Table 4.
Examples of capsules prepared by emulsion templating approach.
| Polymer Shell | Core & Type | Template & Organic Solvent | Emulsion Type | Method | APC & Location | Interactions | Crosslinkers; Stabilizers; & Surfactants | Surface Charge | Size | Encapsulation Efficiency |
Ref. |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Human serum albumin (HSA) | Lauroglycol 90; oily | Lauroglycol 90; Acetone |
o/w single emulsion |
Diffusion-evaporation | Exemestane and hesperetin; core |
Electrostatic interactions | None; 1:1w/w poloxamer/Tween 80 mixture; benzalkonium chloride |
20.7 ± 1.26 mV | 172.4 ± 8.6 nm | 95–98% | [10] |
| Folic acid-functionalized HSA | Oily; dodecane | Dodecane | o/w single emulsion |
Ultrasonic emulsification | - | Oxidative crosslinking | - | −20 mV | ~440 nm | - | [22] |
| Wheat germ agglutinin-functionalized HSA | Biocompatible plant oils; oily | Almond oil, rapeseed oil, olive oil, and linseed oil | o/w single emulsion |
Ultrasonic emulsification | - | Oxidative crosslinking | - | −12.4 ± 9.4 mV | (662.1 ± 7.6) nm to (862.2 ± 59.5 nm) |
- | [104] |
| Fluorescently tagged bovine serum albumin (BSA) shell; Shell filled with PLGA and unsaturated fatty linoleic acid |
Lecithin; aqueous | Dichloromethane and ethanol | w/o/w double emulsion |
Double emulsion–evaporation | lipophilic paclitaxel in the oily shell and hydrophilic transcription factor p53 in the aqueous core | - | Pluronic F-68 & Lecithin | −36.4 mV | ~180 nm | - | [25] |
| BSA | Soya bean oil; oily | Soya bean oil | o/w single emulsion |
Ultrasonic emulsification | Ribonucleic acid (RNA); shell | Oxidative crosslinking | - | −40 meV | (0.5 μm to 2.5 μm) | ~60% | [16] |
| Polyvinyl alcohol (PVA) functionalized-BSA | 0 meV | ||||||||||
| Polyethyleneimine (PEI) functionalized-BSA | +20 meV | ||||||||||
| Silk fibroin | Sodium alginate; solid | Paraffin oil | w/o single emulsion |
Emulsion-coacervation | - | Chemical crosslinking using glutaraldehyde | Span 80 | - | Avg. 141.839 μm. | - | [14] |
| Collagen and PLGA layers | Hollow | Dichloromethane | o/w single emulsion |
Emulsion–evaporation | MnO2 nanoparticles; shell | Carbodiimide initiated covalent crosslinking | Crosslinking facilitated by N-(3-Dimethylaminopropyl)-N′-ethyl carbodiimide hydrochloride (EDC), N-Hydroxysuccinimide (NHS); stabilizer: polyvinyl alcohol (PVA) |
- | - | - | [18] |
| Anti-epidermal growth factor receptor (EGFR) modified-BSA | Dodecane; oily | dodecane | o/w single emulsion |
Ultrasonic emulsification | Gemcitabine; shell | Oxidative crosslinking | - | - | ~1.1 μm | 30% | [20] |
| Whey protein isolate (WPI) | Sunflower oil; solid | Sunflower oil | o/w single emulsion |
Spray- and freeze-drying | Vitamin E; core | - | - | - | ~145.3 µm | 89.3% | [12] |
| Gelatin | Citric acid; solid | Dichloromethane and ethanol | o/w single emulsion |
Spray drying | Itraconazole; core |
Physical crosslinking | - | - | - | - | [21] |
| Tetramethylrhodamine-isothiocyanate labeled-BSA, tannic acid, and BSA layers | Sunflower oil; oily | Sunflower oil | o/w single emulsion |
Emulsion-coacervation | 3,4,9,10-tetra-(hectoxy-carbonyl)-perylene (THCP); core | Hydrogen bonding between the shell layers | - | (−30 ± 1.9) mV | - | - | [33] |
| Chitosan | Soybean oil, oily | Soybean oil; benzyl benzoate |
o/w single emulsion |
Emulsion-microfluidic | Tea tree oil; core |
Covalent interactions by chemical crosslinking | Terephthalaldehyde (TPA) | - | ~106 μm | 19.5–49.3% | [105] |
| Gelatin and gum arabica | Soybean oil; aqueous |
Soybean oil | w/o/w double emulsion |
Emulsion-complex coacervation | Sucralose; core |
Covalent interactions | Lecithin | 81 to 113 μm | 43.04 to 89.44% | [106] | |
| Folic acid-modified hyaluronic acid | Ethyl acetate; oily | Ethyl acetate | o/w single emulsion |
Ultrasonication | Curcumin; core | Oxidative crosslinking | - | - | 400 to 600 nm | 91.3 to 93.2% | [107] |
| Soy protein and gum arabica | (80 vol% NEOBEE M5 + 20 vol% limonene); oily |
80 vol% NEOBEE M5 + 20 vol% limo-nene |
o/w single emulsion |
Complex coacervation |
- | Heat-induced gelation crosslinking | - | - | - | - | [108] |
| Pea protein isolate and sugar beat pectin | Hemp seed oil; oily | Hemp seed oil | o/w single emulsion |
Complex coacervation, followed by spray-drying |
Hempseed oil | pH-induced crosslinking | - | - | (12.80 ± 2.17) to (23.70 ± 1.23) μm | (79.65 ± 5.99) to (94.42 ± 6.63)% | [109] |