使用html2pdf防止文本在<sub> </ sub>标记周围的新行上中断

I am using spipu/html2pdf PDF creation library in order to render some text on an A4 page.

The text is wrapped in

tag and goes something like this:

 <p>Chemical corrosion is one of the ways to break down a substrate. 
C<sub>2</sub>SO<sub>4</sub> is one of the strongest suited for this 
 purpose. 

Somtimes the part with C<sub>2</sub>SO<sub>4</sub> will be a the end of the line in which case it will break on a new line along the tags and this is something that I would like to prevent.

I have tried wrapping it in an element on it's own and setting white-space: nowrap; on it but it does not seem to have any effect.

The library has partial support for up to css 2.1.

Thank you for your help.