TABLE 4.

Overview of the use of non-polymeric materials for bacteriophage embedding.

Envisioned application	Material and construct	Embedded phage	Relevant results				Reference
			Study type	Manufacturing process	Phage release / Protective properties	Antimicrobial effects
Intercellular delivery of bacteriophages	Biomimetic HAP nanocrystals	S. rissen phage SR φ1	In vitro	Phage and HA nanoparticles were mixed together, and phages adsorbed on the HA material. 107 PFU/mg of HA nanoparticles were adsorbed after 24 h.	Phage adsorbed on HA nanocrystals show no reduction of lytic activity after 6 weeks of storage at 4°C. Adsorbed phage shows no inactivation due to acidic environment.	A 3-log reduction of S. rissen was observed when incubated with HA-SR φ1.	Fulgione et al., 2019
Delivery of phage within difficult to penetrate biofilms	Chitosan coated iron oxide non-colloidal nanoparticles for phage grafting	E. coli phage C3000 and P. aeruginosa phage PA01	In vitro	Phage is conjugated to the chitosan coated iron oxide nanoparticle though carbodiimide chemistry.	No phage release, particles possess contact killing though surface functionalized phages.	Particles were able to penetrate biofilms better under magnetic fields and reduce the quantity of biofilm with 90% (compared to 35% for free phage).	Li et al., 2017
Prophylactic use in orthopedic reconstruction surgery	Microporous pelleted CaP granules	E. coli phage λ vir	In vitro	Phage was loaded by allowing adsorption at 4°C for 24 h.	The pellets were washed for 3 h prior to testing, resulting in a 2-log reduction of phage load, indicating strong burst-like release properties. However, pellets washed for 6 days could still inhibit bacterial growth in a zone of inhibition experiment.	Optical density measurements show a reduction when phage loaded CaP materials were introduced to the culture. An increase of porosity of the sintered materials results in higher phage load and a lower optical density of the bacterial culture.	Meurice et al., 2012
Prophylactic use in orthopedic reconstruction surgery	Macro porous CaCO3 and HAP scaffold.	E. coli phage λ vir	In vitro	Phage was loaded by allowing adsorption at 4°C for 24 h.	Not assessed	OD600 measurements indicate antimicrobial effects after 90 min of coincubation. Increased porosity	Colom et al., 2015

Abbreviations – CaP: Calcium phosphate; HA: Hydroxyapatite; OD₆₀₀: Optical density at a wavelength of 600 nm.