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dc.contributor.authorPsilodimitrakopoulos, Sotiris
dc.contributor.authorAmat Roldán, Iván
dc.contributor.authorLoza Álvarez, Pablo
dc.contributor.authorArtigas García, David
dc.contributor.otherUniversitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions
dc.date.accessioned2010-11-18T11:22:08Z
dc.date.available2010-11-18T11:22:08Z
dc.date.created2010-08
dc.date.issued2010-08
dc.identifier.citationPsilodimitrakopoulos, S. [et al.]. Estimating the helical pitch angle of amylopectin in starch using polarization second harmonic generation microscopy. "Journal of optics (Calcutta)", Agost 2010, p. 12-8.
dc.identifier.issn0970-0374
dc.identifier.urihttp://hdl.handle.net/2117/10342
dc.description.abstractStarch granules are among the brightest natural second harmonic generation (SHG) converters. They basically consist of amylose and amylopectin molecules and the source of the SHG signal is still undetermined. In the present study we perform polarization sensitive SHG (PSHG) imaging of wheat starch granules and we fit the SHG signal variation of each pixel of the PSHG images into a generalized biophysical model. By assuming that the SHG source molecule is a helix with cylindrical symmetry along its long axis, the model extracts the helical pitch angle of the SHG source for every pixel of the image. By displaying the pixel histogram representing this helical pitch angle we found a highly peaked histogram with maximum at θe = 36.1◦ and a width of θe = 9.3◦. This pitch angle corresponds to the strand of the parallel double helical structure, called amylopectin (as measured by a small angle x-ray scattering technique). This demonstrates amylopectin (and not amylose) as the source of SHG in starch. According to our knowledge, this is the first estimation of the amylopectin’s pitch angle in starch using PSHG.
dc.format.extent-3 p.
dc.language.isoeng
dc.subjectÀrees temàtiques de la UPC::Enginyeria de la telecomunicació::Telecomunicació òptica::Fotònica
dc.subjectÀrees temàtiques de la UPC::Enginyeria electrònica::Optoelectrònica::Làser
dc.subject.lcshStarch--Analysis
dc.subject.lcshSecond harmonic generation
dc.subject.lcshImaging systems in biology
dc.subject.lcshAmylopectins--Analysis
dc.titleEstimating the helical pitch angle of amylopectin in starch using polarization second harmonic generation microscopy
dc.typeArticle
dc.subject.lemacMidó
dc.subject.lemacFotònica
dc.contributor.groupUniversitat Politècnica de Catalunya. FOTONICA - Grup de Recerca de Fotònica
dc.identifier.doi10.1088/2040-8978/12/8/084007
dc.description.peerreviewedPeer Reviewed
dc.relation.publisherversionhttp://iopscience.iop.org/2040-8986/12/8/084007/pdf/2040-8986_12_8_084007.pdf
dc.rights.accessRestricted access - publisher's policy
local.identifier.drac2749732
dc.description.versionPostprint (published version)
dc.relation.projectidinfo:eu-repo/grantAgreement/EC/FP7/224338/EU/COMPACT ULTRAFAST LASER SOURCES BASED ON NOVEL QUANTUM DOT STRUCTURES/FAST-DOT
local.citation.authorPsilodimitrakopoulos, S.; Amat, I.; Loza, P.; Artigas, D.
local.citation.publicationNameJournal of optics (Calcutta)
local.citation.startingPage12
local.citation.endingPage8


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