A computer controlled pH meter was developed using simple op-amp circuits. Analog to digital converter (ADC) card was used to acquire the output potential from the op-amp. S9ftware based signal averaging helped in reduction of electrical noise. The instrument was calibrated against pH and ammonia selective electrodes where it followed Nemstian behaviour and was l\Sed in the development of a sim...

Objectives/Goals The purpose of this project was to study the growth of the bacteria Escherichia coli DH5a under a variety of different pH and temperature, in order to discover and approximate the optimal value at which the cell was able to increase in size and divide the quickest. Methods/Materials Material used for this experiment included Eschericha coli DH5a, flasks, cuvettes, test tubes, a...

A method has been developed for determination of sodium concentration (activity) in urine using a glass electrode designed to be especially sensitive to sodium ion activity. The urine is diluted 2:20 with Tris buffer (pH 8.0) and sodium activity measured by dipping a sodium electrode and calomel reference electrode in the diluted specimen and obtaining a millivolt reading with a sensitive pH me...

Aim—To evaluate the reliability of dipstick measurements of urine specific gravity (U-SG). Methods—Fresh urine specimens were tested for urine pH and osmolality (U-pH, U-Osm) by a pH meter and an osmometer, and for U-SG by three diVerent methods (refractometry, automatic readout of a dipstick (Clinitek-50), and (visual) change of colour of the dipstick). Results—The correlations between the vis...

pH is frequently measured in laboratories, but to have confidence in the results it is necessary to know that it was measured properly. For an electrode to give accurate results it must be treated well and calibrated correctly. In this paper, an automated system for pH measurement is described; the system uses the operational pH scale and calibrates using two or three buffer solutions, taking p...

Consumption of liquid oral medicine by frequently ill children, significantly increases the risk of tooth demineralization. In this study a survey was conducted wherein the pediatricians, pharmacist and medical representatives of Bhopal city were enquired about the most commonly prescribed liquid oral medicines for children. The four categories of medicines reported were: antipyretics/analgesic...

More than 30 years ago, Nozaki and Tanford reported that the pK values for several amino acids and simple substances in 6 M guanidinium chloride differed little from the corresponding values in low salt (Nozaki, Y., and C. Tanford. 1967. J. Am. Chem. Soc. 89:736-742). This puzzling and counter-intuitive result hinders attempts to understand and predict the proton uptake/release behavior of prot...

BACKGROUND The clinical symptoms of facial and truncal acne differ. Skin surface acidity (pH), which is affected by sebum secretions, reflects the different clinical characteristics of the face and trunk. However, no studies have been conducted on truncal sebum production and skin pH. OBJECTIVE We evaluated the differences and relationship between pH values of the face and trunk. We also eval...

OBJECTIVES There are few studies on crystalluria in the developing countries. The aim of the present study was carrying out a first study in Morocco on the frequency and the chemical nature of the crystalluria according to the sex and the age of human individuals living in the Tadla Azilal moroccan area. METHOD 200 samples resulting from the morning urines of morning fasting individuals of th...