Development of Au@NiO decorated polypyrrole composite for non-Enzymatic electrochemical sensing of cholesterol

A. Nagarajan,V. Sethuraman,T.M. Sridhar,R. Sasikumar 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.120 No.-

In this study, glassy carbon electrode modified by Au@NiO decorated polypyrrole nanocomposite(Au@NiO/PPy-GCE) was fabricated for sensing of cholesterol by non-enzymatic electrochemical method. The composite was characterized by XRD, XPS and morphological studies were examined using FE-SEMand TEM. The redox properties of cholesterol were investigated by cyclic voltammetry. When differentialpulse voltammetry was employed to sense cholesterol, it exhibited a linear range from 1.0 10-5 to1.0 10-4 M, with the sensitivity 7.6 lA lM1 cm2 and detection limit 5.8 x10-7 M. Hence, this compositehas excellent practical applications towards the fabrication of commercial sensors.

Antioxidant Activity and Total Phenolic Content of Triphala churna

E.Jayajothi,T.Elavarasu,M.Hamsaveni,S.K.Sridhar 한국생약학회 2003 Natural Product Sciences Vol.9 No.4

Association of Serum Vitamin D Levels with Bacterial Load in Pulmonary Tuberculosis Patients

( B. Yuvaraj ),( M. G. Sridhar ),( D. N. B. ),( S. Vinod Kumar ),( T. Kadhiravan ) 대한결핵 및 호흡기학회 2016 Tuberculosis and Respiratory Diseases Vol.79 No.3

Background: Vitamin D is known to have diverse effects on various systems in the body. There is evidence to suggest that a link exists between the serum vitamin D status and tuberculosis. The present study was designed to assess the alterations in serum 25-hydroxyvitamin D levels in newly diagnosed sputum acid fast bacilli (AFB) positive pulmonary tuberculosis patients and to study the association, if any, between serum vitamin D levels and different levels of sputum smear positivity. Methods: Serum 25-hydroxyvitamin D levels were estimated in 65 sputum AFB positive pulmonary tuberculosis patients and 65 age and gender-matched healthy controls. Results: The levels of serum 25 hydroxy-vitamin D in tuberculosis patients were not statistically different from the levels of serum 25 hydroxy-vitamin D in healthy controls. However, among patients with pulmonary tuberculosis, there was a significant negative correlation between the levels of serum 25 hydroxy-vitamin D and levels of sputum positivity. Conclusion: Serum vitamin D levels negatively correlates with bacterial load in patients with active pulmonary tuberculosis.

Association of Serum Vitamin D Levels with Bacterial Load in Pulmonary Tuberculosis Patients

Yuvaraj, B.,Sridhar, M.G.,Kumar, S. Vinod,Kadhiravan, T. The Korean Academy of Tuberculosis and Respiratory 2016 Tuberculosis and Respiratory Diseases Vol.79 No.3

Background: Vitamin D is known to have diverse effects on various systems in the body. There is evidence to suggest that a link exists between the serum vitamin D status and tuberculosis. The present study was designed to assess the alterations in serum 25-hydroxyvitamin D levels in newly diagnosed sputum acid fast bacilli (AFB) positive pulmonary tuberculosis patients and to study the association, if any, between serum vitamin D levels and different levels of sputum smear positivity. Methods: Serum 25-hydroxyvitamin D levels were estimated in 65 sputum AFB positive pulmonary tuberculosis patients and 65 age and gender-matched healthy controls. Results: The levels of serum 25 hydroxy-vitamin D in tuberculosis patients were not statistically different from the levels of serum 25 hydroxy-vitamin D in healthy controls. However, among patients with pulmonary tuberculosis, there was a significant negative correlation between the levels of serum 25 hydroxy-vitamin D and levels of sputum positivity. Conclusion: Serum vitamin D levels negatively correlates with bacterial load in patients with active pulmonary tuberculosis.

Antioxidant Activity and Total Phenolic Content of Triphala churna

E. Jayajothi,T. Elavarasu,M. Hamsaveni,S. K. Sridhar 한국생약학회 2004 Natural Product Sciences Vol.10 No.1

Triphala churna is a widely used herbal formulation that contains equal proportion of dried Emblica officinalis, Terminalia chebula and Terminalia belirica. In the Indian system of medicine, it is used in cleaning wounds, urinary disorders, diabetes mellitus, leprosy, constipation, eyedight promotion, piles, and as a rejuvenator. In the present study, the methanolic extract of 5 commercial Triphala was evaluated for antioxidant activity by 1, 1-dipheny1-2-picry-hydrazy1 free redical scavenging method, total phenolic content by Folin-Ciocalter method and gallic acid equivalents (GAE) by high preformance thin layer chromatographic (HPTLC) method. ALL extracts exhibited antioxidant activity significantly. The EC_(50) of the extracts ranged betweed 7.16 to 12.96 μg/ml. The total phenolic content of the extracts was found to be 195.3-296.4 mg of GAE/gm dw. The HPTLC chromatographic data reveal that the content of GAE present in the extract was found to be 7.17-4.11 μg/ml. The study reveals that out of the churnas analysed, C was found to exhibit the mose potent antioxidant activity. A clear correlation between IC₅₀ and content of GAE nor the total phenolic content could be observed. The study reveals that the consumption of Triphala would exert several beneficial effects by virtue of its antioxidant activity.

Nano bioactive HAP-nano bioresorbable β-TCP-PEG composite scaffolds and their biochemical activity for implant applications

K. Kala,M. Sundara Ganeasan,V. Balasubramani,J. Manovasuki,K. Valivittan,T.M. Sridhar,M.R. Kuppusamy 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.2

Recent efforts towards the treatment of bone defects and diseases focus on the development of bone scaffolds. Bioceramicsprovide strength, osteoconductivity and also imparts flexibility and resorbability. In this study, the biodegradable compositeswere fabricated using bioactive nano Hydroxyapatite (n-HAP) and bioresorbable nano β-Tricalcium phosphate (n-β-TCP)taken in 1:1 proportion. The nano composite scaffolds were synthesized using PEG (Poly Ethylene Glycol) by wet precipitationmethod. XRD (X-ray diffraction) confirms the presence of crystalline structure of n-HAP and n-β-TCP within the lattice. FESEM (Field Emission Scanning Electron Microscopy) and EDS (Energy Dispersion X-ray Spectroscopy) confirms the microporous nature and the phase purity of the composite. Further, biochemical studies were carried out using MG-63 Osteoblastcell line to evaluate their sustainability after implantation. The viability of the cells and proliferation rate is evaluated using3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) with different concentration and different incubationperiod. The ALP (Alkaline Phosphotase) test reveals that the composite favours bone regeneration through apatite layerformation. Further studies were carried out to explore the DPPH (1,1-diphenyl-2-picrylhydrazyl) activity on the compositesand results reveals that the composite have an ability to trap the free radicals in the biological surroundings. The antimicrobialstudies indicate that the composites shows no major inhibitory effects towards the most common bone affecting bacteriaStaphylococcus aureus. The studies indicate that the concentration range of the composite is ideal for bone growth and can beused as substituents in the scaffold synthesis for normal and cancerous patients.

Bioresorbable whitlockite coatings on titanium by EPD for biomedical applications

S.P. Vinodhini,B. Venkatachalapathy,T.M. Sridhar 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.9

We have developed biodegradable tri calcium phosphate [Ca3(PO4)2 , β-TCP (whitlockite)] coatings on titanium by surfacemodification to improve the corrosion resistance and biocompatibility. It is a bioresorbable biomaterial and is absorbed forthe formation of new bone tissues. Nano whitlockite powder was synthesized by wet chemical precipitation method and coatedon titanium surfaces by electrophoretic deposition (EPD) from a 1.5% suspension in ethanol. The coatings were carried outat various potentials ranging from 10-50 V and were followed by sintering in vacuum at 800 oC for 1 hr. The crystallinity,vibrational states, surface morphology and composition of the coatings were characterized by XRD, FTIR, and FE-SEM withEDAX respectively. The corrosion resistance of the coating was further evaluated electrochemically to study the stability of thecoatings using open circuit potential-time measurements, potentiodynamic polarization studies and impedance behavior in Ringer’ssolution. The electrochemical corrosion parameters evaluated indicate a shift towards noble direction for the whitlockite coatedsamples in comparison with uncoated titanium metal. Electrochemical impedance spectroscopic investigations revealed the stablenature of the coatings formed. In vitro cytotoxicity studies of the coated material were carried out by MTT assay. The stable natureof the cells confirms the biocompatibility of whitlockite coatings on the titanium substrate.

Molecular Imaging of CXCL12 Promoter-driven HSV1-TK Reporter Gene Expression

Lina Alon,Dara L. Kraitchman,Michael Schär,Angel Cortez,Nirbhay N. Yadav,Rebecca Krimins,Peter V. Johnston,Michael T. McMahon,Peter C. M. van Zijl,Sridhar Nimmagadda,Martin G. Pomper,Jeff W. M. Bulte 한국생물공학회 2018 Biotechnology and Bioprocess Engineering Vol.23 No.2

The C-X-C motif chemokine 12 (CXCL12, SDF1a) and its receptor, CXCR4, play a fundamental role in several biological processes, including hematopoiesis, cardiogenesis, cancer progression, and stem cell migration. Noninvasive monitoring of CXCL12 is highly desirable for optimizing strategies that combine mobilization of therapeutic cells to combat cancer or to assist in cardiac tissue repair after myocardial infarction. Here, we report on an MRI reporter gene system for directly monitoring CXCL12 expression in vivo. Glioma cells and human adipose-derived stem cells (hADSC) were transduced with the herpes simplex virus type-1-thymidine kinase (HSV1- tk) reporter gene expressed under the CXCL12 promoter. HSV1-tk expression resulted in accumulation of the PET tracer [125I]FIAU in vitro and in vivo and induced cell death after ganciclovir treatment. Furthermore, the results show that conditional expression of the reporter gene can be induced by hypoxia in transduced cells. Transduced hADSC were incubated with the CEST MRI probe 5-methyl-5, 6- dihydrothymidine (5-MDHT) and transplanted into swine heart. Transplanted cells were clearly visible on Chemical Exchange Saturation Transfer (CEST) MRI using a 3T clinical scanner. Therefore, we conclude that it is possible to image CXCL12 expression with MRI in a large animal model, opening up a possible route to clinical translation.