Table 1.

Comparison of drug loading approaches

Method	Advantages	Disadvantages
Passive Loading	Simple method	Drug can alter cell properties
	Uses concentration gradient	Passive unloading
		Not suitable for hydrophobic drugs
Receptor mediated loading	Direct targeting toward receptor	May require use of nanoparticles
		Expensive ligands
Physical loading	Tried and tested methods	Invasive
		Impacts cell viability
Liposome-mediated Loading	Well researched	Expensive method when scaled up
	Can be enhanced by targeting receptors/surface modification
	Protects the delivered drug
EV vector loading	Naïve MSC EVs are therapeutic	Not fully characterised
	Easily isolated	Poor targeting in some diseases
	Proven to carry cargo from parent cell	Can be difficult to obtain large numbers