How to create regexp pattern from constants and variables?

import (
    "fmt"
    "regexp"
)

const (
    NBSP            = "xA0"
    NBSP_UTF8       = "xC2xA0"
    NBSP_UTF16      = "x00xA0"
)

func main(){
    var re = regexp.MustCompile(NBSP_UTF16+"|"+NBSP_UTF8+"|"+NBSP)
    fmt.Println(re)
}

Here I want to create a pattern that match all occurrences of 3 different variants of non-breaking spaces and replace them with a normal space

panic: regexp: Compile("x00xa0|u00a0|xa0"): error parsing regexp: invalid UTF-8: `▒| |▒` [recovered]