Pure analytical standards are key components in the successful development of accurate analytical methods. When such compounds are unavailable commercially, a laboratory synthesis activity can provide such materials for use in method development. An example of such an approach is the synthesis of ethyl ethers of chlorinated phenols and ethyl esters of several phenoxy herbicides. Individual synthesis steps and the characterization of such materials are described. The use of such analytical standards in method development is vital for defining method characteristics. In addition, such materials are helpful in diagnosing chromatographic and mass spectral problems in the course of this work. Key mass spectral information including parent and daughter scans obtained from these analytical standards by using tandem mass spectrometry provide the basis for a new analytical method with increased sensitivity and specificity.

Chemical Phenomena↗

PubMedDate not supplied

Childhood thrombocytopenic purpura--review and a case report.

Childhood idiopathic thrombocytopenic purpura is a rare condition seen in children. A case of a 10 year old female child is reported. Bleeding from the gingiva and petechiae on the tongue were observed. The blood picture was normocytic normochromic with neutrophilia and thrombocytopenia. Bone marrow study was suggestive of marrow changes in idiopathic thrombocytopenic purpura. Dental extractions were postponed. Recognition of the disease by the dental profession is stressed.

Bone Marrow Examination↗

PubMedDate not supplied

A comparison of bitewing radiography and fibreoptic illumination as adjuncts to the clinical identification of approximal caries in primary and permanent molars.

A clinical study was conducted on 150 approximal surfaces which were positive for caries by fibreoptic transillumination (FOTI), and these approximal surfaces were examined with bitewing radiography. Of these 54.7% and 41.3% were diagnosable through bitewing radiography and clinical examination respectively. And it was clearly understood that FOTI was a reliable method in detecting approximal carious lesions.

Dental Caries↗