Colin L Raston,a* Nikita Joseph,a and Michael Z Michaelb 

a College of Science and Engineering, Flinders University, Bedford Park, SA Australia
b College of Medicine and Public Health, Flinders University, Bedford Park, SA Australia


The recently developed vortex fluidic device (VFD) has complex fluid dynamics with high shear rates which can be harnessed for a broad range of applications – materials processing, probing the structure of self organized systems, and controlling chemical reactivity and selelctivity.1,2 Under continuous flow, liquids are delivered to the base or to pre-determined points along the inside of the rapidly rotating tube, 2k – 10k rpm (10 or 20 mm OD quartz or borosilicate glass), which is titled with  45o as  the usual optimal angle for a number of applications. The VFD is effective in preparing aerogels with antimicrobial activity, protein folding, enhancing enzymatic reactions,3 loading drugs in targeted delivery vehicles (Fig. 1), and many more applications.4 More recently we have established that it is effective in preparing liposomes under scalable continuous flow conditions. A single VFD microfluidic platform can process ca 1 mL/min of highly concentrated phospholipid solution, generating liposomes with a uniform size distribution, without the need for further processing, and avoiding time consuming membrane extrusion. 

According to Drug Delivery Systems (DDS) & Enhanced Permeability Retention (EPR) the ideal size for liposomes is from 100 to 200 nm. Fabricating liposomes using traditional batch processing usually involves a number of steps. Conventional channel based microfluidics can be used to fabricate liposomes but they suffer from limited scalability and potential clogging. The controlled mechano-energy in the VFD allows access to liposomes under continuous flow with control over size (ca 100 - 200 nm) and polydispersity from 0.2 – 0.3, with the ability to prepare GUV of 600 nm liposomes by systematically varying the control parameters of the microfluidic thin film platform. Moreover the shear stress in the VFD can also be used to load the liposomes with drug molecules in-situ continuous flow, and the liposomes can be rendered fluorescent by incorporating 1% fluorophore tagged phospholipid.   

1 Yasmin, L; X. Chen, X; Stubbs, KA; Raston, CL Scientific Reports, 2013, 3, 2282 Optimising a vortex fluidic device for controlling chemical reactivity and selectivity. 
2 Britton, J; Stubbs, KA; Weiss, GA; Raston, CL Chem. Eur. J. 2017 DOI: 10.1002/chem.201700888 Vortex Fluidic Control of Chemical Transformations.
3 Britton,J; Meneghini, LM; Raston CL; Weiss GA Angew. Chem. Int Ed., 2016, 55, 11387-11391. Accelerating Enzymatic Catalysis Using Vortex Fluidics.
4 Mo, J.; Eggers, PK; Chen, X; Ahamed, MRH; Becker, T; Lim,  LY; Raston, CL Scientific Reports, 2015, 5:10414 Shear induced carboplatin binding within the cavity of a phospholipid mimic for increased anticancer efficacy.

Biographic Details
Colin Raston AO
Professor in Clean Technology
Flinder University, SA Australia 
Phone: +61439709950 E-mail:
Research interests: Nanomaterials, Drug Delivery, Liposomes