Can I Use Paypal REST API in Titanium?

I want to use the Paypal REST API in my titanium app, I write code like this :

function paypal(){
    var data = {grant_type: 'client_credentials'};
    var xhr = Titanium.Network.createHTTPClient({
        onload: function() {
            alert(this.responseText);
        },
        onerror: function(e) {
            alert(e.error);
        },
        timeout : 5000
    });
    xhr.open('POST', 'https://clientID:secret@api.sandbox.paypal.com/v1/oauth2/token');
    xhr.setRequestHeader('Accept','application/json');
    xhr.setRequestHeader('Accept-Language','en_us');
    xhr.send(data);
}