In chapter one, literature review have been down about the photophysical properties of lanthanide complexes and their applications. In chapter 2, the design and synthesis of water soluble cyclen based europium complexes with cyclin A specific peptides were described. Linear and two-photon induced hypersensitive europium emission gave the real time signalling and also enhanced the two-photon induced emission from 12GM to 68GM after Cyclin A binding. In chapter 3, the design of water soluble multi-modal porphyrin based compounds for key cell cycle regulator- Plk 1 imaging and cancer cells inhibition were described. Two water soluble porphyrin compounds have been synthesized and shown the specific photodynamic therapy treatment in the cancer cells via the selectively binding with Polo-like kinase 1 (Plk1). Plk1 is responsible for cell cycle regulation. Commercial or known Plk1 inhibitor/bioprobes are always poor cell internalization and easily to be damaged by enzymatic degradation. In addition, these markers are not available to image and inhibit the Plk1 as dual function probe. We introduced a new approach amphiphilic porphyrin with Plk1 specific peptide. Our compounds shown responsive emission enhancement upon binding with Plk1 in aqueous medium. In vitro, it can triggered G2-M phase arrest and inhibited the cancer cells specific as Plk1 is overexpressed in cancer cell. In chapter 4, we designed and synthesized a platinumeuropium complex (PtEuL401) as a controlled delivery vehicle of cisplatin. PtEuL401 shown responsive emission with the appropriate light excitation in aqueous and in vivo during the drug delivery process. Compared with the existing prodrugs, we offer real-time monitoring of the therapy process. Also, the long emission lifetimes of lanthanides creates room for further development in time-resolved imaging protocols which eliminates the problem of autofluorescence.