title: Interaction of digestive enzymes with tunable light emitting quantum dots: a thorough Spectroscopic investigation.
abstract: In this article, we have examined the direct spectroscopic and microscopic evidence of efficient quantum dots-α-chymotrypsin (ChT) interaction. The intrinsic fluorescence of digestive enzyme is reduced in the presence of quantum dots through ground-state complex formation. Based on the fluorescence data, quenching rate constant, binding constant, and number of binding sites are calculated under optimized experimental conditions. Interestingly, fluorescence quenching method clearly illustrated the size dependent interaction of MPA-CdTe quantum dots. Conformational change of ChT was traced using synchronous fluorescence measurements, circular dichroism and FTIR spectroscopic methods. Furthermore, the AFM results revealed that the individual enzyme molecule dimensions were changed after interacting with quantum dot. Consequently, this result could be helpful for constructing safe and effective utilisation of QDs in biological applications.
authors: School of Chemistry, Bharathidasan University, Tiruchirappalli, 620 024, India.|Department of Chemistry, Sri G. V. G Visalakshi College for Women, Udumalpet, 642 128.
authors: Vaishnavi
authors: V
authors: Ellappan
authors: School of Chemistry, Bharathidasan University, Tiruchirappalli, 620 024, India.
authors: Manibalan
authors: M
authors: Kesavan
authors: Centre for Nanoscience and Nanotechnology, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu, India.
authors: Parameshwari
authors: P
authors: Ramalingam
authors: Centre for Nanoscience and Nanotechnology, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu, India.
authors: Jeganathan
authors: J
authors: Kulandaivel
authors: School of Chemistry, Bharathidasan University, Tiruchirappalli, 620 024, India.
authors: Renganathan
authors: R
authors: Rajalingam
mesh_terms: D002918:Chymotrypsin / Q000737:chemistry* / Q000378:metabolism; D002942:Circular Dichroism; D008027:Light; D045663:Quantum Dots; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002918:Chymotrypsin; C117608:alpha-chymotrypsin
keywords: MPA-CdTe quantum dots; atomic force microscopy; chymotrypsin; circular dichroism