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Chondrosarcomas are the second most common primary malignant bone tumors. Head and neck chondrosarcomas constitute less than 10% of these tumors, rarely arising from the nasal septum. These are locally aggressive malignant tumors arising from the cartilaginous framework of the nasal septum. Rarity of the tumor coupled with nonspecific symptoms makes it a diagnostic dilemma. Diagnosis requires endoscopy, radiology, and final histopathology for confirmation. Treatment is mainly surgical, requiring complete surgical excision with clear margins. Radiation has a role in unresectable tumors or for tumors with positive margins after surgery. Survival depends on the grade of tumor that predicts the metastatic potential of the tumor. We present a rare case of chondrosarcoma arising from the nasal septum in a 29-year-old young female presenting with complaints of nasal obstruction. Computed tomography was suggestive of a calcified cartilaginous tumor arising from the nasal septum. Endoscopic excision was done and postoperative histopathology showed grade II chondrosarcoma with clear margins. No adjuvant treatment was given to our patient and 2 years post-excision patient is disease free.To conclude, chondrosarcoma of the nasal septum is a rare tumor, with nonspecific symptoms. Surgery with clear margins remains the treatment of choice. Prognosis depends on the extent of tumor at presentation, resection margins, and grade of tumor.

In the present work Cadmium Selenide (CdSe) and Eu-doped CdSe nanostructures were synthesized by using hydrothermal route. The average crystallite size revealed by powder X-ray studies was found to increase for Eu-doped nanostructures. Morphology study of the Eu-doped CdSe was performed on FESEM and HRTEM. SAED pattern unveiled the crystalline nature of CdSe nanoparticles. UV–Vis absorption studies for the optical band gap was found to be 1.83 eV for CdSe nanoparticles and for Eu3+-doped CdSe it was 1.81 and 1.79 eV, respectively. XPS spectra revealed the presence of prominent cadmium, selenium, and europium peaks for different energy bands. Temperature- and frequency-dependent dielectric studies were performed for the nanostructures. It was observed that ac conductivity increases with the increase in temperature.

Cadmium Selenide (CdSe) quantum dots (QDs) semiconductors having direct band gap exists in different colours which depends on the size of the particles. Doping can be easy in semiconductors but adding impurities in quantum range was always considered as challenging. In the present work, we have carried out studies on the doping of CdSe QDs with Samarium 3+ (Sm3+) impurities. Four different sizes of particles were synthesised by kinetic growth route using 3-mercaptopropionic acid (3-MPA) as the capping agent. The prepared samples were characterized by ultra violet-visible (UV) and photoluminescence (PL) for their optical properties and fourier transform infrared spectroscopy (FTIR) for vibrational studies. The evidence of doping was traced by the results from the optical properties A blue shift in the absorbance spectra was recorded when compared with undoped CdSe QDs. This shift was attributed due to the transfer of energy from the host material to the dopant. The broadband PL spectra covering the entire visible range were recorded for undoped and doped QDs. In undoped CdSe QDs only band edge emission was noticeable, but after incorporating Sm3+ dopant defects were generated in QDs. Sm3+-doped CdSe QDs showed emission spectra including band edge and defect driven emissions.

In this work, silver nanoparticles (Ag NPs) were deposited on a heated glass substrate by using thermal evaporation technique without any additional annealing process. Ag NPs show stronger plasmonic increment of photoluminescence in comparison with other noble metals. The characterization techniques such as SEM, XRD, and UV-Vis. were used to analyse optical and morphological studies of these deposited metal NPs. Growth of nanospheres in Ag thin films were revealed by SEM. The substrate temperatures were varied from 150 °C, 250°C to 350 °C. Under some conditions, the Ag NPs exhibit a broad absorption in visible region. This is attributed to their LSPR effect i.e. Localized Surface Plasmon Resonance effect. Here, substrate temperature is the key parameter for controlling Ag NPs size and shapes.

Silver(Ag) metal has been known for its excellent anti-microbial activities. With the interaction of these metal nanoparticles with human cells, a hint of safety emerges. In this present work we have synthesised a composites of Ag with Cadmium Selenide (CdSe) Quantum Dots (QDs) for their cytotoxicity measurements. Due to the high luminescent properties of CdSe QDs these nanostructures can be used in medical detection and treatments. Morphological studies of CdSe QDs and Ag composites with CdSe were done using TEM. It was seen from the TEM image that, Ag formed a coating layer over QDs. Cytotoxicity of CdSe based QDs were measured onHuman embryonic kidney(HEK293) cell line using MTT assay. It was found from the measurements that QDs were non-toxic even at higher concentration on 1000nM for 24 hours. When toxicity levels of both the samples were compared it was found that the composites of Ag with CdSe were non-toxic than CdSe QDs. The morphology of HEK293 cell line was continuous evaluated using an optical microscope. With these advantages of less toxicity the composites of CdSe QDs with Ag can be used in vitro biological imaging technique and other various medical detection and treatments.

Optical sensors based on quantum dots have been a promising alternate for the organic dyes or fluorophores for detection label which have applications in biological sensing. The present work examines a technique that utilizes hybrid nanostructures for the detection of glucose and behaves as an optical sensor. This technique has exemplified the detection of glucose under various oxidases and enables the hybrid Au–CdSe nanostructures as sensor. The method demonstrates the effect of hydrogen peroxide (H2O2) on the fluorescence intensity of Au–CdSe QDs by modifying H2O2 concentration. The prepared samples were then characterized by high-resolution transmission electron microscopy for its structural morphology of the nanoparticles and their hybrids and photoluminescence (PL) spectroscopy for their optical properties. Because of the presence of Au NPs in the samples, initially there was an enhancement in the PL intensity by adding few micro-liters of H2O2 resulting in 70 mM and up to 130 mM concentration of H2O2, after which it suddenly showed a dramatic decrease in the PL intensity with increase in the concentration of H2O2 beyond 130 mM in the hybrid Au–CdSe nanostructures due to the inner field effect. The quenching percentage when calculated was found to be 80%. In comparison to the other available techniques the presented method is very simple, reproducible with effective sensitivity for sensing glucose and is quiet economical too.

Increased usage of gold nanoparticles (Au NPs) in the high-tech world made these one of the pivotal components for large number of applications. In the present work, we present the fabrication of Au NPs and their characterisation for shape, size distribution and surface plasmon (SP) studies. Au NPs were synthesised on Si substrate in a self-assembled manner with different densities. In situ substrate heating was done to fabricate Au NPs with minimum size variation and direct deposition of these on the Si substrate. The prepared samples were then characterised by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), high-resolution transmission electron microscope (HRTEM), photoluminescence (PL) and UV-Vis diffuse reflectance spectroscopy (UV-DRS). The average size of the nanoparticles from FESEM was found to be 3, 5 and 9 nm for substrate temperatures of 400, 500 and 600 °C, respectively. Due to the high density of deposited Au NPs on the substrate, a strong and broad surface plasmon band was observed. UV spectra showed a shift in the absorption maxima towards the red region with increase in the temperature of substrate.

Semiconductor nanophosphors have the exceptional resources to demonstrate the quantum phenomenon due to their tailored-size dependent photoluminescence (PL). The work here is focused on the synthesis of highly luminescent Cadmium Selenide (CdSe) Quantum Dots (QDs) by a simple technique. This is a time dependent process where change in the size of CdSe QDs was observed at a reaction temperature of 100 °C without any inert atmosphere. The CdSe QDs were synthesised by using 3-Mercapto propionic acid (MPA) rather than using the typically utilized capping agent. All the samples were characterised for their optical properties. The size of QDs was calculated in a range up to 3 nm by UV–Vis Spectroscopy and confirmed by High Resolution Transmission Electron Microscopy (HRTEM). It was clear from the UV studies that QDs exhibit size dependent tunable optical absorption. The broad Photoluminescence (PL) emission spectra depicts the presence of surface defects produced along with band edge spectrum. The absorbance and emission spectra were shifted to the red region due to the quantum confinement effect occurred in QDs. The water soluble QDs were economical and easy to fabricate has applications in Light Emitting Diodes (LEDs).