Analytical Method Development Articles

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and validated for the estimation of telmisartan and hydrochlorothiazide simultaneously in combined dosage forms. The stationary phase used was precoated silica gel 60F254. The mobile phase used was a mixture of chloroform: methanol: toluene (2:5:5 v/v/v).

A new reversed-phase high performance liquid chromatography method was developed and validated for the simultaneous determination of losartan potassium and atenolol in tablets.

Two simple and sensitive visible spectrophotometric methods (A and B) have been developed for the quantitative estimation of nitazoxanide, in bulk drug and pharmaceutical dosage forms. Methods were based on the formation of reddish yellow coloured and green coloured chromogens, which were measured at 544 nm and 715 nm, respectively.

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and validated for the determination of cefuroxime axetil in dosage form. The stationary phase used was precoated silica gel 60F 254 . The mobile phase used was a mixture of chloroform:methanol:toluene (4:2:2 v/v). The detection of spot was carried out at 290 nm.

Valdecoxib is a nonsteroidal antiinflammatory drug, and it is listed in class 2 of biopharmaceutic classification of drugs. Valdecoxib is a poorly water-soluble and highly permeable drug. In the present study a new dissolution medium was developed, as there is no official dissolution medium available in the literature.

A simple, rapid, selective and sensitive reversed phase HPLC method was developed and validated for the determination of rebamipide from plasma. The drug was extracted with a mixture of chloroform and isopropyl alcohol. Rebamipide was measured in plasma using a validated HPLC method with UV detection at 280 nm.

Several gaps in current regulatory guidelines that govern the analytical method life cycle for the testing of biopharmaceuticals are identified. Strategic guidance on how to monitor and control the life cycle of an analytical test method is provided in this article. Analytical method transfer, analytical method component equivalency, and analytical method comparability protocols are discussed in light of risk-based strategies for validation extensions. The use of an analytical method maintenance program is suggested to control over time the predictable risk to patients and firm.

In the first part of this article1 we discussed the GAMP Good Practice Guide (GPG) for the Validation of Laboratory Computerized Systems.2 We looked at the advantages offered by the System Implementation Life Cycle (SILC) in contrast to the complexity of the system classification proposed in the GPG.

In this part I'll look at the risk assessment methodology, the new US Pharmacopeia (USP) general chapter <1058>,3 which is based upon the AAPS analytical equipment qualification white paper,4 and suggest a way forward to unite the qualification of equipment with the validation of the controlling laboratory computers.

Risk Assessment Methodology

Figure 1: GAMP GPG risk management process.

The design of pharmaceutical water systems has always been part science and part alchemy, and unfortunately, it is not likely to change in the near future. Daily rhetoric is rife with statements from informed and intelligent people alleging design requirements that do not actually exist.

The problem is that if you do not have documentation from a reliable source that supports or contradicts these statements, they are nearly impossible to refute. As a result, they are often incorporated into system design.

An isocratic HPLC method for the determination of phenol and nitrophenols (4-nitrophenol, 2-nitrophenol, 4,6-dinitro-o-cresol and 2,4-dinitrophenol) has been developed and validated using 2-chlorophenol as internal standard (IS) and a monolithic column in tap water samples. Prior to HPLC, the method requires solid-phase extraction (SPE) using polymeric Lichrolut EN cartridges. The method development involved the study of methanol and acetonitrile as organic modifiers, pH and flow-rate using a Chromolith RP-18e (150 mm × 4.6 mm I.D.) column. After comparing the performance of the separations obtained with both organic modifiers, the optimum separation of these compounds was achieved using 50 mM acetate buffer (pH 5.0)-acetonitrile (80:20, v/v) as mobile phase, 3 mL min-1 flow-rate and UV detection at maximum absorbance wavelength.