Recent progress in the sensing techniques for the detection of human thyroid stimulating hormone

Thyroid-stimulating hormone (TSH) protein in the human serum is considered as a most sensitive indicator for the diagnosis of several diseases related to hyperthyroidism and hypothyroidism. Hypothyroidism due to high TSH levels cause pituitary tumors, congenital hypothyroidism in infants and chronic lymphatic thyroiditis, whereas hyperthyroidism caused by low TSH levels lead to rapid and irregular heartbeat, disorders in eyes (Grave's ophthalmopathy) and Plummer's disease. Therefore, a timely and sensitive detection of TSH is very important for early intervention and prevention of thyroid related diseases. This review article delineates the theoretical background and recent developments of various methods that have been so far proposed in the literature to detect TSH along with their respective merits and demerits. In this article, the selective works on the TSH biosensors have been reviewed by highlighting the transduction mechanism and the sensing performance together with the future perspective for further advancement and commercialization of TSH biosensors.