Provided are methods for non-enzymatically synthesizing nucleic acids. The methods include submerging a first portion of the outer surface of a cylinder in a non-enzymatic nucleic acid synthesis reaction mixture. The reaction mixture has a pH of 4 or less and includes an organizing matrix reagent and monophosphate nucleotides. The methods further include rotating the cylinder about its axis of radial symmetry so that the first portion of the outer surface of the cylinder is no longer submerged in the reaction mixture, thereby providing a thin film of the reaction mixture on the first portion of the outer surface of the cylinder. The methods further include heating and drying the thin film to form phosphodiester bonds between the monophosphate nucleotides of the thin film. Also provided are devices that find use, e.g., in practicing the methods of the present disclosure.

Multi-stage sample-recovery systems, including automated 2-stage and 3-stage sample-recovery systems, are provided. Such systems enable the rapid screening and recovery of samples, including viable cell-based samples, from high-throughput screening systems, including systems utilizing large-scale arrays of microcapillaries. In specific screening systems, each microcapillary comprises a solution containing a variant protein, an immobilized target molecule, and a reporter element. Immobilized target molecules may include any molecule of interest, including proteins, nucleic acids, carbohydrates, and other biomolecules. The association of a variant protein with a molecular target is assessed by measuring a signal from the reporter element. The contents of microcapillaries identified in the assays as containing variant proteins of interest can be identified and recovered using the multi-stage systems disclosed herein.

Provided are methods for non-enzymatically synthesizing nucleic acids. The methods include submerging a first portion of the outer surface of a cylinder in a non-enzymatic nucleic acid synthesis reaction mixture. The reaction mixture has a pH of 4 or less and includes an organizing matrix reagent and monophosphate nucleotides. The methods further include rotating the cylinder about its axis of radial symmetry so that the first portion of the outer surface of the cylinder is no longer submerged in the reaction mixture, thereby providing a thin film of the reaction mixture on the first portion of the outer surface of the cylinder. The methods further include heating and drying the thin film to form phosphodiester bonds between the monophosphate nucleotides of the thin film. Also provided are devices that find use, e.g., in practicing the methods of the present disclosure.