Problem with RegularExpression in Data annotations

Hi, I'm doing a form and validating with data annotations but I need my user to have no intermediate spaces the problem is that my regulation is not working, could you help me find a solution please.

Here is my expression.

    [Display(Name = "Usuario")]
    [Required(ErrorMessage = "El campo {0} es requerido.")]
    [RegularExpression(@"[\s], ErrorMessage = "El campo {0} no puede tener espacio en blanco")]
    [MaxLength(30, ErrorMessage = "El campo {0} solo puede contener un máximo de {1} caracteres de longitud.")]
    public string UsuarioRLogin { get; set; }