Rheotaxis is one of the major migratory mechanisms used in autonomous swimmers such as sperms and bacteria. Here, we present a microfluidic chip using joint rheotaxis and boundary-following behavior that selects sperms based on the motility and persistence. The proposed device consists of a channel decorated with diamond-shaped pillars that create spots of increased velocity field and shear rate. These spots are supposed as hydrodynamic barriers that impede the passage of less motile sperms through the channels, while highly motile sperms were able to overcome the generated barrier and swim through the structures. The proposed device was able to populate the chamber with sorted sperms that were fully viable and motile. The experimental results validated the separation of highly motile sperms with enhanced motility parameters compared with the initial sample. Our device was able to improve linear straight velocity, curvilinear velocity, and average path velocity of the sorted population surpassing 35%, compared with the raw semen. The processing time was also reduced to 20 min.

1.
B. R.
Winters
and
T. J.
Walsh
, “
The epidemiology of male infertility
,”
Urol. Clin. North Am.
41
(
1
),
195
204
(
2014
).
2.
G.
Cavallini
and
G.
Beretta
,
Clinical Management of Male Infertility
(
Springer International Publishing
,
New York
,
2015
).
3.
W.
Ombelet
,
I.
Cooke
,
S.
Dyer
,
G.
Serour
, and
P.
Devroey
, “
Infertility and the provision of infertility medical services in developing countries
,”
Hum. Reprod. Update
14
(
6
),
605
621
(
2008
).
4.
A.
Khatun
,
M. S.
Rahman
, and
M.-G.
Pang
, “
Clinical assessment of the male fertility
,”
Obstet. Gynecol. Sci.
61
(
2
),
179
(
2018
).
5.
J. G.
Alvarez
,
J. L.
Lasso
,
L.
Blasco
,
R. C.
Nuñez
,
S.
Heyner
,
P. P.
Caballero
, and
B. T.
Storey
, “
Centrifugation of human spermatozoa induces sublethal damage; separation of human spermatozoa from seminal plasma by a dextran swim-up procedure without centrifugation extends their motile lifetime
,”
Hum. Reprod.
8
(
7
),
1087
1092
(
1993
).
6.
R. M.
Schultz
and
C. J.
Williams
, “
The science of ART
,”
Science
296
(
5576
),
2188
2190
(
2002
).
7.
J. C. M.
Dumoulin
, “
Embryo development and chromosomal anomalies after ICSI: Effect of the injection procedure
,”
Hum. Reprod.
16
(
2
),
306
312
(
2001
).
8.
P.
Rubino
,
P.
Viganò
,
A.
Luddi
, and
P.
Piomboni
, “
The ICSI procedure from past to future: A systematic review of the more controversial aspects
,”
Hum. Reprod. Update
22
(
2
),
194
227
(
2016
).
9.
C.
Celik-Ozenci
, “
Sperm selection for ICSI: Shape properties do not predict the absence or presence of numerical chromosomal aberrations
,”
Hum. Reprod.
19
(
9
),
2052
2059
(
2004
).
10.
Y.
Yang
,
Y.
Chen
,
H.
Tang
,
N.
Zong
, and
X.
Jiang
, “
Microfluidics for biomedical analysis
,”
Small Methods
4
(
4
),
1900451
(
2020
).
11.
N.
Convery
and
N.
Gadegaard
, “
30 years of microfluidics
,”
Micro Nano Eng.
2
,
76
91
(
2019
).
12.
A. A. S.
Bhagat
,
H.
Bow
,
H. W.
Hou
,
S. J.
Tan
,
J.
Han
, and
C. T.
Lim
, “
Microfluidics for cell separation
,”
Med. Biol. Eng. Comput.
48
(
10
),
999
1014
(
2010
).
13.
J.-K.
Wu
,
P.-C.
Chen
,
Y.-N.
Lin
,
C.-W.
Wang
,
L.-C.
Pan
, and
F.-G.
Tseng
, “
High-throughput flowing upstream sperm sorting in a retarding flow field for human semen analysis
,”
Analyst
142
(
6
),
938
944
(
2017
).
14.
S. A.
Vasilescu
,
L.
Ding
,
F. Y.
Parast
,
R.
Nosrati
, and
M. E.
Warkiani
, “
Sperm quality metrics were improved by a biomimetic microfluidic selection platform compared to swim-up methods
,”
Microsyst. Nanoeng.
9
(
1
),
37
(
2023
).
15.
A. B.
Alias
,
H.-Y.
Huang
, and
D.-J.
Yao
, “
A review on microfluidics: An aid to assisted reproductive technology
,”
Molecules
26
(
14
),
4354
(
2021
).
16.
S. M.
Knowlton
,
M.
Sadasivam
, and
S.
Tasoglu
, “
Microfluidics for sperm research
,”
Trends Biotechnol.
33
(
4
),
221
229
(
2015
).
17.
R.
Nosrati
,
M.
Vollmer
,
L.
Eamer
,
M. C.
San Gabriel
,
K.
Zeidan
,
A.
Zini
, and
D.
Sinton
, “
Rapid selection of sperm with high DNA integrity
,”
Lab Chip
14
(
6
),
1142
(
2014
).
18.
S.
Xiao
,
J.
Riordon
,
M.
Simchi
,
A.
Lagunov
,
T.
Hannam
,
K.
Jarvi
,
R.
Nosrati
, and
D.
Sinton
, “
Fertdish: Microfluidic sperm selection-in-a-dish for intracytoplasmic sperm injection
,”
Lab Chip
21
(
4
),
775
783
(
2021
).
19.
M.
Bouloorchi Tabalvandani
,
Z.
Saeidpour
,
Z.
Habibi
,
S.
Javadizadeh
,
S. A.
Firoozabadi
, and
M.
Badieirostami
, “
Microfluidics as an emerging paradigm for assisted reproductive technology: A sperm separation perspective
,”
Biomed. Microdevices
26
(
2
),
23
(
2024
).
20.
E. T. Y.
Leung
,
C.-L.
Lee
,
X.
Tian
,
K. K. W.
Lam
,
R. H. W.
Li
,
E. H. Y.
Ng
,
W. S. B.
Yeung
, and
P. C. N.
Chiu
, “
Simulating nature in sperm selection for assisted reproduction
,”
Nat. Rev. Urol.
19
(
1
),
16
36
(
2022
).
21.
C. H.
Huang
,
C. H.
Chen
,
T. K.
Huang
,
F.
Lu
,
J. Y.
Jen Huang
, and
B. R.
Li
, “
Design of a gradient-rheotaxis microfluidic chip for sorting of high-quality sperm with progressive motility
,”
IScience
26
(
8
),
107356
(
2023
).
22.
K.
Miki
and
D. E.
Clapham
, “
Rheotaxis guides mammalian sperm
,”
Curr. Biol.
23
(
6
),
443
452
(
2013
).
23.
Y.
Yan
,
B.
Zhang
,
Q.
Fu
,
J.
Wu
, and
R.
Liu
, “
A fully integrated biomimetic microfluidic device for evaluation of sperm response to thermotaxis and chemotaxis
,”
Lab Chip
21
(
2
),
310
318
(
2021
).
24.
L.
Xie
,
R.
Ma
,
C.
Han
,
K.
Su
,
Q.
Zhang
,
T.
Qiu
,
L.
Wang
,
G.
Huang
,
J.
Qiao
,
J.
Wang
, and
J.
Cheng
, “
Integration of sperm motility and chemotaxis screening with a microchannel-based device
,”
Clin. Chem.
56
(
8
),
1270
1278
(
2010
).
25.
J. T. W.
Berendsen
,
S. A.
Kruit
,
N.
Atak
,
E.
Willink
, and
L. I.
Segerink
, “
Flow-free microfluidic device for quantifying chemotaxis in spermatozoa
,”
Anal. Chem.
92
(
4
),
3302
3306
(
2020
).
26.
V.
Kantsler
,
J.
Dunkel
,
M.
Blayney
, and
R. E.
Goldstein
, “
Rheotaxis facilitates upstream navigation of mammalian sperm cells
,”
eLife
3
,
e02403
(
2014
).
27.
S.
Pérez-Cerezales
,
S.
Boryshpolets
, and
M.
Eisenbach
, “
Behavioral mechanisms of mammalian sperm guidance
,”
Asian J. Androl.
17
(
4
),
628
–632 (
2015
).
28.
Z.
Zhang
,
J.
Liu
,
J.
Meriano
,
C.
Ru
,
S.
Xie
,
J.
Luo
, and
Y.
Sun
, “
Human sperm rheotaxis: A passive physical process
,”
Sci. Rep.
6
,
23553
(
2016
).
29.
M.
Yaghoobi
,
M.
Azizi
,
A.
Mokhtare
,
F.
Javi
, and
A.
Abbaspourrad
, “
Rheotaxis quality index: A new parameter that reveals male mammalian in vivo fertility and low sperm DNA fragmentation
,”
Lab Chip
22
(
8
),
1486
1497
(
2022
).
30.
J.
Romero-Aguirregomezcorta
,
R.
Laguna-Barraza
,
R.
Fernández-González
,
M.
Štiavnická
,
F.
Ward
,
J.
Cloherty
,
D.
McAuliffe
,
P. B.
Larsen
,
A. M.
Grabrucker
,
A.
Gutiérrez-Adán
,
D.
Newport
, and
S.
Fair
, “
Sperm selection by rheotaxis improves sperm quality and early embryo development
,”
Reproduction
161
(
3
),
343
352
(
2021
).
31.
S.
Zeaei
,
M.
Zabetian Targhi
,
I.
Halvaei
, and
R.
Nosrati
, “
High-DNA integrity sperm selection using rheotaxis and boundary following behavior in a microfluidic chip
,”
Lab Chip
23
(
9
),
2241
2248
(
2023
).
32.
A.
Heydari
,
M.
Zabetian Targhi
,
I.
Halvaei
, and
R.
Nosrati
, “
A novel microfluidic device with parallel channels for sperm separation using spermatozoa intrinsic behaviors
,”
Sci. Rep.
13
(
1
),
1185
(
2023
).
33.
M.
Zaferani
,
G. D.
Palermo
, and
A.
Abbaspourrad
, “
Strictures of a microchannel impose fierce competition to select for highly motile sperm
,”
Sci. Adv.
5
(
2
),
eaav2111
(
2019
).
34.
M.
Yaghoobi
,
A.
Abdelhady
,
A.
Favakeh
,
P.
Xie
,
S.
Cheung
,
A.
Mokhtare
,
Y. L.
Lee
,
A. V.
Nguyen
,
G.
Palermo
,
Z.
Rosenwaks
,
S. H.
Cheong
, and
A.
Abbaspourrad
, “
Faster sperm selected by rheotaxis leads to superior early embryonic development in vitro
,”
Lab Chip
24
(
2
),
210
223
(
2024
).
35.
M.
Bouloorchi Tabalvandani
,
S.
Javadizadeh
, and
M.
Badieirostami
, “
Bio-inspired progressive motile sperm separation using joint rheotaxis and boundary-following behavior
,”
Lab Chip
24
(
6
),
1636
1647
(
2024
).
36.
C.
Alquézar-Baeta
,
S.
Gimeno-Martos
,
S.
Miguel-Jiménez
,
P.
Santolaria
,
J.
Yániz
,
I.
Palacín
,
A.
Casao
,
J. Á.
Cebrián-Pérez
,
T.
Muiño-Blanco
, and
R.
Pérez-Pé
, “
OpenCASA: A new open-source and scalable tool for sperm quality analysis
,”
PLoS Comput. Biol.
15
(
1
),
e1006691
(
2019
).
37.
C. k.
Tung
,
F.
Ardon
,
A.
Roy
,
D. L.
Koch
,
S. S.
Suarez
, and
M.
Wu
, “
Emergence of upstream swimming via a hydrodynamic transition
,”
Phys. Rev. Lett.
114
(
10
),
108102
(
2015
).
38.
E.
Dadkhah
,
M. A.
Hajari
,
S.
Abdorahimzadeh
,
A.
Shahverdi
,
F.
Esfandiari
,
N.
Ziarati
,
M.
Taghipoor
, and
L.
Montazeri
, “
Development of a novel cervix-inspired tortuous microfluidic system for efficient, high-quality sperm selection
,”
Lab Chip
23
(
13
),
3080
3091
(
2023
).
39.
M.
Zaferani
,
S. H.
Cheong
, and
A.
Abbaspourrad
, “
Rheotaxis-based separation of sperm with progressive motility using a microfluidic corral system
,”
Proc. Natl. Acad. Sci. U.S.A.
115
(
33
),
8272
8277
(
2018
).
You do not currently have access to this content.