Synthesis and response of new microsensor coatings-II Acridinium betaines and anionic surfactants.

Four acridinium betaines and two ionic surfactants were synthesized, and evaluated as chemical microsensor coatings by exposure to vapors of chloroethyl ethyl sulfide (CEES) and dimethyl methylphosphonate (DMMP). Two of the acridinium betaines showed selective and reversible responses (of 9.8 and 6.8 kHz) as SAW (surface acoustic wave) coatings in the detection of CEES vapor: there appears to be a connection between the long alkyl chain (C-12 and C-14) in the acridinium molecules and the response. Response times were generally less than 30 sec but desorption was significantly slower. The ionic surfactant coatings show small SAW changes (> 0.5 kHz) in response to DMMP vapor, and somewhat greater responses (20- and 68-fold), as chemiresistors, to CEES vapor. In each case the response occurred within 3 min, with return nearly to baseline levels within 6 min of cessation of exposure to the vapor. The responses were reproducible within +/- 5%.

Synthesis of new microsensor coatings and their response to vapors-III Arylphosphonic acids, salts and esters.

Phosphonic acids, phosphonate esters and cyclohexylammonium phosphonates, spray-coated onto surface acoustic wave (SAW) devices, were exposed to vapors of chloroethyl ethyl sulfide (CEES), dimethyl methylphosphonate (DMMP), and water. Changes in the resonance frequency of the device or the resistance of the coating were collected by computer-controlled data acquisition. Two of the esters showed major reversible and selective response to CEES, and one of the acids showed similar behavior with DMMP.

Pigmented villonodular synovitis in the hand.

The related disorders of pigmented villonodular synovitis and pigmented villonodular tenosynovitis have very different clinical presentations. The synovial form occurs most frequently in the knee although other lower extremity joints including the hip, ankle and subtalar joints can be involved. Rarely, the shoulder, elbow and wrist have been the joint of origin. In contrast, the tenosynovial form is one of the most common masses in the hand and is found very much less frequently elsewhere. This report documents the synovial origin of four cases involving the small joints of the hands.