Coaxial electrospinning and release characteristics of cellulose acetate–gelatin blend encapsulating a model drug

Abstract

In order to minimize the degradation of encapsulated compounds in the harsh environment of release medium and to minimize bursting release, a model drug was encapsulated in a kernel of ultrafine cellulose acetate (CA) and gelatin (GL) blend fibers via coaxial electrospinning. The effects of the GL ratio on the properties of the shell solution were investigated, along with the core-to-shell ratio. Transmission electron microscopy images showed that core-shell coaxial fibers were fabricated successfully. Scanning electron microscopy images showed that the average diameter of the fibers was 913 6 180 nm. As the GL ratio was increased, the viscosity of the shell solution decreased. In addition, more pronounced shear thinning occurred, which resulted in coaxial fibers with thinner shells. Release characteristics of the encapsulated amoxicillin in pepsin-containing simulated gastric fluid (SGF) with a pH of 1.2 were also investigated. It showed that the release of amoxicillin occurs owing to Fickian diffusion mechanism, with the release half-time being approximately 5 h. Bursting release was not observed, and fibers exposed to the SGF remained intact even after 24 h. These core-shell fibers should be suitable for applications requiring the sustained release of compounds in the gastrointestinal tract.

Designing emulsions and nanostructures for the encapsulation of bioactive compounds

“…Addition of HW in the emulsions leads to a decrease on the conductivity. For instance, conductivity of UTHW (1.3 mS/m) is well below that of BLUT (3 mS/m), with the first being comparable to the data obtained by Kiatyongchai et al (2014). This is probably due to the complexes that are formed between WPI and EGCG and mentioned earlier.…”

“…By this method, the components immiscibility problem is solved (Pérez-Masiá et al, 2014). Various studies have been shown the potential use of coaxial electrospraying mostly in pharma applications (Cao et al, 2014;Kiatyongchai et al, 2014).…”

Coaxially electrospun fiber-based microbicides facilitate broadly tunable release of maraviroc

“…Most reports of tunable and sustained release from coaxial fibers describe the delivery of macromolecules (e.g., proteins and nucleic acids) [8–11] or hydrophobic small molecules [10,12–14], where sustained release is aided by their large size, poor solubility or favorable partitioning into insoluble polymers. For hydrophilic small molecules that are often incompatible with hydrophobic polymers used for sustained release, low drug loading into the core of a coaxial fiber can facilitate slow drug release [15–17,21]. Here, we show high drug loading (up to 39 wt% in core-shell fibers) of a hydrophilic small molecule drug and sustained release over at least 5 days in vitro by ensuring compatibility between maraviroc, EC, and PVP.…”

Physical–Chemical Aspects of the Preparation and Drug Release of Electrospun Scaffolds

“…Consequently, quite a few studies focus on the preparation and drug release of electrospun fibers prepared from biopolymers and Amox, in order to use them as drug delivery systems. These studies include the optimization of the preparation process, the modification of properties, the control of drug release, and microbiological effects [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. Valarezo et al [ 20 , 21 ], for example, prepared fibers from poly(lactic acid) (PLA)/polycaprolactone (PCL) blends containing Amox and could control the rate of drug release by adjusting the ratio of the two polymers.…”