TABLE 3.

Biohybrid MNRs for motile-targeting drug delivery.

Energy sources		Representative examples	Experimental environment	Motion behavior	Loaded cargo/therapeutic drugs	Biomedical application	Ref.
Living cells		Sperm hybrid micromotors	In vitro	Average speed: 41 ± 10 μm/s	DOX hydrochloride	Drug delivery (e.g., cancer, diseases in the female reproductive system)	Xu et al. (2018)
		SHC hybrid sperm micromotors	In vitro	Average speed: 76 ± 17 μm/s in blood	Heparin	Diseases in the circulatory system (e.g., blood clot)	Xu et al. (2020a)
		Human-sperm-based hybrid micromotors	In vitro	N.A.	DOX and CPT	Gynecologic diseases (e.g., cervical cancer, ovarian cancer)	Xu et al. (2020b)
		Neutrobots	In vitro	Maximum speed: 16.4 μm/s	Paclitaxel	Drug delivery	Zhang H et al. (2021)
			In vitro
Micro-organisms	Microalga	Microalga-powered biohybrid microswimmers	In vitro	Average speed: 156.13 ± 9.66 μm/s	FITC labeled dextran	Drug delivery	Yasa et al. (2018)
	E. coli	Soft erythrocyte-based bacterial microswimmers	In vitro	Average speed: 10.2 ± 3.5 μm/s	DOX and superparamagnetic iron oxide nanoparticle	Drug delivery	Alapan et al. (2018)
		TDNPP-coated E. coli	In vitro	N.A.	TDNPPs	Photodynamic cancer therapy Intracellular cargo (e.g., protein) delivery	Wu M et al. (2019)
		Engineered probiotics	In vitro	N.A.	PD-L1 and CTLA-4 antagonists	Immunotherapy	Canale et al. (2021)
			In vivo
		Magnetic-sensing E. coli	In vitro	Average speed: 5µm/min ±2 μm/min	N.A.	Potential for drug delivery	Aubry et al. (2020)