*A Microfluidic Device as a Drug Carrier DOI: http://dx.doi.org/10.5772/intechopen.102052*

Polymer/PSi microcomposite. The manufactured microcomposites were confirmed to have a monodisperse size distribution, multistage pH-response, a particular ratiometric controllable loading extent closer to the concurrently loaded drug molecules, and tailored-made drug release kinetics. This attractive microcomposite technology prevents payloads from being released at low pH values and promotes medicine delivery at higher pH values, and could be used to prevent and treat colon and rectum cancers in the future. Overall, the pH-responsive polymer/PSi-based fully micro composite [63] might be employed as a common platform for combining drug delivery systems for multiple drug compounds [61].

The preparation of monodisperse microparticles of a biodegradable polymer was carried out using an instrument for focusing a microfluidic flow for controlled drug delivery. The manufacture of monodisperse microparticles containing a drug from biodegradable polymers, the use of devices for focusing a microfluidic flow, and the drug delivery properties of these particles have been described [64]. The particle size ranges from 10 to 50 mm. These particles are practically monodispersed with a polydispersity index of 3.9% [65]. Bupivacaine (amphiphilic) is included in a biodegradable debris matrix to characterize the formulation as a model drug [65–67]. The kinetic evaluation suggests that drug release from these monodisperse microparticles is slower than conventional strategies with the same average size, but reveals a larger particle size distribution and, more importantly, a significant reduction in a primary burst than that found with traditional methods, as shown in **Figure 1** [65, 67]. The difference in the preliminary kinetics of drug release is explained by the even distribution of the drug within the particles created using microfluidic strategies. These results demonstrated the application of microfluidic flow-focusing to homogeneous particle system technology for drug delivery [65].

Recently, thermosensitive liposome-controlled release using a disposable microfluidic instrument was developed, with the release of the encapsulated drug from the liposome nanocarrier expected to increase local drug delivery while reducing the toxic effects of increased temperature. High Intensity Focused Ultrasound (HIFU) [68–71], microfluidic devices with micro-HIFU (MHIFU), allow simulation of the bulky HIFU transmission instrument with lower energy consumption and to control of the release of the investigated low-temperature liposomes (LTSL) [52, 72]. In addition, when transitioning to a local temperature of 41–43°C, the structure changes from a gel to a liquid crystal phase, and the encapsulated drug is released by an external hyperthermia source (such as a microwave or infrared radiation laser). The

**Figure 1.**

*A strategy for producing dispersed drugs using microfluidic techniques.*

lipid membrane structure of low temperature-sensitive liposomes (LTSL) [73]. The era of microfluidics may also provide a promising method for studying ultrasound and the complex dynamics of organisms at the ultramicro level [74]. The main task of improving polymer nanoparticles for many procedures is to specifically engineer preferred physicochemical properties in a repeatable manner [67].

Microfluid self-assembly [9, 75] of polymer nanoparticles with adjustable compactness for controlled drug delivery is predominantly self-assembled hydrophobically modified chitosan (HMC) biopolymer-based nanos. The particle compactness can be determined by adjustable high-speed blending with hydrodynamic flow focusing on microfluidic channels. It has been demonstrated that the self-organizing properties of the chain can be controlled by optimizing the size and compactness of the species, as well as the more restricted particle size distribution, through various flow rates as well as the hydrophobicity of the chitosan chain of nanoparticles [67, 76]. The particle size of the formulation components increased with increasing blending time, while the chitosan produced smaller and more compact nanoparticles with a much smaller variety of aggregated chains and a higher degree of hydrophobicity.

The scientists found that nanoparticles with nearly equal forms of hydrophobic adhesion were formed by blending the two liquids. The scientists found that the lack of affinity for the aqueous medium and the blending times longer than the time of aggregation hindered the formation of nanoparticles with different forms of hydrophobic adhesion.

Moreover, researchers investigating the effectiveness of microfluidics for assembling HMCs and enclosing paclitaxel, a typical anticancer medication, showed that it has a significantly greater encapsulation efficiency and overall quality than the traditional bulk technique. The impact of the components of the synthetic medication on the parameters of the release of paclitaxel from nanoparticles was investigated. [31]. The predicted 50% paclitaxel diffusion coefficient upon drug release meant sustainability in controlling drug release for nanoparticle compactness and superior results compared to traditional bulk blending methods [31, 77]. These results show an excess of microfluidic methods for specific bottom-up control of the physicochemical properties of polymer nanoparticles in many programs [78], including controlled drug delivery [31, 67, 77].

An electrokinetic microfluidic device for rapid, low-power drug delivery in self-sustaining microcontrollers evolved as a low-power, powerful, electrically active

## **Figure 2.**

*Fluid-handling systems for the microfabrication of smart materials, including pumps, valves, and flow channels.*
