A Microfluidic Device for Simultaneous Extraction of Plasma, Red Blood Cells, and On-Chip White Blood Cell Trapping

Song

Journal of Nanomaterials

et al. 2021

Massive bleeding is a serious medical complication arising from trauma, surgery, and invasive procedures. In this case, timely and effective hemostasis must be applied to patients. The aim of this study is to compare transfusion therapies guided by thromboelastogram (TEG) and conventional coagulation tests (CCTs) during orthopedic surgery, focusing on blood-component transfusion and coagulation function of patients. The patients who underwent orthopedic surgery in our hospital from May 2019 to November 2020 were retrospectively analyzed. According to different transfusion-guiding strategies, the patients were assigned into the CCT group containing 214 patients and the TEG group containing 266 patients. The TEG group used fewer volumes of blood products including red blood cell (RBC) suspension, fresh-frozen plasma, cryoprecipitate, and apheresis platelets than the CCT group ( P < 0.05 ). After orthopedic surgery, the hemoglobin (Hb) and RBC counts were decreased, but the white blood cell (WBC) counts were increased in all patients receiving whether transfusion therapy guided by TEG or CCTs. Importantly, the TEG group exhibited fewer WBC counts concomitant with higher Hb and more RBC counts than the CCT group ( P < 0.05 ). There was no significant difference on the platelet (PLT) counts between the two groups before and after orthopedic surgery ( P > 0.05 ). Significant declines on thrombin time (TT), partial activated thromboplastin time (PATT), prothrombin time (PT), and d-dimer (D-D), along with an increase on fibrinogen (FIB) were observed in two groups after surgery. The TEG group showed reduced TT, PATT, PT, D-D, and elevated FIB compared to the CCT group ( P < 0.05 ). Posttransfusion, the K value (time to reach a certain clot strength) and R value (coagulation reaction time) were decreased, the angle (α) value (clot formation rate), MA value (maximum amplitude), and CI (coagulation index) were increased in the TEG group ( P < 0.05 ). When the liver function was assessed, it was found that the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total serum bilirubin (TBIL) were increased significantly, and albumin (ALB) was decreased between the two groups after surgery, but the TEG group with lower levels of ALT, AST, and TBIL and a higher level of ALB than the CCT group ( P < 0.05 ). With regard to the renal function, two groups had increased levels of serum creatinine (Scr) and blood urea nitrogen (BUN) with a declined uric acid (UA) level after surgery; however, the patients in the TEG group had lower levels of Scr and BUN and a higher level of UA compared to the CCT group ( P < 0.05 ). In view of above data, TEG-guided transfusion therapy could reduce use of blood products, optimize blood components, and improve coagulation function for patients undergoing orthopedic surgery. TEG-guided transfusion therapy may prevent liver and renal dysfunction after orthopedic surgery.

Section: Discussionmentioning

confidence: 99%

Thromboelastogram-Guided Transfusion Therapy Reduces Blood-Component Transfusion and Improves Coagulation Function during Orthopedic Surgery

Song

Journal of Nanomaterials

et al. 2021

“…Furthermore, unlike other microfluidic-based approaches that require complicated instruments and operation, 22,[24][25][26][27][44][45][46] our approach only requires a small syringe pump and the miniaturized nanosieve device, thus it could be used for both lab-based or POC diagnosis.…”

Section: Discussionmentioning

confidence: 99%

“…18,19 Cell leakage is another challenge as the bacteria can deform to pass through the pores. In recent years, microfluidics-based approaches, such as inertial force separation, 20,21 hydrodynamic separation, 22,23 electrophoresis, 24,25 and acoustics separation, 26,27 have been developed to efficiently separate and detect pathogens; however, all of these methods have limitations, either require sophisticated microfluidic designs or complicated instruments. Therefore, physical barriers such as "T-junction" 28,29 and micro-obstacle arrays 30,31 were introduced to capture the cells from bodily fluids; yet, most of the bacteria sizes range between 0.5 to 5 µm, making the fabrication process challenging.…”

mentioning

confidence: 99%

Efficient Escherichia coli (E. coli) Trapping and Retrieval from Bodily Fluids via a Three-Dimensional (3D) Microbeads Stacked Nano-Device

Chen¹,

Miller²,

Cao³

et al. 2019

Preprint

<div>A micro- and nano-fluidic device stacked with magnetic beads is developed to efficiently trap, concentrate, and retrieve Escherichia coli (E. coli) from bacteria suspension</div><div>and pig plasma. The small voids between the magnetic beads are used to physically isolate the bacteria in the device. We use computational fluid dynamics (CFD), 3D</div><div>tomography technology, and machine learning to probe and explain the bead stacking in a small 3D space with various flow rates. A combination of beads with different sizes is utilized to achieve a high capture efficiency of ~86% with a flow rate of 50 μL/min. Leveraging the high deformability of this device, the E. coli sample is retrieved from the designated bacteria suspension by applying a higher flow rate, followed by rapid magnetic separation. This unique function is also utilized to concentrate E. coli from the original bacteria suspension. An on-chip concentration</div><div>factor of ~11× is achieved by inputting 1,300 μL of the E. coli sample and then concentrating it in 100 μL buffer.</div><div>Importantly, this multiplexed, miniaturized, inexpensive, and transparent device is easy to fabricate and operate, making it ideal for pathogen separation in both laboratory and pointof- care (POC) settings.</div>

“…This corresponds to a ~15X reduction in sample volume compared with a typical ELISA in DMF. With the development of microfluidic methods for extracting plasma from whole blood [ 28 , 29 ], it may be possible to perform a panel of DMF-based ELISA using only a fraction of the volume from a single blood draw. Others have found that under the same experimental conditions, chemiluminescent detection can quantify lower concentrations of targets [ 30 ].…”

Section: Introductionmentioning

confidence: 99%

Heterogeneous Immunoassay Using Channels and Droplets in a Digital Microfluidic Platform

Liu

Papautsky

2019

Micromachines

This work presents a heterogeneous immunoassay using the integrated functionalities of a channel and droplets in a digital microfluidic (DMF) platform. Droplet functionality in DMF allows for the programmable manipulation of discrete sample and reagent droplets in the range of nanoliters. Pressure-driven channels become advantageous over droplets when sample must be washed, as the supernatant can be thoroughly removed in a convenient and rapid manner while the sample is immobilized. Herein, we demonstrate a magnetic bead-based, enzyme-linked immunosorbent assay (ELISA) using ~60 nL of human interleukin-6 (IL-6) sample. The wash buffer was introduced in the form of a wall-less virtual electrowetting channel by a syringe pump at the flow rate of 10 μL/min with ~100% bead retention rate. Critical parameters such as sample wash flow rate and bead retention rate were optimized for reliable assay results. A colorimetric readout was analyzed in the International Commission on Illumination (CIE) color space without the need for costly equipment. The concepts presented in this work are potentially applicable in rapid neonatal disease screening using a finger prick blood sample in a DMF platform.