Review Article Adv. Mat. Lett. 2014, 5(11), 612-628 ADVANCED MATERIALS Letters Adv. Mat. Lett. 2014, 5(11), 612-628 Copyright © 2014 VBRI press www.amlett.com, www.vbripress.com/aml, DOI: 10.5185/amlett.2014.4562 Published online by the VBRI press in 2014 A review on CdSe quantum dots in sensing Pragati Malik, Jyoti Singh, Rita Kakkar * Computational Chemistry Laboratory, University of Delhi, Delhi 110 007, India * Corresponding author. Tel: (+91) 11 27666313; E-mail: rkakkar@chemistry.du.ac.in Received: 01 April 2014, Revised: 30 June 2014 and Accepted: 30 June 2014 ABSTRACT The primary aim of this review is to survey the literature on the ion sensing ability of quantum dots. Sensing of both cations and anions is important, since both play significant roles in various ecological and biological processes, which makes it important to ensure their concentration at balanced level. Contamination by heavy metal ions and various anions poses a serious threat to humans, aquatic organisms, and to the environment; therefore detection of these ions (in presence of other cations and anions), which are the major cause of environmental pollution is of immense significance at the present time. Owing to their enhanced fluorescence properties and photostability, QDs offer tremendous scope to be used for ion sensing. They offer several advantages over traditional chemical fluorophores. This review throws light on the mechanism adopted by CdSe QDs to act as flourophores. Owing to their enhanced photoluminescence properties, QDs offer selective and sensitive determination of various ions, which is a function of the capping on the surface of the QD nanosensor, i.e. it is possible to tune their sensing ability by changing the capping layer, which influences the QD's interaction with various analytes. Hence, these quantum dots may prove promising candidates in future for sensing approximately all types of analytes. Copyright © 2014 VBRI press. Keywords: Core/shell quantum dots; analyte detection; luminescence; fluorescence; fluorophore; metal ions sensing; photoluminescence; quantum dots quenching; nanonanosensors. Pragati Malik has done her B.Sc. (2007) and M.Sc. (2009) in Physical Chemistry (specialization) from Delhi University, India and has completed her Ph.D. under supervision of Prof. Rita Kakkar from University of Delhi in 2013. Her research interests include theoretical studies of nanomaterials, particularly CdSe quantum dots and their interaction with various chemical and bio- analytes in order to develop novel chemical and biosensors. Jyoti Singh is currently working as an Assistant Professor in Department of Chemistry at Hans Raj College, University of Delhi (India). She has been teaching Physical Chemistry for the past three years. She has completed her Ph.D. under Prof. Rita Kakkar from University of Delhi, India in 2010. Her research interest includes computational studies of quantum dots, their properties especially their magnetism and their applications. Rita Kakkar, after obtaining a PhD degree in Physical Chemistry from the University of Delhi, undertook research on various topics. She has been teaching Physical Chemistry at the University of Delhi for the past three decades. Prior to that, she taught at Miranda House, University of Delhi. In the field of chemistry education, she is actively involved in designing syllabi of various universities and conducting teacher-training workshops, and for popularizing the use of Molecular Modelling in teaching chemistry. Her main research interests are in Computational Chemistry and related fields. She heads a large research group, which is carrying out computational and experimental studies on catalysis by nanomaterials and by enzymes. The focus of the research on nanomaterials is to understand the growth, morphologies and stabilities of nanocrystalline forms of metals and metal oxides, their reactivities, and their catalytic role in various reactions, particularly those involving degradation of organic pollutants. Her research on nanoscale materials also includes theoretical and experimental studies on quantum dots and their size-dependent properties for use as semiconductor devices and sensors. Professor Rita Kakkar has over 95 research publications in international journals. She has successfully supervised the work of 35 PhD and 7 MPhil students. She has delivered invited several talks at scientific conferences. She also regularly reviews manuscripts for many international journals, including those published by the American Chemical Society, Royal Society of Chemistry, Wiley and Elsevier.