Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and Humidity
This study prepared nanocapsules (NCs) with excellent self-controlled antimicrobial activity at pH 6–7 and humidity 45–100%, conditions in which most bacterial and fungal strains thrive. The nanocapsule substrate (NC@SiO<sub>2</sub>) was 676 nm in diameter, and the ligand-grafted capsule...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-01-01
|
| Series: | Pharmaceutics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1999-4923/14/2/280 |
| _version_ | 1797477242834518016 |
|---|---|
| author | Eunjoo Koh Yong Taek Lee |
| author_facet | Eunjoo Koh Yong Taek Lee |
| author_sort | Eunjoo Koh |
| collection | DOAJ |
| description | This study prepared nanocapsules (NCs) with excellent self-controlled antimicrobial activity at pH 6–7 and humidity 45–100%, conditions in which most bacterial and fungal strains thrive. The nanocapsule substrate (NC@SiO<sub>2</sub>) was 676 nm in diameter, and the ligand-grafted capsule (NC@SiO<sub>2</sub>-g-MAA) was 888 nm. The large surface area and outer ligand brush of the NCs induced a rapid, self-controlled antibacterial response in the pH and humidity conditions needed for industrial and medical applications. Ligand-brush NCs containing an anionic antimicrobial drug had a rapid release effect because of the repellent electrostatic force and swelling properties of the ligand brushes. Controlled release of the drug was achieved at pH 6 and humidity of 45% and 100%. As many carboxylic acid groups are deprotonated into carboxylic acids at pH 5, the NC@SiO<sub>2</sub>-g-MAA had a high negative charge density. Carboxylic acid groups are anionized (–COO<sup>−</sup>) at pH 6 and above and push each other out of the capsule, expanding the outer shell as in a polymer brush to create the release behavior. The surface potential of the NC intermediate (NC@SiO<sub>2</sub>-MPS) was −23.45 [mV], and the potential of the capsule surface decreased to −36.4 [mV] when the MAA ligand brushes were grafted onto the surface of the capsule intermediate. In an antimicrobial experiment using <i>Escherichia coli</i>, a clear zone of 13–20 mm formed at pH 6, and the <i>E. coli</i> was eradicated completely at pH 6 and pH 7 when the humidity was 100%. |
| first_indexed | 2024-03-09T21:14:48Z |
| format | Article |
| id | doaj.art-39ada60536e34288a09b249eaafacc82 |
| institution | Directory Open Access Journal |
| issn | 1999-4923 |
| language | English |
| last_indexed | 2024-03-09T21:14:48Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Pharmaceutics |
| spelling | doaj.art-39ada60536e34288a09b249eaafacc822023-11-23T21:36:37ZengMDPI AGPharmaceutics1999-49232022-01-0114228010.3390/pharmaceutics14020280Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and HumidityEunjoo Koh0Yong Taek Lee1Department of Chemical Engineering, Faculty of Chemical Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, KoreaDepartment of Chemical Engineering, Faculty of Chemical Engineering, Kyung Hee University, Deogyeong-daero, Giheung-gu, Yongin-si 17104, KoreaThis study prepared nanocapsules (NCs) with excellent self-controlled antimicrobial activity at pH 6–7 and humidity 45–100%, conditions in which most bacterial and fungal strains thrive. The nanocapsule substrate (NC@SiO<sub>2</sub>) was 676 nm in diameter, and the ligand-grafted capsule (NC@SiO<sub>2</sub>-g-MAA) was 888 nm. The large surface area and outer ligand brush of the NCs induced a rapid, self-controlled antibacterial response in the pH and humidity conditions needed for industrial and medical applications. Ligand-brush NCs containing an anionic antimicrobial drug had a rapid release effect because of the repellent electrostatic force and swelling properties of the ligand brushes. Controlled release of the drug was achieved at pH 6 and humidity of 45% and 100%. As many carboxylic acid groups are deprotonated into carboxylic acids at pH 5, the NC@SiO<sub>2</sub>-g-MAA had a high negative charge density. Carboxylic acid groups are anionized (–COO<sup>−</sup>) at pH 6 and above and push each other out of the capsule, expanding the outer shell as in a polymer brush to create the release behavior. The surface potential of the NC intermediate (NC@SiO<sub>2</sub>-MPS) was −23.45 [mV], and the potential of the capsule surface decreased to −36.4 [mV] when the MAA ligand brushes were grafted onto the surface of the capsule intermediate. In an antimicrobial experiment using <i>Escherichia coli</i>, a clear zone of 13–20 mm formed at pH 6, and the <i>E. coli</i> was eradicated completely at pH 6 and pH 7 when the humidity was 100%.https://www.mdpi.com/1999-4923/14/2/280controlled drug releaseself-antibacterial activityligand brush nanocapsulepH and humidity responsecytotoxicity |
| spellingShingle | Eunjoo Koh Yong Taek Lee Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and Humidity Pharmaceutics controlled drug release self-antibacterial activity ligand brush nanocapsule pH and humidity response cytotoxicity |
| title | Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and Humidity |
| title_full | Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and Humidity |
| title_fullStr | Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and Humidity |
| title_full_unstemmed | Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and Humidity |
| title_short | Preparation of Ligand Brush Nanocapsules for Robust Self-Controlled Antimicrobial Activity with Low Cytotoxicity at Target pH and Humidity |
| title_sort | preparation of ligand brush nanocapsules for robust self controlled antimicrobial activity with low cytotoxicity at target ph and humidity |
| topic | controlled drug release self-antibacterial activity ligand brush nanocapsule pH and humidity response cytotoxicity |
| url | https://www.mdpi.com/1999-4923/14/2/280 |
| work_keys_str_mv | AT eunjookoh preparationofligandbrushnanocapsulesforrobustselfcontrolledantimicrobialactivitywithlowcytotoxicityattargetphandhumidity AT yongtaeklee preparationofligandbrushnanocapsulesforrobustselfcontrolledantimicrobialactivitywithlowcytotoxicityattargetphandhumidity |