Zeta potential changing nanoemulsions based on phosphate moiety cleavage of a PEGylated surfactant

Alkaline Phosphatase: A Reliable Endogenous Partner for Drug Delivery and Diagnostics

“…Phosphatase inhibitors are often used in various in vitro studies especially on cultured cell models and on freshly excised tissue to evaluate the impact of ALP on the performance of phosphate functionalized DDS. [7,81,103,104] Performing cellular uptake studies of phosphorylated NCs with and without inhibition of ALP, for instance, can show the effect of this enzyme on the performance of these delivery systems as depicted in Figure 4. Table 2 lists some common inhibitors and activators of various isotypes of ALP as well as their proposed mechanism.…”

“…In order to eliminate the toxic effects derived from tertiary amine structure of POAP, Kurpiers et al used polyoxyethylene ( 9) nonylphenol monophosphate ester (PNPP) as phosphorylated surfactant and upon incubation with bovine intestinal ALP within 4 h 92% of total phosphate was cleaved off which is almost twofold higher than POAP. [104] Apart from the formulation-related factors for this enhancement, structure differences of the surfactants are playing an important role. Due to double-chain structure of POAP, a steric hindrance might take place leading to an increased phosphate release in the case of PNPP having a single PEG chain (Table 4).…”

“…This corona effect was shown by Zaichik et al, as in the absence of PEGylated emulsifiers zeta potential changes of Δ40 mV upon contact with ALP were measured whereas nanoemulsions containing polyethoxylated-35 castor oil remained constant without any significant change in zeta potential due to the hindrance of PA. [213] Furthermore, a significant amount of phosphate was released from DOCP liposomes upon incubation with ALP due to absence of such a PEG corona on the surface. [214] In order to overcome PEG-corona, phosphorylated surfactants with PEG spacer arms were utilized and Δ21.6 mV and Δ41.9 mV changes in zeta potential were achieved for POAP [218] and PNPP [104] containing formulations, respectively. Further evidence was provided by comparing the phosphate release efficiency of phosphorylated surfactants having been incorporated into SEDDS as illustrated in Figure 12 upon ALP treatment.…”

“…Promising strategy for developing zeta potential changing system [ 104] Decoration of NCs with polycationic cell penetrating peptide (CPP) followed by polyphosphate coating Poly-L-lysine decorated oily droplet coated with phytic acid and tripolyphosphate -4-fold Overcome polycation dilemma [ 105] Figure 14. ALP-activated cell-selective delivery of chemotherapeutic drug upon cell internalization.…”

WITHDRAWN: Bioengineering of Neem Colloidal Nano-Emulsion Formulation With Adjuvant for Better Surface Adhesion and Long Term Activity in Insect Control

“…Zeta potential values provide the information about the homogenous behavior of the nano-emulsion. Particles with zeta potential more positive than + 30 mV or more negative than -30 mV are usually considered to be stable, since electrical charge of droplets is strong enough to assume that repulsive forces between droplets are predominant in the nanoemulsion 60 .The surface of NE was negatively charged with an average zeta potential (−30 and −40mV) which indicates that the formulation is stable. A negative zeta potential value induces repulsive forces that are greater than the attraction forces among droplets, thus averting the coagulation and coalescence to occur in disperse emulsion.…”