A pH-Responsive Amphiphilic Hydrogel Based on Pseudopeptides and Poly(ethylene glycol) for Oral Delivery of Hydrophobic Drugs
Open accessAbstract
Oral administration is a noninvasive and convenient drug delivery route most preferred by patients. However, poor stability in the gastrointestinal tract and low bioavailability of hydrophobic drugs has greatly limited their oral administration. To address this problem, we report a pH-responsive, amphiphilic hydrogel drug carrier based on a pseudopeptide poly( l -lysine isophthalamide) (PLP) and poly(ethylene glycol) (PEG). The hydrogels were prepared by a simple N -(3-(dimethylamino)propyl)- N ′-ethyl carbodiimide hydrochloride (EDC)/ N -hydroxysuccinimide (NHS) coupling reaction, and the cross-linking was confirmed by infrared spectroscopy and differential scanning calorimetry analyses. Because of the pH-responsive conformational alteration of PLP, the hydrogels were relatively hydrophobic and collapsed at acidic pH, but became hydrophilic and swollen at neutral pH. The amphiphilicity enabled the hydrogels to well retain and protect hydrophobic model drugs in the simulated gastric fluid, but efficiently release them in the simulated intestinal fluid. These results suggested that the pH-responsive amphiphilic hydrogels are promising candidates for oral delivery of hydrophobic drugs.
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Cryogels with lower polymer content (2aNFC-1AP and 1aNFC-1AP) experienced a higher degree of carboxyl group protonation, producing stronger 1725 cm−1 signals.
“In this basis, cryogels with lower polymer content (i.e., 2aNFC-1AP and 1aNFC-1AP) experienced a higher degree of carboxyl group protonation, producing stronger 1725 cm−1 signals [38].”
From Amidated Pectin/Nanocellulose Hybrid Cryogel System with a pH-Responsive Release Profile for Small Intestinal Delivery (2025) · cites this paper as [38]
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“In this basis, cryogels with lower polymer content (i.e., 2aNFC-1AP and 1aNFC-1AP) experienced a higher degree of carboxyl group protonation, producing stronger 1725 cm − 1 signals [38].”
- Authors
- Wang, S., Attah, R., Li, J., Chen, Y., & Chen, R.
- Affiliations
- Imperial College London (GB)
- Corresponding author
- Chen, Rongjun
- Venue
- ACS Biomaterials Science & Engineering
- Publisher
- American Chemical Society (ACS)
- Published
- 2018-09-24
- Volume
- 4
- Issue
- 12
- Pages
- 4236-4243
- ISSN
- 2373-9878 (ISSN-L)
- OpenAlex
- W2893966129
- Cited by
- 29
- References
- 46
- Citations by year
- 2026: 2 · 2025: 5 · 2024: 2 · 2023: 2 · 2022: 6 · 2021: 6 · 2020: 1 · 2019: 5
- FWCI
- 1.14
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- cc-by
- Locations
- ACS Biomaterials Science & Engineering (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Spiral (Imperial College London) (submittedVersion)
- Spiral (Imperial College London) (submittedVersion, cc-by)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Medicine › Hydrogels: synthesis, properties, applications
- Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Pharmaceutical Science › Advanced Drug Delivery Systems
- Physical Sciences › Materials Science › Biomaterials › Supramolecular Self-Assembly in Materials
- Keywords
- pH-responsive hydrogels, amphiphilic hydrogels, pseudopeptides, polyethylene glycol, oral drug delivery, poorly water-soluble drugs, pH-dependent drug release, hydrogel crosslinking, bioavailability
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