Standard DVD Research Articles

Do I Need to Ask Permission? Applying Fair Use to Educational Activities.

Do I Need to Ask Permission? Applying Fair Use to Educational Activities.

Interferometric multilayered nanomaterials for imaging unlabeled biorecognition events

Abstract There is an intense scientific activity on nanomaterials for biosensing, supported by their great potential to conceive powerful applications in chemistry, biology, and medicine. In addition to meet the required analytical parameters, the social impact of these advances is also highly influenced by cost, simplicity, and portability aspects, which are critical in label-free systems. This paper addresses the design, development, and experimental assessment of multilayered nanomaterials to transduce unlabeled biorecognition assays as both constructive and destructive interferences, by means of simple and effective imaging setups. The materials rely on superposed nanometric films of metals (gold and Ag-In-Sb-Te alloy) and a dielectric (zinc sulphide) deposited on a polymeric substrate. They are tailored to display maximal (constructive and destructive) interferences for immunoassays performed on their surface, and then fabricated by sputtering and characterized by focused ion beam scanning electron microscopy. Herein we also address the development of a simple optical setup that exploits standard DVD laser units to scan by imaging the reflected interferometric response of microarrayed immunoassays. The bioanalytical performance of the approach is experimentally assessed using a representative model immunoassay (BSA/anti-BSA) and a competitive immunoassay to quantify a low molecular weight drug (sulfasalazine), reaching detection limits of 460 and 11 ng mL−1 of unlabeled targets, respectively. This study also explores two alternative one-shot interferometric imaging approaches that provide insights into simpler and faster strategies for label-free biosensing.

Treatment with Daratumumab in Patients with Multiple Myeloma Associated AL Amyloidosis

Treatment with Daratumumab in Patients with Multiple Myeloma Associated AL Amyloidosis

Lab-on-DVD: standard DVD drives as a novel laser scanning microscope for image based point of care diagnostics

We present a novel "Lab-on-DVD" system and demonstrate its capability for rapid and low-cost HIV diagnostics by counting CD4+ cells isolated from whole blood. We show that a commercial DVD drive can, with certain modifications, be turned into an improved DVD-based laser scanning microscope (DVD-LSM). The system consists of a multi-layered disposable polymer disc and a modified commercial DVD reader with rotational control for sample handling, temperature control for optimized bioassay, a photodiode array for detection, and software for signal processing and user interface - all the necessary components required for a truly integrated lab-on-a-chip system, with the capability to deliver high-resolution images down to 1 μm in size. Using discs modified with antibodies, we specifically captured CD4+ cells from whole blood, demonstrating single cell resolution imaging. The novel integrated DVD platform with sub-micron image resolution brings, for the first time, affordable cellular diagnostic testing to the point-of-care and should be readily applicable at resource-limited settings.

News

News

Influenza A virus infection diagnosis based on DVD reader technology

Diagnosis tests for Influenza A require rapidity and cost-effectiveness for on-site analysis. The optical Compact Disk technology is a potential candidate to provide such requirements. In this paper, a simple, competitive assay for Influenza diagnosis is set up that demonstrates the great potential of the developed methodology in problems such as the massive analyses for mass populations. The polycarbonate surface chemical modification of commercial DVDs to covalently attach Influenza-capture antibodies is reported, along with the full characterization of each modification step and the development of the detection sandwich immunoassay employing a standard DVD reader for quantification. The method includes positive and negative controls for each sample, as well as internal standards, if necessary, to normalize the signal. The assay is seen to be very sensitive with a detection limit of 29 ng mL−1. Furthermore, real spiked saliva samples were analyzed with quantitative recoveries in all cases.

Oxygen Plasma Treated Interactive Polycarbonate DNA Microarraying Platform

A novel DNA microarrying platform based on oxygen plasma activation of polycarbonate surface of compact disks (DVD) is presented. Carboxylic acid groups are generated in few seconds on polycarbonate in an efficient, fast, and clean way. Following this surface activation strategy, amino-modified oligonucleotide probes were covalently attached, reaching an immobilization density of 2 pmol cm(-2). Atomic force microscopy imaging revealed the nondestructive character of this treatment when applied for short times, allowing for disk scanning in standard DVD drives. DNA assays performed on oxygen plasma treated disks resulted very efficient with maximum hybridization yield of 93% and reaching a low limit of detection (200 pM) for perfect match synthetic oligonucleotide targets when reading the disk with a standard drive as detector. The approach was also evaluated by scoring single nucleotide polymorphisms with a discrimination ratio of 12.8. As proof of concept, the oxygen plasma treated interactive polycarbonate DNA microarraying platform was applied to the detection of PCR products of Salmonella spp., reaching a detection limit of 2 nM that corresponds to a DNA concentration of only 1 c.f.u./mL. The results confirm the suitability of the microarray platform for analysis of biological samples with high sensitivity.

Procedures Consult

Procedures Consult

DVD information – Volume 13 (Issue 13/3)

This DVD contains both audio and video files. The DVD will play audio and audiovisual tracks either on a standard DVD player or on your computer. Full information related to this DVD can be found in the relevant articles.

Cell analysis in a microfluidic cytometer applying a DVD pickup head

In this paper we present an optical detection system for single biological cells that utilizes a standard DVD pickup head. In a feasibility study we have shown the detection for different particles and cells (yeast) suspended on a platinum mirror. For those experiments the integrated magnetic actuator of the pickup was used to simulate the particle movement and we found a remarkable sensitivity. Then a microfluidic flow cell with an integrated mirror was designed to be able to measure particles in a cytometric setup. The mirror at the bottom of the flow channel reflects the focused laser beam back to the integrated photodiodes. The advantage of using a DVD pickup head is not only in the low cost but also in the ability to use the integrated magnetic actuators to adjust for alignment errors between flow channel and pickup. Measurement results are given that show the high sensitivity and good repeatability for polystyrene beads and erythrocytes from cattle. In a two-parameter plot the cytometric separation of a mixture of counting beads and erythrocytes into two sub-populations is demonstrated.

Duel of the Discs

Noted Japanese digital media reviewer and critic, Reiji Asakura, provides his views on the next generation of DVD recorders and players. Asakura demonstrates how the Blu-ray disc and the HD DVD formats stack up against the standard DVD. The demonstration highlighted how the video enhancement feature in the next generation players will be a bonus for early adopters and could encourage videophiles to buy early models despite such concerns as copy protection and future upgrades. However, despite the intrinsic appeal of the next generation players, consumers are discouraged from making purchase in the meantime

Documentation of Surgical Specimens Using Digital Video Technology

Digital technology is commonly used for documentation of specimens in anatomic pathology and has been mainly limited to still photographs. Technologic innovations, such as digital video, provide additional, in some cases better, options for documentation. To demonstrate the applicability of digital video to the documentation of surgical specimens. A Canon Elura MC40 digital camcorder was used, and the unedited movies were transferred to a Macintosh PowerBook G4 computer. Both the camcorder and specimens were hand-held during filming. The movies were edited using the software iMovie. Annotations and histologic photographs may be easily incorporated into movies when editing, if desired. The finished movies are best viewed in computers which contain the free program QuickTime Player. Movies may also be incorporated onto DVDs, for viewing in standard DVD players or appropriately equipped computers. The final movies are on average 2 minutes in duration, with a file size between 2 and 400 megabytes, depending on the intended use. Because of file size, distribution is more practical via CD or DVD, but movies may be compressed for distribution through the Internet (e-mail, Web sites) or through internal hospital networks. Digital video is a practical, easy, and affordable methodology for specimen documentation, permitting a better 3-dimensional understanding of the specimens. Discussions with colleagues, student education, presentation at conferences, and other educational activities can be enhanced with the implementation of digital video technology.