title: Fluorescent imino and secondary amino chitosans as potential sensing biomaterials.
abstract: A variety of fluorescent imino and secondary amino chitosans were synthesized under very mild conditions by reaction of the biopolymer amino functions with aromatic aldehydes in an acidified methanolic suspension. Simultaneous reactions of several aldehydes with chitosan were successfully carried out, and kinetic studies showed that 1-pyrenecarboxaldehyde reacts the fastest among them. An unprecedented study on the evaluation of the degree of N-substitution (DS, ranging from 31.7% to 12.0%) for the chitosan Schiff bases by using solid state CPMAS (13)C NMR is performed. A linear correlation between the DS obtained for the secondary amino chitosans by (1)H NMR (55.3-10.2%) and those obtained by CPMAS (13)C NMR (34.4-13.8%) has allowed us to calculate an empirical correlation factor that could be applied on chitosan-based aromatic systems. The new chiral-labelled chitosan derivatives exhibit a stable fluorescent behaviour, which was used to explore solvent sensoring applications.
authors.affiliation: Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, C/Profesor García González 1, 41012 Sevilla, Spain.
authors.forename: Sorel
authors.initials: S
authors.lastname: Jatunov
authors.affiliation: Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, C/Profesor García González 1, 41012 Sevilla, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Franconetti
authors.affiliation: Departamento de Química Física, Facultad de Química, Universidad de Sevilla, C/Profesor García González 1, 41012 Sevilla, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Prado-Gotor
authors.affiliation: Instituto de Estudios Biofuncionales. Dpto. Química Física II. Facultad de Farmacia. Universidad Complutense de Madrid Paseo Juan XXIII 1, 28040 Madrid, Spain.
authors.forename: Angeles
authors.initials: A
authors.lastname: Heras
authors.affiliation: Instituto de Estudios Biofuncionales. Dpto. Química Física II. Facultad de Farmacia. Universidad Complutense de Madrid Paseo Juan XXIII 1, 28040 Madrid, Spain.
authors.forename: Marian
authors.initials: M
authors.lastname: Mengíbar
authors.affiliation: Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, C/Profesor García González 1, 41012 Sevilla, Spain. Electronic address: fcabrera@us.es.
authors.forename: Francisca
authors.initials: F
authors.lastname: Cabrera-Escribano
mesh_terms: D000588:Amines / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry*; D007097:Imines / Q000737:chemistry; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D011721:Pyrenes / Q000737:chemistry; D012545:Schiff Bases / Q000737:chemistry; D012997:Solvents / Q000032:analysis; D013050:Spectrometry, Fluorescence; D013237:Stereoisomerism
chemical_list: D000588:Amines; D007097:Imines; D011721:Pyrenes; D012545:Schiff Bases; D012997:Solvents; C036464:pyrene-1-aldehyde; D048271:Chitosan
keywords: 1-Pyrenecarboxaldehyde (PubChem CID: 232848); 4-Hydroxybenzaldehyde (PubChem CID: 126); 4-N,N-Dimethylamino-1-naphthaldehyde (PubChem CID: 608052); 4-N,N-Diphenylaminobenzaldehyde (PubChem CID: 77846); 4-Nitrobenzaldehyde (PubChem CID: 541); Biphenyl-4-carboxaldehyde (PubChem CID: 76689); Chitosan; Chitosan Schiff Bases; Fluorescence; Secondary Amino Chitosans; Sensing biomaterials; Solid state NMR