The invention provides methods to detect molecular recognition events. The invention also provides methods to detect the presence of or identify a target species based on its interaction with one or more probe species. The methods of the invention are based on amplification of the signal due to each molecular recognition event. The amplification is achieved through photopolymerization, with the polymer formed being associated with the molecular recognition event. In one aspect, a fluorescent polymer, a magnetic polymer, a radioactive polymer or an electrically conducting polymer can form the basis of detection and amplification. In another aspect, a polymer gel swollen with a fluorescent solution, a magnetic solution, a radioactive solution or an electrically conducting solution can form the basis of detection and amplification. In another aspect, detectable particles can be included in the polymer formed. In another aspect, sufficient polymer forms to be detectable by visual inspection.