In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The nephroprotective effect of coenzyme Q10 was investigated in mice with acute renal injury induced by a single i . p . injection of cisplatin ( 5 mg / kg ) .
### Output Text:
The nephroprotective effect of <span class="chemical">coenzyme Q10</span> was investigated in mice with acute renal injury induced by a single i . p . injection of <span class="chemical">cisplatin</span> ( 5 mg / kg ) . 