Identifying the interactions of small molecules with biomolecules in complex cellular environments is a significant challenge. As one important example, despite being widely used for decades, much is still not understood regarding the cellular targets of Pt(II)-based anticancer drugs. In this study we introduce a novel method for isolation of Pt(II)-bound biomolecules using a DNA hybridization pull-down approach. Using a modified Pt reagent, click-ligation of a DNA oligonucleotide to both a Pt(II)-bound DNA hairpin and bovine serum albumin (BSA) are demonstrated. Subsequent hybridization to a biotin-labeled oligonucleotide allows for efficient isolation of Pt(II)-bound species by streptavidin pulldown. We also find that platinated bovine serum albumin readily crosslinks to DNA in the absence of click ligation, and that a fraction of BSA-bound Pt(II) can transfer to DNA over time. Interestingly, in in vitro studies, fragmented mammalian DNA that is crosslinked to BSA through Pt(II) exhibits significantly increased protection from degradation by serum nucleases. This work presents a novel click-based method to enrich Pt(II)-bound biomolecules. Pt(II)-bound DNA and proteins are readily isolated using an oligonucleotide hybridization strategy. Interestingly, Pt(II)-dependent and click-independent crosslinking of a DNA oligonucleotide to serum albumin was observed, and DNA crosslinked to protein is dramatically protected from serum nucleases. Display omitted •New method for isolating Pt-bound biomolecules by DNA click-ligation and hybridization•Successful click-ligation of DNA to Pt-bound biomolecules•Surprising DNA-protein crosslinking with non-click Pt(II) reagents•Some Pt(II) transfer from protein to DNA•Significant increase in serum half-life for DNA crosslinked to proteins