title: Agarose functionalization: Synthesis of PEG-agarose amino acid nano-conjugate - its structural ramifications and interactions with BSA in a varying pH regime.
abstract: In a rapid one-step method protein-mimicking large agarose amino acid framework (AAE; GPC 156.7kDa) was conjugated with polyethylene glycol (PEG 9kDa) affording nano-sized PEGylated amphoteric agarose (PEG-AAE; <10nm; DLS) containing amino, carboxyl and ester groups [overall degree of substitution (DS) 0.91]. The PEG groups were at the residual free carboxylic acid groups of succinate half-ester moiety at C-6 positions of the 1, 3 β-d-galactopyranose moieties of AAE. This new nano-sized PEG-AAE performed like a giant protein conjugate (GPC 331.2kDa) and exhibited pH-responsive interconversion between the triple helix and single-stranded random structures (optical rotatory dispersion) presenting a mixed solubility pattern like random coil (soluble), helical (soluble) and aggregate (precipitation) formations. Circular dichroism studies showed its pH-dependent complexation and decomplexation with bovine serum albumin (BSA). Such pH-responsive PEG-conjugate may be of pronounced therapeutic potential in the area of pharmacology as well as in sensing applications.
authors.affiliation: Natural Product and Green Chemistry Division, CSIR-Central Salt & Marine Chemicals Research Institute, G. B. Marg, Bhavnagar, 364002 Gujarat, India.
authors.forename: Nishith A
authors.initials: NA
authors.lastname: Chudasama
authors.affiliation: Natural Product and Green Chemistry Division, CSIR-Central Salt & Marine Chemicals Research Institute, G. B. Marg, Bhavnagar, 364002 Gujarat, India; Academy of Scientific & Innovative Research, Anusandhan Bhavan, 2 Rafi Marg, New Delhi 110001, India.
authors.forename: Kamalesh
authors.initials: K
authors.lastname: Prasad
authors.affiliation: Marine Biotechnology and Ecology Division, CSIR-Central Salt & Marine Chemicals Research Institute, G. B. Marg, Bhavnagar, 364002 Gujarat, India; Academy of Scientific & Innovative Research, Anusandhan Bhavan, 2 Rafi Marg, New Delhi 110001, India. Electronic address: siddhantaarupk@rediffmail.com.
authors.forename: Arup Kumar
authors.initials: AK
authors.lastname: Siddhanta
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D002417:Cattle; D060326:Chemistry Techniques, Synthetic; D006863:Hydrogen-Ion Concentration; D049329:Nanostructures / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D011485:Protein Binding; D012685:Sepharose / Q000138:chemical synthesis* / Q000737:chemistry* / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D012710:Serum Albumin, Bovine; D011092:Polyethylene Glycols; D012685:Sepharose
keywords: BSA binding; Nano-protein conjugate; PEG; PEG-agarose amino acid; PEGylation