Methods, compositions and kits for capturing, detecting and quantifying mature small RNAs are provided herein. Embodiments of the methods comprise ligating 5′ and 3′ ligation adaptors to the 5′ and 3′ ends of the mature small RNAs, respectively, in the presence of 5′ and 3′ semi-degenerate ligation splints to generate a ligation product. Other embodiments comprise reverse transcribing polyadenylated mature small RNA with a universal reverse transcription primer and ligating an adaptor to the 3′ end of the cDNA in the presence of a semi-degenerate ligation splint to generate a cDNA ligation product.