Solid-state¹³C NMR Study of Scleroglucan Polysaccharide. Effect of the Drying Process and Hydration on Scleroglucan Structure and Dynamics

Efficient Catalyst-Free One-Pot Synthesis of Polysaccharide-Polypeptide Hydrogels in Aqueous Solution

“…We also explored the use of water-soluble unprotected αamino acid NCAs, specifically L-α-glutamic acid NCA and Lserine NCA, which were synthesized using a novel watertolerant strategy. 17 Both NCAs reacted with CMC by using the aqueous protocol described above. Upon addition of the NCAs, the solution immediately formed sticky precipitates without transitioning into a suspension or hydrogel.…”

“…This may be attributable to the low aqueous solubility of TFA-Lys NCA. We also explored the use of water-soluble unprotected α-amino acid NCAs, specifically L-α-glutamic acid NCA and l -serine NCA, which were synthesized using a novel water-tolerant strategy . Both NCAs reacted with CMC by using the aqueous protocol described above.…”

“…The contact times and recycle delays were 1.2 ms and 10 s, respectively. 500 transients were collected for the spectrum . FT-IR spectra of polysaccharide samples were collected on a JASCO FT/IR-4700 spectrometer.…”

“…500 transients were collected for the spectrum. 17 FT-IR spectra of polysaccharide samples were collected on a JASCO FT/IR-4700 spectrometer. The samples were ground into powders with KBr and pressed into pellets.…”

NMR Characterization of Carboxymethyl Scleroglucan

“…Controlled oxidation brings the formation of the dialdehyde and the dicarboxylic derivative (sclerox) as a consequence of the ring opening of the glucose in the lateral side. [16] In a preliminary 1 H-NMR characterization [16,[19][20][21] of Scl-CM the position of the carboxymethyl groups in the scleroglucan structure was not investigated. Recently we reported a new strategy to introduce carboxylic groups on the Scl backbone that is based on the reaction of the native polymer with chloroacetic acid in basic conditions.…”