@article { ISI:000260429100023, title = {Synthesis and biological evaluation of bile acid dimers linked with 1,2,3-triazole and bis-beta-lactam}, journal = {Organic \& Biomolecular Chemistry}, volume = {6}, number = {20}, year = {2008}, month = {OCT}, pages = {3823-3830}, publisher = {ROYAL SOC CHEMISTRY}, type = {Article}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

We report herein the synthesis and biological evaluation of bile acid dimers 11-18 linked through 1,2,3-triazole and bis-beta-lactam. The dimers 11-18 were synthesized using 1,3-dipolar cycloaddition reaction of diazido bis-beta-lactams 3, 4 and terminal alkynes 7-10 derived from cholic acid/deoxycholic acid in the presence of Cu(I) catalyst (click chemistry). These novel molecules were evaluated in vitro for their antifungal and antibacterial activity. Most of the compounds exhibited significant antifungal as well as antibacterial activity against all the tested fungal and bacterial strains. Moreover, their in vitro cytotoxicities towards HEK-293 and MCF-7 cells were also established.

}, issn = {1477-0520}, doi = {10.1039/b809221d}, author = {Vatmurge, Namdev S. and Hazra, Braja G. and Pore, Vandana S. and Shirazi, Fazal and Deshpande, Mukund V. and Kadreppa, Sreenath and Chattopadhyay, Samit and Gonnade, Rajesh G.} } @article { ISI:000259972800039, title = {Synthesis of chimeric tetrapeptide-linked cholic acid derivatives: impending synergistic agents}, journal = {Bioorganic \& Medicinal Chemistry Letters}, volume = {18}, number = {20}, year = {2008}, month = {OCT}, pages = {5512-5517}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Tetrapeptides derived from glycine and beta-alanine were hooked at the C-3 beta position of the modified cholic acid to realize novel linear tetrapeptide-linked cholic acid derivatives. All the synthesized compounds were tested against a wide variety of microorganisms (Gram-negative bacteria, Gram-positive bacteria and fungi) and their cytotoxicity was evaluated against human embryonic kidney (HEK293) and human mammary adenocarcinoma (MCF-7) cell lines. While relatively inactive by themselves, these compounds interact synergistically with antibiotics such as fluconazole and erythromycin to inhibit growth of fungi and bacteria, respectively, at 1-24 mu g/mL. The synergistic effect shown by our novel compounds is due to their inherent amphiphilicity. The fractional inhibitory concentrations reported are comparable to those reported for Polymyxin B derivatives. (c) 2008 Elsevier Ltd. All rights reserved.

}, keywords = {Antimicrobial activity, Cholic acid, Cytotoxicity, Synergism, Tetrapeptide}, issn = {0960-894X}, doi = {10.1016/j.bmcl.2008.09.013}, author = {Bavikar, Sudhir N. and Salunke, Deepak B. and Hazra, Braja G. and Pore, Vandana S. and Dodd, Robert H. and Thierry, Josiane and Shirazi, Fazal and Deshpande, Mukund V. and Kadreppa, Sreenath and Chattopadhyay, Samit} } @article { ISI:000340513400023, title = {Novel fluorescence probe for estimation of cysteine/histidine in human blood plasma and recognition of endogenous cysteine in live Hct116 cells}, journal = {Chemical Communications}, volume = {50}, number = {69}, year = {2014}, month = {SEP}, pages = {9899-9902}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

A new Cu(II)-complex is used as a {\textquoteleft}{\textquoteleft}Turn-On{\textquoteright}{\textquoteright} luminescence probe for specific detection of endogenous Cys in live Hct116 cells and Cys present in human blood plasma without any interference from other amino acids, especially GSH and Hcy. Difference in the mechanistic pathway for Cys and His recognition is discussed.

}, issn = {1359-7345}, doi = {10.1039/c4cc04214j}, author = {Reddy, Upendar G. and Agarwalla, Hridesh and Taye, Nandaraj and Ghorai, Suvankar and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000344244700034, title = {Specific probe for Hg2+ to delineate even H+ in pure aqueous buffer/Hct116 colon cancer cells: Hg(II)-eta(2)-arene pi-interaction and a TBET-based fluorescence response}, journal = {Chemical Communications}, volume = {50}, number = {92}, year = {2014}, month = {SEP}, pages = {14421-14424}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

A new molecular probe that demonstrates a distinct TBET process, induced by the Hg(II)-eta(2)-arene pi-interaction, in pure aqueous medium with a large pseudo-Stokes shift of 200 nm.

}, issn = {1359-7345}, doi = {10.1039/c4cc06740a}, author = {Reddy, Upendar G. and Ramu, Vadde and Roy, Sovan and Taye, Nandaraj and Chattopadhyay, Samit and Das, Amitava} } @article {45884, title = {Fluorescent probe for specific detection of cysteine in the lipid dense region of cells}, journal = {Chemical Communications}, volume = {51}, year = {2015}, month = {SEP}, pages = {16932-16935}, type = {Article}, abstract = {

A new cysteine (Cys) specific chemodosimetric reagent (ER-F) is used in imaging of endogenous Cys localized in the lipid dense region of the live Hct116 cells and the release of Cys within HepG2 cells from a drug following a biochemical transformation. A silica surface, modified with ER-F, could be used for quantitative estimation of Cys present in aqueous solution (pH 7.2) and in a human blood plasma (HBP).

}, issn = {1359-7345}, doi = {10.1039/c5cc07450a}, author = {Ali, Firoj and Anila, H. A. and Taye, Nandaraj and Gonnade, Rajesh G. and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000365462900005, title = {FRET-based probe for monitoring pH changes in lipid-dense region of Hct116 cells}, journal = {Organic Letters}, volume = {17}, number = {22}, year = {2015}, month = {NOV}, pages = {5532-5535}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A rhodamine conjugate (L) with a pseudo Stokes shift of 165 nm is used for probing changes in solution pH under physiological conditions. This reagent is found to be nontoxic, and the luminescence response could be used for imaging changes in endogenous pH induced by dexamethanose (DMT) in the endoplasmic reticulum.

}, issn = {1523-7060}, doi = {10.1021/acs.orglett.5b02568}, author = {Reddy, Upendar G. and Anila, H. A. and Ali, Firoj and Taye, Nandaraj and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000360658000003, title = {New imaging reagents for lipid dense regions in live cells and the nucleus in fixed MCF-7 cells}, journal = {Journal of Materials Chemistry B}, volume = {3}, number = {36}, year = {2015}, month = {AUG}, pages = {7177-7185}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Two new uracil (U) and 5-flurouracil (5-FU) labeled ruthenium(II)-polypyridyl based cellular imaging reagents are reported. Confocal laser scanning microscopic images with live and paraformaldehyde (PFA) fixed MCF-7 cells are examined using these two low-cytotoxic reagents. Experimental results show that these two complexes, appropriately functionalized with U (1) and 5-FU (2), have specific affinity for the lipid dense regions like the endoplasmic reticulum, cell membrane, and cytoplasmic vacuoles in live MCF-7 cells, and dye internalization in these regions happened following an endocytosis pathway. Interestingly, these two complexes are found to be localized in the nucleus of the PFA fixed cells. For fixed cells, presumably the lipid layer disruption helped in the explicit localization of the complexes 1 and 2 in the cell nucleus through specific interaction with cellular DNA. Poor and non-specific internalization of an analogous model complex 3, without having a U or 5-FU moiety, reveals the definite influence of U or 5-FU as well as the role of lipophilicity of the respective complex 1 and 2 in the cellular internalization process. Apart from these, a large Stokes shift (similar to 160 nm) and an appreciably long lived (MLCT)-M-3 excited state (similar to 320 ns) in aq. buffer medium (pH 7.4) are other key features for complexes 1 and 2. Unlike the common nuclear DNA staining reagents like DAPI, these low-cytotoxic reagents are found to be highly stable towards photo-bleaching upon irradiation with 455 nm at the MLCT band for these complexes.

}, issn = {2050-750X}, doi = {10.1039/c5tb01309g}, author = {Ramu, Vadde and Ali, Firoj and Taye, Nandaraj and Garai, Bikash and Alam, Aftab and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000349325400040, title = {New turn on Pd2+-specific fluorescence probe and its use as an imaging reagent for cellular uptake in Hct116 cells}, journal = {Chemical Communications}, volume = {51}, number = {17}, year = {2015}, month = {JAN}, pages = {3649-3652}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

A new coumarin-rhodamine conjugate is used as a specific probe for Pd2+ ions and this could even delineate Pd(II) from Pd(0) or Pd(IV) in aqueous buffer medium (pH similar to 7). Laser confocal microscopic studies reveal that efficient cellular internalization of this reagent helps in imaging the cellular uptake of Pd2+ as low as 0.1 ppm in Hct 116 cells. This reagent could even be used for estimation of Pd2+ in human urine samples.

}, issn = {1359-7345}, doi = {10.1039/c4cc10171e}, author = {Reddy, Upendar G. and Ali, Firoj and Taye, Nandaraj and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000363167900028, title = {Reagent for specific recognition of cysteine in aqueous buffer and in natural milk: imaging studies, enzymatic reaction and analysis of whey protein}, journal = {Chemical Communications}, volume = {51}, number = {85}, year = {2015}, month = {AUG}, pages = {15592-15595}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

We report a new chemodosimetric probe (L) for specific recognition of cysteine (Cys) in aqueous buffer and in whey protein isolated from fresh cow{\textquoteright}s milk. Using this reagent we could develop a luminescence-based methodology for estimation of Cys released from a commercially available Cys-supplement drug by aminoacylase-1 in live cells.

}, issn = {1359-7345}, doi = {10.1039/c5cc04876a}, author = {Anila, H. A. and Reddy, Upendar G. and Ali, Firoj and Taye, Nandaraj and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000363068700007, title = {Specific reagent for Cr(III): imaging cellular uptake of Cr(III) in Hct116 cells and theoretical rationalization}, journal = {Journal of Physical Chemistry B}, volume = {119}, number = {41}, year = {2015}, month = {OCT}, pages = {13018-13026}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A new rhodamine-based reagent (L-1), trapped inside the micellar structure of biologically benign Triton-X 100, could be used for specific recognition of Cr(III) in aqueous buffer medium having physiological pH. This visible light excitable reagent on selective binding to Cr(III) resulted in a strong fluorescence turn-on response with a maximum at similar to 583 nm and tail of that luminescence band extended until 650 nm, an optical response that is desired for avoiding the cellular autofluorescence. Interference studies confirm that other metal ions do not interfere with the detection process of Cr(III) in aqueous buffer medium having pH 7.2. To examine the nature of binding of Cr(III) to L-1, various spectroscopic studies are performed with the model reagent L-1 which tend to support Cr(III)-eta(2)-olefin pi-interactions involving two olefin bonds in molecular probe L-1. Computational studies are also performed with another model reagent L-M to examine the possibility of such Cr(III)-eta(2)-olefin pi-interactions. Presumably, polar functional groups of the model reagent L-M upon coordination to the Cr(III) center effectively reduce the formal charge on the metal ion and this is further substantiated by results of the theoretical studies. This assembly is found to be cell membrane permeable and shows insignificant toxicity toward live colon cancer cells (Hct116). Confocal laser scanning microscopic studies further revealed that the reagent L-1 could be used as an imaging reagent for detection of cellular uptake of Cr(III) in pure aqueous buffer medium by Hct116 cells. Examples of a specific reagent for paramagnetic Cr(III) with luminescence ON response are scanty in the contemporary literature. This ligand design helped us in achieving the turn on response by utilizing the conversion from spirolactam to an acyclic xanthene form on coordination to Cr(III).

}, issn = {1520-6106}, doi = {10.1021/acs.jpcb.5b07565}, author = {Ali, Firoj and Saha, Sukdeb and Maity, Arunava and Taye, Nandaraj and Si, Mrinal Kanti and Suresh, E. and Ganguly, Bishwajit and Chattopadhyay, Samit and Das, Amitava} } @article {43405, title = {Cysteine-specific fluorescent switch for monitoring oxidative stress and quantification of aminoacylase-1 in blood serum}, journal = {Analytical Chemistry}, volume = {88}, year = {2016}, month = {DEC}, pages = {12161-12168}, doi = {10.1021/acs.analchem.6b03066}, author = {Anila, H. A. and Ali, Firoj and Kushwaha, Shilpi and Taye, Nandaraj and Chattopadhyay, Samit and Das, Amitava} } @article {42940, title = {GSH Induced controlled release of levofloxacin from a purpose-built prodrug: luminescence response for probing the drug release in escherichia coli and staphylococcus aureus}, journal = {Bioconjugate Chemistry}, volume = {27}, year = {2016}, month = {SEP}, pages = {2062-2070}, abstract = {

Fluoroquinolones are third-generation broad spectrum bactericidal antibiotics and work against both Gram-positive and Gram-negative bacteria. Levofloxacin (L), a fluoroquinolone, is widely used in anti-infective chemotherapy and treatment of urinary tract infection and pneumonia. The main pathogen for urinary tract infections is Escherichia colt, and Streptococcus pneumoniae is responsible for pneumonia, predominantly a lower respiratory tract infection. Poor permeability of L leads to the use of higher dose of this drug and excess drug in the outer cellular fluid leads to central nervous system (CNS) abnormality. One way to counter this is to improve the lipophilicity of the drug molecule, and accordingly, we have synthesized two new Levofloxacin derivatives, which participated in the spatiotemporal release of drug via disulfide bond cleavage induced by glutathione (GSH). Recent studies with Streptococcus mutants suggest that it is localized in epithelial lining fluid (ELF) of the normal lower respiratory tract and the effective [GSH] in ELF is similar to 430 mu M. E. coli typically cause urinary tract infections and the concentration of GSH in porcine bladder epithelium is reported as 0.6 mM for a healthy human. Thus, for the present study we have chosen two important bacteria (Gram + ve and Gram - ve), which are operational in regions having high extracellular GSH concentration. Interestingly, this supports our design of new lipophilic Levofloxacin based prodrugs, which released effective drug on reaction with GSH. Higher lipophilicity favored improved uptake of the prodrugs. Site specific release of the drug (L) could be achieved following a glutathione mediated biochemical transformation process through cleavage of a disulfide bond of these purpose-built prodrugs. Further, appropriate design helped us to demonstrate that it is possible also to control the kinetics of the drug release from respective prodrugs. Associated luminescence enhancement helps in probing the release of the drug from the prodrug in bacteria and helps in elucidating the mechanistic pathway of the transformation. Such an example is scarce in the contemporary literature.

}, doi = {10.1021/acs.bioconjchem.6b00324}, author = {Pal, Suman and Ramu, Vadde and Taye, Nandaraj and Mogare, Devraj G. and Yeware, Amar M. and Sarkar, Dhiman and Reddy, D. Srinivasa and Chattopadhyay, Samit and Das, Amitava} } @article { ISI:000375346500029, title = {Specific receptor for hydrazine: mapping the in situ release of hydrazine in live cells and in an in vitro enzymatic assay}, journal = {Chemical Communications}, volume = {52}, number = {36}, year = {2016}, month = {MAR}, pages = {6166-6169}, publisher = {ROYAL SOC CHEMISTRY}, type = {Article}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

We report a new chemodosimetric reagent capable of detecting hydrazine in the presence of several other competing amine derivatives and ionic analytes of biological relevance. This reagent has been utilized for real time monitoring of in situ N2H4 release during the metabolism of a crucial tuberculosis drug, isoniazid, in live HepG2 cells. The fluorescence response of the reagent based on its specific reaction with N2H4 is used for developing an in vitro assay for aminoacylase-1.

}, issn = {1359-7345}, doi = {10.1039/c6cc01787h}, author = {Ali, Firoj and Anila, H. A. and Taye, Nandaraj and Mogare, Devraj G. and Chattopadhyay, Samit and Das, Amitava} } @article {43426, title = {Switch-on NIR probe for specific detection of Hg2+ ion in aqueous medium and in mitochondria}, journal = {Inorganic Chemistry}, volume = {55}, year = {2016}, month = {NOV}, pages = {12052-12060}, abstract = {A new 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)-based probe molecule (L) is synthesized for specific binding to Hg2+ ion in physiological condition with an associated luminescence ON response in the near-IR region of the spectrum. Appropriate functionalization in the 5-position of each of two pyrrole moieties with styryl functionality in a BODIPY core helped us in achieving the extended conjugation and a facile intramolecular charge transfer transition with a narrow energy gap for frontier orbitals. This accounted for a poor emission quantum yield for the probe molecule L. Binding to. Hg2+ helped in interrupting the facile intramolecular charge transfer (ICT) process that was initially operational for L. This resulted in a hypsochromic shift of absorption band and a turn-on luminescence response with lambda(Em)(max) of 650 nm on specific binding to Hg2+. Observed spectral changes are rationalized based on quantum chemical calculations. Interestingly, this reagent is found to be localized preferentially in the mitochondria of the live human colon cancer (Hct116) cells. Mitochondria is one of the major targets for localization of He2+, which actually decreases the mitochondrial membrane potential and modifies various proteins having sulfudryl functionality(ies) to cause cell apoptosis. Considering these, ability of the present reagent to specifically recognize Hg2+] in the mitochondrial region of the live Hct116 cells has significance.}, doi = {10.1021/acs.inorgchem.6b02233}, author = {Agarwalla, Hrideshg and Mahajan, Pankaj S. and Sahu, Debashis and Taye, Nandaraj and Ganguly, Bishwajit and Mhaske, Santosh B. and Chattopadhyay, Samit and Das, Amitava} } @article {43492, title = {Oxidant mediated one-step complete conversion of multi-walled carbon nanotubes to graphene quantum dots and their bioactivity against mammalian and bacterial cells}, journal = {Journal of Materials Chemistry B}, volume = {5}, year = {2017}, month = {JAN}, pages = {785-796}, abstract = {It is essential for any antibacterial agent (for clinical applications) that it should have high and selective toxicity towards bacterial cells only, and should not affect the human cells at the concentration used. Graphene quantum dots (GQDs) have emerged as a potential candidate for biomedical applications. However, a simple, low cost, safe, easy to execute, one-step synthesis of uniform and monodispersed GQDs with selective toxicity towards bacterial cells rather than mammalian cells is difficult to achieve. Herein, we have reported a one-step, low-cost, aqueous-phase, simple approach for the complete conversion of multi-walled carbon nanotubes into water-dispersible GQDs with an average size of similar to 3 nm using sodium bismuthate (NaBiO3) as a strong oxidant. The cyclic voltammetry and X-ray photoelectron spectroscopy results indicated that the as-synthesized GQDs suspension possess almost negligible amounts of metallic impurities. The cytotoxicity studies of GQDs against mammalian NIH 3T3 (mouse embryo fibroblast cells) and HEK 293T (human embryonic kidney cells) cells showed that the as-synthesized GQDs were non-cytotoxic up to the concentration of similar to 200 mu g mL(-1). The antimicrobial study shows that the synthesized GQDs have high and selective toxicity towards bacterial cells with a minimum inhibitory concentration of similar to 256 mu g mL(-1) for E. coli and B. subtilis and similar to 512 mu g mL(-1) for P. aeruginosa and S. aureus. The scanning electron microscopy and atomic force microscopy images show extensive cell damage via the perturbation of bacterial cell walls, which was consistent with the enhancement of reactive oxygen species production by almost two times in the bacterial cells upon incubation with similar to 256 mu g mL(-1) GQDs. Our study suggested that the as-synthesized GQDs can be used as a potential candidate for clinical applications as they possess high toxicity to bacterial cells and low toxicity to mammalian cells.}, doi = {10.1039/c6tb02446g}, author = {Biswas, Anupam and Khandelwal, Puneet and Das, Raja and Salunke, Gayatri and Alam, Aftab and Ghorai, Suvankar and Chattopadhyay, Samit and Poddar, Pankaj} } @article {43666, title = {Photo-induced cytotoxicity and anti-metastatic activity of ruthenium(II)-polypyridyl complexes functionalized with tyrosine or tryptophan}, journal = {Dalton Transactions}, volume = {46}, year = {2017}, month = {MAY}, pages = {6634-6644}, abstract = {The synergistic effect of oxygen, light, and photosensitizer (PS) has found applications in medicine for the treatment of cancer through photodynamic therapy (PDT). Induction of apoptosis to cancerous cells will prevent tumor metastasis that spreads cancer cells to the neighboring organs/tissues. Herein, we report the two apoptotic Ru(II)-polypyridyl complexes that are functionalized with pendant amino acid moieties tyrosine (1) and tryptophan (2), respectively. These two water soluble complexes were found to interact strongly (K-a(1) = (1.18 +/- 0.28) x 10(5) M-1 and K-a(2) = (1.57 +/- 0.77) x 10(5) M-1) with CT-DNA. Isothermal titration calorimetry (ITC) studies revealed that these complexes bind to CT-DNA through an entropically driven process. Both the complexes showed photo-induced cytotoxicity and exhibit apoptotic activity under photo-irradiation conditions. The comet assay indicated that these complexes can damage cellular DNA, which is attributed to the significant build-up of O-1(2) level even on irradiation with low intensity light (10 J cm(-2), lambda(Range) 450-480 nm). This photoinduced DNA damage and apoptosis in A549 cells was induced by reactive oxygen species (ROS) and occurred through up-regulation of apoptotic marker caspase-3. Control experiments under dark conditions revealed an insignificant cytotoxicity towards these cells for two photosensitive molecules.}, doi = {10.1039/c7dt00670e}, author = {Ramu, Vadde and Aute, Sunil and Taye, Nandaraj and Guha, Rweetuparna and Walker, Michael G. and Mogare, Devaraj and Parulekar, Apoorva and Thomas, Jim A. and Chattopadhyay, Samit and Das, Amitava} } @article {44559, title = {Retention of anticancer activity of curcumin after conjugation with fluorescent gold quantum clusters: an in vitro and in vivo xenograft study}, journal = {ACS Omega}, year = {2018}, month = {MAY}, abstract = {Gold nanoparticles (Au NPs) have been thoroughly investigated for anti-cancer therapy. However, their undesired high gold content remains a problem when injected into the body for drug delivery applications. In this report, we made an effort to conjugate the curcumin molecules on the surface of gold quantum clusters (Au QCs) by a novel in situ synthesis method which provides an alternative route to not only reduce the metallic content but also increase the water solubility of curcumin and the loading efficiency. Here, curcumin itself acts as a reducing and capping agent for the synthesis of Au QCs. The UV-vis absorption, fluorescence, transmission electron microscopy, and electrospray ionization mass spectrometry results confirmed the synthesis of fluorescent Au QCs. Curcumin-conjugated Au NPs (C-Au NPs) and glutathione (GSH)-conjugated Au QCs (GSH-Au QCs) were also synthesized to visualize the effect of particle size and the capping agent, respectively, on the cytotoxicity to normal and cancer cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that the curcumin-conjugated Au QCs (C-Au QCs) were less cytotoxic to normal cells while almost the same cytotoxic to cancer cells in comparison to curcumin itself, which indicates that curcumin preserves its anticancer property even after binding to the Au QCs. However, C-Au NPs and GSH-Au QCs did not show any cytotoxicity against the normal and cancer cells at the concentration used. The western blot assay indicated that C-Au QCs promote apoptosis in cancer cells. Further, the in vivo study on severe combined immunodeficiency mice showed that C-Au QCs also inhibited the tumor growth efficiently without showing significant toxicity to internal organs.}, doi = {10.1021/acsomega.8b00113}, author = {Khandelwal, Puneet and Alam, Aftab and Choksi, Arpankumar and Chattopadhyay, Samit and Poddar, Pankaj} }