Controlling drug delivery from polymer microspheres by exploiting the complex interrelationship of excipient and drug crystallization

Abstract

Semicrystalline polymers are often used as macromolecular excipients in active pharmaceutical ingredient (API)‐delivery systems. In such systems, the morphological structure and crystalline characteristics of the excipient have a direct impact upon the drug‐delivery rate. In this study, polycaprolactone (PCL)‐based microspheres prepared via melt‐printing were loaded with 10, 30, and 50% ibuprofen (IBU). In vitro release studies showed that, for a constant amount of IBU, the API was released fastest from the 30%‐loaded microspheres, followed by the 50%‐ and 10%‐loaded microspheres. The discrepancy in these release rates was investigated using scanning electron microscopy, differential scanning calorimetry, X‐ray diffraction, and thermodynamic analyses, revealing the complex morphological and crystalline interrelationships of PCL and IBU. Although it is generally accepted that the degree of crystallinity of the excipient is the main factor controlling the release of the API, we found that the crystallite size of the small‐molecule API is of primary importance. Moreover, these factors, which are controllable via the parameters used in melt‐based preparation, can be exploited to tune drug‐release rates. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47227.

Electrospinning: A promising technique for drug delivery systems

“…Also, the semi-crystalline and crystalline structure of the excipient have a direct influence upon the drug delivery rate due to the crystalline interrelationship between the excipient or polymer and the active ingredient. XRD is used to characterize this interrelationship [94].…”

Kinetics of Drug Release via Nicardipine Hydrochloride‐loaded Carboxymethyl Cellulose/Poly(D,L‐lactic‐co‐glycolic acid) Nanocarriers Using a Contemporary Emulsion Process

“…This study focused on NCH-CMC/PLGA nanocarrier synthesis for use as a drug delivery system. Hence, the drug encapsulation capacity of the nanocarriers is an important factor and can be calculated with Equation (2). The results presented in Table 2 reveal that the nanocarriers generally had drug encapsulations of more than 90%.…”

“…[1] Nanocarriers are similar to a rocket device that protects the extended shelf life of a drug, delivers a drug to the targeted site, and maintains therapeutic drug concentrations. [2] In recent years, significant advances have been achieved in the nanotechnology and nanomedicine fields in development and design of drug delivery systems. [3] In comparison with conventional drug dosage forms, drug delivery systems have the advantages of protective drug control for safe deactivation, enhanced bioavailability, reduced toxic and side effects of drugs, effectively improved transport to the target organ, and improved pharmacokinetics, which can effectively extend the action of a scheduled drug with potentially time-critical activity.…”

“…Nanocarriers are a novel nanometer‐scale drug carrier in manufacturing and usually have a size between 1 nm and 1,000 nm, resulting in a high surface area to volume ratio for enhanced interaction with the targeted site [1] . Nanocarriers are similar to a rocket device that protects the extended shelf life of a drug, delivers a drug to the targeted site, and maintains therapeutic drug concentrations [2] . In recent years, significant advances have been achieved in the nanotechnology and nanomedicine fields in development and design of drug delivery systems [3] .…”

Synthesis of amino‐cosubstituted polyorganophosphazenes and fabrication of their nanoparticles for anticancer drug delivery

“…[7][8][9][10][11] Polymeric materials are able to form a wide range of different nanoparticulate structures, which can improve the therapeutic capability to fulfill the demands of modern medicine to cure different diseases such as cancer. [12][13][14][15][16][17][18][19][20] The polymeric nanoparticles have played a significant role in the development of more effective drug delivery systems. [21][22][23][24] The nanoparticles are enough small in size to cross the cell barriers and circulate for a longer time in the bloodstream until reach the targeted sites.…”