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We report the development of a surface-enhanced Raman spectroscopy sensor chip by decorating gold nanoparticles (AuNPs) on ZnO nanorod (ZnO NR) arrays vertically grown on cellulose paper (C). We show that these chips can enhance the Raman signal by 1.25 × 107 with an excellent reproducibility of 92% clinical sensitivity and specificity. Our technology has the potential to be used for the early detection of prenatal diseases and can be adapted for point-of-care applications.

Introduction: Organic acids were examined from normal and Down syndrome pregnancies to identify possible differences between the amniotic fluid from fetuses with Down Syndrome compared with that of normal fetuses. Materials and Methods: Amniotic fluids were obtained from prior amniocenteses. Forty-one normal and 22 Down syndrome specimens were assayed using gas chromatography/mass spectrometry. Results and Discussion: 5-Hydroxycaproate, methylsuccinate, α-ketoglutarate, and adipate were significantly elevated in Down syndrome, suggesting riboflavin deficiency. Phenylpyruvate was also significantly elevated in fetuses with Down syndrome. Phenylpyruvate inhibits the metabolism of tetrahydrobiopterin, which is necessary for neurotransmitter metabolism. Elevated phenylpyruvate is consistent with previous research, suggesting a disturbance of tetrahydrobiopterin metabolism in Down syndrome. Conclusion: Organic acid markers for B2 deficiency are elevated in the amniotic fluid of fetuses with Down syndrome. Elevation of phenylpyruvate may impair neurotransmitter metabolism. Organic acid markers for B12 levels are not different between the Down syndrome and normal group.

Introduction: Some studies of children with Down syndrome have found mild abnormalities in the metabolism of pyridoxine (vitamin B6); therefore the present question is whether such abnormalities might also be present in the amniotic fluid of fetuses with Down syndrome. Materials and Methods: Archived specimens of amniotic fluid were obtained from chromosomally normal and from fetuses with Down syndrome. Gas chromatography/mass spectrometry quantitized B-related metabolites, including oxalate, xanthurenate, kynurenine and 4-pyridoxic acid. Results: Oxalate, a marker of pyridoxine deficiency, was elevated in the amniotic fluid of fetuses with Down syndrome. This result was statistically significant. The other marker results were not statistically significant. Conclusion: A marker of pyridoxine deficiency, oxalate is elevated in the amniotic fluid of fetuses with Down syndrome. These results in amniotic fluid are consistent with previous studies done in the urine of young children.

The effect of Millipore filtration on four methods of bilirubin determination in amniotic fluid was investigated. Millipore filtration is unacceptable as a method of amniotic fluid clarification when the methods of Ovenstone and Connon6 or Fleming and Woolf5 are used. Results obtained from the methods of Liley1 and Freda2 were not much affected by this type of filtration.

Eighty-one human amniotic fluid samples of assessment of pulmonary maturity in utero have been studied by means of the capillary method, a simple and rapid test that correlates with the shake test and L/S ratio. With the advancement of gestational age the flow rate of amniotic fluid decreases on cellulose filter paper (Whatman) in the capillary pasteur pipette. Retention time for 20 microliter amniotic fluid of 74 +/- seconds correlates well with the positive shake test and with L/S ratio of 2.0 or greater in normal human pregnancies.