(AB) PKU Test Agar 500g

Phenylketonuria (PKU) results from an inborn error of phenylalanine metabolism. In this disease, phenylalanine hydroxylase deficiency causes accumulation of the amino acid phenylalanine with subsequent neurological damage. Detecting and managing PKU is possible by testing infants for abnormal levels of phenylalanine or its metabolites. In the PKU test procedure, PKU Test Agar is inoculated with a suspension of Bacillus subtilis ATCC 6633. The presence of phenylalanine allows the organism to grow. Filter paper saturated with infant blood and control disks impregnated with known concentrations of L-phenylalanine are applied to the surface of the medium. After incubation, the zones of the test disk are compared to those of the control disks. PKU Test Agar is used with Bacto Subtilis Spore Suspension No. 2 to give an estimated level of phenylalanine in the blood. (Alpha Biosciences # P16-128-500gm)

Use: PKU Test Agar is used with Bacto Subtilis Spore Suspension No. 2 to give an estimated level of phenylalanine in the blood.

Description: Phenylketonuria (PKU) results from an inborn error of phenylalanine metabolism. In this disease, phenylalanine hydroxylase deficiency causes accumulation of the amino acid phenylalanine with subsequent neurological damage. Detecting and managing PKU is possible by testing infants for abnormal levels of phenylalanine or its metabolites. In the PKU test procedure, PKU Test Agar is inoculated with a suspension of Bacillus subtilis ATCC 6633. The presence of phenylalanine allows the organism to grow. Filter paper saturated with infant blood and control disks impregnated with known concentrations of L-phenylalanine are applied to the surface of the medium. After incubation, the zones of the test disk are compared to those of the control disks.

Formula* per Liter:

• L-Glutamic Acid ......................... 0.5g
• DL-Alanine ....................................…0.5g
• Asparagine ...................……….. 0.5g
• Dextrose ……………. ................... 10.0g
• Dipotassium Phosphate ......... 15.0g
• Monopotassium Phosphate ........... 5.0g
• Ammonium Chloride …...….…. 2.5g
• Ammonium Nitrate ......................….0.5g
• Magnesium Sulfate …………..0.05g
• Sodium Sulfate ……………........…0.5g
• Ferric Chloride ………………0.005g
• Manganese Chloride ….....…….0.005g
• Calcium Chloride …....…….0.0025g
• Thienylalanine………...........…..0.0033g
• Agar ………………...........……15.0g

Final pH: 7.0 ± 0.2 at 25.0°C

* Grams per liter may be adj. or formula supplemented to obtain desired performance

Preparation: Mix 8.5g of medium in 100ml of purified water until evenly dispersed. Heat with repeated stirring and boil for one minute to dissolve completely. Dispense 5ml amounts into tubes. Add standard or test samples. Adjust tube volume to 10ml with purified water. Autoclave at 121.0°C for 15 minutes.

Quality Control Specifications:

1. The powder is homogeneous, lumpy, and light beige.
2. The prepared media is light amber, clear, and may have a slight precipitate.
3. Expected cultural response after 12-16 hours at 35.0°C; increase in zone size comparable to the increasing concentration of phenylalanine in the standard disks.

Storage: Store the sealed bottle containing the dehydrated medium at 2 to 30.0°C. Once opened and recapped, place the container in a low humidity environment at the same storage temperature. Protect it from moisture and light. The dehydrated medium should be discarded if it is not free flowing or if the color has changed from the original light beige color.