the commonly explored metal-non metal heterojunctions, semiconductor-semiconductor junctions are also capable of facilitating charge separation and improved lifetimes, leading to augmented surface reaction efficacy. However, unlike the metal carrying heterojunctions, they are much economical and easier to fabricate and tune. Through this study, we present a facile one step hydrothermal route to synthesize CuO-Cu

We have fabricated Ag–Au alloy nanocubes using the galvanic replacement of silver nanocubes by aqueous HAuCl4 and investigated their morphological, structural, compositional and optical properties. The inter-diffusion between silver and gold at 100 °C leads to the formation of Ag–Au alloy nanocubes with hollow interiors. A broad tuning of the surface plasmon resonance (SPR) wavelength from 624 nm to 920 nm is obtained with the varying volume of HAuCl4. When excited at wavelength 785 nm, the bimetallic Ag–Au nanocubes with pinholes exhibit two-fold Raman intensity enhancement compared to pristine Ag nanocubes. The surface-enhanced Raman spectroscopy (SERS) substrate prepared with Ag–Au alloy nanocubes shows high-intensity enhancement factor of 1.9 × 107 for 11.2 wt% Au content. The SERS-active Ag–Au alloy nanocubes substrates were exploited for the detection of two explosive molecules; p-nitrobenzoic acid (PNBA) and picric acid (PA). Remarkable detection sensitivity and ultra-low detection limit of 1.7 × 10–14 M for PNBA and 4.1 × 10–11 M for PA were obtained, demonstrating the very high SERS detection capabilities of the as-prepared substrate.

Background: Medicine involves not only prescriptions but also a well-developed emotional intelligence (EI). The assessment of EI of students at their entry to medical professional training may identify weaknesses, if any, so as to be taken care during the course. Thus, it may be relevant to explore it and its dimensions because it is still a nascent field of research, hence this study was planned.Methods: Objectives were to assess the EI and its dimensions of first year MBBS students. Study design was a descriptive and cross-sectional study. Study sample were 150 first year MBBS students. Ethical approval from institutional ethics committee and informed written consent from participants obtained; administered a questionnaire based EI test. Data obtained was analysed by ANOVA. Results: The 53.1 % participants were females and 46.9% males. The 73.1% were 17-18 years of age and 26.9% were 19-21 years old. The mean total EI score was 353.01. Among the emotional dimensions sensitivity was significantly low (p=0.047) in males (87.35±15.34) than females (92.49±9.071). The emotional competency was significantly low (p=0.055) in the elder group (153.59±26.99) than the younger one (160.61±15.762).Conclusions: The study identified certain gender and age differences in the EI and some weaknesses among first year medical students. Emotional sensitivity was significantly low in males and emotional competency was significantly low in the elder age group.

Metal nanoparticles especially of noble metals are used as an exogenous contrast agent for biomedical photoacoustic (PA) imaging in the tissue transmission window extending from visible to near infrared 700–1100 nm band. Different geometrical configurations of gold and silver nanoparticles like spherical core-shell, nanorod, and nanocages are promising candidates for thermoplasmonics, photothermal therapy, photothermal imaging, and photoacoustic imaging. In the current study, we simulated the photoacoustic response of gold and silica core-shell nanoparticle in water medium. Finite element simulations were carried out to study the spectral absorption response and effect of nanosecond laser pulse excitation on the spatial/temporal temperature as well as photoacoustic pressure variations of different core-shell geometry of nanoparticle. We have optimized the dimensions of gold nanosphere, gold-silica, and silica-gold core-shell geometries for optimum photoacoustic conversion efficiency. Further, the effect of shell thickness on the pulse photoacoustic signals for core-shell gold-silica and silica-gold nanoparticle has been studied. We concluded that silica-gold core-shell nanoparticles possess better photoacoustic conversion efficiency in comparison to gold nanosphere and gold-silica core-shell geometries. The prime aim of this study is to design efficient nano-probes for photoacoustic imaging, photoacoustic tomography, photothermal therapy, and drug delivery.

Two dimensional periodic arrays of microsquares of different dimensions are fabricated by direct ns-laser writing on silicon substrate. The micro/nano structures pattern on the Si surface significantly minimizes the optical reflection by light trapping effect, but enhances the SERS signal intensity of analyte dye molecule Rhodamine B (RhB) and Methylene Blue (MB) in presence of gold nanoparticles. The dependence of surface roughness, optical reflection and SERS intensity on the laser pulse energy and line scan interval is investigated. The SEM images clearly show well-ordered features on the surface of patterned Si substrates and aggregation of micro/nanoparticles on the substrate surface. The optical reflection from the patterned surfaces reduces below 11% over a broad range of wavelengths from 300 nm to 1200 nm. The patterned surface can be used as a reproducible SERS substrate with a spatially uniform enhancement factor of 10 8 . This fabrication method can be employed for preparation of multifunctional surfaces for light trapping in solar cells and for Raman signal amplification for versatile and reproducible SERS sensors.

We report the shape- and wavelength-dependent ultrasensitive label-free detection of adenine on rhodium cube- and tripod-star-like nanoparticles (Rh NPs) using ultraviolet surface-enhanced Raman scattering (UV-SERS). Rh NPs immobilized on a silane-treated glass substrate probed at near-resonant and non-resonant wavelengths served as the SERS platform for the highly reproducible, stable, and real-time detection of adsorbed adenine molecules in the femtomolar region. The sensitivity of SERS-active Rh NPs displaying LSPR in the UV region was exploited for the 266 nm (DUV), 325 nm (UV) and 532 nm (visible) Raman excitation wavelengths. With the 266 nm and 325 nm DUV-UV excitation lines, for the Rh tripod geometry near or pre-resonant excitation being closer to the analyte absorption band combined with the intrinsic UV-LSPR resonant energy produced a SERS enhancement factor as high as 105 and accelerated photoinduced degradations compared to 532 nm for our substrates. Computational results consistent with the experiment clearly demonstrated that the NP SERS enhancement was sensitive to both the intrinsic optical properties of Rh in the UV region and the excitation closer to the LSPR peak producing larger EM enhancements. The wavelength-dependent correlations between the optical properties of the shape-tailored Rh NPs and SERS enhancements envisage the merit and demerit of DUV-UV excitation over visible excitation for Raman measurements. The as-fabricated SERS substrate could also be efficiently recycled using O2 plasma for the detection of other biomolecules. The use of oxide-free transition metal Rh and DUV-UV excitation thereby extends the improved generality of the SERS technique for ultrasensitive bimolecular detection and for gaining a comprehensive understanding of UV-SERS-based applications.

Recently, 2D-layered nanostructures have aroused huge interest for environmental remediation applications. Nanostructured 2D-In2S3 nanosheets based advanced coating is fabricated by using the hydrothermal method. Uniform advanced coating of In2S3 nanosheets over fluorine-doped tinoxide (FTO) substrates with high adhesion properties were achieved at optimum reaction parameters. Microscopy studies results confirm the existence of assembly of two-dimensional sheets throughout the film. X-ray diffraction and Raman spectroscopy results manifest that 2D nanostructured thin film exhibits β-In2S3 phase. UV-DRS studies reveal that as-prepared In2S3 thin film is capable of adsorbing the entire electromagnetic spectrum from the UV to NIR region. The 2D-In2S3 nanosheets contained thin films have been employed for the breakdown of organic pollutant solutions such as methylene blue and methyl orange under natural sunlight. Fabricated 2D-In2S3 thin films show the unusually high photodegradation performance towards methylene blue (5 μM) oxytetracycline (0.3 mg/mL) and methyl orange (10 μM) solution and decomposed them in 20 min, 120 min, and 40 min, respectively. The improved photodegradation process due to broader optical absorption has been proposed and briefly elaborated The present work provides new insight into the field of advanced thin-film-based photocatalysis initiated by solar light.

Plasmonic semiconductor nanohybrids have generated the new advancement in the field of photocatalysis and SERS based sensing by their outstanding remediation and sensing capability towards the toxic organic pollutant that exists in the environment. We have synthesized Ag nanoparticles functionalized ZnO-CuO nanohybrids by the combined approach of hydrothermal and chemical reduction methods. TEM, FESEM, and elemental mapping results indicate the attachment of CuO nanoflowers with ZnO nanoflakes and also manifest the uniform attachment of Ag nanoparticles onto ZnO-CuO nanohybrids. X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray diffraction studies affirm the appearance of Ag@ZnO-CuO ternary nanohybrids. ZnO-CuO nanohybrids with uniformly attached Ag nanoparticles exhibit enhancement in the optical absorption spectra, while their PL studies indicate a significant decay in their PL intensity. Ag nanoparticles decorated ZnO-CuO nanohybrids decompose rhodamine (R6G) and oxytetracycline (OTC) molecules solution within 60 min under sunlight exposure. The improved lifetime of photogenerated charge carriers and the outstanding light-harvesting ability of Ag@ZnO-CuO nanohybrids effectively increase the photodegradation nature. Ag@ZnO-CuO ternary nanohybrids exhibit superior SERS-based efficient detection of rhodamine 6g (R6G) molecules. Enhanced photocatalytic activity and ultralow detection can be attributed to the effective charge transfer mechanism among Ag nanoparticles and ZnO-CuO nanohybrids. The present work explicitly reveals the contribution of Ag nanoparticles to the photodegradation nature and SERS-based detection of Ag@ZnO-CuO ternary plasmonic nanohybrids in a single platform.

To determine relationship between serum zinc levels and severity of diarrhea as determined by hydration status, duration of diarrhea and requirement for hospitalization. Also, to compare serum zinc levels in relation to rotavirus status. A prospective observational study which included 254 children aged 6 mo to 5 y with diarrhea was conducted. Serum zinc levels could be estimated in 198 children. Median (IQR) serum zinc levels of study population were 73.5 (59.11–92.86)μg/dl. Median (IQR) of serum zinc levels in children with dehydration and without dehydration were 69.64 (54.57–81.62) and 82.86 (64.1–103.48) μg/dl respectively (p

Laser ablation of Zn target in water, ammonium nitrate and cetyltrimethyl ammonium bromide (CTAB) was carried out to synthesize spherical, nanoflakes, nanosquares, nanoflowers and branched nanorods ZnO structures. Morphology of the ZnO nanostructures is controlled by varying ambient condition around laser generated plasma by means of either liquid temperature or addition of surfactant CTAB. In situ heating at temperature to 45, 65 and 85 C resulted in morphology variation from spherical to nanoflakes while ex situ heating at 65 C resulted in aggregation of spherical nanoparticles into nanosquares. Finally, simultaneous variation of CTAB and temperature (in situ and ex situ) generated nanoflakes, nanoflowers, nanosquares and branched nanorods. Highly anisotropic nano-flakes, nano-flowers, nano-squares and branched-nanorods structures display distinct optical absorption and emission behavior.

In the present work, we have investigated the functionalization of protein S-ovalbumin with laser-generated gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) using spectroscopic techniques. Biocompatible gold and silver nanoparticles were fabricated by nanosecond pulsed laser ablation (PLA) of metal target in water and directly conjugated to protein S-ovalbumin. The localized surface plasmon resonance (LSPR) of gold and silver nanoparticles is sensitive to particle size, shape, and surrounding medium refractive index. UV–visible absorption spectrum of both AuNPs and AgNPs showed red shift in LSPR after protein addition. The effect of laser fluence on the size of AuNPs and nanoparticle-protein conjugation in the size range 6–32 nm has been systematically studied. The presence of NPs resulted in broadening of S-ovalbumin absorption peak around 278 nm. Raman spectra of S-ovalbumin-NP assembly demonstrated breaking of disulfide bond and appearance of peak around 290 and 206 cm−1 corresponding to Au–S and Ag–S bond formation, respectively. Further, increase in the ratio of the 1350/1320-cm−1 doublet was observed, which indicates that hydrophobicity for tryptophan residues in the protein-NP assembly has increased. Fluorescence spectroscopy showed quenching in emission intensity of S-ovalbumin in the presence of AuNPs and AgNPs. The number of binding sites between AuNPs and S-ovalbumin has been found to be 1.4 with binding constant 4.5 × 109 M−1. The calculated values of binding constant and number of binding sites for AgNPs and S-ovalbumin were 2.4 × 109 M−1and 0.96, respectively.

Light collection efficiency and specific molecular detection are crucial factors for the performance of bio-chemical molecule sensors. In this paper, the low optical-reflection silicon (Si) substrates which combine reduced optical reflectivity by light trapping effect and high Raman enhancement ability of gold nanoparticles (Au-NPs) coated textured Si substrates are investigated for surface-enhanced Raman scattering (SERS). A fast, single-step and highly controllable nanosecond (ns) laser processing technique is employed to fabricate textured Si substrates under ambient conditions. Parallel arrays of micro-pyramids are fabricated on Si surface by direct laser writing two-dimensional structures. SEM micrographs clearly show well-ordered surface features in the form of micro-pyramid shape with well-defined sharp tips on the laser processed Si substrates. The aggregation of Si micro/nanoparticles on Si surface forms nanocavities and nanogaps and further enhances the surface roughness in order to minimize the optical reflection. The low optical reflection Si substrates exhibit optical reflection below 15% over a broad wavelength range from 300 nm to 1200 nm. The textured Si substrates with high signal reproducibility are successfully applied as SERS substrates to detect a very small concentration of Rhodamine B molecules with an average enhancement factor of the order of ~107. The low optical reflection and SERS signal amplification are also altered by the variation of laser pulse energy resulting into low optical reflection and high SERS signal intensity over the entire laser-patterned area. The effect of surface roughness on water contact angle was studied after the modification with Polydimethylsiloxane (PDMS), the surfaces show perfect superhydrophobicity with almost no water adhesion. This approach provides a novel high-speed and cost-effective method for fabricating SERS substrate with micro/nano-scale surfaces roughness and low optical reflection for high Raman signal enhancement.

We present fabrication of a low-cost surface enhanced Raman scattering (SERS) substrate. A composite graphene oxide (GO) decorated Ag nanodendrites (AgNDs) on the copper substrate has been prepared using a simple galvanic replacement of silver nitrate solution over copper foil and further spin coating it with GO. Graphene oxide serves as a protecting thin layer, avoiding the oxidation of AgNDs for highly sensitive and stable SERS applications. The sensitive SERS detection of Methylene blue (MB) is achieved as low as 10−7 M on rGO/AgNDs and 10−6 M on bare AgNDs.

Metal nanoparticles with highly branched morphologies are extremely advantageous owing to their unique structural properties and applications in sensing, imaging, and catalysis. In this work, anisotropically branched metal nanostructures are fabricated via a simple and one-step chemical reduction method. The fabricated nanostructures display highly branched dendritic morphology and exhibit a broad plasmonic response from UV to NIR region of the electromagnetic (EM) spectrum. The fabricated silver nanostructures were utilized for the Surface Enhanced Raman Spectroscopy (SERS) based detection of Rhodamine B dye molecules with a Raman intensity enhancement factor of the order of ∼109. The extreme localization of EM fields at the sharp tips and within the nanoscale inter-branch gaps results in an ultralow limit of detection ∼10−18 M concentration of the analyte with high signal reproducibility. The present methodology provides a reliable method for the preparation of silver nanodendrites based SERS substrates and offers great potential for the ultrasensitive detection of analyte molecules.

Semiconductor based photocatalysis has been proven a benchmark in the field of environmental remediation and water detoxification. We report the synthesis of ZnO nanoflakes (ZNF) and their subsequent transformation in ZnO nanosheets (ZNS). ZNF was prepared by wet chemical method while the hydrothermal method was used for the synthesis of ZNS. The morphological variations have been confirmed through the scanning electron microscopy (SEM). The SEM results reveal the presence of nanoflakes with an average length of 187 nm. The measured average length and width of ZNS are found to be 350 nm and 120 nm respectively. Optical absorption studies reveal enhancement of absorption of ZNS as compared to ZNF. The optical band gap value of ZNF and ZNS was obtained from Tauc plot method. The estimated bandgap for ZNF and ZNS are found to be 2.7, and 3.1 eV, respectively. The crystallographic properties of ZnO samples have been studied by X-ray diffraction (XRD). ZnO samples have been employed for the decomposition of methylene blue (MB) dye under sunlight exposure. The photocatalytic studies reveal that ZNS exhibits enhanced photocatalytic activities for degradation of MB dyes solution as compared ZNF. ZNS sample decomposed the 10µM MB dye solution in just 15 min. The superior photodegradation activity of ZNS is ascribed to the high surface area and improved sunlight utilization capability.

Gold nanospheres and nanorods are promising agents for photoacoustic imaging and photothermal therapy. In this work, seed-mediated methods were optimized for the synthesis of gold nanosphere and nanorod collides of different sizes. Nanosecond pulse photoacoustic and photothermal analysis of these nanoparticles was carried out and compared with finite element simulation. The simulations were performed to quantify the size dependent photoacoustic signal enhancement for nanospheres and nanorods. The non-sphericity contribution of nanospheres was found to enhance the photoacoustic signal. Nanosecond pulse photoacoustic studies of nanorods of different aspect ratio were carried out. Nanorods of aspect ratio ∼4.8 were found to be the most efficient photoacoustic signal generators. Photoacoustic studies of nanorods at varying laser fluence were performed and threshold fluence of 5 mJ cm-2 was observed. Nanorods exposed to nanosecond laser pulses underwent size and shape variations which were confirmed by optical absorbance and transmission electron microscopy measurements. Simulations of nanorods of different aspect ratio and diameter were performed to investigate the photoacoustic signal enhancement and photothermal stability. The miniature size nanorod with a diameter of 10 nm and aspect ratio of 5 was found to be most appropriate in terms of photoacoustic signal generation and photothermal stability.

Metal nanostructures with highly branched morphologies are attractive due to their fascinating plasmonic properties which are related to their unique morphological features. In this work a simple fabrication methodology is used for fabrication of surface-enhanced Raman spectroscopy (SERS) substrates composed of branched silver nanostructures with dendritic morphology. The high Raman intensity enhancement factor of the order ∼1010 was achieved which allows the detection of ∼zeptomole thiram molecules by SERS substrates. The appearance of new bands at 344 cm-1 and 1521 cm-1 provides an evidence of contribution of chemical enhancement in SERS. The observed spectral changes in SERS spectrum originate from the adsorption of the analyte on the metal surface and provide an insight into molecule-metal interaction in SERS. The extreme sensitivity of SERS substrates is discussed in terms of the distinction between electromagnetic and chemical enhancement mechanisms. Moreover, the highly sensitive SERS substrates were used for simultaneous detection of Rhodamine B and thiram molecules from their mixture with different individual concentrations demonstrating detection capabilities for the identification of pesticides with dye molecules.

Herein, shape-tailored indium nanotriangles and nanowires were synthesized via a modified polyol reduction method. These nanoparticles exhibit local surface plasmon resonance in UV regions, near 345 nm for nanowires and 336 nm for nanotriangles. In this study, we report surface enhanced Raman scattering (SERS) and detection of tryptophan molecules using indium (In0) as the enhancing plasmonic nanostructure under non-resonant conditions. Under 632.8 nm excitation, Raman line at 1612 cm−1 for the tryptophan molecules (10−7 M) deposited on the self-assembled indium nanoparticle substrates show intensity enhancement factor (EF) of ∼104 and ∼103 for the triangular and nanowire morphology, respectively. The experimental results are in good agreement with the finite-difference time domain (FDTD) simulations of electric field contours, exhibiting manifold enhancement of the electromagnetic field localized at the tips and corners of the indium nanostructures, generating hot spots. The synthesis and analysis of the shape-dependent SERS activity of the anisotropic indium nanoparticles can be utilized for the design of versatile SERS substrates as a promising alternate exogenous contrast agent for enhanced Raman scattering from biomolecules.

We report an ultrasonic sensor based on open-cell photoacoustic spectroscopy method for the detection of explosive agents in traces. Experimentally, we recorded photoacoustic spectra of traces of hazardous explosives and molecules. Tunable mid-infrared quantum cascade lasers in the wavelength range 7.0–8.8 µm lying in the molecular fingerprint region are used as optical source. Samples of Pentaerylthirol Tetranitrate (PETN), Tetranitro-triazacyclohexane (RDX), Dinitrotoluene, p-Nitrobenzoic acid and other chemicals like Ibuprofen having quantity ~1.0 mg were detected using a custom made photoacoustic cells in both open and closed configurations. The explosive traces were swiped using paper from contaminated surface and detected. Finite element mesh based simulation of photoacoustic cell is carried out for optimization of geometry at ultrasonic frequency (40 kHz). A point sensor based on above approach will be very effective for forensic applications and suspicious material screening.

Anisotropic growth of Pd nanoparticles in bromine (Br) containing solution has been studied by pulsed laser ablation. For size and shape control different solutions like water, sodium dodecyl sulphate (SDS) (anionic surfactant), and (Br−) ion containing cetyltrimethylammonium bromide (CTAB) (cationic surfactant) and electrolyte (KBr) were used. In laser ablation surrounding liquid plays a dominant role in controlling size and directional growth. Absorption spectra of as-generated Pd nanoparticles undergo modification with time in different solutions due to Br− ion-mediated directional growth. In water and SDS quasi-spherical and spherical Pd nanoparticles with mean size of 14 and 8 nm, respectively, and in CTAB decahedron and icosahedron shape Pd nanocrystals with mean size 65 nm were observed. When strong Br− ion source KBr was used sharp edged cuboid shaped large Pd nanoparticles were observed. Surface energy modification due to preferential chemisorption of Br− ions onto {100} planes of Pd resulted in formation anisotropic Pd nanostructures enclosed with {100} planes. The nanocubes exhibit broad plasmon resonance around 250–280 nm. Further, size of nanocuboids were controlled by using mixed solutions of KBr with SDS and CTAB for tunable plasmon resonance wavelength from 230 to 550 nm.

We demonstrate a standoff system based on quartz-enhanced photoacoustic spectroscopy technique for the concentration measurements of atmospheric ozone and methane. The technique is a modified version of Photoacoustic spectroscopy. Two primary features of this technique are the employment of a tunable quantum cascade laser and a resonant quartz-crystal tuning fork detector. Both of these features facilitate simultaneous sensing of multiple molecular species. External-cavity quantum cascade laser having a spectral range from 7 to 10 micron is used. Diurnal concentration variations of methane and ozone are estimated for open-path up to 25 m. The ambient methane and ozone concentration maxima were observed to have values of 3.5 parts per million by volume and 140 parts per billion by volume, respectively. Finite-element mesh-based software is used to simulate the Eigen frequency of the tuning fork sensor. High-resolution transmission molecular spectroscopic database of atmospheric gases and the real-t...

Nanostructured two-dimensional transition metal dichalcogenides (2D-TMDCs) have been attracting great attention in the field of environmental remediation and sensing due to their high surface area and layer dependent optical and structural properties. Surface area dependent performance of MoS2 nanostructures is one of the important aspects which need to be explored for various environmental applications. In this work, MoS2 nanoflowers with tunable surface area (5–20 m2/g) were prepared by the facile hydrothermal method and their surface area dependent SERS and photodegradation activity were explored. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) studies assure the growth of MoS2 nanoflowers by the assembly of 2D-MoS2 nanosheets. MoS2 nanoflowers exhibit excellent sunlight-induced photocatalytic activity towards the degradation of methylene blue, methyl orange, rhodamine 6G and oxytetracycline hydrochloride molecules. We report that a very low amount (0.025 mg) of MoS2 nanoflowers (20 m2/g) can tremendously decompose 10 μM of MB, MO and R6G dye molecules in just 12 min, 30 min and 45 min respectively and 0.5 mg/10 mL OTC-HCl molecule in 60 min under sunlight which has not been reported yet. MoS2 nanoflowers based substrates show the remarkable SERS based detection towards the rhodamine B (RhB) molecule. Tunability in the SERS for the account of different surface areas poses by the different MoS2 sample has been well explored. Charge transfer mechanism for ultrafast SERS detection and enhanced photodegradation activity has been proposed and explained precisely.

Two-dimensional (2D) semiconductor nanostructures have gained tremendous interest in the field of environmental remediation and water purification. Nanostructures coated surfaces provide new insight for the development of cost-effective advanced photocatalyst. In this study, 2D-MoS2 nanosheets based coating has been developed through the combined effort of the exfoliation and a spin coating method. Microscopy analysis inferred the formation of nanosheets from the bulk structured MoS2 with the reduction in their average dimensions. Exfoliated MoS2 nanosheets formed in 18 h reaction time has average length ~1019 nm and width~544 nm. Cross-sectional SEM studies confirm the formation of MoS2-PVA thin films with different orientation of MoS2 nanosheets. UV–Vis absorption spectroscopy studies exhibit two peaks at 619 nm and 680 nm with improved optical absorption. The XRD and Raman spectroscopy analysis reveals the 2H-phase of MoS2 nanosheets. 2D-MoS2-PVA composite thin film was tested as an advanced photocatalyst coating for the breakdown of methylene blue (MB) and malachite green (MG) pollutant molecules under sunlight. 2D-MoS2-PVA composite thin film decomposed the 5 μM solution of MB and MG molecule solutions in 80 min and 40 min, respectively, under sunlight (800 W/cm2). The efficient photodegradation performance of the 2D-MoS2-PVA composite indicates their potential usage in other environmental applications.

Cubic structured CuO thin films were fabricated through a combined effort of electrochemical and thermal annealing processes, and their solar light-induced photodegradation and non-enzymatic sensing behavior were well studied. Nanocubes like structures were achieved by varying the time during the electrochemical deposition. Raman spectroscopy and X-ray diffraction studies reveal the monoclinic phase of CuO thin films while scanning electron microscopy highlights the modulation in the size and density of cube-like morphology of CuO thin films. Atomic force microscopy also assures the existence of cube-like nanostructures. Modulation in the optical behavior of CuO thin films was explored by the UV–visible spectroscopy, which indicates the bandgap narrowing in CuO thin films with the deposition time. Sunlight driven photodegradation performance of CuO thin films was explored by decomposition of Methylene Blue molecules. CuO thin films with different nanocubes density exhibit outstanding sunlight-induced photodegradation activity by degrading 5 µM MB dye solution in 90 min. Cubic nanostructured CuO thin film also reveals the outstanding non-enzymatic glucose sensing behavior with a high sensitivity of 1311.83 μA mM−1 cm−2, the wide linear range of 0.001–1.8 mM, fast response times (less than 5) and low detection limit (LOD) of 0.068 µM under a signal/noise ratio of 3.

Colored TiO2 has tremendously attained significant interest worldwide due to its fascinating optical properties. Mesoporous dark brown TiO2 nanospheres with extremely high surface area (1246 m2/g) fabricated through the combined approach of thermal annealing with the sol–gel method. FESEM images inferred the creation of the spherical structure of 357 nm which transformed into defected mesoporous TiO2 spheres of 452 nm under annealing at 350 °C. UV-DRS PL and EPR studies confirm the bandgap narrowing due to the creation of oxygen defects sates in the TiO2 sample. Dark brown TiO2 exhibits remarkable sunlight-induced photodegradation activity for methylene blue and oxytetracycline hydrochloride molecules. Mesoporous TiO2 defect rich spheres adsorb the 32% of the MB pollutant molecules in just 30 min. Moreover, it decomposes the rest 67% of 15 µM MB dye solution and 0.5 mg/mL OTC solution in 30 min and 80 min respectively. Existences of high oxygen defect states in TiO2 were responsible for the bandgap narrowing and improve charge carriers separation and superior photocatalytic activity (PCA). Mesoporous dark brown TiO2 sample was also investigated for the energy storage application. Unusual high surface area also facilitated the accumulation of charges and led to the enhancement in charge storage properties.

Semiconductor nanohybrids garner huge interest among environmentalists for the various applications owing to their efficiency, cost-effectiveness and benignity. We report the fabrication of TiO2 nanoparticles (TNPs) functionalized ZnO nanoflakes (ZNFs) and their outstanding detoxification ability towards the methylene blue (MB), rhodamine 6G (R6G) and Oxytetracycline (OTC) molecules solution in water. TEM studies confirm the formation of 3D architecture of ZnO–TiO2 nanohybrids while high-resolution transmission electron microscopy assures the uniform functionalization of TNPs over ZNFs. Scanning electron microscopy studies reveal the modulation in the surface morphology with the tenability in volume ratios of Zn and Ti sources. Significant PL quenching in ZnO–TiO2 nanohybrids spectrum as compared to ZNFs confirms the improvement in the charge separation which is highly favorable for the enhancement in the photodegradation efficiency. The 3D architecture of ZnO–TiO2 with volume ratio (Zn: Ti: 4:1) showed superior photodegradation activity and decompose OTC, MB and R6G dye solution within 8 min, 6 min and 30 min respectively under natural solar light (~862 W/cm2). Most efficient ZnO–TiO2 nanohybrid exhibits extremely high rate constant values for MB, R6G and OTC molecules which are 7, 5 and 4.8 times of the rate constant value of pure ZNFs. Extremely superior photodegradation performance of 3D architecture of ZnO–TiO2 nanohybrid could be ascribed to the charge separation and synergistic effect between the TNPs and ZNFs which is responsible for the high density of electrons in the conduction band of ZnO–TiO2 nanohybrids. ZnO–TiO2 nanohybrids reveal the extremely high photodegradation rate for the decomposition of azo dyes and pharmaceutical residue which has not been reported till now.

We report synthesis and application of a unique heterojunction nanocomposite formed between copper nanoparticles (CNPs) and defect rich ZnO nanoflakes for application towards water remediation. Systemic variation in CNPs functionalization was seen to modulate the optical, structural and photocatalytic properties of the heterojunction, which were found to be well in accordance with the results from TEM, UV-DRS and EPR. The remediation ability of the heterojunction measured in terms of its photocatalytic ability was studied by degrading three different organic dye pollutants Rhodamine 6G (R6G), Methylene Blue (MB) and Methyl Orange (MO) using solar light (850 W/cm2) as the renewable excitation source. CNPs loading density was seen to follow a direct linear relationship to optical absorbance and band gap narrowing. The initial increase in photolytic efficiency is associated with improved visible light response and reduced band gap due to attachment of CNPs while reduction in activity was found to be associated with generation of self-recombination centres in CuO functionalization. Optimized CNP modified ZnO nanoflakes was able to decompose 10 µM of R6G, MB and MO dye solutions in 80, 40 and 60 min respectively.

Hybrid nanoparticles (HNs) play a very important role in nanoscience and nanotechnology and therefore have become a topic of intense research in recent years. This is due to the special physical and chemical properties of these materials that open new avenues in advanced applications. In the field of catalytic applications bi- and trimetallic HNs are more highly efficient than monometal nanoparticles (NPs). Having so many advantages, there is still no general method for reliable synthesis of multimetallic core–shell or alloy HNs. There is a strong need for the development of new HNs based on plasmonic materials, aluminum (Al), silver (Ag), and gold (Au), that enables the physical trapping of a wide variety of analyte molecules, and therefore combining these three elements we can have wide tunability of LSPR from UV to IR range and hence wide applications. In this chapter a very effective and a versatile one-step method to fabricate multicomponent HNs of various types: Ag–Al rattle-type HNs with hollow cavities, bimetallic (Al2O3@Ag, Al2O3@Au), and trimetallic Al2O3@AgAu HNs using PLAL and post laser heating is presented. This new mechanism of PLAL technique opens new opportunities to develop a large variety of novel hybrid materials with controllable morphology and hence properties.

Surface enhanced IR absorption (SEIRA) and Surface enhanced Raman scattering (SERS) of amino acids in protein (L-Tryptophan) drop coated on deposited silver nanoislands over monolayer of graphene on silicon were obtained using FTIR in reflectance mode and micro-Raman respectively. In this work, two dimensional Ag nanoislands were prepared on LPCVD-grown monolayer graphene on Si. Here we describe the enhanced interaction between light and silver nanoislands deposited on graphene as a tool for trace detection of molecular entities, especially in the area of bio-molecule detection and characterisation. This enhanced interaction is due to localised surface plasmons generated in silver nano islands that we fabricate by simple means of metal deposition on top of graphene. We have achieved femto molar detection limit of L-Tryptophan on monolayer graphene.