Nanostructured MoS 2 ‑Based Advanced Biosensors: A Review Shaswat Barua, †,‡ Hemant Sankar Dutta, † Satyabrat Gogoi, † Rashmita Devi, † and Raju Khan* ,† † Analytical Chemistry Group, Chemical Sciences & Technology Division, Academy of Scientific and Innovative Research, CSIR-North East Institute of Science & Technology, Jorhat 785006, Assam, India ‡ Department of Chemistry, School of Basic Sciences, Assam Kaziranga University, Koraikhowa, NH-7, Jorhat 785006, Assam, India ABSTRACT: The introduction of nanotechnology in biosensor applications has significantly contributed to human lifestyle by rendering advanced personalized diagnostics and health care and monitoring equipment and techniques. Nanomaterials and nanostructures have recently gained impetus in the domain of biosensors because of their manifold applications. Transition-metal dichalcogenides (TMDs) newly attracted interest because of their multidimensional structures and structure-dependent unique electronic, electrocatalytic, and optical properties, which can be explored to design novel biosensing platforms. The content of the present article aspires to advocate a critical evaluation on the recent advances in the domain of dimensionally different MoS 2 , the most widely explored TMD, and their relevance in biosensing application. This encompasses the major structural attributes and synthetic methodologies of zero-, one-, two-, and three- dimensional MoS 2 nanostructures, pertaining to their biosensing potential. Herein, we described the prevailing and potential applications of MoS 2 nanostructures in optical, electrochemical, and electronic biosensors. KEYWORDS: MoS 2 , advanced biosensor, nanostructures, optical, electrochemical 1. INTRODUCTION Human well-being is greatly dependent on the ease of lifestyle, which often loses its pace due to serious health issues. This raises the importance of modern tools and techniques to detect and diagnose various diseases or allied factors regularly as precautionary measures. The development of biosensors has contributed a significant share in this regard. Biosensing implies the use of some basic tools and techniques to detect disease factors easily and selectively. 1 This selectivity ascertains the possibility of using such biosensors in clinical real-time sample monitoring. 2 Another important parameter, sensitivity dictates the quality of a biosensor. 3 A great deal of research has been involved in attaining the desired selectivity and sensitivity by tailoring the sensor matrices. 4-6 The development of nanotechnology has diverted the attention of the scientific community from conventional sensing techniques and resulted in the fabrication of highly selective biosensors with nanomolar-level capacity of sensing bioanalytes. 5 Molybdenum disulfide (MoS 2 )-based nanomateri- als have attained the utmost attention in recent times because of their manifold advantageous attributes. 7 MoS 2 comprises S- Mo-S triple layers with well-known semiconducting properties of metal dichalcogenide compounds. 8 Excellent electrochemical attributes and luminescence properties have endorsed MoS 2 - based nanomaterials as novel biosensing probes for the careful detection of a range of analytes. 9 Their multidimensional structures are the prime cause of attraction with their multifaceted application potentials. In broader aspects, nanomaterials can be categorized as zero- (0D), one- (1D), two- (2D), and three-dimensional (3D) structures. The synthesis and applications of MoS 2 with different dimensions have been well documented in the literature. Variation of the precursors, synthetic materials, and methodologies mainly dictates the shape and size of the MoS 2 nanostructures. 10-12 Each dimension has a unique attribute that renders tremendous potential for biosensing applications. 0D MoS 2 quantum dots, also referred to as “inorganic fullerenes”, are nanooctahedral structures with size <10 nm. 13-15 Because of similar structural attributes with fullerene, MoS 2 dots also exhibit excellent electronic and catalytic activity. Further, 1D MoS 2 quantum dots show strong photo- luminescence at specific excitation wavelengths due to a quantum confinement effect that enables optical biosensing of a range of analytes with a simple fluorimetric technique. 16 Presently, MoS 2 nanoprobes have been studied extensively for efficient fluorimetric detection of a range of bioanalytes. 17,18 2D MoS 2 nanostructures have been explored for electro- chemical biosensing because of their tunable electronic energy states. 8 The state of literature cites promising aspects of MoS 2 sheets as electrode materials in amperometric and impedance- based biosensors. 19,20 The graphene-like structure of MoS 2 has opened newer avenues for research in the domain of biosensors and devices. MoS 2 nanosheets of this dimension exhibit a direct Received: November 7, 2017 Accepted: December 22, 2017 Published: December 22, 2017 Review www.acsanm.org Cite This: ACS Appl. Nano Mater. 2018, 1, 2-25 © 2017 American Chemical Society 2 DOI: 10.1021/acsanm.7b00157 ACS Appl. Nano Mater. 2018, 1, 2-25 This article is made available for a limited time sponsored by ACS under the ACS Free to Read License, which permits copying and redistribution of the article for non-commercial scholarly purposes. Downloaded via 192.126.168.233 on November 2, 2018 at 20:34:23 (UTC). See https://pubs.acs.org/sharingguidelines for options on how to legitimately share published articles.