Programmable bio-nanochip technology for the diagnosis of cardiovascular disease at the point-of-care.

Cardiovascular disease remains the leading cause of death in the world and continues to serve as the major contributor to healthcare costs. Likewise, there is an ever-increasing need and demand for novel and more efficient diagnostic tools for the early detection of cardiovascular disease, especially at the point-of-care (POC). This article reviews the programmable bio-nanochip (P-BNC) system, a new medical microdevice approach with the capacity to deliver both high performance and reduced cost. This fully integrated, total analysis system leverages microelectronic components, microfabrication techniques, and nanotechnology to noninvasively measure multiple cardiac biomarkers in complex fluids, such as saliva, while offering diagnostic accuracy equal to laboratory-confined reference methods. This article profiles the P-BNC approach, describes its performance in real-world testing of clinical samples, and summarizes new opportunities for medical microdevices in the field of cardiac diagnostics.

Programmable bio-nano-chip systems for serum CA125 quantification: toward ovarian cancer diagnostics at the point-of-care.

Point-of-care (POC) implementation of early detection and screening methodologies for ovarian cancer may enable improved survival rates through early intervention. Current laboratory-confined immunoanalyzers have long turnaround times and are often incompatible with multiplexing and POC implementation. Rapid, sensitive, and multiplexable POC diagnostic platforms compatible with promising early detection approaches for ovarian cancer are needed. To this end, we report the adaptation of the programmable bio-nano-chip (p-BNC), an integrated, microfluidic, and modular (programmable) platform for CA125 serum quantitation, a biomarker prominently implicated in multimodal and multimarker screening approaches. In the p-BNCs, CA125 from diseased sera (Bio) is sequestered and assessed with a fluorescence-based sandwich immunoassay, completed in the nano-nets (Nano) of sensitized agarose microbeads localized in individually addressable wells (Chip), housed in a microfluidic module, capable of integrating multiple sample, reagent and biowaste processing, and handling steps. Antibody pairs that bind to distinct epitopes on CA125 were screened. To permit efficient biomarker sequestration in a three-dimensional microfluidic environment, the p-BNC operating variables (incubation times, flow rates, and reagent concentrations) were tuned to deliver optimal analytical performance under 45 minutes. With short analysis times, competitive analytical performance (inter- and intra-assay precision of 1.2% and 1.9% and limit of detection of 1.0 U/mL) was achieved on this minisensor ensemble. Furthermore, validation with sera of patients with ovarian cancer (n = 20) showed excellent correlation (R(2) = 0.97) with gold-standard ELISA. Building on the integration capabilities of novel microfluidic systems programmed for ovarian cancer, the rapid, precise, and sensitive miniaturized p-BNC system shows strong promise for ovarian cancer diagnostics.

Nano-bio-chips for high performance multiplexed protein detection: determinations of cancer biomarkers in serum and saliva using quantum dot bioconjugate labels.

The integration of semiconductor nanoparticle quantum dots (QDs) into a modular, microfluidic biosensor for the multiplexed quantitation of three important cancer markers, carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), and Her-2/Neu (C-erbB-2) was achieved. The functionality of the integrated sample processing, analyte capture and detection modalities was demonstrated using both serum and whole saliva specimens. Here, nano-bio-chips that employed a fluorescence transduction signal with QD-labeled detecting antibody were used in combination with antigen capture by a microporous agarose bead array supported within a microfluidics ensemble so as to complete the sandwich-type immunoassay. The utilization of QD probes in this miniaturized biosensor format resulted in signal amplification 30 times relative to that of standard molecular fluorophores as well as affording a reduction in observed limits of detection by nearly 2 orders of magnitude (0.02 ng/mL CEA; 0.11 pM CEA) relative to enzyme-linked immunosorbent assay (ELISA). Assay validation studies indicate that measurements by the nano-bio-chip system correlate to standard methods at R(2)=0.94 and R(2)=0.95 for saliva and serum, respectively. This integrated nano-bio-chip assay system, in tandem with next-generation fluorophores, promises to be a sensitive, multiplexed tool for important diagnostic and prognostic applications.

Alu profiling of primary and metastatic nonsmall cell lung cancer.

The metastatic potential of nonsmall cell carcinoma of lung (NSCLC), is currently recognized post factum, when lymph nodes or distant organs are already involved. Our ability to determine which tumors have acquired metastatic potential could help direct therapy to be more aggressive or less aggressive based upon this information. Evaluation of microsatellite instability via detection of LOH at specific loci may be useful in identifying specific markers and/or genes associated with this process. We examined Alu insertional elements as a potential marker of genetic changes associated with the metastatic potential of NSCLC. We analyzed archived, paraffin embedded tissue from 20 proven cases of NSCLC. DNA was extracted from 10 micron paraffin sections and amplified using an Alu PCR protocol. This technique does not examine specific loci but rather results in a banding profile of cellular genomic DNA. Informative allelic banding patterns, noted as differences between primary and metastatic lesions from the same patient, were observed in five of six cases (83%) with intrapulmonary metastases and in only nine of 14 (64%) cases with extrapulmonary metastases. Multiple genomic changes were detected in metastatic tumor cells as compared to normal lung tissue or primary lung tumor tissue. It appears that Alu profiling may be useful in the detection of metastatic vs primary lesions, and this technique may offer a method for identifying novel genes responsible for tumor progression and metastases.