Table 1.

Reports of improved ALA delivery using nanotechnology and nanomedicine

Nanoparticle	Structure	Type of Experiment/Animal Model	Advantages	Clinical Application	Ref
Liposomes		In vitro and in vivo in rats	Compatible with lipid bilayer structure May employ surface ligands to attach to tissue	Drug delivery to treat: Skin cancer, Acne, Wrinkles	[17, 24, 25]
Ethosomes		Mice	Greater penetration ability than liposomes, smaller particle size	Skin cancer treatment	[21, 26]
Niosomes		Excised human skin	80 and 40% increased permeation of drug and 50 to 100% of the drug retained into the skin when compared to aqueous drug solution	Therapeutic treatment for skin malignancies, hidradenitis suppurativa	[27]
Polymeric nanoparticles		HeLa cancer cells Ex vivo skin transport	10× higher transdermal transport Increased cell killing by PDT		[28–30]
Mesoporous Silica		Mice	Bypasses the lipophilic barrier to directly enter into cancer cells Exhibited high photocytotoxicity to cancer cells in vitro		[31]
Conjugated Gold Particles		Human chronic myeloid leukemia K562 cells, biodistribution in rabbits Human fibroblast and A431 cells	Used to circumvent multidrug resistance mechanisms Singlet oxygen generation by localized surface plasmon resonance of GNPs	Early diagnosis and therapy of atherosclerosis	[32–36]
Fullerene Nanoparticles		Mice	No detectable toxicity Compared to ALA, significant improvement in antitumor efficacy		[37]
ALA Dendrimers		LM3 mammary carcinoma cells, PAM 212 murine keratinocyte and A431 human epidermoid carcinoma cell lines	More efficient at low concentrations compared to equimolar ALA for porphyrin production, most lipophilic, minimal dark toxicity, high drug payload		[38–40]
Carbon Nanotubes		MGC-803 tumor cells	Increased PPIX formation Strong optical absorbance in NIR (near-infrared) light		[41]