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FX high-flux and FX low-flux dialyzers

Innovation at all levels

  • State-of-the art FX-class design
  • Efficient removal of uraemic toxins with the Helixone® membrane
  • INLINE steam sterilized
  • Available in both low-flux and high-flux ranges

Key features

FX dialyzers

Several state-of-the-art technologies have been combined to create the distinctive functional features of the FX dialyzers. The fibre bundle geometry, the membrane nanostructure, the flow port and the housing design all provide advantages in terms of performance, hemodynamics, dialyzate flow, as well as safety and handling.

Lateral blood-inlet ports provide a homogenous blood-flow path

Improved design and refined hemodynamics

  • The lateral blood-inlet port provides a homogenous blood-flow path, avoiding low velocity stagnation zones in the header region
  • The risk of accidental kinking of bloodlines is very low

Radial dialyzate flow

  • The pinnacle structure of the polypropylene housing ensures a uniform dialyzate flow around the entire fiber bundle
  • A high packing density of the fiber bundle and a special wavy fiber structure to avoid dialyzate channeling
  • Combined these features enable the constant performance of all FX dialyzers

Optimum fiber dimensions

  • The reduced inner diameter and wall thickness of the fiber increase the internal filtration and minimize diffusive resistance
  • A significant increase of both the diffusive and convective clearances is therefore achieved, allowing the efficient removal of a broad spectrum of uraemic toxins 

Dialyzer weight

  • Dialyzer weight is a crucial factor not only in logistics but also in waste management
  • The housing of FX dialyzers is made of polypropylene. In comparison to the widely used polycarbonate it is much lighter
  • The result: FX dialyzers weigh around half as much as most dialyzers.
  • FX60 = 105g

Technology

Helixone® — the advanced polysulfone membrane

  • Nanotechnology membrane fabrication procedures (Nano Controlled Spinning Technology, NCS™) provide Helixone® with a highly-defined pore structure and distribution at the innermost, separating region of the membrane1,2
  • Unlike conventional pores which were rugged and uneven in shape, the pores at the inner layer of the Helixone® membrane are smooth and cylindrical
  • This reduces the resistance of the molecules when travelling through the pores and allows for enhanced removal

Conventional pores

Helixone® pores

Helixone® has been specially designed to meet the demands of both low-flux and high-flux therapies:

  • More even distribution of pores
  • Estimated increased average pore size of 1.8 nm (low-flux) and 3.3 nm (high-flux)
  • Increased performance per unit of surface area

NCSTM results in optimized pore size distribution and larger average pore size

Performance (K0) per m² surface area

INLINE steam sterilization – purity ensured

No chemical residuals. Low rinsing volumes. Lower costs.

INLINE steam sterilisation process

INLINE steam sterilization – how it works

  1. Both the blood and the dialysate compartment of the dialyzers are rinsed continuously with steam at a temperature of 121°C for a minimum of 15 minutes, or a higher temperature for a shorter time, to ensure sterility. 
  2. The dialyzer is rinsed with sterile water
  3. Every dialyzer is tested for fiber integrity using a bubble-point test
  4. The dialyzers are dried with warm, sterile air
  5. Finally, after drying the blood inlet and outlet ports are closed

INLINE steam sterilization – the benefits

  • Highly pure, sterile and pyrogen-free dialyzers without any potentially harmful residuals from sterilization
  • Biocompatibility of membranes remains unaffected from sterilization
  • Optimized use of resources due to low rinsing volumes: only 500 mL is required
  • Dry dialyzers with minimized risk of contamination due to microbial growth

Fibre integrity testing

  • All dialyzers have to pass the bubble point test as part of the INLINE steam sterilization process
  • Sterile air is pressed into the dialyzate compartment while the blood compartment contains sterile water
  • If any leakages were present in the membrane, air would pass through the membrane and create bubbles
  • Dialyzers failing the integrity test are discarded
  • This integrity test minimizes the risk of fibre ruptures and the risk of blood leakages

Performance data

FX low-flux dialyzers

FX low-flux dialyzers FX 5 FX 8 FX 10
Ultrafiltration coefficient (ml/h x mmHg) 8 12 14
Clearance: QB: (200ml/min)      
Urea 180 191 193
Creatinine 165 178 181
Phosphate 141 160 170
Vitamin B12 88 107 121
Clearance: QB: (300ml/min)       
Urea 228 254 261
Creatinine 200 225 231
Phosphate 164 194 210
Vitamin B12 94 120 138
Clearance: QB: (400ml/min)       
Urea   293 303
Creatinine   252 260
Phosphate   213 233
Vitamin B12   126 146
The in vitro performance data were obtained with QD = 500ml/min:
QF = 0ml/min; T=37°C (ISO8637)
The ultrafiltration coefficients were maintained using human blood,
Hct = 32%, protein content 6%
Effective surface area (m²) 1.0 1.4 1.8
Blood filling volume (ml) 54 74 95
Membrane material Helixone®
Housing material Polypropylene
Potting compound Polyurethane
Sterilization method INLINE steam
Application HD

FX high-flux dialyzers

FX high-flux dialyzers FX 40 FX 50 FX 60 FX 80 FX 100
Ultrafiltration coefficient (ml/h x mmHg) 20 33 46 59 73
Clearance: QB: (200ml/min)          
Urea 170 189 193 197  
Creatinine 144 170 182 189  
Phosphate 138 165 177 185  
Vitamin B12 84 115 135 148  
Inulin 54 76 95 112  
Clearance: QB: (300ml/min)           
Urea   250 261 276 278
Creatinine   210 230 250 261
Phosphate   201 220 239 248
Vitamin B12   130 155 175 192
Inulin   81 104 125 142
Clearance: QB: (400ml/min)           
Urea     303 362 331
Creatinine     262 287 304
Phosphate     248 272 284
Vitamin B12     167 190 213
Inulin     109 133 152
The in vitro performance data were obtained with QD = 500ml/min:
QF = 0ml/min; T=37°C (ISO8637)
The ultrafiltration coefficients were maintained using human blood,
Hct = 32%, protein content 6%
Effective surface area (m²) 0.6 1.0 1.4 1.8 2.2
Blood filling volume (ml) 32 53 74 95 116
Membrane material Helixone®
Housing material Polypropylene
Potting compound Polyurethane
Sterilization method INLINE steam
Application HD/HDF/HF

FX hemodiafilters

FX hemodiafilters FX 600 FX 800 FX 1000
Ultrafiltration coefficient (ml/h x mmHg) 52 63 75
Clearance: QB: (200ml/min)QF: (0ml/min)      
Urea 196 198  
Creatinine 184 190  
Phosphate 180 184  
Vitamin B12 141 149  
Inulin 101 110  
Clearance: QB: (300ml/min) QF: (75ml/min)        
Urea 284 289 290
Creatinine 262 271 280
Phosphate 254 262 269
Vitamin B12 199 209 211
Inulin 150 161 164
Clearance: QB: (400ml/min) QF: (100ml/min)      
Urea 351 361 364
Creatinine 313 328 343
Phosphate 301 313 325
Vitamin B12 229 241 244
Inulin 172 185 188
The in vitro performance data were obtained with QD = 500ml/min:
T=37°C (ISO8637)
The ultrafiltration coefficients were maintained using human blood,
Hct = 32%, protein content 6%
Effective surface area (m²) 1.5 1.8 2.2
Wall thickness / inner diameter (µm) 35/210    
Blood filling volume (ml) 97 118 138
Membrane material Helixone®
Housing material Polypropylene
Potting compound Polyurethane
Sterilization method INLINE steam
Application HD/HDF
Related content

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1 Bowry, S.K.: Nano-controlled membrane spinning technology: Regulation of pore size, distribution and morphology of a new polysulfone dialysis membrane. In Hemodialysis Technology (eds: Ronco, C., La Greca, G.) Contributions to Nephrology, Vol. 137: 85-94 (2002)

2 Ronco, C., Nissenson, A.R.: Does nanotechnology apply to dialysis? Blood Purification 19: 347-352 (2001)