Table 1.

Advantages and limitations of some biodegradable nanoparticles.

Biodegradable Nanoparticles		Advantages	Limitations
General		Biocompatibility Low immunogenicity Slow and controlled release of the cargo Targeted delivery Enhanced therapeutic effects Decreased side-effects and cytotoxicity Modifiable size and surface to improve drug release profile and targeting efficiency	Instable if not modified High cost of particle production Difficult to synthesize particles that are homogeneous in shape and size Relatively low drug encapsulation efficiency Difficulty in large scale production and sterilization
Polymer-based	PLA micelles	Hydrophobicity useful for carrying low soluble drugs Easily modifiable physical and chemical properties to obtain desirable pharmacokinetic and biodegradable properties	Non-specific uptake by the reticuloendothelial systems Low drug loading capacity Low encapsulation efficiency Particle size-dependent immunotoxicity Easily affected degradation rate
	PLGA micelles	Wide range of erosion times Modifiable mechanical properties Degradation rate can be changed by adjusting the ratio of PLA:PGA and their molecular weights	The acidic nature of PLGA monomers are not suitable for certain drugs and bioactive molecules Difficult to achieve optimal drug release profile non-linear, dose-dependent, and easily altered biodistribution and pharmacokinetics
	PCL nanoparticles	Degradation does not produce acidic byproducts Slow degradation rate, ideal for long-term implantation device Versatile mechanical properties	Hydrophobicity that limits its production
	Chitosan nanoparticles	Good absorbability, permeability, and moisture retention Easily degradable Low toxicity	Very sensitive to environmental temperature Degradation rate affected by environmental pH Poor long-term stability
	Dendrimers	High degree of branching and polyvalency, with very high surface-to-volume ratio, enabling high drug carrying efficiency Capable of carrying drugs with poor solubility High water solubility Useful as MRI imaging agent	Cytotoxicity may occur during the interactions with cell membrane depending on the charge and modifications made on the surface of the dendrimer
Lipid-based	Liposomes	Self-assembly, enabling easy drug loading High loading efficiency Protect encapsulated drugs from early inactivation, degradation and dilution in the circulation Can be formulated into different forms for various routes of administration Easily functionalized with surface modification	Fast clearance rate Low stability Complex production method