Characterisation data of water-soluble hydrophilic and amphiphilic dendrimer
prodrugs for delivering bioactive chemical entities otherwise non-soluble
S. Alfei, A. Spallarossa, S. Catena, F. Turrini, G. Zuccari, A. Pittaluga, R. Boggia
References.
1. Alfei, S., Castellaro, S., Taptue, G.B. Org. Commun., 2017, 10, 144. 2. Alfei, S., Castellaro, S., Macromol. Res., 2017, 25, 1172. 3. Alfei, S., Catena, S. Polym. Int., 2018, 67, 1572. 4. Alfei, S., Catena, S. Polym. Adv. Technol., 2018, 24, 153. 5. Alfei, S. Taptue, G. B. et al., Chinese J. Polym. Sci., 2018, 36, 999. 6. Alfei, S. Catena, S., et al., Eur. J. Phar. Sci., 2018, 124, 153. 7. Alfei, S., Turrini, F. et al., New J. Chem., 2019, 43, 2438.
Our DDSs.
By using only MeOH and through a physical process, the bioactive, but water-insoluble Ursolic+Oleanolic acids UOA(1+1’), the thiocarbamate derivative O-TC (2) and Ellagic acid EA (3) were enclosed into the prepared hydrophilic and amphiphilic
polycationic carriers, achieving a series of biocompatible, water-soluble prodrugs with maintained bioactivity,improved bioavailability
and endowed with other nonpareil properties that make them advisable for clinical applications (Fig. 1, Fig. 2 and Fig. 3).5,6,7
The outstanding problem…
More than 40% of bioactive chemical entities (BCEs) developed in pharmaceuticals studies or naturally occurring, are almost water-insoluble, poorly orally bioavailable, quickly metabolised and barely effective in vivo and this strongly limits their clinical applications as therapeutics. Drug Delivery, making use of Drug Delivery Systems (DDSs), aims at overcoming these obstacles and at succeeding in solubilising, protecting, transporting and releasing the problematic BCEs ideally only where necessary, maintaining the therapeutic concentration for a long period.Fig.1. An intuitive representation of the six
UOA(1+1’)-DDSs prepared.
COOH
H
3C
CH
3CH
3HO
H
3C
CH
3CH
3H
3C
COOH
CH
3CH
3HO
H
3C
H
3C
CH
3H
3C
CH
3 UOA 1+1’Fig.2. An intuitive representation of the
five O-TC(2)-DDSs prepared. Fig. 3.EA(3)-DDSs obtained.An intuitive representation of the two
O
O
O
O
HO
HO
OH
OH
EA 3N
H
O
OH
O
O
H
N
S
CH
3O-TC DDSs characterisation
UOA DDSs characterisation
EA DDSs characterisation
Example of comparison between 1H-NMR of
EA(3) (b), dendrimer carrier (a) and DDS (c)
UOA
Dendrimer
DDS
Example of comparison between 1H-NMR of
UOA 1+1’ (a), dendrimer carrier (b) and DDS (c)
Solubility improvement Example of comparison between 1H-NMR of
O-TC 2 (a), dendrimer carrier (b) and DDS (c)
Average buffer capacity
0 10 20 30 40 50 0 10 20 30 40 50 60 70 80 90 100 110 Time (h) R el eas e of U O A (µg/10mg d en driple x)
UOA release profile
0 0,1 0,2 0,3 0,4 0,400 0,2000,250 0,167 0.070 0,157 0.041 0.018 0.017 dV (ml)/ dpH
Average buffer capacity (pH 4,5-7,5)*
D D S 1 D D S 2 D D S 3 D D S 4 D D S 6 D D S 5 PA M AM 1 PA M AM2 PA M AM 3 DDS DDS1 6 16.8 DDS2 7 19.0 DDS3 4 12.5 DDS4 3 5.0 DDS5 12 16.1 DDS6 8 7.9 UOAa wt/wt % Z-P 22.2 15.5 24.8 34.0 30.7 31.8 Z-AVE 30.6 36.3 24.9±1.1 16.1 35.9 20.3
aunits of UOA complexed per dendrimer mole as estimated by 1H NMR spectra.
Z-potential (mV) and particle size (nm)
ROS Help!! O-TC 2 0 50 100 11 9,3 53 57 47 0 33 33 53 57 47 0 10,6 2,3 3,2 28,5 4,7 0 mg/ml Comp.
Water Methanol Ethanol
DDS1 DDS3 DDS2 O-TC2 DDS5 DDS4 0 0,2 0,4 0,6 0.041 0.018 0.017 0,517 0.398 0.348 0.411 0.341 0,189 dV(ml) dpH PHis Arg DDS5 DDS4 DDS3 DDS2 DDS1 PEI PG4 PArg 0 10 20 30 40 0 10 20 30 40 50 60 70 80 90 100 110 Time (h) Release of 1 (µg/10mg dendriplex) 7 8 9 10 11
O-TC 2 release profile
DDS1 DDS2 DDS3 DDS4 DDS5 0,000 5,000 10,000 15,000 0,200 0,000 15,000 0,097 9,000 3,200 mg/ml COMPOUNDS EtOH Water Ellagic acid DDS1 DDS2 0 0,02 0,04 0,06 0,08 0,1 0,12 0,14 0,04127 0,018180,01717 0,10000 0,127000 dV(ml)/dpH
(1) Average buffer capacity
PAMAM3 PAMAM2 PAMAM1 DDS1 DDS2 0 20 40 60 80 100 120 0 20 40 60 80 100 EA DDS2 DDS1 RSA%
Background.
Since 2009 our research has been focused on the synthesis of dendrimer delivery systems made up of an uncharged polyester-based matrix and of a polycationic shell consisting of amino acids. At the beginning, several fourth, fifth and sixth generation (G4, G5, G6) hydrophilic, amino acids-modified dendrimer scaffolds not containing arginine, were prepared and addressed to gene therapy. All the materials, subsequently prepared, were instead addressed to drug delivery. Polyester-based hydrophilic dendrimers containing also arginine and dipeptides were developed until 2014. Starting from 2015, new uncharged dendrimer scaffolds with a tri- or tetra-hydroxyl core and equipped with a C-18 hydrocarbon chain, possessing amphiphilic features, have been synthesized. They were peripherally esterified either with arginine only, or with a mix of arginine and lysine or with a mix of arginine, lysine, methyl and dimethyl glycine. This last uncommon esterification requested novel proper protocols that were set up on aroutinely prepared G4OH polyester-based dendrimer belonging to the initial production, that was selected as template molecule.1,2,3,4
ROS
ROS HD-1+ AD-3+ HD-1,2+ MEMTs, AD-3+First arginine hydrophilic dendrimers Solubility improvement O-TC Dendrimer DDS DDS Thanks !!!
