Imperial College London
Portrait Picture

ProfessorJoaoCabral

Faculty of Engineering, Department of Chemical Engineering

Professor of Soft Matter
 
 
 
//

Contact

 

+44 (0)20 7594 5571j.cabral Website

 
 
//

Assistant

 

Mrs Sarah Payne +44 (0)20 7594 5567

 
//

Location

 

517AACE ExtensionSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Wang:2020:10.1063/1.5144770,
author = {Wang, H and Khodaparast, S and Carroll, J and Kelly, C and Robles, ESJ and Cabral, JT},
doi = {10.1063/1.5144770},
journal = {Review of Scientific Instruments},
pages = {1--11},
title = {A microfluidic-multiwell platform for rapid phase mapping of surfactant solutions},
url = {http://dx.doi.org/10.1063/1.5144770},
volume = {91},
year = {2020}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Measurement of the phase behavior and (meta)stability of liquid formulations, including surfactant solutions, is required for the understanding of mixture thermodynamics, as well as their practical utilization. We report a microfluidic platform with a stepped temperature profile, imposed by a dual Peltier module, connected to an automated multiwell plate injector and optical setup, for rapid solution phase mapping. The measurement protocol is defined by the temperature step ΔT ≡ T1 − T2 (100 °C), volumetric flow rate Q ≡ ΔV/Δt (50 μl/min), which implicitly set the thermal gradient ΔT/Δt (0.1–50 °C/min), and measurement time (which must exceed the intrinsic timescale of the relevant phase transformation). Furthermore, U-shaped microchannels can assess the reversibility of such transformations, yielding a facile measurement of the metastable zone width of the phase diagram. By contrast with traditional approaches, the platform precisely controls the cooling and heating rates by tuning the flow rate, and the absolute temperature excursion by the hot and cold thermal profile, which remain stationary during operation, thus allowing the sequential and reproducible screening of large sample arrays. As a model system, we examined the transition from the micellar (L1) to the liquid crystalline lamellar phase (Lα), upon cooling, of aqueous solutions of sodium linear alkylbenzene sulfonate, a biodegradable anionic surfactant extensively employed in industry. Our findings are validated with quiescent optical microscopy and small angle neutron scattering data.
AU  - Wang,H
AU  - Khodaparast,S
AU  - Carroll,J
AU  - Kelly,C
AU  - Robles,ESJ
AU  - Cabral,JT
DO  - 10.1063/1.5144770
EP  - 11
PY  - 2020///
SN  - 0034-6748
SP  - 1
TI  - A microfluidic-multiwell platform for rapid phase mapping of surfactant solutions
T2  - Review of Scientific Instruments
UR  - http://dx.doi.org/10.1063/1.5144770
UR  - https://aip.scitation.org/doi/10.1063/1.5144770
UR  - http://hdl.handle.net/10044/1/78030
VL  - 91
ER  -
Download