Thermally induced irreversible conformational changes in collagen probed by optical second harmonic generation and laser-induced fluorescence

Theodossiou, T; Rapti, GS; Hovhannisyan, V; Georgiou, E; Politopoulos, K; Yova, D

dc.contributor.author	Theodossiou, T	en
dc.contributor.author	Rapti, GS	en
dc.contributor.author	Hovhannisyan, V	en
dc.contributor.author	Georgiou, E	en
dc.contributor.author	Politopoulos, K	en
dc.contributor.author	Yova, D	en
dc.date.accessioned	2014-03-01T01:18:26Z
dc.date.available	2014-03-01T01:18:26Z
dc.date.issued	2002	en
dc.identifier.issn	0268-8921	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/15008
dc.subject	Collagen	en
dc.subject	Fluorescence	en
dc.subject	Gelatine	en
dc.subject	Second harmonic generation	en
dc.subject	Thermal denaturation	en
dc.subject.classification	Engineering, Biomedical	en
dc.subject.classification	Surgery	en
dc.subject.other	collagen	en
dc.subject.other	collagen fibril	en
dc.subject.other	neodymium	en
dc.subject.other	nitrogen	en
dc.subject.other	animal tissue	en
dc.subject.other	article	en
dc.subject.other	cattle	en
dc.subject.other	collagen degradation	en
dc.subject.other	conformational transition	en
dc.subject.other	differential scanning calorimetry	en
dc.subject.other	environmental temperature	en
dc.subject.other	fluorescence	en
dc.subject.other	laser	en
dc.subject.other	laser surgery	en
dc.subject.other	mathematical analysis	en
dc.subject.other	neodymium laser	en
dc.subject.other	non invasive measurement	en
dc.subject.other	nonhuman	en
dc.subject.other	optics	en
dc.subject.other	phase transition	en
dc.subject.other	priority journal	en
dc.subject.other	protein tertiary structure	en
dc.subject.other	second harmonic generation	en
dc.subject.other	spectral sensitivity	en
dc.subject.other	temperature measurement	en
dc.subject.other	thermal injury	en
dc.subject.other	triple helix	en
dc.subject.other	Animals	en
dc.subject.other	Cattle	en
dc.subject.other	Collagen	en
dc.subject.other	Fluorescence	en
dc.subject.other	Heat	en
dc.subject.other	Lasers	en
dc.subject.other	Protein Conformation	en
dc.subject.other	Protein Denaturation	en
dc.subject.other	Spectrometry, Fluorescence	en
dc.title	Thermally induced irreversible conformational changes in collagen probed by optical second harmonic generation and laser-induced fluorescence	en
heal.type	journalArticle	en
heal.identifier.primary	10.1007/s10103-002-8264-7	en
heal.identifier.secondary	http://dx.doi.org/10.1007/s10103-002-8264-7	en
heal.language	English	en
heal.publicationDate	2002	en
heal.abstract	Irreversible thermal conformational changes induced to collagen have been studied by optical methods. More specifically, second harmonic generation (SHG) from incident nanosecond Ng:YAG 1064 mn radiation and laser-induced fluorescence by 337 nm, pulsed nanosecond nitrogen laser excitation, at 405, 410 and 415 nm, emission wavelengths were registered at eight temperatures (40degrees, 50degrees, 55degrees, 60degrees, 65degrees, 70degrees, 75degrees and 80degreesC) and normalised with respect to the corresponding values at the ambient temperature of 30degreesC. The heating protocol used in this work, was selected to monitor only permanent changes reflecting in the optical properties of the samples under investigation. In this context, the SHG, directly related to the collagen fibril population in triple helix conformation, indicated on irreversible phase transition around 64degreesC. On the other hand fluorescence related to the destruction of cross-linked chromophores in collagen, some of which are related to the triple helix tertiary structure, also indicated a permanent phase transition around 63degreesC. These results are in agreement with previous results from studies with differential scanning calorimetry. However SHG and fluorescence, being non-invasive optical methods are expected to have a significant impact in the fields of laser ablative surgery and laser tissue welding.	en
heal.publisher	SPRINGER-VERLAG LONDON LTD	en
heal.journalName	Lasers in Medical Science	en
dc.identifier.doi	10.1007/s10103-002-8264-7	en
dc.identifier.isi	ISI:000174402500008	en
dc.identifier.volume	17	en
dc.identifier.issue	1	en
dc.identifier.spage	34	en
dc.identifier.epage	41	en