Microwave-assisted synthesis and upconversion luminescence of NaYF4:Yb, Gd, Er and NaYF4:Yb, Gd, Tm nanorods.

Anisotropic rare earth ion (RE3+) doped fluoride upconversion particles are emerging as potential candidate in diverse areas, ranging from biomedical imaging to photonics. Here, we develop a facile strategy to synthesize NaYF4: Yb, Gd, Er, and NaYF4: Yb, Gd, Tm upconversion nanorods via microwave synthesis route by controlling the synthesis time and compared the optical properties similar nanorods prepared via solvothermal technique. With the increase in synthesis time, the phase of the particle found to change from mixed phase to purely hexagonal and morphology of the particles change mixed phase of spherical and rod-shaped particles to completely nanorods for a synthesis time of 60 min. Further, the intrinsically hydrophobic particles changed to hydrophilic by removal of oleic capping via acid treatment and the amine functionalized silica coating. The upconversion luminescence as well as laser power dependent emission properties of the surface modified particles elucidate that surface modification route influence the upconversion luminescence as well as solvent dependent emission properties. Moreover, the laser power dependent studies elucidate that the upconversion process in a multi-photon process.

Subcellular Imaging and Diagnosis of Cancer using Engineered Nanoparticles.

The advances in the synthesis of nanoparticles with engineered properties are reported to have profound applications in oncological disease detection via optical and multimodal imaging and therapy. Among the various nanoparticle-assisted imaging techniques, engineered fluorescent nanoparticles show great promise from high contrast images and localized therapeutic applications. Of all the fluorescent nanoparticles available, the gold nanoparticles, carbon dots, and upconversion nanoparticles are emerging recently as the most promising candidates for diagnosis, treatment, and cancer monitoring. This review addresses the recent progress in engineering the properties of these emerging nanoparticles and their application for cancer diagnosis and therapy. In addition, the potential of these particles for subcellular imaging is also reviewed here.

Nanoparticle impregnated self-supporting protein gel for enhanced reduction in oxidative stress: A molecular dynamics insight for lactoferrin-polyphenol interaction.

In the present work, lactoferrin (Lf) based nanoparticle incorporated self-supporting gel encapsulating a flavonoid, quercetin (Q), was developed. The complex formation between Lf and Q was assessed using molecular docking and dynamics simulation that lactoferrin and quercetin showed strong interaction and binding supporting hydrophobic interaction. The microscopic, spectroscopic, and x-ray techniques were used to characterize the gel extensively. In vitro drug release was studied to understand the release pattern of quercetin from the protein gel. The viscosity of the gel and its rheological characteristics were determined using a Brookfield viscometer. Ex vivo skin permeation studies using vertical diffusion cells were carried out to understand its skin permeation properties. The gel showed strong anti-oxidant activity using the DPPH scavenging assay. The enhanced effect of the Lf-Q complex on antioxidant enzyme activity (superoxide dismutase, catalase, and malondialdehyde), was supported by molecular dynamics, surface hydrophobicity, and in vitro studies. To investigate the effect of the gel on angiogenesis, the chorioallantoic membrane assay was performed and its compatibility with erythrocytes was also assessed. Suitability for topical administration was assessed using skin irritation studies performed on Sprague Dawley rats. The overall results suggest that the developed NiPG is suitable for cutaneous localization of quercetin with enhanced antioxidant activity.

ZIF-8 nano confined protein-titanocene complex core-shell MOFs for efficient therapy of Neuroblastoma: Optimization, molecular dynamics and toxicity studies.

In the present study, we have developed the core-shell metal organic framework (MOF) of zinc, wherein titanocene dichloride (TC) loaded lactoferrin (Lf) functioned as a core. The complexation of TC to Lf was studies using molecular dynamics study, Quantum mechanical model and spectroscopic investigations. Plackett-Burman design was used to screen and select the critical factors affecting the responses (size, zeta potential and PDI) while the effect of those parameter on the quality attributes (size and yield) was studied by means of a Box-Behnken design. The optimised Lf-TC nanoparticles were loaded inside the ZIF-8 framework along with an anticancer agent 5 Fluorouracil and characterized using techniques like FTIR, PXRD, Raman spectroscopy, EDX and UV-NIR spectroscopy and morphological techniques like SEM, TEM, AFM. The compatibility of the loaded ZIF-8 framework was examined by haemocompatibility studies. The potential of developed nanoplatform against Neuroblastoma was assessed using a cell line studies along with in vivo toxicity studies to ascertain its safety for after in-vivo administration in Wistar rats. Therefore, we can conclude that by employing the approach of DOE we were able to optimize the size and yield of Lf-TC NPs and further by loading inside ZIF-8 framework along with an anticancer drug like 5 fluorouracil we were able to develop a potential nanoplatform for the multimodal therapy of Neuroblastoma.

Hyaluronic acid-drug conjugate modified core-shell MOFs as pH responsive nanoplatform for multimodal therapy of glioblastoma.

Multimodal therapeutic approach has been gaining lot of attention for effective therapy of cancer. In the present work, a novel and unique pH responsive nanoplatform have been developed for multimodal therapy of glioblastoma using protein, biopolymer and MOFs. Lactoferrin (Lf) has been used as protein matrix for loading titanocene which was then enclosed in ZIF-8 framework along with 5-FU (ZIF-8@Lf-TC). The ZIF-8 was further coated with Lenalidomide-HA conjugate linked via hydrazone linkage (LND-HA@ZIF-8@Lf-TC). The developed nanocomposite was extensively characterized using spectroscopic, x-ray and electron microscopic techniques. The nanocomposites were evaluated for pH responsive drug release, stability, bio-interaction, and haemocompatibility which confirmed pH responsive nature of nanocomposite, stability and absence of any significant interaction with biomolecules. In obtained results for in vitro cell line studies performed in U87MG and RAW264.7 cells demonstrated enhanced cell cytotoxicity against cancer cells which was further supported by results of cellular ROS generation and surface ROS generation by nanocomposites. The Zinc and Lf mediated disruption of intracellular IL-6 and TNFα levels was observed with synthesized nanocomposites. They demonstrated pH responsive release of 5-FU and LND along with sustained release of both drugs in simulated medium. The LND-HA@ZIF-8@Lf-TC demonstrated superior cell growth supressing ability compared to ZIF-8@Lf-TC and ZIF-8. The nanocomposites were stable in biomimicking environment as well as did not show any significant interaction with RBC, plasma or CSF. The overall results suggest that LND-HA@ZIF-8@Lf-TC can be explored as promising platform for dual drug delivery mediated multimodal therapy of cancer.

Post annealing induced manipulation of phase and upconversion luminescence of Cr3+ doped NaYF4:Yb,Er crystals.

The role of post synthesis annealing at different temperatures (200-600 °C) on the structural as well as luminescence properties of NaY80%F4:Yb17%,Er3% prepared via a coprecipitation method was found to change the structure from a cubic to hexagonal phase with a concomitant increase in upconversion luminescence by 12 times for the green region and 17 times for the red region. Addition of the Cr3+ ions (5-20 mol%) into the host followed by post annealing at 200-600 °C causes that the samples to exhibit phase dependent and upconversion luminescence behavior that depend upon the doping concentration as well as the annealing temperature. The inductively coupled optical emission spectroscopy reveals that only 1/600 times of the desired volume of the co-dopant goes to the lattice and it can manifest visible spectral changes in the diffuse reflectance spectra of the samples. The samples co-doped with Cr3+ ion concentrations of 10-15% and post-annealed at 600 °C were found to have maximum emission with an enhancement factor of 24 for the green region and 33 for the red region. In addition, the laser power dependent studies reveal that even for the power density levels 3.69 W cm-2 to 32.14 W cm-2, the samples are in the saturation regime and most of the samples investigated here follow a single photon process, and a few samples show a slope value less than 1 for laser power dependent intensity plots. The results show the remarkable promise of controlled tailoring of the properties of upconversion crystals via post annealing and co-doping.