Centripetal force in vector form can be expressed as
$\overrightarrow{F} = \dfrac{mv^2}{r}$
$\overrightarrow{F} = \dfrac{mv^2}{r}\overrightarrow{r}$
$\overrightarrow{F} = mv^2\overrightarrow{r}$
$\overrightarrow{F} = –\dfrac{mv^2}{\overrightarrow{r}}\overrightarrow{r}$