This invention relates to a composition and its use for formulating nucleic acid-based drugs/vaccines with sugar alcohol compositions into complexes for both in-vitro and in-vivo delivery. Particularly, the present invention includes the ingredients and processes necessary for formulating therapeutic and pharmaceutical nucleic acid compositions, such as miRNA, microRNA precursors, shRNAs, siRNAs, ribozymes, antisense RNAs/DNAs, RNA-DNA hybrids and DNA vectors/vaccines, with glycylated sugar alcohols/sugars into delivery complexes, which can then be absorbed by cells in vivo and in vitro via active endocytosis. Also, the present invention discloses that chemical compounds containing sugar alcohol- and/or sugar-like structures can protect nucleic acids, in particular miRNAs, shRNAs, siRNAs and ribozymes, from degradation in vivo as well as in vitro. Therefore, the present invention is also a formula and method for preserving the structural integrity and functional efficacy of these nucleic acid-based drugs and/or vaccines in vivo and in vitro.