Fabrication of Polymeric Microparticles by Electrospray: The Impact of Experimental Parameters

Abstract

Microparticles (MPs) with controlled morphologies and sizes have been investigated by several researchers due to their importance in pharmaceutical, ceramic, cosmetic, and food industries to just name a few. In particular, the electrospray (ES) technique has been shown to be a viable alternative for the development of single particles with different dimensions, multiple layers, and varied morphologies. In order to adjust these properties, it is necessary to optimize different experimental parameters, such as polymer solvent, voltage, flow rate (FR), type of collectors, and distance between the collector and needle tip, which will all be highlighted in this review. Moreover, the influence and contributions of each of these parameters on the design and fabrication of polymeric MPs are described. In addition, the most common configurations of ES systems for this purpose are discussed, for instance, the main configuration of an ES system with monoaxial, coaxial, triaxial, and multi-capillary delivery. Finally, the main types of collectors employed, types of synthesized MPs and their applications specifically in the pharmaceutical and biomedical fields will be emphasized. To date, ES is a promising and versatile technology with numerous excellent applications in the pharmaceutical and biomaterials field and such MPs generated should be employed for the improved treatment of cancer, healing of bone, and other persistent medical problems.

Determination of the Operational Parameters for the Manufacturing of Spherical PVP Particles via Electrospray

“…One can see that the increase of polymer concentration significantly affects the conical shape and velocity of the PVP solution. This agrees well with the experimental finding and previous studies [ 12 , 58 , 59 ]. Additionally, to the evolution of meniscus shape we present the velocity plot along the longitudinal axis at 60 ms for both concentrations of PVP (see Figure 9 ).…”

PLGA-based biodegradable microspheres in drug delivery: recent advances in research and application

“…Electrospray is generally composed of a high-voltage power supply, syringe pump, metal nozzle, and collection substrate (Nguyen et al, 2016 ; Morais et al, 2020 ) ( Figure 5 ). The polymer solution is injected into the capillary nozzle by a syringe pump.…”

“…At this time, a certain voltage is applied between the nozzle and the collecting substrate to generate a high-pressure difference (Jafari-Nodoushan et al, 2015 ). The ejected solution forms a special ‘Taylor cone’ at the nozzle to form droplets and further atomize into particles, which then move to the collection substrate with opposite charges (Malik et al, 2016 ; Morais et al, 2020 ). Generally, the size of the formed particles is between tens of nanometers to hundreds of microns and has a smaller particle size distribution (Nguyen et al, 2016 ; Morais et al, 2020 ).…”

“…The ejected solution forms a special ‘Taylor cone’ at the nozzle to form droplets and further atomize into particles, which then move to the collection substrate with opposite charges (Malik et al, 2016 ; Morais et al, 2020 ). Generally, the size of the formed particles is between tens of nanometers to hundreds of microns and has a smaller particle size distribution (Nguyen et al, 2016 ; Morais et al, 2020 ). Common ES systems include mono-Coaxial ES (MES), coaxial ES (CES), and multiplexed ES (MCES).…”

“…The outer layer solution can wrap the inner layer solution to produce particles with a core-shell structure (Han et al, 2016 ). The system setup of MCES is composed of several parallel capillary tubes, which is helpful for the improvement of microsphere yield and the realization of large-scale production (Pathak et al, 2016 ; Morais et al, 2020 ). Microspheres prepared by electrospray technology can produce particles with different sizes and morphologies by regulating different experimental parameters, such as voltage and velocity (Lai et al, 2017 ; Wang et al, 2019 ; Gupta & Panigrahi, 2020 ).…”