Nicotinic acetylcholine receptors (nAChRs) belong to the superfamily of ligand-gated ion channels and are distributed widely in the human and nonhuman brain. Several nAChRs have been identified and characterized pharmacologically and have distinct patterns of distribution in the brain. The nicotine alpha 4 beta 2 receptor subtypes are thought to play a role in various diseases, including various brain disorders (e.g., Alzheimer's disease), behavioral disorders (e.g., schizophrenia or substance abuse), various neoplasms (e.g., lung cancer), and other diseases, and may also be involved in the addiction to nicotine in chronic tobacco users (tobacco use may increase the number of the alpha 4 beta 2 receptor sites). The development of noninvasive imaging methods using PET and SPECT of the alpha 4 beta 2 receptor system has gained significant interest. Therefore, and not surprisingly, the development of noninvasive imaging methods using PET and SPECT of the alpha 4 beta 2 receptor system has gained significant interest. However, current radiotracers suffer from several drawbacks, including rapid clearance, toxicity, and undesirable kinetic parameters. Consequently, there is still a need to provide improved compositions and methods for radioligands for receptors of the alpha 4 beta 2 receptor type.