Using a CCD Camera Imaging System as a Recording Device to Quantify Human DNA by Slot Blot Hybridization

Abstract

Slot blot hybridization of membrane-immobilized, single-stranded human DNA with the higher primate-specific alphoid probe D17Z1 is routinely used in forensic science to estimate the amount of DNA in biological samples. Typically, a chemiluminescent signal captured on film records the hybridization, and the quantity of the signal is related to the amount of immobilized DNA. Digital imaging using a cooled CCD camera offers an alternate non-film-based method for image acquisition with comparable sensitivity of detection, a greater dynamic range, enhanced capability of data interpretation, and often faster results than film. In addition, the data support the premise that more accurate and precise human DNA quantification should be obtained by not assuming a linear response of signal to known standards. Instead, quantity should be estimated using a second-order standard curve (R2 = 0.999). Finally, a CCD camera imaging system offers versatility for image capture of different signal sources and analysis of samples on a variety of support media.

Cytokines as potential biomarkers of liver toxicity induced by Dioscorea bulbifera L.

“…The other 9 cytokines were not changed when measured by ELISA, which may be due to the limitations of the cytokine antibody array. There is already a report demonstrating that a linear response between the chemiluminescent signal and quantity may not always exist, which may lead to the false results shown in the cytokine antibody array (23), so further verification experiments such as ELISA are necessary. CD30L is the ligand for CD30, which represents the newest member of the tumor necrosis factor receptor (TNF-R) family (24).…”

Selective Desensitization of Growth Factor Signaling by Cell Adhesion to Fibronectin

“…The methodology is based on digital imaging using a cooled CCD camera that has a theoretically wider linear dynamic range than standard film-based imaging (17,18). However, even when signals are within the detection limit of the imaging system, data points do not always conform to the expected linear trend (supplemental Fig.…”

“…One prominent point of cross-talk between adhesion and growth factors involves the serine/threonine kinase, extracellular signal-regulated kinase (Erk). 2 Several reports have shown that growth factor-mediated Erk signaling is enhanced among cells adhered to extracellular matrix (ECM) proteins (2,(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). In fact, this adhesion-mediated enhancement of Erk signaling plays a crucial role in cell cycle regulation.…”

Further Development and Validation of DNA-Based Methods for Species of Origin Determination and Human DNA Quantitation in Forensic Casework Specimens

“…The standard curve is then used to calculate the DNA quantity in specimens from chemiluminescence intensities. This method is more objective than the analysis based on visual evaluation alone (5). QuantiBlot is a time-consuming and tedious procedure.…”