**3.2 Red cell membrane coating techniques on nanoparticle and solid surface**

Cell membrane coating technology comes from phospholipid manipulation technique which forms liposome and solid-supported lipid bilayer because the phospholipids are the main component of cell membrane. Although the phospholipid manipulation technique was developed quite a while ago, cell membrane coating techniques on nanoparticles were first reported in 2011 (**Figure 5**) [7]. Researchers prepared RCM-coated nanoparticles by RCM vesicle-nanoparticle fusion [25, 26]. Specifically, the extracted cell membrane was adequately diluted (membrane extraction was described in Section 3.1.). For the membrane vesicle derivation, outer forces are applied to the diluted membrane. Sonicating the membrane is the easiest way to make membrane vesicle, but it is hard to regulate the size of the vesicle. Alternatively, extrusion methods can control the size of the membrane vesicle by porous polymer membrane with various pore sizes. Next, membrane coating onto nanoparticles is conducted with the same procedure to

#### **Figure 5.**

*The schematic illustration of the preparation of RBC membrane-coated polymeric nanoparticles [7]. RBCs, red blood cell; polymeric NP, polymeric nanoparticle such as poly(lactic-co-glycolic acid) (PLGA) nanoparticle.*

**143**

*Application of Red Cell Membrane in Nanobiotechnology DOI: http://dx.doi.org/10.5772/intechopen.84274*

vesicle fusion.

**Figure 6.**

by high thermal energy [29].

*Fusion of a lipid vesicle on solid surface [27].*

**biosensors**

RCM [9].

vesicle formation (i.e., sonication or extrusion). In detail, the prepared membrane vesicles are mixed with nanoparticles. Then the sonication or extrusion of the mixture can lead to the coating of membrane onto the nanoparticles by the principle of

The cell membrane coating on solid surface is similar to that on nanoparticles described above. The coating procedure is based on vesicle fusion method (**Figure 6**) [27]. The only different procedure for solid surface coating is that thermal energy is employed instead of mechanical energy (i.e., sonication or extrusion) [9, 28]. Specifically, the cell membrane vesicles with adequate concentration were placed on solid surface and incubated for 45 min at 50°C. The thermal energy induces the membrane vesicle to collide and fuse onto the solid surface. It is noted that the temperature for vesicle fusion should be lower than the denaturation temperature of proteins to avoid the deactivation or misfolding

**4. The applications of red cell membrane in drug delivery systems and** 

In drug delivery system related with nanomaterial, long-term circulation of nanoparticles in vivo is one of the most important characteristics because various immune responses clear the foreign molecules in the body and blood [31]. Especially, MPS and CS are major immune systems eliminating drug delivery carriers. Conventionally, to evade the immune systems, the drug carriers are functionalized with polyethylene glycol (PEG) which slows clearance in blood and avoids non-specific binding of blood proteins [32, 33]. In our body, however, there is an anti-PEG immunological response which removes PEGylated nanoparticles [34]. By contrast, the RCM-coated nanoparticles showed prolonged circulation in blood. The result is exactly attributed to membrane receptors and cell adhesion molecules,

**4.1 Drug delivery with red cell membrane-coated nanoparticles**

RCM-coated nanoparticles, also called RC-camouflaged nanoparticles, have been developed for drug delivery system since they were devised by Zhang and his group in 2011. It was found that immune evasive properties of RCM-coated nanoparticles are superior to conventional nanoparticles. The membrane proteins confer the advantages of the immune avoidance properties described in Section 2. RCM coating has been applied to various core nanoparticles such as gold, poly(lactic-coglycolic acid) (PLGA), silica, and iron oxide nanoparticles [30]. Also, RCM can be utilized as permselective filter for glucose biosensor taking advantage of GLUT on

*Application of Red Cell Membrane in Nanobiotechnology DOI: http://dx.doi.org/10.5772/intechopen.84274*

**Figure 6.** *Fusion of a lipid vesicle on solid surface [27].*

*Erythrocyte*

(EDTA)

*Factor IIa, thrombin.*

*factor Xa, serine endopeptidase.*

*a*

*b*

**Table 2.**

microscope. To remove the hemoglobin, hemolyzed solution is centrifuged and washed. Then the RCM is collected with light pink pellet. The resulting RCM

**Anticoagulant Usage Mechanism**

transfusion

Citrate Coagulation assays, blood

Heparin Cytogenetic studies Activate antithrombin III which

molecular genetic studies, complete blood counts

deactivates serum clotting factors

Bind to calcium reversibly (not as

Strongly bind to calcium irreversibly.

IIa and b Xa)

The absence of calcium

(factors a

strong as EDTA)

**3.2 Red cell membrane coating techniques on nanoparticle and solid surface**

Cell membrane coating technology comes from phospholipid manipulation technique which forms liposome and solid-supported lipid bilayer because the phospholipids are the main component of cell membrane. Although the phospholipid manipulation technique was developed quite a while ago, cell membrane coating techniques on nanoparticles were first reported in 2011 (**Figure 5**) [7]. Researchers prepared RCM-coated nanoparticles by RCM vesicle-nanoparticle fusion [25, 26]. Specifically, the extracted cell membrane was adequately diluted (membrane extraction was described in Section 3.1.). For the membrane vesicle derivation, outer forces are applied to the diluted membrane. Sonicating the membrane is the easiest way to make membrane vesicle, but it is hard to regulate the size of the vesicle. Alternatively, extrusion methods can control the size of the membrane vesicle by porous polymer membrane with various pore sizes. Next, membrane coating onto nanoparticles is conducted with the same procedure to

*The schematic illustration of the preparation of RBC membrane-coated polymeric nanoparticles [7]. RBCs, red blood cell; polymeric NP, polymeric nanoparticle such as poly(lactic-co-glycolic acid) (PLGA) nanoparticle.*

concentrate is stored in −70°C before use.

Ethylenediaminetetraacetic acid

*Vacutainers with various anticoagulants.*

**142**

**Figure 5.**

vesicle formation (i.e., sonication or extrusion). In detail, the prepared membrane vesicles are mixed with nanoparticles. Then the sonication or extrusion of the mixture can lead to the coating of membrane onto the nanoparticles by the principle of vesicle fusion.

The cell membrane coating on solid surface is similar to that on nanoparticles described above. The coating procedure is based on vesicle fusion method (**Figure 6**) [27]. The only different procedure for solid surface coating is that thermal energy is employed instead of mechanical energy (i.e., sonication or extrusion) [9, 28]. Specifically, the cell membrane vesicles with adequate concentration were placed on solid surface and incubated for 45 min at 50°C. The thermal energy induces the membrane vesicle to collide and fuse onto the solid surface. It is noted that the temperature for vesicle fusion should be lower than the denaturation temperature of proteins to avoid the deactivation or misfolding by high thermal energy [29].
