Wednesday, 29 October 2014

Low Cost High Efficiency Hemodialysis Fibre

Indian Patent Filling No.: 754/KOL/2014b dated 11-07-2014

[Updated: Award won:
1. National Award for Technology Innovation in the category of Polymer in public healthcare 2015
2. DST Lockheed Martin India Innovation Growth Program Award 2015 (video at the end of this post)]

Haemodialysis is a very expensive treatment procedure, administered to people suffering from end stage renal disease (ESRD). The crux of the problem lies in replacing the faltered kidney function with a cartridge driven mechanism to purify blood in an extracorporeal circuit. This cartridge has 7000 to 15,000 hollow fibres of 180-220 microns inner diameter and 15-35 micron thickness, thereby yielding a surface area of 1 m-square  or more for filtration. The focus of the problem lies in the spinning of fibres of specific dimensions, which is also a proprietary technology of the manufacturing houses of such fibres. Usually, the spinning of fibres is carried out with spinerrets, which are thousands of dollars in terms of their cost. These cartridges are generally German, Japanese or Korean imports to India, and cost anything around 1500-2500 INR per cartridge. A person suffering from ESRD requires at least 3 dialysis sessions per week. Ideally a fresh new cartridge is desired for every session, but for a developing economy like India, where reuse is indeed the name of the game, one cartridge is used for two or three sessions. This has a twofold negative effect. One, it is extremely unhygienic for a single cartridge to put to use for multiple sessions. Secondly, fouling of membrane reduces the performance of the cartridge, thereby prolonging the receding sessions. Prolonged dialysis sessions challenge the patients’ capability to withstand the ordeal of the process.

To address this, IIT Kharagpur research team comprising of Professor S. De and Mr. Aniban Roy with able support from Dr. Liyod Vincent, Senior Consultant Nephrologist and Clinical Director Dialysis Services of Narayana Hrudayalaya Hospital, and Dr. Shyam Vasudeva Rao, President and CTO, Forus Health Pvt. Ltd have come up with a novel technology titled, "Low cost spinning and fabrication of high efficiency (HE) haemodialysis cartidge." Its Indian Patent is filed on 11th July, 2014 and international filing process is underway.
Members of the inventing explained us the USP of this technology. This patent introduces, for the first time, a technology to spin high efficiency (HE) dialysis grade hollow fibres (molecular weight cut off of 6000 Daltons), that too with the help of cheap needle assembly. Needle assemblies, made of disposable syringes, thereby reduce the costs by at least 5 orders of magnitude. The process design is such that it requires no electricity for its production. The invention discusses the detailed composition and spinning of HE dialysis fibres, with comparable urea, creatinine clearance values, ultrafiltration coefficient (K) and Kt/V values as reported in the literatures for dialysis operation. 

We were told that the cartridge thus developed is ultra low cost, and the sum of parts do not even look like reaching Rs. 100 which is about 15-20 times lower than existing product in the market. The inventing team helped us explaining this with a summary of technology details. 

The basic technology behind extrusion in this article was the assembly based on disposable syringes. This is depicted Fig. 1(a). A syringe of 230 microns diameter was bent at angle of 120 degree and inserted into an outer needle of diameter 700 microns. Both the syringes were commercially available, each costing Rs. 10 (USD 0.15). This assembly was sealed with adhesive to make it leak proof and also to maintain the concentric arrangement of the needles. The extrusion mechanism was carried out as depicted in Fig. 1(b) and 1(c). The polymer flow was facilitated by the pressure applied (140-200 kPa) by the nitrogen cylinder and the water was flown from an overhead tank due to gravity. The minimum height maintained for the spinning of fibers was 160 cm from the ground. The water flowing through the syringe forms the hollow core of the fiber which, after extrusion, was put into the gelation bath containing normal tap water. The fibers were then wound on the spool. In this whole arrangement, there was no need of electricity anywhere, except in the final step where the spool was rotated by a variable voltage variable frequency drive. Cost of syringe assembly was $0.3 (Rs.20) and the rest of the paraphernalia too were non-expensive making this technology to be ultra-low cost.

The industrial partners of this project, M/s Forus Health Pvt. Ltd. And M/s Renalyx Health Systems are going ahead with the commercialization of the technology.

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