Modified automated titration system equipped with ultrasound for the assay of absorbing gel materials in diapers

✍ Scribed by Kyoko Ida; Shunji Ishigami; Noriko Nakagawa

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 155 KB
• Volume: 10
• Category: Article
• ISSN: 0895-7533
• DOI: 10.1002/(sici)1098-2728(1998)10:3<125::aid-lra2>3.0.co;2-6

✦ Synopsis

The current system for quantitative determination of absorbing gel materials (AGMs) in diapers utilizes air bubbling in the extraction procedure followed by acid-based titration. However, two issues have arisen: One is a corrosion problem on stainless steel frames due to acid vapor coming from the extraction bath. The other is an increased number of samples beyond the capacity of the current system. To overcome these situations, we modified the system. We covered the bath during the extraction to prevent acid vapor diffusion and replaced air bubbling with ultrasound to reduce the extraction time, thus increasing sample-handling capacity.

The system consists of a Zymate XP robot, three sample racks (36 pads per rack), a Mettler titrator, an extraction bath, an Ultrasonic homogenizer, three pumps, two balances, and a waste container. It gives more than 98% recovery. The extraction using ultrasound requires only 3 minutes, while the current system requires 8 minutes. One extraction bath in this new system proved superior or at least equal to three baths using air bubbling. In conclusion, the new system enhanced our capability of AGM assay and solved the corrosion problem.