Microorganism concentration process
A process for capturing or concentrating microorganisms for detection or assay comprises (a) providing a concentration agent that comprises an amorphous metal silicate and that has a surface composition having a metal atom to silicon atom ratio of less than or equal to about 0.5, as determined by X-ray photoelectron spectroscopy (XPS); (b) providing a sample comprising at least one microorganism strain; and (c) contacting the concentration agent with the sample such that at least a portion of the at least one microorganism strain is bound to or captured by the concentration agent.
1. A process comprising:
(a) providing an inorganic concentration agent that comprises an amorphous, spheroidized metal silicate formed from melted or softened metal silicate feed particles and that has a surface composition having a metal atom to silicon atom ratio of less than or equal to 0.5, as determined by X-ray photoelectron spectroscopy (XPS), wherein said metal is selected from magnesium, calcium, zinc, aluminum, iron, titanium, and combinations thereof;
(b) providing a sample comprising at least one microorganism strain;
(c) contacting said concentration agent with said sample such that at least a portion of said at least one microorganism strain is bound to or captured by said inorganic concentration agent;
(d) segregating the resulting microorganism-bound inorganic concentration agent, wherein said segregating is affected by a method selected from gravitational settling, centrifugation, and combinations thereof; and
(e) separating the resulting segregated microorganism-bound inorganic concentration agent from said sample.
2. The process of claim 1 , wherein said inorganic concentration agent is a particulate concentration agent.
3. The process of claim 1 , wherein said surface composition has a metal atom to silicon atom ratio of less than or equal to 0.4.
4. The process of claim 1 , wherein said inorganic concentration agent has a negative zeta potential at a pH of 7.
5. The process of claim 1 , wherein said metal is magnesium.
6. The process of claim 1 , wherein said inorganic concentration agent comprises an amorphous metal silicate in at least partially fused particulate form.
7. The process of claim 1 , wherein said inorganic concentration agent is amorphous, spheroidized magnesium silicate.
8. The process of claim 1 , wherein said sample is in the form of a fluid.
9. The process of claim 1 , wherein said microorganism strain is selected from strains of bacteria, fungi, yeasts, protozoans, viruses, bacterial endospores, and combinations thereof.
10. The process of claim 1 , wherein said contacting is carried out by mixing said inorganic concentration agent and said sample.
11. The process of claim 1 , wherein said process further comprises detecting the presence of at least one bound microorganism strain.
12. The process of claim 11 , wherein said detecting is carried out by a method selected from culture-based methods, microscopy and other imaging methods, genetic detection methods, immunologic detection methods, bioluminescence-based detection methods, and combinations thereof.