@article {42800, title = {Transfer of technology (ToT) document of polyimide binder resins}, year = {2009}, month = {JAN}, author = {Ponrathnam, Surendra and Chelanattukizhakkemadath, Raman Rajan and Dwivedi, Mayank and Chavan. N. N. and Qureshi, Moham and Bhongale, Sunil Sitaram and Rao, Locanindi Hari Sarvothama and Dhansekharan, Janakiraman and Mohan, S. Krishna and Deokar, Sarika Babasaheb and Momin, Mohasin Shamshuddin} } @article { ISI:000273403400066, title = {Adsorption induced enzyme denaturation: the role of polymer hydrophobicity in adsorption and denaturation of alpha-chymotrypsin on allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymers}, journal = {Langmuir}, volume = {26}, number = {2}, year = {2010}, month = {JAN}, pages = {1096-1106}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Effects of changes in hydrophobicity of polymeric support oil structure and activity of alpha-chymotrypsin (E.C.3.4.21.1) have been studied with copolymers of allyl glycidyl ether (AGE) and ethylene glycol dimethacrylate (EGDM) with increasing molar ratio of EGDM to AGE (cross-link density 0.05 to 1.5). The enzyme is readily adsorbed front aqueous buffer at room temperature following Langmuir adsorption isotherms in unexpectedly large amounts (25\% w/w). Relative hydrophobicity of the copolymers has been assessed by studying adsorption of naphthalene and Fmoc-methionine by the series of copolymers from aqueous solutions. Polymer hydrophobicity appears to increase linearly oil increasing cross-link density from 0.05 to 0.25. Further increase in cross-link density Causes a decrease in naphthalene binding but has little effect on binding of Fmoc-Met. Binding of alpha-chymotrypsin to these copolymers follow the trend for Fmoc-methionine binding, rather than naphthalene binding, indicating involvement of polar interactions along with hydrophobic interactions during binding of protein to the polymer. The adsorbed enzyme undergoes extensive denaturation (ca. 80\%) with loss of both tertiary and secondary structure on contact with the copolymers as revealed by fluorescence, CID and Raman spectra of the adsorbed protein. Comparison of enzyme adsorption behavior with Eupergit C, macroporous Amberlite XAD-2, and XAD-7 Suggests that polar interactions of the EGDM ester functional groups with the protein play a significant role in enzyme denaturation.

}, issn = {0743-7463}, doi = {10.1021/la904114u}, author = {Lahari, Challa and Jasti, Lakshmi Swarnalatha and Fadnavis, Nitin W. and Sontakke, Kalpana and Ingavle, Ganesh C. and Deokar, Sarika Babasaheb and Ponrathnam, Surendra} } @article {42793, title = {Amino functionalized oligoimides telechelics}, number = {2922/DEL/2010 A}, year = {2010}, month = {AUG}, type = {India Patents}, abstract = {

This invention relates to a process for the preparation of amino functionalized oligoimide telechelics. More particularly it relates to a process for the preparation of soluble oligoimide prepolymers which can be used as matrix resins that can be rapidly cured to form stable polyimides with amino end functionalities. The amino functionalized oligoimide telechelics are suitable for conversion into three dimensional polymeric systems through condensation chemistry such as reaction with oligo epoxies (epoxy-imide resins), polyacids (polyamide imides) and polyhalogenated compounds (poly amine - imides) to form crosslinked structures having enhanced thermal stability and mechanical strength. The polymers prepared by the process of this invention can be used as materials in advanced composites having high temperature stability.

}, author = {Dwivedi, Mayank and Rao, Locanindi Hari Sarvothama and Reddy, Krishna Mohan Srinivasulu and Dhanasekharan, Janakiraman and Rao, Bevara Madhusudana and Kumar, Sriperambudur Rajesh and Ponrathnam, Surendra and Rajan, Chelanattukizhakkemadath Raman and Deokar, Sarika Babasaheb and Mulani, Khudbudin Baban and Ghorpade, Ravindra V. and Bhongale, Sunil Sitaram and Nalawade, Archana Chetan and Sontakke, Kalpana Vishwanathrao and Shaikh, Wasif Abdul Lateef and Chavan, Nayaku and Qureshi, Mohammed Shadbar and Dhoble, Deepa Arun and Mule, Smita Atmaram and Bhosle, Sonali Madhavrao and Momin, Mohasin Shamshuddin} } @conference {42783, title = {Transfer of technology (ToT) document of ethyl silicate-32}, booktitle = {Transfer of Technology (ToT)/ Technical Documents}, year = {2011}, month = {JAN}, address = {DRDL Hyderabad.}, author = {Ponrathnam, Surendra and Chelanattukizhakkemadath, Raman Rajan and Dwivedi, Mayank and Chavan, Nayaku and Qureshi, Moham and Bhongale, Sunil Sitaram and Rao, Locanindi Hari Sarvothama and Dhanasekharan, Janakiraman and Mohan, S. Krishna and Deokar, Sarika Babasaheb and Momin, Mohasin Shamshuddin} } @conference {42789, title = {Transfer of technology (ToT) document of phenol-aniline-formaldehyde (sf-342a) resins}, booktitle = {Transfer of technology (ToT) document}, year = {2011}, month = {JAN}, address = {DRDL Hyderabad.}, author = {Ponrathnam, Surendra and Chelanattukizhakkemadath, Raman Rajan and Dwivedi, Mayank and Chavan, Nayaku and Qureshi, Moham and Bhongale, Sunil Sitaram and Rao, Locanindi Hari Sarvothama and Dhanasekharan, Janakiraman and Mohan, S. Krishna and Deokar, Sarika Babasaheb and Momin, Mohasin Shamshuddin} } @article { ISI:000298518600028, title = {Adsorption induced enzyme denaturation: the role of protein surface in adsorption induced protein denaturation on allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymers}, journal = {Colloids and Surfaces B-Biointerfaces}, volume = {90}, year = {2012}, month = {FEB}, pages = {184-190}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

The effects of protein size on adsorption and adsorption-induced denaturation of proteins on copolymers of allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) have been studied. Different responses were observed for the amount of protein adsorbed and denatured on the polymer surface for different proteins (trypsin, alchol dehydrogenase from baker{\textquoteright}s yeast (YADH), glucose dehydrogenase (GDH) from Gluconobacter cerinus, and alkaline phosphates from calf intestinal mucosa (CIAP). Protein adsorption on the copolymer with 25\% crosslink density (AGE-25) was dependent not only on the size of the protein but also on the presence of glycoside residues on the protein surface. Adsorption and denaturation of proteins follows the order YADH \> trypsin \> GDH \>\> CIAP although the molecular weights of the proteins follow the order YADH \> CIAP \> GDH \> trypsin. The lack of correlation between amount of adsorbed protein and its molecular weight was due to the presence of glycoside residues on CIAP and GDH which protect the enzyme surface from denaturation. Enzyme stabilities in aqueous solutions of 1-cyclohexyl-2-pyrrolidinone (CHP) correlate well with the trend in denaturation by the copolymer, strongly suggesting that hydrophobic interactions play a major role in protein binding and the mechanism of protein denaturation is similar to that for water-miscible organic solvents. (C) 2011 Elsevier B.V. All rights reserved.

}, keywords = {1-Cyclohexyl-2-pyrrolidinone, Adsorption, Alcohol dehydrogenase, Alkaline phosphatase, allyl glycidyl ether, Denaturation, ethylene glycol dimethacrylate, Glucose dehydrogenase, Trypsin}, issn = {0927-7765}, doi = {10.1016/j.colsurfb.2011.10.022}, author = {Thudi, Lahari and Jasti, Lakshmi Swarnalatha and Swarnalatha, Y. and Fadnavis, Nitin W. and Mulani, Khudbudin Baban and Deokar, Sarika Babasaheb and Ponrathnam, Surendra} } @article {42779, title = {Amino functionalized oligo polyimides with enhanced storage stability}, number = {EP 11817412 A 20111228}, year = {2012}, month = {JUL}, abstract = {

The invention relates to an improved process for the preparation of amino functionalized oligomeric monomeric reactant type polyimides having higher stability. More particularly it relates to a process for the preparation of soluble imide prepolymers, used as matrix resins that can be rapidly cured with multi-functional moieties such as diepoxy, dicarboxyl, anhydride, diisocyanates to form crosslinked structures having enhanced thermal stability and mechanical strength.

}, author = {Dwivedi, Mayank and Rao, Locanindi Hari Sarvothama and Mohan, Srinivasulu Reddy Krishna and Dhanasekharan, Janakiraman and Rao, Bevara Madhusudana and Kumar, Sriperambudur Rajesh and Ponrathnam, Surendra and Rajan, Chelanattukizhakkemadath Raman and Tayal, Rajiv Kumar and Shadbar, Qureshi Mohammed and Chavan, Nayaku and Deokar, Sarika Babasaheb and Mulani, Khudbudin Baban and Ghorpade, Ravindra V. and Bhongale, Sunil Sitaram and Nalawade, Archana Chetan and Sontakke, Kalpana Vishwanathrao and Bhosle, Sonali Madhavrao and Mule, Smita Atmaram and Dhoble, Deepa Arun and John, Aruldoss and Shaikh, Wasif Abdul Lateef and Harikrishna, Reghunathan and Punitharasu, Vellimala and Momin, Mohasin Shamshuddin} } @article { ISI:000297609900010, title = {Enzyme immobilization on epoxy supports in reverse micellar media: prevention of enzyme denaturation}, journal = {Journal of Molecular Catalysis B-Enzymatic}, volume = {74}, number = {1-2}, year = {2012}, month = {JAN}, pages = {54-62}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Immobilization of enzymes such as alpha-chymotrypsin (EC 3.4.21.1), yeast alcohol dehydrogenase (YADH) from Saccharomyces cerevisiae (EC 1.1.1.1) and glucose dehydrogenase (GDH) from Gluconobacter cerinus (EC 1.1.1.119) has been carried out. Copolymers of allyl glycidyl ether (AGE) crosslinked with 25\% ethylene glycol dimethacrylate (EGDM) (25 mg, dry wt) were contacted with the enzymes solubilized in reverse micellar media (0.5-5 mg/mL)(overall) of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) salt in isooctane, and cetyl trimethylammonium bromide (CTAB) in chloroform-isooctane (50:50, v/v). Although the enzymes are readily denatured (\>90\%) after adsorption on the copolymer in aqueous buffers, no such adsorption-induced denaturation takes place in reverse micelles. alpha-Chymotrypsin is remarkably stable in AOT reverse micelles when 0.025 M citrate buffer of pH 9.0 containing 2 mM CaCl2 is used in the water pools instead of Tris-HCl buffer of pH 8.5. It was possible to achieve enzyme concentration of 5 mg/mL in 0.3 M AOT at molar ratio of water to surfactant, (W-0), 30 and to obtain alpha-chymotrypsin loading of 20 mg/g of copolymer. The recovered enzyme solution can be reused with a fresh batch of polymer after supplementing the depleted solution. The immobilized enzyme exhibits excellent stability in aqueous buffers at room temperature and can be recycled several times. YADH is stable in both AOT and CTAB reverse micelles while GDH is stable only in CTAB reverse micelles containing 0.05 M Tris-HCI buffer of pH 8.5. Interestingly, the combination of YADH (2.5 mg/g) and GDH (0.5 mg/g) co-immobilized on the copolymer using CTAB-chloroform-isooctane system can be used for regeneration and recycle of NADPH at least 50 times as exemplified by complete reduction of a prochiral ketoester, ethyl 4-phenyl-2,4-dioxobutyrate (10 mM) to ethyl (R)-2-hydroxy-4-phenylbutyrate (HPB ester) using NADPH (0.2 mM). (C) 2011 Elsevier B.V. All rights reserved.

}, keywords = {allyl glycidyl ether, alpha-Chymotrypsin, ethylene glycol dimethacrylate, Glucose dehydrogenase, Reverse micelles, Yeast alcohol dehydrogenase}, issn = {1381-1177}, doi = {10.1016/j.molcatb.2011.08.014}, author = {Thudi, Lahari and Jasti, Lakshmi Swarnalatha and Swarnalatha, Yalangi and Fadnavis, Nitin W. and Mulani, Khudbudin Baban and Deokar, Sarika Babasaheb and Ponrathnam, Surendra} } @article {42782, title = {Ethyl oligo-silicates with strong acid heterogeneous polymeric catalysts}, number = {PCT/IB2011/002531}, year = {2012}, month = {MAY}, type = {Application}, abstract = {

The present invention provides a process for the synthesis of ethyl silicate with varying silica concentration, by hydrolysing ethyl silicate in varying water concentration in the presence of sulfonated catalysts having a styrene-divinyl benzene backbone. The present invention further relates to the preparation of beaded crosslinked polymers containing sulfonic acid moieties having an interconnected pore structure and surface area up to 400 m2 /g.

}, author = {Bevara, Madhusudana Rao and Bhongale, Sunil Sitaram and Bhosle, Sonali Madhavrao and Chavan, Nayaku and Chelanattukizhakkemadath, Raman Rajan and Deokar, Sarika Babasaheb and Dhoble, Deepa Arun and Dwivedi, Mayank and Ghorpade, Ravindra V. and Harikrishna, Reghunathan and Dhanasekharan, Janakiraman and John, Aruldoss and Locanindi, Hari Sarvothama Rao and Momin, Mohasin Shamshuddin and Mulani, Khudbudin Baban and Mule, Smita Atmaram and Nalawade, Archana Chetan and Punitharasu, Vellimalai and Qureshi, Mohammed Shadbar and Kumar, Tayal Rajiv and Shaikh, Wasif Abdul Lateef and Sontakke, Kalpana Vishwanathrao and Reddy, Krishna Mohan Srinivasulu and Sriperambudur, Rajesh Kumar and Ponrathnam, Surendra} } @article { ISI:000308878400007, title = {Immobilization of enantioselective lipase on soluble supports for kinetic resolution of drug intermediates}, journal = {Journal of Bioactive and Compatible Polymers}, volume = {27}, number = {5}, year = {2012}, month = {SEP}, pages = {499-509}, publisher = {SAGE PUBLICATIONS LTD}, address = {1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND}, abstract = {

The microbial lipase, Arthrobacter sp. lipase (MTCC 5125), from the Indian Institute of Integrative Medicine repository, is known as an effective catalyst for high enantioselective kinetic resolution of drug intermediates. The ABL was immobilized on water-soluble linear supports by covalently binding it to the epoxy groups on the N-vinyl pyrrolidone/allyl glycidyl ether and N-vinyl pyrrolidone/glycidyl methacrylate copolymers. The immobilized lipase, on different soluble supports, had 90-110 mg/g protein binding and 500-700 U/g hydrolysis activities for tributyrin substrate. These copolymers had soluble/insoluble characteristics in different pH ranges, which is an advantage over insoluble copolymers. A soluble polymer at neutral pH provided better accessibility to the immobilized enzyme, which was recovered by precipitation at pH 2-3 for reuse. Kinetic resolution of racemic acyl derivatives of chiral auxiliaries and drug intermediates, namely, phenyl ethanol, aminoalcohol, and fluoxetine intermediate resulted in a significant enhancement in enantioselectivity (99\%).

}, keywords = {Arthrobacter sp lipase, Enantioselectivity, Immobilization, Kinetic resolution, N-vinylpyrrolidone, soluble polymer}, issn = {0883-9115}, doi = {10.1177/0883911512453638}, author = {Chaubey, Asha and Parshad, Rajinder and Taneja, Subhash C. and Deokar, Sarika Babasaheb and Raman, Rajan C. and Ponrathnam, Surendra} } @article { ISI:000335706100026, title = {Comparison of polymer induced and solvent induced trypsin denaturation: the role of hydrophobicity}, journal = {Colloids and Surfaces B-Biointerfaces}, volume = {116}, year = {2014}, month = {APR}, pages = {201-205}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Trypsin adsorption from aqueous buffer by various copolymers of allyl glycidyl ether-ethylene glycol dimethacrylate (AGE-EGDM) copolymer with varying crosslink density increases with increasing crosslink density and the effect slowly wears off after reaching a plateau at 50\% crosslink density. The copolymer with 25\% crosslink density was reacted with different amines with alkyl/aryl side chains to obtain a series of copolymers with 1,2-amino alcohol functional groups and varying hydrophobicity. Trypsin binding capacity again increases with hydrophobicity of the reacting amine and a good correlation between logP(octanol) of the amine and protein binding is observed. The bound trypsin is denatured to the extent of 90\% in spite of the presence of hydrophilic hydroxyl and amino groups. The behavior was comparable to that in mixtures of aqueous buffer and water-miscible organic co-solvents where the solvent concentration required to deactivate 50\% of the enzyme (C-50) is dependent on logP(octanol) of the co-solvent. (C) 2014 Elsevier B.V. All rights reserved.

}, keywords = {Adsorption, Denaturation, Hydrophobicity, Polymer, Trypsin}, issn = {0927-7765}, doi = {10.1016/j.colsurfb.2014.01.002}, author = {Jasti, Lakshmi Swarnalatha and Fadnavis, Nitin W. and Addepally, Uma and Daniels, Siona and Deokar, Sarika Babasaheb and Ponrathnam, Surendra} } @article { ISI:000334421100007, title = {Protein-coated polymer as a matrix for enzyme immobilization: immobilization of trypsin on bovine serum albumin-coated allyl glycidyl ether-ethylene glycol dimethacrylate copolymer}, journal = {Biotechnology Progress}, volume = {30}, number = {2}, year = {2014}, month = {MAR}, pages = {317-323}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymer with 25\% crosslink density (AGE-25) shows excellent bovine serum albumin (BSA) adsorption (up to 16\% (w/w)) at pH 8.0 and the adsorbed BSA is strongly bound. This protein-coated polymer provides a novel matrix with naturally existing functional groups such as thiol, amino, and carboxylic acid that are available for covalent immobilization of functional enzymes. Employing appropriate strategies, trypsin as a model protein was covalently bound to BSA-coated matrix both independently, and in a stepwise manner on the same matrix, with less than 5\% loss of enzyme activity during immobilization. Glutaraldehyde crosslinking after immobilization provide stable enzyme preparation with activity of 510 units/g recycled up to six times without loss of enzyme activity. AFM studies reveal that the polymer surface has protein peaks and valleys rather than a uniform monolayer distribution of the protein and the immobilized enzyme preparation can best be described as polymer supported cross-linked enzyme aggregates (CLEAs). (c) 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:317-323, 2014

}, keywords = {allyl glycidyl ether, Bovine serum albumin, ethylene glycol dimethacrylate, Immobilization, Trypsin}, issn = {8756-7938}, doi = {10.1002/btpr.1871}, author = {Jasti, Lakshmi Swarnalatha and Dola, Sandhya Rani and Kumaraguru, Thenkrishnan and Bajja, Sreedhar and Fadnavis, Nitin W. and Addepally, Uma and Rajdeo, Kishor and Ponrathnam, Surendra and Deokar, Sarika Babasaheb} }