MATLAB: How to find character bigrams from a string

bigramstext;

Hello, I would like to find all character bigrams from a string sentence. For example night -> {ni,ig,gh,ht}. Is there a Matlab code?

Thank you very much

 str  = 'night';
 list = cellstr([str(1:end-1); str(2:end)].')

EDIT

Do you want?

string = 'ab bc cd ef gh ij kl'
regexp(string,'\s+','split');

userid = char(bin2dec(reshape(watermark(1:160),[],8))).'
passwrd = char(bin2dec(reshape(watermark(161:320),[],8))).'
str = [userid passwrd]