TY - JOUR
T1 - CMC determination using isothermal titration calorimetry for five industrially significant non-ionic surfactants
AU - Smith, Oliver
AU - Waters, Laura
AU - Small, William
AU - Mellor, Steve
N1 - Funding Information:
We wish to thank Croda Europe Ltd. for their financial support of this work.
Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/3/1
Y1 - 2022/3/1
N2 - Surfactants are used in a vast array of products including pharmaceuticals, cosmetics and household formulations. From an industrial perspective, non-ionic surfactants are ideal for inclusion within such products as they are non-toxic, simple to formulate and economic to use. This study considers five non-ionic surfactants (Tween 20, Tween 80, Crodasol, Croduret and Etocas 35) to determine the critical micellar concentration (CMC) for each using isothermal titration calorimetry, thus avoiding issues regarding poor accuracy found with other techniques. Furthermore, this methodology has not previously been applied to this group of surfactants. For the most commonly used non-ionics (Tween 20 and Tween 80) a further study was undertaken to consider the influence of surfactant purity on the CMC determined, using standard grade (Tween 20 and 80), high purity (Tween 20 HP and Tween 80 HP) and Super Refined (SR PS20 and SR PS80). Results permitted calculation of the CMC for the surfactants whereupon the values were determined to range from 1.0 mM for Tween 20 HP to 2.9 mM for Tween 80 HP. Such information regarding the CMC event is useful from a formulation perspective as it can ensure that the most optimum concentration of surfactant is included within a formulation to maximize its efficacy.
AB - Surfactants are used in a vast array of products including pharmaceuticals, cosmetics and household formulations. From an industrial perspective, non-ionic surfactants are ideal for inclusion within such products as they are non-toxic, simple to formulate and economic to use. This study considers five non-ionic surfactants (Tween 20, Tween 80, Crodasol, Croduret and Etocas 35) to determine the critical micellar concentration (CMC) for each using isothermal titration calorimetry, thus avoiding issues regarding poor accuracy found with other techniques. Furthermore, this methodology has not previously been applied to this group of surfactants. For the most commonly used non-ionics (Tween 20 and Tween 80) a further study was undertaken to consider the influence of surfactant purity on the CMC determined, using standard grade (Tween 20 and 80), high purity (Tween 20 HP and Tween 80 HP) and Super Refined (SR PS20 and SR PS80). Results permitted calculation of the CMC for the surfactants whereupon the values were determined to range from 1.0 mM for Tween 20 HP to 2.9 mM for Tween 80 HP. Such information regarding the CMC event is useful from a formulation perspective as it can ensure that the most optimum concentration of surfactant is included within a formulation to maximize its efficacy.
KW - Calorimetry
KW - CMC
KW - ITC
KW - non-ionic; surfactants
KW - Surfactants
KW - Non-ionic
UR - http://www.scopus.com/inward/record.url?scp=85122811531&partnerID=8YFLogxK
U2 - 10.1016/j.colsurfb.2022.112320
DO - 10.1016/j.colsurfb.2022.112320
M3 - Article
C2 - 35042120
AN - SCOPUS:85122811531
VL - 211
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
SN - 0927-7765
M1 - 112320
ER -