Synthesis and evaluation of curcumin reduced and capped gold nanoparticles as a green diagnostic probe with therapeutic potential.

Curcumin, a compound in turmeric, shows promise for its anti-cancer properties. In this study, we successfully synthesised curcumin-reduced and capped gold nanoparticles. Most evaluations have been limited to in-vitro studies for these nanoparticles; our study takes a step further by highlighting the in-vivo assessment of these curcumin-reduced and capped gold nanoparticles (GNPCs) using non-invasive imaging (SPECT and optical) and possible therapeutic potential. The GNPCs showed an average hydrodynamic diameter of 58 nm and a PDI of 0.336. The synthesised and fully characterised GNPCs showed ex-vivo hemolysis value of ≤ 1.74 % and serum stability of ≥ 95 % over 24 h. Using in-vivo non-invasive (SPECT and optical Imaging), prolonged circulation and enhanced bioavailability of GNPCs were seen. The biodistribution studies after radiolabelling GNPCs with 99 mTc complemented the optical imaging. The SPECT images showed higher uptake of the GNPCs at the tumour site, viz the contralateral muscle and the native Curcumin, resulting in a high target-to-non-target ratio that differentiated the tumour sufficiently and enhanced the diagnostics. Other organs also accumulate radiolabeled GNPCs in systemic circulation; bio dosimetry is performed. It was found that the dose received by the different organs was safe for use, and the in-vivo toxicity studies in rats indicated negligible toxicity over 30 days. The tumour growth was also reduced in mice models treated with GNPCs compared to the control. These significant findings demonstrate that GNPC shows synergistic activity in vivo, indicating its ability as a green diagnostic probe that has the potential for therapy.

Synthesis of highly luminescent core-shell nanoprobes in a single pot for ofloxacin detection in blood serum and water.

Antibiotics are commonly used as antibacterial medications due to their extensive and potent therapeutic properties. However, the overconsumption of these chemicals leads to their accumulation in the human body via the food chain, amplifying drug resistance and compromising immunity, thus presenting a significant hazard to human health. Antibiotics are classified as organic pollutants. Therefore, it is crucial to conduct research on precise methodologies for detecting antibiotics in many substances, including food, pharmaceutical waste, and biological samples like serum and urine. The methodology described in this research paper introduces an innovative technique for producing nanoparticles using silica as the shell material, iron oxide as the core material, and carbon as the shell dopant. By integrating a carbon-doped silica shell, this substance acquires exceptional fluorescence characteristics and a substantial quantum yield value of 80%. By capitalising on this characteristic of the substance, we have effectively constructed a fluorescent sensor that enables accurate ofloxacin analysis, with a detection limit of 1.3 × 10-6 M and a linear range of concentrations from 0 to 120 × 10-6 M. We also evaluated the potential of CSIONPs for OLF detection in blood serum and tap water analysis. The obtained relative standard deviation values were below 3.5%. The percentage of ofloxacin recovery from blood serum ranged from 95.52% to 103.28%, and from 89.9% to 96.0% from tap water.

High quantum yield carbon dots and nitrogen-doped carbon dots as fluorescent probes for spectroscopic dopamine detection in human serum.

Recent advances in fluorescent carbon dots have shown great potential for the sensing of biological molecules. In this study, one-step hydrothermally synthesised carbon dots (CD) and nitrogen doped carbon dots (NCD) with high quantum yields of 54.29% and 89.82%, respectively, were investigated and demonstrated to be a reliable, cost-effective, and naked-eye fluorescent probe for the detection of dopamine, a neurotransmitter, in human serum fluids. The current study is well supported by a comprehensive synthesis approach and has been described utilizing a variety of microscopic and spectroscopic techniques. The discovered approach is time and pH dependent, and it provides a robust platform for specifically detecting aberrant dopamine levels using a fluorescence quenching mechanism. Dopamine detection limits for CD were calculated to be 5.54 µM for CD and 5.12 µM for NCD, respectively. The fluorescence quenching shows a linear continuous trend with a range within 3.3-500 µM and 3.3-400 µM of dopamine concentration for CD and NCD respectively. To further verify the sensitivity of CD and NCD as fluorescent probes, interference studies in the presence of different biological components were also studied and validated. This work shows that carbon-based nanomaterials and their doped nanostructures, due to their high fluorescence, have significant potential as fluorescent probes in neurological disease diagnosis as they display high selectivity, sensitivity and fast responses in the real time spectroscopic detection of dopamine in human fluid samples.

Systematic spectroscopic investigation of structural changes and corona formation of bovine serum albumin over magneto-fluorescent nanoparticles.

Magneto-fluorescent nanoparticles have attracted great attention because of their dual nature as multimodal imaging probes in various biomedical applications. Particulary, it is desirable to understand how these nanoparticles interact with human serum proteins before they are used in biological systems. In this work, the physiological interactions between magneto-fluorescent nanoparticles (MFNPs) and bovine serum albumin (BSA) were systematically investigated. The present observations identified that the collision of MFNPs and BSA caused fluorescence quenching of BSA. Steady state fluorescence, lifetime and anisotropy measurements in the presence of MFNPs supported dynamic quenching of the BSA emission. Furthermore, in the presence of MFNPs, the conformation changes in the BSA structure indicate merely the secondary structural changes. The findings demonstrated that random interactions and hydrophobic forces play a major role in the dynamic quenching. Further, subsequent coating of BSA over MFNPs result in protein corona formation, as is evident through spectroscopic measurements. In light of the present work, MFNPs could serve a purpose in magnetic separation and optical detection of serum proteins from blood plasma in real-time disease diagnosis.

Fluorescent Mantle Carbon Coated Core-Shell SPIONs for Neuroengineering Applications.

Superparamagnetic iron oxide nanoparticles (SPIONs) have been used for a variety of biomedical applications, from multimodal imaging to the mechanical activity of cells and tissues. Herein, we present fluorescently mantled carbon coated core-shell superparamagnetic iron oxide nanoparticles (FC-SPIONs) as an excellent material to promote the neuronal differentiation and neuronal network outgrowth in neural tissue engineering applications. Morphological, structural, and functional group characterizations were systematically investigated. FC-SPIONs showed superior magnetic and inherent fluorescence characteristic properties. Furthermore, FC-SPIONs interactions against neuronal PC12 cells showed promising results and deliberate their potential for significant applications in neuroengineering. Interestingly, FC-SPIONs were assessed as biocompatible and promoted the neuronal PC12 cell differentiation process. Accompanied by these results, network outgrowth and branching patterns of neuronal processes can be regulated using FC-SPIONs. Importantly, FC-SPIONs are promising due to their biocompatibility and selective affinity toward neuronal cells, paving the way for neuronal differentiation and outgrowth and neuronal therapeutics in neuroengineering applications.

Bimetallic Metal Organic Frameworks as Magnetically Separable Heterogeneous Catalysts and Photocatalytic Dye Degradation.

A new bimetallic MOF (BMOF) has been synthesized using iron and zinc as inorganic metal nodes and 1,4-benzenedicarboxylic acid (BDC) as the organic linker molecule. BMOF was confirmed by single-crystal X-ray diffraction (SCXRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy high-angle annular dark-field imaging (TEM-HAADF), field emission scanning electron microscopy energy-dispersive X-ray analysis (FESEM-EDX), vibrating sample magnetometry (VSM) and inductively coupled plasma mass spectrometry (ICP-MS) analysis. The synthesized BMOF shows excellent optical and magnetic properties. BMOF acts as a heterogeneous catalyst and shows high catalytic activity towards bis(indolyl)methane synthesis and photocatalytic degradation of methylene blue (MB) under visible-light illumination.

High melting lipid based approach for drug delivery: solid lipid nanoparticles.

Poor solubility of newly developed drug molecules is the main problem in recent drug discovery research, so novel drug delivery approaches are being used to deliver these molecular entities for pharmacological action. Colloidal carriers (emulsion, suspensions, liposomes, polymer nanoparticles and solid lipid nanoparticles) have been used to administer poorly soluble drugs, but solid lipid nanoparticles are found to be the most reliable carriers for this type of drugs due to its advantages over other carriers. Solid lipid nanoparticles have the potential to solve the drug delivery problems with safe excipients used in its formulation. In this review all the aspects of solid lipid nanoparticles production, stability, characterization, differentiation based on route, preservation and storage have been discussed.

Preparation and characterization of Paliperidone loaded solid lipid nanoparticles.

Solid lipid nanoparticles were prepared and studied for the possibility of entrapment of Paliperidone (PPN) an antipsychotic drug that can be used for the treatment of schizophrenia. Here we report the preparation of Paliperidone loaded solid lipid particles (SLNs) with Capmul GMS 50 K as lipid vehicle. SLNs were stabilized by a surfactant namely sodium deoxycholate which can also act as permeability enhancer. Final size of SLNs produced were approximately 200 nm which was confirmed by dynamic light scattering (DLS), atomic force microscopy (AFM) and transmission electron microscopy (TEM). SLNs appeared spherical in TEM images while dough nut like shape was observed by AFM. The entrapment efficiency of this system was found to be 55% with 4.15% of drug loading in lipid matrix. Structural characterization of SLNs by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD) and differential scanning calorimetric (DSC) analysis revealed that, there was no interaction of PPN with lipid and PPN was well dispersed in the lipid matrix without any crystallization.

Mouse cremaster venules are predisposed to light/dye-induced thrombosis independent of wall shear rate, CD18, ICAM-1, or P-selectin.

OBJECTIVE: Microvascular adhesion of platelets to endothelium occurs in response to various inflammatory stimuli, and in venules is often accompanied by adherent leukocytes. In a light/dye injury model, platelet adhesion and thrombi occur preferentially in venules, though the reasons for this predisposition are unknown. The authors sought to determine whether lower wall shear rates or leukocyte-endothelial interactions accounted for preferential platelet thrombi formation in venules relative to arterioles. METHODS: A light/dye injury model of microvascular thrombosis was used in the mouse cremaster microcirculation. RESULTS: In wild-type mice (n = 17), the time to form microvascular platelet aggregates was delayed in arterioles by 3.1-fold relative to venules (p <.0001). However, arterioles with spontaneously low wall shear rates, as well as arterioles manipulated to reduce wall shear rate to venous levels, still had delayed thrombosis as compared to venules. Similarly, in animals deficient in CD18, P-selectin, or ICAM-1, the time to form platelet thrombi in arterioles was >3.0-fold higher than in venules. CONCLUSIONS: Mouse cremaster venules are predisposed to light/dye-induced microvascular thrombosis. The data suggest that functional differences between arteriolar and venular endothelial cells (independent of wall shear rate and of CD18, P-selectin, and ICAM-1) account for the venular predisposition to thrombosis.