Supporting Information Available.
General procedures and analytical data for 2-7.
2 was synthesized according to the well-known protocol described by I. Ugi, POCl3/NEt3 method
(Ugi I, Fetzer U, Eholzer U, Knupfer H, Offermann K (1965) Isonitrile Synthesen. Angew. Chem.
77:492-504).
Mp= 71°С. 1H NMR (400 MHz, DMSO-d6) δ: 1.74-1.83 (2Н, m, СН2), 2.25-2.48 (6H, m, NCH2),
3.35-3.49 (2Н, m, СН2). MS (m/z, %):220 [M+] (28), 219(7), 190 (14), 180 (13), 176 (6), 166 (36), 165
(11), 164 (49), 152 (19), 139 (24), 123 (72), 97 (74), 84 (64), 70(100), 56 (83). IR (cm-1): 1310 (-C-N),
1448 (-C-C-), 2150 (-N≡C), 2801 (-C-H)), 2982 (-CH-).
3 Pectinic acid (0.5 g) was dissolved under moderate stirring in a 500 ml solution of Na2CO3 (170 mg)
in deionized water. The resulting mixture was treated with solution of benzylamine (300 μl) in 15 ml of
0.1 M HCl (0.5 molar ratio). After 10 min, cross-linking agent 1,4-bis(3-isocyanopropyl)piperazine (27
mg (a); 56 mg (b); 72 mg (c); 105 mg (d); 128 mg (e)) was added to the solution and homogenized with
manual shaking. After 1h, excess of formaldehyde (30% solution in water, 300 μl) was added to the
reaction mixture. The visible turbidity of the mixture was observed that was an indicator of the reaction
rate (typical reaction time is 1-2 min). The pH of the solution should be in a range of pH = 8-8.5 during
all reaction time. After 3 h, the reaction mixture was filtered through Millipore membrane (0.45 μm)
and the resulting solution was directly used for DLS measurement. For obtaining of samples of pure
microgels 0.1 M solution of HCl was dropped into the reaction mixture until formation of macroscopic
gel was observed (isoelectric point), washed with deionized water and centrifuged at 4000 g for 30 min.
The precipitate of microgel was washed with acetone three times and centrifuged at 4000 g for 30 min.
Finally, the product was dried at room temperature under vacuum for 24 h to yield white powder of
pectinic acid microgel. All stages were performed at 25C.
3a DLS: Average diameter 287 nm, polydispersity index 0.17, zeta potential -41 mV (pH 8.5).
1
H NMR (400 MHz, DMSO-d6) δ: 1.54-1.62 (2H, m, CH2), 2.25-2.45 (6H, m, NCH2), 3.10-3.25 (2H,
1
m, CH2), 3.68 (2H, br.s., CH2), 3.77 (1H, br.s, CH), 3.96 (1H, br.s, CH), 4.31-4.35 (2H, m, CH2), 4.43
(1H, br.s, CH), 4.68 (1H, br.s, CH), 5.10 (1H, br.s, CH), 7.22-7.30 (4H, m, Ph) Calculated cross-linkage
density 6.9%.
IR (cm-1): 1045 (C-O), 1538 (NH), 1663 (C=O), 2210 (NH).
3b DLS: Average diameter 361 nm, polydispersity index 0.14, zeta potential -34 mV (pH 8.5).
1
H NMR (400 MHz, DMSO-d6) δ: 1.53-1.61 (2H, m, CH2), 2.26-2.44 (6H, m, NCH2), 3.12-3.25 (2H,
m, CH2), 3.69 (2H, br.s., CH2), 3.78 (1H, br.s, CH), 3.97 (1H, br.s, CH), 4.25-4.31 (2H, m, CH2), 4.42
(1H, br.s, CH), 4.69 (1H, br.s, CH), 5.08 (1H, br.s, CH), 7.20-7.29 (4H, m, Ph) Calculated cross-linkage
density 15.0%.
IR (cm-1): 1046 (C-O), 1536 (NH), 1665 (C=O), 2212 (NH).
3c DLS: Average diameter 303 nm, polydispersity index 0.12, zeta potential -30 mV (pH 8.5);
average diameter 295 nm, polydispersity index 0.13, zeta potential 17 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 1.50-1.72 (2H, m, CH2), 2.25-2.40 (2H, m, NCH2), 2.40-2.55 (4H,
m, NCH2); 3.10-3.30 (2H, m, CH2), 3.65 (2H, br.s., CH2), 3.73 (1H, br.s, CH), 3.93 (1H, br.s, CH),
4.40-4.50 (2H, m, CH2), 4.50 (1H, br.s, CH), 4.69 (1H, br.s, CH), 5.15 (1H, br.s, CH), 7.21-7.31 (4H,
m, Ph) Calculated cross-linkage density 21.3%.
IR (cm-1): 1047 (C-O), 1535 (NH), 1662 (C=O), 2210 (NH).
3d DLS: Average diameter 239 nm, polydispersity index 0.09, zeta potential -28 mV (pH 8.5);
average diameter 226 nm, polydispersity index 0.10, zeta potential 19 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 1.55-1.65 (2H, m, CH2), 2.27-2.48 (6H, m, NCH2), 3.09-3.23 (2H,
m, CH2), 3.69 (2H, br.s., CH2), 3.76 (1H, br.s, CH), 3.96 (1H, br.s, CH), 4.24-4.31 (2H, m, CH2), 4.43
(1H, br.s, CH), 4.69 (1H, br.s, CH), 5.09 (1H, br.s, CH), 7.22-7.32 (4H, m, Ph) Calculated cross-linkage
density 26.7%.
IR (cm-1): 1044 (C-O), 1536 (NH), 1664 (C=O), 2211 (NH).
3e DLS: Average diameter 235 nm, polydispersity index 0.15, zeta potential -29 mV (pH 8.5);
2
average diameter 240 nm, polydispersity index 0.17, zeta potential 21 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 1.53-1.65 (2H, m, CH2), 2.25-2.43 (6H, m, NCH2), 3.13-3.25 (2H,
m, CH2), 3.67 (2H, br.s., CH2), 3.76 (1H, br.s, CH), 3.97 (1H, br.s, CH), 4.25-4.32 (2H, m, CH2), 4.43
(1H, br.s, CH), 4.68 (1H, br.s, CH), 5.10 (1H, br.s, CH), 7.22-7.30 (4H, m, Ph) Calculated cross-linkage
density 32.1%.
IR (cm-1): 1046 (C-O), 1536 (NH), 1664 (C=O), 2145 (-N≡C), 2211 (NH).
4 Pectinic acid (0.5 g) was dissolved under moderate stirring in a 500 ml solution of Na2CO3 (170 mg)
in deionized water. The resulting mixture was treated with solution of furfurylamine (255 μl) in 15 ml of
0.1 M HCl (0.5 molar ratio). After 10 min, cross-linking agent 1,4-bis(3-isocyanopropyl)piperazine (55
mg (a); 104 mg (b)) was added to the solution and homogenized with manual shaking. After 1h, excess
of formaldehyde (30% solution in water, 300 μl) was added to the reaction mixture. The pH of the
solution should be in a range of pH = 8-8.5 during all reaction time. After 3 h, the reaction mixture was
filtered through Millipore membrane (0.45 μm) and the resulting solution was directly used for DLS
measurement. For obtaining of samples of pure microgels 0.1 M solution of HCl was dropped into the
reaction mixture until formation of macroscopic gel was observed (isoelectric point), washed with
deionized water and centrifuged at 4000 g for 30 min. The precipitate of microgel was washed with
acetone three times and centrifuged at 4000 g for 30 min. Finally, the product was dried at room
temperature under vacuum for 24 h to yield white powder of pectinic acid microgel. All stages were
performed at 25C.
4a DLS: Average diameter 278 nm, polydispersity index 0.23, zeta potential -35 mV (pH 8.5).
1
H NMR (400 MHz, DMSO-d6) δ: 1.59-1.73 (2H, m, CH2), 2.22-2.55 (6H, m, NCH2), 3.10-3.45 (2H,
m, CH2), 3.73 (2H, s, CH2), 3.75 (1H, br.s, CH), 3.96 (1H, br.s, CH), 4.12 (2H, br.s, CH2), 4.42 (1H,
br.s, CH), 4.68 (1H, br.s, CH), 5.09 (1H, br.s, CH), 6.32-6.53 (2H, m, Furan), 7.50-7.61 (1H, m, Furan)
Calculated cross-linkage density 14.9%.
IR (cm-1): 1053 (C-O), 1537 (NH), 1665 (C=O), 2213 (NH).
3
4b DLS: Average diameter 241 nm, polydispersity index 0.25, zeta potential -32 mV (pH 8.5);
average diameter 235 nm, polydispersity index 0.24, zeta potential 20 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 1.60-1.78 (2H, m, CH2), 2.20-2.57 (6H, m, NCH2), 3.08-3.45 (2H,
m, CH2), 3.74 (2H, s, CH2), 3.75 (1H, br.s, CH), 3.96 (1H, br.s, CH), 4.06 (2H, br.s, CH2), 4.42 (1H,
br.s, CH), 4.67 (1H, br.s, CH), 5.09 (1H, br.s, CH), 6.30-6.55 (2H, m, Furan), 7.48-7.65 (1H, m, Furan)
Calculated cross-linkage density 27.6%.
IR (cm-1): 1052 (C-O), 1538 (NH), 1664 (C=O), 2215 (NH).
5 Pectinic acid (0.5 g) was dissolved under moderate stirring in a 500 ml solution of Na2CO3 (170 mg)
in deionized water. The resulting mixture was treated with solution of 4-picolylamine (300 μl) in 15 ml
of 0.1 M HCl (0.5 molar ratio). After 10 min, cross-linking agent 1,4-bis(3-isocyanopropyl)piperazine
(52 mg (a); 96 mg (b)) was added to the solution and homogenized with manual shaking. After 1h,
excess of formaldehyde (30% solution in water, 300 μl) was added to the reaction mixture. The pH of
the solution should be in a range of pH = 8-8.5 during all reaction time. After 3 h, the reaction mixture
was filtered through Millipore membrane (0.45 μm) and the resulting solution was directly used for
DLS measurement. For obtaining of samples of pure microgels 0.1 M solution of HCl was dropped into
the reaction mixture until formation of macroscopic gel was observed (isoelectric point), washed with
deionized water and centrifuged at 4000 g for 30 min. The precipitate of microgel was washed with
acetone three times and centrifuged at 4000 g for 30 min. Finally, the product was dried at room
temperature under vacuum for 24 h to yield white powder of pectinic acid microgel. All stages were
performed at 25C.
5a DLS: Average diameter 265 nm, polydispersity index 0.24, zeta potential -34 mV (pH 8.5);
average diameter 260 nm, polydispersity index 0.21, zeta potential 19 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 1.52-1.69 (2H, m, CH2), 2.21-2.50 (6H, m, NCH2), 3.09-3.43 (2H,
m, CH2), 3.72 (2H, s, CH2), 3.76 (1H, br.s, CH), 3.97 (1H, br.s, CH), 4.24-4.37 (2H, m, CH2), 4.42 (1H,
br.s, CH), 4.68 (1H, br.s, CH), 5.10 (1H, br.s, CH), 7.32-7.39 (2H, m, Pyr), 8.40-8.45 (1H, m, Pyr)
4
Calculated cross-linkage density 15.2%.
IR (cm-1): 1050 (C-O), 1536 (NH), 1664 (C=O), 2212 (NH).
5b DLS: Average diameter 253 nm, polydispersity index 0.26, zeta potential -31 mV (pH 8.5);
average diameter 256 nm, polydispersity index 0.25, zeta potential 28 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 1.55-1.69 (2H, m, CH2), 2.19-2.49 (6H, m, NCH2), 3.09-3.44 (2H,
m, CH2), 3.70 (2H, s, CH2), 3.76 (1H, br.s, CH), 3.96 (1H, br.s, CH), 4.34 (2H, br.s, CH2), 4.42 (1H,
br.s, CH), 4.68 (1H, br.s, CH), 5.11 (1H, br.s, CH), 7.33-7.39 (2H, m, Pyr), 8.42-8.47 (1H, m, Pyr)
Calculated cross-linkage density 26.3%.
IR (cm-1): 1054 (C-O), 1539 (NH), 1665 (C=O), 2214 (NH).
6 Pectinic acid (0.5 g) was dissolved under moderate stirring in a 500 ml solution of Na2CO3 (170 mg)
in deionized water. The resulting mixture was treated with solution of 3-(diethylamino)propylamine
(450 μl) in 15 ml of 0.1 M HCl (0.5 molar ratio). After 10 min, cross-linking agent 1,4-bis(3isocyanopropyl)piperazine (57 mg (a); 105 mg (b)) was added to the solution and homogenized with
manual shaking. After 1h, excess of formaldehyde (30% solution in water, 300 μl) was added to the
reaction mixture. The pH of the solution should be in a range of pH = 8-8.5 during all reaction time.
After 3 h, the reaction mixture was filtered through Millipore membrane (0.45 μm) and the resulting
solution was directly used for DLS measurement. For obtaining of samples of pure microgels 0.1 M
solution of HCl was dropped into the reaction mixture until formation of macroscopic gel was observed
(isoelectric point), washed with deionized water and centrifuged at 4000 g for 30 min. The precipitate of
microgel was washed with acetone three times and centrifuged at 4000 g for 30 min. Finally, the
product was dried at room temperature under vacuum for 24 h to yield white powder of pectinic acid
microgel. All stages were performed at 25C.
6a DLS: Average diameter 292 nm, polydispersity index 0.20, zeta potential -33 mV (pH 8.5);
average diameter 311 nm, polydispersity index 0.21, zeta potential 32 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 0.96 (6H, t, J=7.1 Hz, 2CH3), 1.56-1.64 (4H, m, 2CH2), 2.28-2.46
5
(12H, m, NCH2), 3.11-3.24 (4H, m, 2CH2), 3.64 (2H, br.s., CH2), 3.75 (1H, br.s, CH), 3.96 (1H, br.s,
CH), 4.20-4.28 (2H, m, CH2), 4.42 (1H, br.s, CH), 4.68 (1H, br.s, CH), 5.09 (1H, br.s, CH) Calculated
cross-linkage density 14.8%.
IR (cm-1): 1046 (C-O), 1534 (NH), 1662 (C=O), 2212 (NH).
6b DLS: Average diameter 260 nm, polydispersity index 0.19, zeta potential -30 mV (pH 8.5);
average diameter 267 nm, polydispersity index 0.20, zeta potential 36 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 0.97 (6H, t, J=7.0 Hz, 2CH3), 1.56-1.61 (4H, m, 2CH2), 2.30-2.75
(12H, m, NCH2), 3.21-3.41 (4H, m, 2CH2), 3.74-3.99 (2H, m, CH2), 3.77 (1H, br.s, CH), 3.96 (1H, br.s,
CH), 4.19-4.27 (2H, br.s, CH2), 4.42 (1H, br.s, CH), 4.68 (1H, br.s, CH), 5.10 (1H, br.s, CH) Calculated
cross-linkage density 26.5%.
IR (cm-1): 1049 (C-O), 1538 (NH), 1667 (C=O), 2215 (NH).
7 Pectinic acid (0.5 g) was dissolved under moderate stirring in a 500 ml solution of Na2CO3 (170 mg)
in deionized water. The resulting mixture was treated with solution of 4-fluorobenzylamine (325 μl) in
15 ml of 0.1 M HCl (0.5 molar ratio). After 10 min, cross-linking agent 1,4-bis(3isocyanopropyl)piperazine (58 mg (a); 107 mg (b)) was added to the solution and homogenized with
manual shaking. After 1h, excess of formaldehyde (30% solution in water, 300 μl) was added to the
reaction mixture. The visible turbidity of the mixture was observed that was an indicator of the reaction
rate (typical reaction time is 1-2 min). The pH of the solution should be in a range of pH = 8-8.5 during
all reaction time. After 3 h, the reaction mixture was filtered through Millipore membrane (0.45 μm)
and the resulting solution was directly used for DLS measurement. For obtaining of samples of pure
microgels 0.1 M solution of HCl was dropped into the reaction mixture until formation of macroscopic
gel was observed (isoelectric point), washed with deionized water and centrifuged at 4000 g for 30 min.
The precipitate of microgel was washed with acetone three times and centrifuged at 4000 g for 30 min.
Finally, the product was dried at room temperature under vacuum for 24 h to yield white powder of
pectinic acid microgel. All stages were performed at 25C.
6
7a DLS: Average diameter 340 nm, polydispersity index 0.15, zeta potential -34 mV (pH 8.5)
1
H NMR (400 MHz, DMSO-d6) δ: 1.55-1.62 (2H, m, CH2), 2.28-2.60 (6H, m, NCH2), 3.16-3.40 (2H,
m, CH2), 3.74 (2H, s, CH2), 3.75 (1H, br.s, CH), 3.97 (1H, br.s, CH), 4.20 (2H, br.s, CH2), 4.43 (1H,
br.s, CH), 4.67 (1H, br.s, CH), 5.09 (1H, br.s, CH), 7.08-7.42 (4H, м, Ar) Calculated cross-linkage
density 15.4%.
IR (cm-1): 1051 (C-O), 1537 (NH), 1665 (C=O), 2214 (NH).
7b DLS: Average diameter 313 nm, polydispersity index 0.13, zeta potential -27 mV (pH 8.5);
average diameter 302 nm, polydispersity index 0.12, zeta potential 18 mV (pH 2.0).
1
H NMR (400 MHz, DMSO-d6) δ: 1.56-1.68 (2H, m, CH2), 2.28-2.72 (6H, m, NCH2), 3.11-3.34 (2H,
m, CH2), 3.74 (2H, br.s, CH2), 3.75 (1H, br.s, CH), 3.96 (1H, br.s, CH), 4.23 (2H, br.s, CH2), 4.43 (1H,
br.s, CH), 4.67 (1H, br.s, CH), 5.09 (1H, br.s, CH), 7.11-7.39 (4H, м, Ar) Calculated cross-linkage
density 27.1%.
IR (cm-1): 1045 (C-O), 1540 (NH), 1668 (C=O), 2215 (NH).
Figure S1. 1H NMR spectrum of pectinic acid in D2O.
7
Figure S2. Typical 1H NMR spectrum of cross-linked microgel 3c.
Table S1. DLS data for colloidal salts of pectinic acid.
Sample
Amine
Distribution of particles Average
hydrodynamic Polydispersity
diameters (NNLS), nm
index
3
Benzylamine
Bimodal
42; 235
0.26
4
Furfurylamine
Bimodal
37; 220
0.30
5
4-Picolylamin
Bimodal
38; 214
0.28
6
3-(Diethylamino)
Multimodal
35; 89; 229
0.42
Bimodal
40; 242
0.25
propylamine
7
4-Fluorobenzylamine
8
Figure S3. Visualization of interfacial films using the formation of complex with -carotene dissolved
in oil phase. The colored complex membrane is brittle and can be broken during the agitation of
emulsion.
Figure S4. Detailed picture of the broken interfacial film.
9