Lalitkumar K Vora, Hannah McMillian, Deepakkumar Mishra, David Jones, Raghu Raj Singh Thakur
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引用次数: 0
Abstract
In recent years, there has been a surge of research focused on in situ-forming implants as a method of localized drug delivery. Despite advancements, the predominant challenge in situ-forming solvent-induced phase inversion (SIPI) implants is significant burst release which typically occurs within the first 24 hours post-administration. Another notable challenge is the real-time characterization of these implants, which is crucial for understanding their in situ formation and degradation mechanism. This study explores the impact of various hydrophilic polymers-hydroxypropyl methylcellulose (HPMC), hydroxypropyl cellulose (HPC), Carbopol, and carboxymethylcellulose (CMC) - on implant formation and drug release. SIPI systems, which are commonly composed of poly(lactic-co-glycolic acid) (PLGA) and N-methyl pyrrolidone (NMP), offer localized, controlled drug release but suffer from an initial burst within 24 hours post-administration. The incorporation of hydrophilic polymers aims to modulate this release and improve implant properties. For first-time, optical coherence tomography (OCT) imaging was employed for non-invasive assessment of the rate of in situ phase inversion and the resulting implant morphology, whereas scanning electron microscopy (SEM) and digital microscopy provided further insights into the internal structure of the implants. The results demonstrated that the inclusion of polymers such as HPMC and Carbopol effectively reduced burst release, whereas polymers such as HPC and CMC exhibited faster phase inversion, resulting in a more porous implant morphology and greater burst release. Additionally, the mechanical properties and mucoadhesive capabilities of the formulations were tested, suggesting that Carbopol-enhanced implants are particularly suitable for applications requiring prolonged retention at mucosal sites. This investigation provides critical insights into the design and optimization of SIPI systems for drug delivery.
期刊介绍:
The Journal of Pharmaceutical Sciences will publish original research papers, original research notes, invited topical reviews (including Minireviews), and editorial commentary and news. The area of focus shall be concepts in basic pharmaceutical science and such topics as chemical processing of pharmaceuticals, including crystallization, lyophilization, chemical stability of drugs, pharmacokinetics, biopharmaceutics, pharmacodynamics, pro-drug developments, metabolic disposition of bioactive agents, dosage form design, protein-peptide chemistry and biotechnology specifically as these relate to pharmaceutical technology, and targeted drug delivery.