Browsing by Author "Narayanan, N"

Now showing 1 - 5 of 5
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    Aggregation induced Raman scattering of squaraine dye: Implementation in diagnosis of cervical cancer dysplasia by SERS imaging
    (BIOSENSORS & BIOELECTRONICS, 2015) Narayanan, N; Karunakaran, V; Paul, W; Venugopal, K; Sujathan, K; Maiti, KK
    The extent of squaraine dye aggregation that reflects on surface enhanced Raman signal scattering (SERS) intensity upon adsorption on nano-roughened gold surface has been investigated. Here we have synthesized a serious of six squaraine dyes consisting of two different electron donor moiety i.e. 1,1,2-trimethyl-1H-benzo[elindole and 2-methylbenzo[d]thiazole which modulates the chemisorptions and hydrophobicity being designated as SQ1, SQ2, SQ3, SQ4, SQ5 and SQ6. Interestingly, SQ2 (mono lipoic acid appended), SQ5 and SQ6 (conjugated with hexyl and dodecyl side chain) squaraine derivatives having more tendency of aggregation in DMSO-water mixed solvent showed significant increase of Raman scattering in the fingerprint region when chemisorbed on spherical gold nanoparticles. Two sets of SERS nanotags were prepared with colloidal gold nanoparticle (Au-NPs size: 40 nm) by incorporating Raman reporters SQ2 and SQ5 followed by thiolated PEG encapsulation (SH-PEG, SH-PEG-COOH) denoted as AuNPs-SQ2-PEG and AuNPs-SQ5-PEG. Further conjugation of these nanotag with monoclonal antibodies specific to over expressed receptors, EGFR and p16/Ki-67 in cervical cancer cell, HeLa showed prominent SERS mapping intensity and selectivity towards cell surface and nucleus. The fast and accurate recognition obtained by antibody triggered SERS-nanotag has been compared with conventional time consuming immunocytochemistry technique which prompted us to extend further investigation using real patient cervical smear sample for a non-invasive, ultrafast and accurate diagnosis. (C) 2015 Elsevier B.V. All rights reserved.
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    In vitro characterization of differently processed decellularised bovine pericardium
    (J Livestock Science, 2016-08) Suvaneeth, P; Divakaran, NN; Ramachandra, UP; Narayanan, N; Abraham, MJ; Divya, C; Martin, J
    The efficacy of two different in vitro protocols for the decellularisation of bovine pericardium has been evaluated in this experiment. The pericardia were decellularised using a non-detergent based proprietary enzymatic protocol and a biodetergent (deoxycholic acid) based new protocol. The in vitro characterisation to estimate the in vivo stability was done using histological characterisation, residual DNA analysis, uniaxial tensile testing, contact angle measurement and collagenase susceptibility. The results indicated that the newr detergent based protocol was equally effective in inducing decellularisation and produce similar in vitro characteristics as in enzymatically processed pericardium, and hence can be used for in vivo evaluation and experimental studies.
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    Investigation of apoptotic events at molecular level induced by SERS guided targeted theranostic nanoprobe
    (NANOSCALE, 2016) Narayanan, N; Nair, LV; Karunakaran, V; Joseph, MM; Nair, JB; Ramya, AN; Jayasree, RS; Maiti, KK
    Herein, we have examined distinctive structural and functional variations of cellular components during apoptotic cell death induced by a targeted theranostic nanoprobe, MMP-SQ@GNR@LAH-DOX, which acted as a SERS "on/off" probe in the presence of a MMP protease and executed synergistic photothermal chemotherapy, as reflected by the SERS fingerprinting, corresponding to the phosphodiester backbone of DNA.
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    Laceration of atrial septum during balloon sizing of atrial septal defect
    (EUROPEAN JOURNAL OF ECHOCARDIOGRAPHY, 2007) Sivasankaran, S; Harikrishnan, S; Narayanan, N; Jaganmohan, T
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    Nanotheranostic Probe Built on Methylene Blue Loaded Cucurbituril [8] and Gold Nanorod: Targeted Phototherapy in Combination with SERS Imaging on Breast Cancer Cells
    (Journal of Physical Chemistry B, 2021-12) Narayanan, N; Kim, JH; Santhakumar, H; Joseph, MK; Karunakaran, V; Shamjith, S; Saranya, G; Sujai, PT; Jayasree, RS; Burman, I; Maiti, KK
    Recent advancements in a nanoarchitecture platform for safe and effective targeted phototherapy in a synergistic fashion is an absolute necessity in localized cancer therapy. Photothermal and photodynamic therapies (PTT and PDT) are considered as the most promising localized therapeutic intervention for cancer management as they have no long-term side effects and are minimally invasive and affordable. Herein, we have demonstrated a tailor-made nanotheranostic probe in which macrocyclic host cucurbituril [8] (CB[8]) is placed as a glue between two gold nanorods (GNRs) within ∼3 nm gaps in linear nanoassemblies with exquisitely sensitive plasmonics that exert combined phototherapy to investigate the therapeutic progression on human breast cancer cells. Photosensitizer methylene blue was positioned on CB[8] to impart the PDT effect, whereas GNR was responsible for PTT on a single laser trigger ensuring the synchronized phototherapy. Furthermore, the nanoconstruct was tagged with targeting anti-Her2 monoclonal antibody (MB-CB[8]@GNR-anti-Her2) for localized PTT and PDT on Her2 positive SKBR3 cells, subsequent cellular recognition by surface-enhanced Raman spectroscopy (SERS) platform, and further assessment of the combined intracellular phototherapy. Hence, the current strategy is definitely marked as a proof-of-concept straightforward approach that implies the perfect nature of the combined phototherapy to achieve an efficient cancer treatment.