Potential therapeutic application of gold nanoparticles in B-chronic lymphocytic leukemia (BCLL): enhancing apoptosis

B-Chronic Lymphocytic Leukemia (CLL) is an incurable disease predominantly characterized by apoptosis resistance. We have previously described a VEGF signaling pathway that generates apoptosis resistance in CLL B cells. We found induction of significantly more apoptosis in CLL B cells by co-culture with an anti-VEGF antibody. To increase the efficacy of these agents in CLL therapy we have focused on the use of gold nanoparticles (GNP). Gold nanoparticles were chosen based on their biocompatibility, very high surface area, ease of characterization and surface functionalization. We attached VEGF antibody (AbVF) to the gold nanoparticles and determined their ability to kill CLL B cells. Gold nanoparticles and their nanoconjugates were characterized using UV-Visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). All the patient samples studied (N = 7) responded to the gold-AbVF treatment with a dose dependent apoptosis of CLL B cells. The induction of apoptosis with gold-AbVF was significantly higher than the CLL cells exposed to only AbVF or GNP. The gold-AbVF treated cells showed significant down regulation of anti-apoptotic proteins and exhibited PARP cleavage. Gold-AbVF treated and GNP treated cells showed internalization of the nanoparticles in early and late endosomes and in multivesicular bodies. Non-coated gold nanoparticles alone were able to induce some levels of apoptosis in CLL B cells. This paper opens up new opportunities in the treatment of CLL-B using gold nanoparticles and integrates nanoscience with therapy in CLL. In future, potential opportunities exist to harness the optoelectronic properties of gold nanoparticles in the treatment of CLL

Exploratory studies on azido-bridged complexes (Ni2+ & Mn2+) as dual colourimetric chemosensors for S2- and Ag+: combined experimtal and theoretical outcome with real field application

No description supplie

Chromogenic and fluorogenic Schiff base chemosensor for nano scale level fluoride detection with logical interpretation

Schiff base Organic Frameworks (SOFs) based chemosensor have been synthesized and utilized for recognization of biologically relevant fluoride anion. The chemosensor is selective for fluoride (F−) and exhibits reversible UV–Vis response with alternate addition of aluminum (Al3+). Interestingly a fluorescence ‘turn on’ response has been noticed with concomitant addition of fluoride. TICT, PTTS and restricted Cdouble bond; length as m-dashN isomerization has been taken into account in order to explain the florescence ‘turn on’ phenomenon. Significantly, the limit of fluoride detection is nano molar level (∼10 nM). The reversible UV–Vis phenomena have been used for designing AND–NAND–NOT–NOR–OR–XOR–XNOR based complex logic circuit to prepare potential feedstock as ‘Lab-on a-Molecule’

Toxic organic solvent adsorption by a hydrophobic covalent polymer

A low cost easy to construct imine-based covalent polymer (CPCMERI-1) has been successfully prepared via a room temperature Schiff-base condensation reaction. Purposeful use of an electron rich naphthalene moiety as a skeletal unit implants hydrophobicity in the polymer. The contact angle of the hydrophobic covalent polymer coated surface has been found to be as high as 128°. The newly developed CPCMERI-1 has high thermal as well as chemical stability due to the presence of extended π–π conjugation of naphthalene and phenyl rings linked through –CH[double bond, length as m-dash]N– bonds. Taking advantage of the high stability factor and hydrophobicities of the covalent polymer, we have performed liquid phase adsorption of benzene and its electron rich, and electron deficient substituents like toluene and nitrobenzene, respectively. CPCMERI-1 selectively adsorbs benzene although it possesses adsorption affinity towards nitrobenzene and toluene. The strong π–π interaction between the benzene and naphthalene moiety of the polymer is responsible for the adsorption. Surface analysis of CPCMERI-1 before and after adsorption of benzene has been investigated which depicts the surface adsorption phenomena of the analyte. The interaction has been further examined by using DFT-D3 study which reveals that benzene interacts with the host napthalene moiety through π–π interaction. Precise experimentation reveals that CPCMERI-1 exhibits better performance than commercially available activated carbon and some recently reported materials towards adsorption of organic solvents like benzene, toluene, nitrobenzene etc. We expect that our work presented here will herald a new type of polymer as CPCMERI-1 may be a useful adsorbent for removing organic pollutants

Small molecular probe as selective tritopic sensor of Al3+, F− and TNP: Fabrication of portable prototype for onsite detection of explosive TNP

Schiff base organic compound (SOC) has been prepared as a tritopic chemosensor for selective sensing by fluorescence signalling towards ions like Al3+, F− and explosive molecule like TNP. In general, fluorescence like photophysical property has been used for selective detection of analyte where Al3+ and F− show turn-on fluorescence signal at different wavelengths (nm) however, quenching was found with TNP. As a consequence, the chemosensor has become a selective sensor for Al3+, F− and TNP. Reversibility of fluorescence responses for Al3+ and F− are observed in presence of ammonium nitrate and H+ respectively. Similar to the detection of TNP, the detection of explosive like NO3− salts is also essential from homeland security point of view. In the present work, the finding of reversible sequential fluorescence response can be promoted for fabrication of next generation AND-NOT-OR-NAND-XOR-XNOR-NOR based complex logic circuit which is applicable in photonics, security and other fields including inorganic and material science. In the case of TNP recognition, the pathway mainly depends on non-covalent interaction (quenching constant: 4.4 × 105 M−1) which is even better than the recently reported materials. Detection limit for Al3+, F− and TNP is 1 μM, 3 μM and 500 nM respectively. DFT-D3 has been carried out to explore the host⋯guest interaction along with the structure-property correlation of the present host-guest system. All three guest analytes have been detected inside the living cell at a certain level and in its consequence, the successful in vitro recognition ability of the SOCs inside human cell line HeLa has been explored too. In real time stepping, an easy to operate and an economically affordable pocket prototype has also been fabricated for on spot detection of TNP like explosive

How paramagnetic and diamagnetic LMOCs detect picric acid from surface water and the intracellular environment: a combined experimental and DFT-D3 study

Diamagnetic and Paramagnetic Luminescent Metal Organic Complexes (LMOCs) have been reported for Explosive and Pollutant Nitro Aromatic (epNAC) recognition. The diamagnetic complex shows a highly intense AIE induced by NEt3H+, which disappears after picric acid recognition and subsequently RET will quench the emission intensity. Radical stabilized paramagnetic LMOCs seem to be active but show lower sensing efficiency in comparison with diamagnetic LMOCs. Solution and solid state spectroscopy studies along with DFT-D3 have been executed to enlighten the host guest interaction. Limit of PA detection is ∼250 ppb with a binding constant of 1.2 × 105 M−1. Time-stepping, i.e. intervening in the problem of picric acid recognition from surface water collected from several places of West Bengal, India, has been performed. Mutagenic picric acid has been successfully detected in an aqueous medium inside both prokaryotic and eukaryotic cells at a ppm level using fluorescence microscopy

A Journey towards Salivary Fluoride Level Detection by Suitable Low Cost Chemosensor: From Molecule to Product

Fluoride is a ubiquitous anion and essential for us owing to its ability to protect human body from several health related issues. The safe limit of Fluoride ion for human body is 1.5 ppm, above it the ion becomes toxic and can cause dental‐skeletal fluorosis or urolithiasis. Several countries are facing such health hazard owing to the naturally abundant excess fluoride in ground water. As a consequence, habitants of such fluoride enriched zone needs to monitor the concentration of fluoride in their body by periodic analysis. In this regard, development of a chemosensor which can detect fluoride from human body fluid at easy‐instant‐economic way is an obvious mandate. For the first time, our group has developed a sensor kit and sensor station device as a deliverable product for individual and batch scale detection of salivary fluoride level by colorimetric method. The sensor station is the first device made by interfacing chemical output with electronics and the encrypted signal in digital version could be used as a level of fluoride in saliva. Our journey towards the development of suitable chemosensor for recognition of fluoride from human body fluid is summarized in this account