𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Hydrogen Bonding Structure and Stability of α-Chitin Studied by 13C Solid-State NMR

✍ Scribed by Tsunenori Kameda; Mitsuhiro Miyazawa; Hiroshi Ono; Mitsuru Yoshida

Publisher
John Wiley and Sons
Year
2005
Tongue
English
Weight
94 KB
Volume
5
Category
Article
ISSN
1616-5187

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

Summary: The structure and stability of hydrogen bonds in α‐chitin were investigated by ^13^C solid‐state NMR measurements at different temperatures. Splitting of the carbonyl carbon signal for α‐chitin was interpreted as two types of hydrogen bonding; the peaks at 173.5 and 175.8 ppm were assigned, respectively, to a carbonyl carbon hydrogen bonded exclusively to the NH group and a carbonyl carbon hydrogen‐bonded to both NH and C(6)OH groups. Approximately 60% of carbonyl groups exclusively contributed to the intermolecular hydrogen bonding and ca. 40% of them to the combination of intermolecular and intramolecular hydrogen bonding. Internal rotation around the C(5)–C(6) bond was detected at 55 °C.

^13^C CP/MAS NMR spectrum of chitin (A) and decomposed spectrum in the CO region (B).

magnified image^13^C CP/MAS NMR spectrum of chitin (A) and decomposed spectrum in the CO region (B).

📜 SIMILAR VOLUMES

Conformation of drawn poly(trimethylene
Conformation of drawn poly(trimethylene terephthalate) studied by solid-state 13C NMR
✍ Tsunenori Kameda; Mitsuhiro Miyazawa; Shigemitsu Murase 📂 Article 📅 2004 🏛 John Wiley and Sons 🌐 English ⚖ 142 KB

## Abstract The change in the conformation of the flexible OCH~2~CH~2~CH~2~O segment of poly(trimethylene terephthalate) (PTT) monofilament caused by drawing was investigated by means of the γ‐__gauche__ effect on the ^13^C solid‐state NMR chemical shift of the internal methylene carbon, combin

Structure of GlyGly peptide in the cryst
Structure of GlyGly peptide in the crystalline state as studied by X-ray diffraction and solid state 13C-NMR methods
✍ T. Kameda; N. Takeda; S. Ando; I. Ando; D. Hashizume; Y. Ohashi 📂 Article 📅 1998 🏛 Wiley (John Wiley & Sons) 🌐 English ⚖ 140 KB 👁 2 views

A new type of crystal of glycylglycine (GlyGly) hydrate was crystallized from an aqueous solution, and the structure of the crystal has been determined by x-ray diffraction. The crystal is monoclinic, and the space group is C2/c, with the cell constants of a Å 15.941(2) A ˚, b Å 4.774(2) A ˚, c Å 19

Phase transition of L-Ser monohydrate cr
Phase transition of L-Ser monohydrate crystal studied by 13C solid-state NMR
✍ Tsunenori Kameda; Hidetoshi Teramoto 📂 Article 📅 2006 🏛 John Wiley and Sons 🌐 English ⚖ 351 KB

## Abstract We used gravimetric analysis (GA) and ^13^C solid‐state nuclear magnetic resonance (NMR) to study solid‐phase transition from the transparent single crystal of L‐serine (L‐Ser) monohydrate to a turbid powder. We found that L‐Ser monohydrate loses water molecules and transforms into an a

Variability of cork from Portuguese Quer
Variability of cork from Portuguese Quercus suber studied by solid-state 13C-NMR and FTIR spectroscopies
✍ M. H. Lopes; A. S. Barros; C. Pascoal Neto; D. Rutledge; I. Delgadillo; A. M. Gi 📂 Article 📅 2001 🏛 Wiley (John Wiley & Sons) 🌐 English ⚖ 199 KB 👁 2 views

## Abstract A new approach is presented for the study of the variability of Portuguese reproduction cork using solid‐state ^13^C‐NMR spectroscopy and photoacoustic (PAS) FTIR (FTIR‐PAS) spectroscopy combined with chemometrics. Cork samples were collected from 12 different geographical sites, and th