Table 2.

Crystal carrier media for serial sample loading.

Media	Advantages	Disadvantages	References
Oil	general versatility	higher background scattering
Nuclear grade grease	lower background scattering among grease matrices	salt-like impurities in grease	this study
Synthetic grease	higher versatility	gives a stronger diffraction ring at ~4.8 Å	26
Mineral-oil based grease	higher versatility	a larger diameter sample column	21
Vaseline (petroleum jelly)	a smaller diameter sample column (~40 μm)	gives stronger diffraction rings at 4.2 and 3.8 Å	22
Hydrogel	lower background scattering	damage to crystals by osmotic shock
Hydroxyethyl cellulose	simple preparation	adhesive	this study
Hyaluronic acid	simple preparation	strongly adhesive, expensive	26
Agarose	compatible with proteins	requires heat treatment at temperatures higher than 85 °C as a pre-preparation	23
Other
LCP (e.g., monoolein)	applicable to soluble and membrane proteins	higher background scattering, but lower than grease in the resolution range of 4–5 Å	20, 22, 23