Automated multistep organic synthesizer based on organic solvent nanofiltration: OSN-Syn

Abstract

OSN-Syn Platform The OSN-Syn platform is a modular, fully automated system for multistep organic synthesis and organic solvent nanofiltration (OSN) purification. It is constructed from robust, low-cost, off-the-shelf components, including an XYZ-gantry-mounted gripper, a syringe-pump-driven solvent dispenser, a robotic pipette, a nitrogen blower for gentle solvent evaporation, a thermostated heating/stirring plate, an in-line filtration unit, and a pneumatic clamp. The core of the platform is a custom-designed automated OSN purification cell that enables seamless integration of synthesis and purification. The gripper, dispenser, and pipette share a common XYZ motion stage, allowing precise transfer of vessels, columns, and liquids among modules. All components are housed within an inert-gas glovebox, enabling fully automated air- and moisture-sensitive reactions. Each physical manipulation—such as open cap, transfer solution, or OSN purification—is abstracted into one of 13 unit commands that replicate standard manual operations. Because the command set mirrors bench-scale practice, a conventional experimental procedure can be directly converted into a digital chemical recipe file (CRF) by concatenating these commands within the human-machine interface (HMI). System control is governed by a Programmable Logic Controller (PLC) implemented in IEC 61131-3 Structured Text (CODESYS-compatible dialect) using Inovance InoProShop V1.8.1.3. An Inovance AM521 controller provides millisecond-scale deterministic control and real-time sensor feedback from reaction setup through intermediate purification. Peripheral devices communicate via a hybrid industrial network incorporating RS-232, RS-485, Ethernet, Modbus TCP/IP, and EtherCAT protocols. Pneumatic actuators—including cylinders, gas lines, and valves—are driven by an AirTAC 6D-series solenoid valve manifold (6D1H14F-J06BS5P5C1CEA1) over EtherCAT. Magnetic reed proximity sensors track cylinder end positions, with sensor states aggregated through an I/O concentrator for PLC integration. The HMI was developed using EasyBuilder Pro V6.10.01.259s, providing real-time visualization, simulation, and direct PLC interfacing for local process control. Remote monitoring and operation are enabled through ToDesk, a secure cross-platform remote-access solution supporting mobile device control under stable network conditions.