Fast nonlinear ion transport via field-induced hydrodynamic slip in sub-20-nm hydrophilic nanofluidic transistors

Electrolyte transport through an array of 20 nm wide, 20 μm long SiO_2 nanofluidic transistors is described. At sufficiently low ionic strength, the Debye screening length exceeds the channel width, and ion transport is limited by the negatively charged channel surfaces. At source−drain biases >5 V, the current exhibits a sharp, nonlinear increase, with a 20−50-fold conductance enhancement. This behavior is attributed to a breakdown of the zero-slip condition. Implications for energy conversion devices are discussed

Self-powered microfluidic chips for multiplexed protein assays from whole blood

We report herein on a self-powered, self-contained microfluidic-based chip designed to separate plasma from whole blood, and then execute an assay of a multiplexed panel of plasma biomarker proteins. The power source is based upon a chemical reaction that is catalytically triggered by the push of a button on the chip. We demonstrate assays of a dozen blood-based protein biomarkers using this automated, self-contained device. This platform can potentially permit high throughput, accurate, multiplexed blood diagnostic measurements in remote locations and by minimally trained individuals

High-Density, Multiplexed Patterning of Cells at Single-Cell Resolution for Tissue Engineering and Other Applications

Surface chemistry meets tissue engineering: A novel surface-patterning approach for creating arrays of DNA squares is combined with a unique method for DNA-encoding of cells to construct dense arrays of distinct single cells. The cell patterns can be transferred from the substrate surface into thin hydrogel films, and these layers can be stacked to form 3D tissue constructs

Integrated barcode chips for rapid, multiplexed analysis of proteins in microliter quantities of blood

As the tissue that contains the largest representation of the human proteome [1], blood is the most important fluid for clinical diagnostics [2, 3, 4]. However, although changes of plasma protein profiles reflect physiological or pathological conditions associated with many human diseases, only a handful of plasma proteins are routinely used in clinical tests. Reasons for this include the intrinsic complexity of the plasma proteome [1], the heterogeneity of human diseases and the rapid degradation of proteins in sampled blood [5]. We report an integrated microfluidic system, the integrated blood barcode chip that can sensitively sample a large panel of protein biomarkers over broad concentration ranges and within 10 min of sample collection. It enables on-chip blood separation and rapid measurement of a panel of plasma proteins from quantities of whole blood as small as those obtained by a finger prick. Our device holds potential for inexpensive, noninvasive and informative clinical diagnoses, particularly in point-of-care settings

A self-powered, one-step chip for rapid, quantitative and multiplexed detection of proteins from pinpricks of whole blood

We describe an automated, self-powered chip based on lateral flow immunoassay for rapid, quantitative, and multiplex protein detection from pinpricks of whole blood. The device incorporates on-chip purification of blood plasma by employing inertial forces to focus blood cells away from the assay surface, where plasma proteins are captured and detected on antibody “barcode” arrays. Power is supplied from the capillary action of a piece of adsorbent paper, and sequentially drives, over a 40 minute period, the four steps required to capture serum proteins and then develop a multiplex immunoassay. An 11 protein panel is assayed from whole blood, with high sensitivity and high reproducibility. This inexpensive, self-contained, and easy to operate chip provides a useful platform for point-of-care diagnoses, particularly in resource-limited settings

Targeted superparamagnetic iron oxide nanoparticles for early detection of cancer: Possibilities and challenges

Nanomedicine, the integration of nanotechnological tools in medicine demonstrated promising potential to revolutionize the diagnosis and treatment of various human health conditions. Nanoparticles (NPs) have shown much promise in diagnostics of cancer, especially since they can accommodate targeting molecules on their surface, which search for specific tumor cell receptors upon injection into the blood stream. This concentrates the NPs in the desired tumor location. Furthermore, such receptor-specific targeting may be exploited for detection of potential metastases in an early stage. Some NPs, such as superparamagnetic iron oxide NPs (SPIONs), are also compatible with magnetic resonance imaging (MRI), which makes their clinical translation and application rather easy and accessible for tumor imaging purposes. Furthermore, multifunctional and/or theranostic NPs can be used for simultaneous imaging of cancer and drug delivery. In this review article, we will specifically focus on the application of SPIONs in early detection and imaging of major cancer types. From the Clinical Editor: Super-paramagnetic iron oxide nanoparticles (SPIONs) have been reported by many to be useful as an MRI contrast agent in the detection of tumors. To further enhance the tumor imaging, SPIONs can be coupled with tumor targeting motifs. In this article, the authors performed a comprehensive review on the current status of using targeted SPIONS in tumor detection and also the potential hurdles to overcome. © 2015 Elsevier Inc. All rights reserved

Re-evaluation of the Indication and Limitation of Laparoscopic Salpingotomy for Tubal Pregnancy

Objective. We investigated the outcome of laparoscopic salpingotomy for tubal pregnancy by follow-up hysterosalpingography (HSG) or second look laparoscopy (SLL) and reexamined the indication and limitation of this conservative surgery.Study Design. From April 1991 to December 2003, we treated one hundred and eighty one cases of tubal pregnancy by laparoscopic salpingotomy. The tubal patency was assessed by either HSG or SLL performed at three months post-surgery. The successful patients at initial operation and the confirmed ipsilateral patent tubes at follow-up were classified as true successful cases (Group I). Even after successful operation, if the treated tubes were found occluded, they were considered as failure cases. Therefore, unsuccessful cases at initial surgery as well as at follow-up were categorized as Group II.Results. One hundred thirty four cases (74%) were successfully treated by salpingotomy at initial laparoscopy and also 85 of them (63.4%) were found truly successful at follow-up (Group I). The remaining 47 cases (26.0%) were unsuccessful at initial surgery and 18 (13.4%) cases at follow-up (Group II). Other patients who refused to accept a tubal patency test or not examined as a result of personal reason or lost follow-up comprised 31 cases. No difference in surgical outcome was observed with gestational age, intra-operative hemorrhage, size or anatomic location of pregnancy mass, and preoperative adhesions of the fallopian tube between these two groups of patients. However, pre-operative serum levels of hCG were significantly higher in Group II compared with Group I. In addition, the failure cases were more frequently associated with positive fetal heart beat (FHB), tubal rupture and a preoperative serum levels of hCG of more than 10,000 IU/L (p<0.05, χ2 test). The Log-rank test indicated a higher success in achieving pregnancy in Group I (p<0.05) than in Group II who desired for future pregnancy.Conclusion. Laparoscopic salpingotomy can be equally practiced as a conservative surgery for also proximal ectopic pregnancy and gestational mass size is not so much important and not a relative contraindication for conservative laparoscopic surgery as previously reported. Low preoperative hCG levels, absence of FHB, absence of tubal rupture initially or minimal rupture may be considered as suitable parameters for successful surgery and achieving future pregnancy.Without Figures and Table