Biomaterial Database

Preparation, circular dichroism induced helical conformation and optical property of chitosan acid salt complexes for biomedical applications. 2009

Jay Singh, and P K Dutta

Department of Chemistry, Motilal Nehru National Institute of Technology, Allahabad 211004, India.

The efficient procedure for preparation of chitosan acid complexes containing aspartic acid, benzilic acid and terephthalic acid moieties in isopropyl alcohol under mild condition has been demonstrated. The ionic complexation between chitosan and the acid is confirmed by FTIR and 1H NMR spectroscopy. The circular dichroism (CD) spectra of chitosan/aspartic acid complex showed negative (at lambda=312) band, chitosan/benzilic acid and chitosan/terephthalic complexes showed positive (at lambda=286 and 315 nm) band in DMSO, indicating that the polymers adopted helical (left-handed and last two right-handed) secondary structure. The inversion of the CD pattern in chitosan acid salt complexes suggests that there is a change in the chiral structure of the polymer system. Some physical properties and surface morphology were analyzed by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetry (TG) and scanning electron microscopy (SEM). Optical properties of chitosan derivatives are evaluated by photoluminescence (PL) spectroscopy which showed red shift. The introduction of acid moieties into chitosan increases the solubility in most of the organic solvents, which opens new perspectives for the employment of chitosan-based biohybrid in biomedical applications.

UI	MeSH Term	Description	Entries
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D009682	Magnetic Resonance Spectroscopy	Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).	In Vivo NMR Spectroscopy,MR Spectroscopy,Magnetic Resonance,NMR Spectroscopy,NMR Spectroscopy, In Vivo,Nuclear Magnetic Resonance,Spectroscopy, Magnetic Resonance,Spectroscopy, NMR,Spectroscopy, Nuclear Magnetic Resonance,Magnetic Resonance Spectroscopies,Magnetic Resonance, Nuclear,NMR Spectroscopies,Resonance Spectroscopy, Magnetic,Resonance, Magnetic,Resonance, Nuclear Magnetic,Spectroscopies, NMR,Spectroscopy, MR
D002152	Calorimetry, Differential Scanning	Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.	Differential Thermal Analysis, Calorimetric,Calorimetric Differential Thermal Analysis,Differential Scanning Calorimetry,Scanning Calorimetry, Differential
D002236	Carbohydrate Conformation	The characteristic 3-dimensional shape of a carbohydrate.	Carbohydrate Linkage,Carbohydrate Conformations,Carbohydrate Linkages,Conformation, Carbohydrate,Conformations, Carbohydrate,Linkage, Carbohydrate,Linkages, Carbohydrate
D002942	Circular Dichroism	A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Circular Dichroism, Vibrational,Dichroism, Circular,Vibrational Circular Dichroism
D012492	Salts	Substances produced from the reaction between acids and bases; compounds consisting of a metal (positive) and nonmetal (negative) radical. (Grant & Hackh's Chemical Dictionary, 5th ed)	Salt
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities
D013818	Thermogravimetry	Technique whereby the weight of a sample can be followed over a period of time while its temperature is being changed (usually increased at a constant rate).	Thermogravimetries
D014961	X-Ray Diffraction	The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Xray Diffraction,Diffraction, X-Ray,Diffraction, Xray,Diffractions, X-Ray,Diffractions, Xray,X Ray Diffraction,X-Ray Diffractions,Xray Diffractions
D017550	Spectroscopy, Fourier Transform Infrared	A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.	FTIR,Fourier Transform Infrared Spectroscopy,Spectroscopy, Infrared, Fourier Transform