Abstract An ultrasound pretreatment was used to increase anthocyanins content in blackberry juice. Whole fruits were inserted into a glass vessel without contact with any solvent, sonicated in an ultrasonic bath, and then pressed with a manual juicer. The experimental design showed that 7 min at 65% of ultrasound amplitude increased the anthocyanin content in juices from 31 to 56% for BRS Xingu, Guarani, and Xavante cultivars. Two major anthocyanins, cyanidin-3-glucoside and cyanidin-3-rutinoside were found in higher concentrations for sonicated fruits. Therefore, ultrasonic pretreatment of whole fruits increased the anthocyanins in blackberry juices using a simple, fast, and green approach.

The use of paper devices in chemical analysis has been increased due to their low cost, high surface area, portability, and biodegradability. A novel use of paper devices is proposed using thermal infrared enthalpimetry (TIE) for a rapid, green, and high throughput determination of wine acidities. The determination of total, fixed, and volatile acidities in red, white, and sparkling wine was carried out, and the results were compared with AOAC titration method. A multichannel pipette was used for reagent addition and an infrared camera for the temperature monitoring. The pipetting and temperature measurement conditions presented direct influence in the deviations among the measurements. The results obtained by TIE presented an agreement between 96 and 104% with the reference method (AOAC 962.12), for all samples. A high sample throughput was achieved reaching 480 samples h-1 for total acidity. A significant reduction in sample volume and reagent consumption was also obtained, with energy consumption up to 60 times lower in relation to the AOAC method. The association of TIE with a paper device provided a rapid, reliable and green method for the determination of acidities of wines.

Content uniformity (CU) is a parameter used to ensure the uniformity of the amount of active substances in pharmaceutical preparations. It is often evaluated in the quality control of pharmaceutical dosage forms, and a novel method was proposed for CU determination using thermal infrared enthalpimetry (TIE). Captopril tablets were dissolved in 24-well microplates and the heat released from the reaction of captopril and I2 was monitored with an infrared camera. Some experimental parameters were adjusted, as captopril/I2 ratio, stirring speed and dispensing rate, and the most suitable conditions were 1.00:1.00 (v/v), 250 rpm and 0.57 mL s-1, respectively. Interferences from tablet adjuvants (e.g., starch, cellulose and lactose) were not observed. The results obtained by TIE did not differ statistically (Student’s t-test, p > 0.05) from those from official method (UV spectrophotometry) described in pharmacopeia. The TIE method required 31 and 12 times less reagent and time, respectively. Therefore, the proposed method was suitable for routine analysis and agrees with the requirements of green analytical chemistry.