Prior art — US Patent 4151844

Here is an analysis of the most relevant prior art cited in US Patent 4151844, based on the provided patent text.

The present invention (US4151844) relates to a method and apparatus for separating whole blood into its components, specifically featuring automatic monitoring of one component (e.g., white blood cells/buffy coat) using an optical sensing device and automatic adjustment of the withdrawal rates of other components (red blood cells and plasma) to maintain a desired composition [Abstract, Description: "Summary of the Invention"]. This automation aims to overcome the prior art requirement for constant operator attention and manual adjustment of pump speeds [Description: "Background of the Invention", "Description of the Prior Art"].

The following patent citations are listed as prior art for US4151844:

Prior Art Analysis:

1. US2876769A

Full Citation: US2876769A, Cordova Jose Juan, "Apparatus for oxygenating, centrifuging and changing the temperature of blood"
Publication/Filing Date: Priority date: 1955-10-11, Publication date: 1959-03-10
Brief Description: This patent describes an apparatus for oxygenating, centrifuging, and changing the temperature of blood. The title suggests a focus on a multi-functional device for blood processing, including centrifugation.
Potentially Anticipates Claims (35 U.S.C. § 102):
- Claims 1, 7 (General Method/Apparatus for Blood Separation): This patent potentially anticipates the general concept of centrifuging blood to separate components (Claim 1: "centrifuging the blood to separate same into at least three components thereof"; Claim 7: "An apparatus for separating whole blood into at least three blood components thereof comprising: ... a centrifuge device"). However, it does not appear to anticipate the automatic monitoring and adjustment features central to US4151844 without further details of its internal control mechanisms. A full anticipation assessment would require reviewing the complete patent text of US2876769A.

2. US3489145A

Full Citation: US3489145A, Surgeon General Of The Public, "Method and apparatus for continuous separation of blood in vivo"
Publication/Filing Date: Priority date: 1966-08-08, Publication date: 1970-01-13
Brief Description: This patent describes a method and apparatus for continuous separation of blood in vivo. The term "continuous separation" suggests a flow-through centrifugation system, which is a foundational aspect of US4151844.
Potentially Anticipates Claims (35 U.S.C. § 102):
- Claims 1, 7 (Continuous Blood Separation and Component Withdrawal): The concept of continuously separating blood and withdrawing components (Claim 1: "withdrawing each of the components during the centrifugation thereof"; Claim 7: "first withdrawing means...second withdrawing means...third withdrawing means for withdrawing a third blood component") could be generally anticipated. However, the specific automatic optical sensing and proportional adjustment claimed in US4151844 (Claims 3, 4, 5, 6, 8-20) are not evident from the title or general description. A full anticipation assessment would require reviewing the complete patent text of US3489145A.

3. US3519201A

Full Citation: US3519201A, Us Health Education & Welfare, "Seal means for blood separator and the like"
Publication/Filing Date: Priority date: 1968-05-07, Publication date: 1970-07-07
Brief Description: This patent focuses on "Seal means for blood separator and the like," suggesting a technical solution for fluid integrity within blood processing devices, possibly for rotating components like centrifuges.
Potentially Anticipates Claims (35 U.S.C. § 102):
- This patent, based on its title, likely addresses a mechanical detail (seal means) rather than the overall control method or apparatus for automatic component collection. It is less likely to anticipate the method or control system claims (Claims 1-6, 9-20) of US4151844, though the underlying apparatus (Claim 7) might incorporate such sealing mechanisms. No direct anticipation of the unique features of US4151844 is apparent from the title. A full anticipation assessment would require reviewing the complete patent text of US3519201A.

4. US3655123A

Full Citation: US3655123A, Us Health Education & Welfare, "Continuous flow blood separator"
Publication/Filing Date: Priority date: 1966-08-08, Publication date: 1972-04-11
Brief Description: This patent describes a "Continuous flow blood separator," reinforcing the concept of continuously processing blood to separate its components.
Potentially Anticipates Claims (35 U.S.C. § 102):
- Claims 1, 7 (Continuous Blood Separation Apparatus): Similar to US3489145A, this patent likely anticipates the general elements of a continuous flow blood separation apparatus. However, there is no indication from the title alone that it includes the automatic optical sensing and adjustment of withdrawal rates as taught by US4151844 (Claims 3, 4, 5, 6, 8-20). A full anticipation assessment would require reviewing the complete patent text of US3655123A.

5. US3802432A

Full Citation: US3802432A, I Djerassi, "Apparatus for filtration-leukopheresis for separation and concentration of human granulocytes"
Publication/Filing Date: Priority date: 1972-05-18, Publication date: 1974-04-09
Brief Description: This patent describes an apparatus for "filtration-leukopheresis" for the separation and concentration of human granulocytes (a type of white blood cell). This indicates prior art in separating specific blood components, particularly white blood cells.
Potentially Anticipates Claims (35 U.S.C. § 102):
- Claim 2 (Separation of White Blood Cells/Buffy Coat): This patent directly addresses the separation and concentration of white blood cells (granulocytes), which aligns with Claim 2 of US4151844 where the desired component is white blood cells/buffy coat. While it deals with collecting white blood cells, the title suggests a "filtration-leukopheresis" approach, which is different from the centrifugation and optical density sensing mechanism of US4151844. Thus, the specific method of automatic optical sensing and adjustment of US4151844 (Claims 3, 4, 5, 6, 8-20) is unlikely to be anticipated. A full anticipation assessment would require reviewing the complete patent text of US3802432A.

6. US3812482A

Full Citation: US3812482A, Primary Childrens Hospital, "Air emboli detector"
Publication/Filing Date: Priority date: 1973-02-26, Publication date: 1974-05-21
Brief Description: This patent describes an "Air emboli detector." This suggests a safety or monitoring device for detecting air bubbles in fluid systems, which is relevant to extracorporeal blood circuits. US4151844 mentions "suitable low and high pressure sensors are provided in the tubing 21 to sense high and low pressure conditions indicating a leak... or an occluded vein" [Description: "The first tubing 21"]. While related to system safety, it's not directly about blood component separation control.
Potentially Anticipates Claims (35 U.S.C. § 102):
- This patent primarily addresses a safety feature (air emboli detection) which is distinct from the core inventive concept of US4151844 concerning automatic optical density-based control of blood component withdrawal rates. No direct anticipation of the claims of US4151844 related to automatic separation control is apparent from the title. A full anticipation assessment would require reviewing the complete patent text of US3812482A.

7. US3892236A

Full Citation: US3892236A, Isaac Djerassi, "Apparatus for filtration-leukopheresis for separation and concentration of human granulocytes"
Publication/Filing Date: Priority date: 1973-04-02, Publication date: 1975-07-01
Brief Description: This patent is identical in title and inventor to US3802432A, describing an "Apparatus for filtration-leukopheresis for separation and concentration of human granulocytes." It likely represents a continuation or related work to US3802432A.
Potentially Anticipates Claims (35 U.S.C. § 102):
- Claim 2 (Separation of White Blood Cells/Buffy Coat): Similar to US3802432A, this patent directly addresses the separation and concentration of white blood cells. As noted previously, while it deals with collecting white blood cells, the "filtration-leukopheresis" method is distinct from the centrifugation and optical density sensing and automated control of US4151844. Therefore, the specific automatic monitoring and adjustment features of US4151844 (Claims 3, 4, 5, 6, 8-20) are unlikely to be anticipated. A full anticipation assessment would require reviewing the complete patent text of US3892236A.

8. US4086924A

Full Citation: US4086924A, Haemonetics Corporation, "Plasmapheresis apparatus"
Publication/Filing Date: Priority date: 1976-10-06, Publication date: 1978-05-02
Brief Description: This patent describes a "Plasmapheresis apparatus." Plasmapheresis involves the separation of plasma from whole blood, a key step in blood component separation, and often involves centrifugation.
Potentially Anticipates Claims (35 U.S.C. § 102):
- Claims 1, 7 (Blood Component Separation, particularly Plasma): This patent clearly falls within the field of blood component separation, specifically focusing on plasma. It likely anticipates the general apparatus and method for separating blood into components, including plasma, as outlined in Claims 1 and 7. Given the context of US4151844's problem statement (operator adjustment for buffy coat purity), it is possible that advanced plasmapheresis apparatus like this one might have some form of automated control, but the specific optical density sensing of the buffy coat and the responsive, differential adjustment of red blood cell and plasma pump speeds (Claims 3, 4, 5, 6, 8-20) is not apparent from the title. US4151844 distinguishes itself by focusing on the automatic collection of a specific component (white blood cells/buffy coat) with minimal contamination through optical feedback and differential pump control. A full anticipation assessment would require reviewing the complete patent text of US4086924A.

Conclusion on Anticipation:

Based solely on the titles and brief descriptions available in the US4151844 patent document, the cited prior art generally anticipates the broad concepts of:

Centrifugal blood separation (US2876769A, US3489145A, US3655123A, US4086924A).
Continuous flow blood processing (US3489145A, US3655123A).
Separation and collection of specific blood components, including white blood cells (US3802432A, US3892236A) and plasma (US4086924A).

However, the core inventive contribution of US4151844, as explicitly stated in its summary and description, lies in the automatic optical monitoring of a collected blood component (like the buffy coat) and the responsive, differential, and graded adjustment of withdrawal rates of the other components to maintain a desired composition. This specific combination of optical sensing, determination of density and its trend (increasing/decreasing), and the nuanced control of multiple pumps in an inverse relationship (as detailed in Claims 3, 4, 5, 6, 9-20) does not appear to be directly anticipated by the titles or generalized descriptions of the cited prior art. The prior art descriptions provided within US4151844 indicate a problem with existing systems requiring constant manual operator intervention to achieve desired purity, which is precisely what US4151844 claims to overcome with its automated control system.

A definitive determination of anticipation under 35 U.S.C. § 102 for each claim would necessitate a thorough review of the full text of each cited prior art patent and a detailed element-by-element comparison.