What will be the regex for a word ending with alphabet?

e.g. 

> 
> xyz,121%^&%^asasa  
> 
>  1212asas  
> 
>  ^%^asffa
> 
> 
> 

should be allowed. But words like 

> 
> asa1212  
> 
>  @#fdf1212  
> 
>  121sdsd123
> 
> 
> 

shouldn't be allowed.