SOL3D: Soft-lithography on 3D vat polymerised moulds for fast, versatile, and accessible high-resolution fabrication of customised multiscale cell culture devices with complex designs

Abstract

Commercially available cell culture devices are designed to increase the complexity of simple cell culture models to provide better experimental platforms for biological systems. From microtopography, microwells, plating devices and microfluidic systems to larger constructs for specific applications like live imaging chamber slides, a wide variety of culture devices with different geometries have become indispensable in biology labs. However, the techniques used for their fabrication can be out of reach for most wet labs due to cost and availability of specialised equipment or the need for engineering expertise. Moreover, these techniques also have technical limitations to the volumes, shapes and dimensions they can generate. For these reasons, creating customisable devices tailored to lab-specific biological questions remains difficult to apply. Taking advantage of low-cost, high-resolution desktop resin 3D printers combined with PDMS soft-lithography we have developed an optimised microfabrication pipeline capable of generating a wide variety of customisable devices for cell culture and tissue engineering in an easy, fast reproducible way for a fraction of the cost of conventional microfabrication or commercial alternatives. This technique enables the manufacture of complex devices across scales bridging the gap between microfabrication and fused deposition moulding (FDM) printing. The method we describe allows for the efficient treatment of resin-based 3D printed constructs for PDMS curing, using a combination of curing steps, washes and surface treatments. Together with the extensive characterisation of the fabrication pipeline, we provide several proof-of-principle applications ranging from simple 2D culture devices to large tissue engineering constructs and organoid formation systems. We believe this methodology will be applicable in any wet lab, irrespective of prior expertise or resource availability and will therefore enable a wide adoption of tailored microfabricated devices across many fields of biology.

Machine Learning‐Assisted High‐Throughput SERS Classification of Cell Secretomes

“…In addition, thanks to the implementation of a microfabrication protocol that integrates 3D stereolithography (SLA) printing and PDMS soft lithography (see Experimental Section), [ 32 ] we could generate a wide variety of microfluidic chips, tailored to our specific requirements of cell culture and SERS substrate formation. A high‐throughput device was devised (Figure 5e) with 10 circular wells that enabled cell seeding and adequate flow, induced by external capillary pumps (see Figure S9, Supporting Information, for the 3D printed mold).…”

“…Subsequently, 3D printed resinbased masters were cleaned using 2-propanol and cured by a 365 nm UV light. After that, the resin was covered with a thin layer of enamel to improve PDMS curation process, as reported in Hagemann et al [32] Polydimethylsiloxane was mixed at a 10:1 weight ratio of base to curing agent. The mixed solution was poured into the resin master and then degassed to remove air bubbles.…”

BDNF controls phosphorylation and transcriptional networks governing cytoskeleton organization and axonal regeneration

“…A two-part system was used for axonal isolation from cell bodies without physical barrier, consisting of microgrooves and a plating device 30 . The first part was a PDMS-based micro groove substrate (10um x10um width/height; Sylgard 184, Dow Corning).…”

“…The prepared substrates were used up to 1 week after manufacturing. The plating device was manufactured using 3D vat polymerised printed molds 30 Molds were printed at 50 um z-resolution on a Phrozen Mini 4k using 4k-Aqua Grey resin (Phrozen). Afterwards, the molds were washed and sonicated in isopropanol and then UV cured (Wash & cure, Anycubic) for 1h.…”

“…We next compared the somatic and axonal activation of ERK1/2 and AKT in response to BDNF in motor neurons. For this comparison we cultured the i 3 LMNs on a microfabricated culturing platform combining soft lithography and 3D printed molds (SOL3D) 30 , which has been developed specifically to study axonal biology 31 (Fig. 1I).…”