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DR ANTHONY MELVIN CRASTO Ph.D ( ICT, Mumbai) , INDIA 29Yrs Exp. in the feld of Organic Chemistry,Working for GLENMARK PHARMA at Navi Mumbai, INDIA. Serving chemists around the world. Helping them with websites on Chemistry.Million hits on google, world acclamation from industry, academia, drug authorities for websites, blogs and educational contribution
Deblina Roy Education: M. Sc. Kanpur University, Kanpur Current Position : TATA-CSIR OSDD Fellow, CDRI, Lucknow Email: pixiechem12@gmail.com Contact No : +91- 9475345275Research Area : CDRI-830 analogous synthesis and bio-evaluation
Vijeta Sah Education: M. Sc. Industrial Chemistry, Integral University, Lucknow Current Position : M.Sc. Trainee, CDRI, Lucknow Email: vijetasah@hotmail.com Contact No : +91-7408941827Research Area : ATP Synthase inhibitors as antitubercular agents
Conference Paper, International Conference WIN4Life, “Development of an advanced, innovative energy autonomous system for the treatment of brine from seawater desalination plants”, Tinos Island - Greece, 19/09/2013-21/09/2013
Conference Paper, International Conference WIN4Life, “Development of an advanced, innovative energy autonomous system for the treatment of brine from seawater desalination plants”, Tinos Island - Greece, 19/09/2013-21/09/2013
Conference Paper, 9ο ΠΑΝΕΛΛΗΝΙΟ ΕΠΙΣΤΗΜΟΝΙΚΟ ΣΥΝΕΔΡΙΟ ΧΗΜΙΚΗΣ ΜΗΧΑΝΙΚΗΣ: H Συμβολή της Χημικής Μηχανικής στην Αειφόρο Ανάπτυξη, 23-25 Μαϊου 2013, Αθήνα
May 2013
Projects
Θερμαλισμός και πιθανά καλυντικά προϊόντα - Thermalism and potential cosmetic products
Shaukat Ali, after a brief tenure at the University of Bridgeport had
joined the industry and worked in drug discovery and formulation
development. He has over 21 years of experience in the pharmaceutical
industries including 11 years at BASF, where he supports solubilization,
instant and modified release platforms, and APIs. His areas of
expertise include solid dispersions, liposome drug delivery, controlled
release, transdermal, and film development technologies.
He is a member of the editorial advisory boards of, American
Pharmaceutical reviews, Biopharma Asia, Contract Pharma, Drug Delivery
& Development, International Journal of Pharmaceutical
Investigation. He is also USP panel of experts for General
Chapters-Physical Analysis.
He received his Ph.D. in Chemistry from the City University of New York
and pursued his postdoctoral interest at the University of Minnesota
and Cornell University. He holds an adjunct faculty at the College of
Pharmacy of University of South Florida, Tampa. He has authored over 37
scientific articles and is co-inventor in 14 US patents.
Profile:
9 ½ years of experience with BASF in Pharma Ingredients & Services,
and about 10 years in Pharma industry in areas of drug discovery and
formulations development- solid and liquid oral, parenteral and
transdermal drug delivery technologies; expertise include (a)
solubilization by solid dispersion technologies (hot melt extrusion and
spray drying), and surfactant/lipid based emulsifying systems
(SEDDS/SMEDDS) (b) Quick dissolving films (c) design of gastroretentive
dosages, fluid bed granulation and controlled release and taste masking
coatings (d) lyophilization of parenteral formulations of poorly soluble
drugs (e) liposome drug delivery (f) regulatory and toxicology of
excipients and drug substances (g) analytical method development and
stability of dosages (h) process development and technology transfer for
clinical manufacturing (g) product’s internal monographs,
specifications, and CMC (i) managerial and entrepreneurship skills
complemented with good writing and communication abilities.
Organizational/Editorial Board Members:
American Pharmaceutical Review
Biopharma Asia UK
Contract Pharma
Drug Development and Delivery
International Journal of Pharmaceutical Investigation
Pharmaceutical Technology-Sourcing and Management
USP Expert Committee for General Chapters-Physical Analysis
Publications:
25 scientific articles and inventor/co-inventor in 14 US patents.
Academic:
Assistant Professor, Chemistry, University of Bridgeport, Connecticut (1993-1994)
Adjunct Visiting Faculty, College of Pharmacy, University of South Florida, Tampa, FL
Shaukat Ali has spent most of his professional life immersed in
lipids. After obtaining a PhD from the City University of New York in
lipid-chemistry and the post-doc from the University of Minnesota and
Cornell University in the physical biochemistry of lipids, he joined The
Liposome Company (Princeton, NJ), where he developed methods to reduce
drug toxicity by formulation in liposomes. Now, as Technical Support
Manager for Pharma Ingredients & Services at BASF, Ali promotes
BASF’s range of solubilizers and polymers for drug formulation,
including a selection of lipid-based drug delivery systems (LBDDSs).
“The bioavailability challenge is enormous,” Ali says. “There is no
one-size-fits-all approach, but it’s immensely satisfying to determine
the best formulation for a given molecule.”
The insolubility solution
Water-insoluble drugs usually dissolve in non-aqueous solvents, such
as ethanol, but will rapidly precipitate once that solution is
introduced to an aqueous medium, such as which is found in the stomach.
Oral delivery of these drugs, however, is not impossible. Ali says the
key, is to add other components or solubilizers to the non-aqueous drug
solution so when the solution is mixed with an aqueous medium, it
emulsifies to form tiny droplets that contain the drug and protect it
from exposure to water. Ideally, the droplets both prevent drug
precipitation and are readily absorbed. The magic ingredients that
promote emulsification are surfactants – molecules that have both
hydrophobic and hydrophilic regions, providing them with the convenient
ability to interact with both aqueous and non-aqueous media. “In
practice, this means that the solution of drug dissolved in the
non-aqueous solvent is distributed in the aqueous medium as a suspension
of microdroplets – a microemulsion – each bound by a layer of
surfactants in which the hydrophobic tails of the surfactant are
oriented to the interior of the micelle, and the hydrophilic headgroups
oriented to the exterior,” explains Ali.
Ali’s expertise lies in the precise choice of surfactants. Getting
the lipid based surfactants right is crucial because all surfactants
have different chemistries and every drug is unique. “It’s a case of
matching the correct surfactant to a given drug in the context of that
drug’s delivery requirements. The aim is to identify a surfactant which
can not only emulsify the drug as outlined above, but also ensure that
the drug remains encapsulated in the interior core during
gastro-intestinal transit, ultimately getting efficiently absorbed,”
says Ali.
Fat benefits
When it comes to micro-emulsion stability, Ali points out that drugs
need to remain in solution for extended periods – perhaps 3-5 hours – as
they move through the stomach to the absorptive region of the gut. A
drug may seem perfectly stable in a given LBDDS at first, but if it
starts precipitating after only 30 minutes then the formulation will
need to be redesigned. Furthermore, given the number and range of pH
changes to which the micro-emulsion droplets are exposed as they move
from stomach to intestine, it is essential the droplets remain stable
over a broad pH range. Ali says, “The ideal surfactant should be
non-ionic so it is resistant to pH changes.”
However, it is not just gastrointestinal pH fluctuations that can
cause problems – what about all the digestive enzymes? If enzymes
penetrate the micro-emulsion, they hydrolyze the surfactant fatty acid
chains, breaking down the ester linkage between the hydrophilic and
hydrophobic parts of the surfactant. Once that happens, the droplets
rapidly break down, exposing their drug cargo to aqueous media, which
results in drug precipitation. Resistance to digestion therefore is
essential; and it too depends on the surfactant’s fatty acid composition
of the micro-droplets. “The packing of fatty acid chains inside the
microemulsion is critical to the stability of the LBDDS formulation,”
says Ali. “One solution is to use an emulsifying agent (such as BASF’s
polyoxyl 40 hydrogenated castor oil (Kolliphor® RH40) that has a long,
saturated C18 fatty acid chain that goes deep into the droplet core.
These features will reinforce the micro-emulsion surface by making it
more tightly packed and promoting lateral interactions between fatty
acid chains like those found in lipid-cholesterol natural membrane.”
Such features keep out digestive enzymes, protecting surfactant
molecules from ester cleavage, whereas surfactants with short and
unsaturated fatty acid chains may provide looser packing and less
effective enzyme exclusion, making them less digestion-resistant.
To promote good drug absorption, emulsion droplet size is critical.
Droplet size is a function of emulsification rate, which in turn is,
again, dependent on the amount of surfactants in the formulation. Ali
says that BASF’s surfactants routinely provide droplets of 20-150 nm,
depending on the precise surfactant and formulation composition. “At
that size, they just disappear in an aqueous medium –the solution is
completely clear. Nanometre-sized droplets get absorbed very
efficiently, which is always a benefit in drug delivery,” he says.
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