Versatile Molecular Silver Ink Platform for Printed Flexible Electronics.

A silver molecular ink platform formulated for screen, inkjet, and aerosol jet printing is presented. A simple formulation comprising silver neodecanoate, ethyl cellulose, and solvent provides improved performance versus that of established inks, yet with improved economics. Thin, screen-printed traces with exceptional electrical (<10 mΩ/□/mil or 12 µΩ·cm) and mechanical properties are achieved following thermal or photonic sintering, the latter having never been demonstrated for silver-salt-based inks. Low surface roughness, submicron thicknesses, and line widths as narrow as 41 µm outperform commercial ink benchmarks based on flakes or nanoparticles. These traces are mechanically robust to flexing and creasing (less than 10% change in resistance) and bind strongly to epoxy-based adhesives. Thin traces are remarkably conformal, enabling fully printed metal-insulator-metal band-pass filters. The versatility of the molecular ink platform enables an aerosol jet-compatible ink that yields conductive features on glass with 2× bulk resistivity and strong adhesion to various plastic substrates. An inkjet formulation is also used to print top source/drain contacts and demonstrate printed high-mobility thin film transistors (TFTs) based on semiconducting single-walled carbon nanotubes. TFTs with mobility values of ∼25 cm2 V-1 s-1 and current on/off ratios >104 were obtained, performance similar to that of evaporated metal contacts in analogous devices.

Seasonal variations do not affect the superiority of fecal immunochemical tests over guaiac tests for colorectal cancer screening.

The aim of this study was to compare the seasonal variation in performance of a faecal immunochemical test for haemoglobin (FIT) and a guaiac test (gFOBT) for colorectal cancer screening. From June 2009 to May 2011, 18,290 screening participants (50-74 years old) performed OC-SENSOR quantitative FIT (1 sample) and Hemoccult II gFOBT (3 stool samples with 2 spots/sample). Referral for colonoscopy required a minimum of one positive spot (gFOBT), or a positive FIT [cut-off 150 ng haemoglobin/mL buffer (i.e. 30 µg haemoglobin/g feces)]. The performance of tests for detection of advanced neoplasia was compared according to seasons using Receiver Operating Characteristics (ROC) curves, at various FIT cut-off values. The positivity rate of FIT was significantly lower in the summer compared with other seasons (2.3% versus 3.0%, p = 0.03), whilst the positivity rate of gFOBT increased in the autumn (1.8% versus 1.5%, p = 0.11). FIT was clinically more effective than gFOBT over the four season-specific ROC curves. At the cut-off concentration used in the study, the season-specific FIT/gFOBT ratios for true positive rates were: 2.8 (Autumn), 2.5 (Winter), 3.0 (Spring), 3.7 (Summer), and for false positive rates: 1.2 (Autumn), 1.5 (Winter), 1.8 (Spring), 0.9 (Summer). Therefore, in this study with this cut-off concentration and in spite of lower positivity rate in summer, the seasonal variations of performance of OC-SENSOR FIT led to improved gain in specificity in the summer, without a decrease in gain in sensitivity compared with gFOBT.

A population-based comparison of immunochemical fecal occult blood tests for colorectal cancer screening.

BACKGROUND & AIMS: Quantitative fecal immunochemical tests (FITs) identify individuals with colorectal cancer with greater levels of accuracy than guaiac tests. We compared the performances of 2 FITs in a population undergoing screening for colorectal cancer. METHODS: We collected fecal samples from 19,797 individuals in France (age, 50-74 y) who participated in a colorectal cancer screening program, from June 2009 through May 2011. Samples were analyzed using the Magstream (Fujirebio Inc, Tokyo, Japan) and OC Sensor (Eiken Chemical Co, Tokyo, Japan) (2 samples each) FITs, as well as the Hemoccult II guaiac test (SKD, Villepinte, France) (3 samples each). Colonoscopies were performed for patients with positive results from all 3 tests. The cut-off values for levels of hemoglobin in buffer and stools were 55 ng/mL and 180 µg/g for the Magstream and 150 ng/mL and 30 µg/g for the OC Sensor, respectively. Results from the FITs were compared with those from the guaiac test for cut-off values for stool samples, positivity rates, and the receiver operating characteristic curve values. The numbers needed to screen and the numbers needed to scope to detect an advanced neoplasia (cancer, adenoma ≥10 mm, or high-grade dysplasia) were calculated. RESULTS: A positive test result was found in 1224 participants (6.2%); 1075 (87.8%) underwent a colonoscopy examination. Of these, 334 were found to have advanced neoplasia. Considering the cut-off values associated with the positivity rate of Hemoccult II (1.6%), the numbers needed to screen were 239 for Hemoccult II, 166 for a 1-sample Magstream FIT, and 129 for a 1-sample OC Sensor FIT; the numbers needed to scope were 3.3, 2.3, and 1.8, respectively. For the same false-positive rate as Hemoccult II (0.98%), the true-positive rates for Magstream and OC Sensor FITs were 0.65% and 0.90% respectively, compared with 0.42% for Hemoccult II. The OC Sensor FIT had a greater area under the receiver operating characteristic curve value than the Magstream FIT. CONCLUSIONS: Based on results from a large, population-based study, the OC Sensor FIT identifies patients with colorectal cancer with greater accuracy than the Magstream FIT. ClinicalTrials.gov number: NCT01251666.