Dipalmitoyl-phosphatidylglycerol

DSPC distearoyl phosphatidylcholine DPPG dipalmitoyl phosphatidylglycerol MI mechanical index... 

With respect to safety and the use of phospholipids, no NDA-supporting chronic inhalation studies have been conducted except for those found in commercial pulmonary surfactants. These studies presumably will have involved intratracheal instillation and not aerosolization, since the primary indication is respiratory distress syndrome of the newborn. Nevertheless, the fact that these products are available suggests that synthetic versions of natural lipids such as dipalmitoyl phosphatidylcholine (DPPC) and dipalmitoyl phosphatidylglycerol (DPPG) are likely to be well tolerated. This assumption has been supported from subchronic aerosol studies in mice [60] and acute single-dose aerosol studies in man, the latter involving soy-derived phosphatidylcholines [61]. 

Fig. 2.5. X-ray long spacings at 20 C as a function of water/lipid weight ratio, (l-c)/c. Derived from the low-angle diffraction of dipalmitoyl phosphatidylglycerol multibilayers at pH 8.0, 1.5 M KCl/50 mM Tris (o—o) and pH 1.5, 1.5 M KCl/HCl ----------------A ) (Watts et al., 1981).

The pH titration of the transition temperature of dimyristoyl and dipalmitoyl phosphatidylglycerol bilayers is given in Fig. 2.6. 

Fig. 2.6. Phase transition temperatures of (a) dimyristoyl and (b) dipalmitoyl phosphatidylglycerol bilayers (1.4 mM) in 0.1 M KCl as a function of pH. Open circles, heating closed circles, cooling (Watts et al., 1978).

Figure 1.90 Dipalmitoyl L-oc-phosphatidylglycerol (DPPG) layer to illustrate crystal packing in 2D-lamellar layers. In lipid assembly terms this can be considered secondary/tertiary structure formation.

L-o-1,2-Dipalmitoyl-sn-phosphatidylglycerol sodium salt. See Sodium 1,2-dipalmitoyl-sn-glycero (3) phosphatidylcholine Dipalmityl adipate. See Dicetyl adipate Dipalmitylamine. See Dipalmitamine DIPAN. See Diphenylacetonitrile Dipanol. See dl-Limonene m-DIPB. See 1,3-Diisopropyl benzene p-DIPB. See 1,4-Diisopropyl benzene diPE. See Dipentaerythritol Di (PEG-9 nonyl phenyl ether) citrate Di (PEG 450 nonyl phenyl ether) citrate. See Dinonoxynol-9 citrate... 

Synonyms L-a-1,2-Dipalmitoyl-sn-phosphatidylglycerol sodium salt Uses Emulsifier, solubilizer for dermatology and cosmetics, mfg. of liposomes and mixed micelles for pharmaceuticals Trade Name Synonyms Phospholipon PG Na t[Am. Lecithin... 

The phosphatidylglycerols (PC), but no other lipid classes, from the chilling-sensitive plants, contain a large proportion of saturated molecular species, 1,2-dipalmitoyl-PG and sn-1-palmitoyl-2-(trans-3)hexadecenoy1-PG, which undergo a thermotrophic phase transition at the room temperature range or above (Murata et al. 1982 Murata 1983 Murata and Yamaya 1984). 

Fig. 2.7. Phase transition temperatures of dimyristoyl (DMPG) and dipalmitoyl (DPPG) phosphatidylglycerol as a function of the bulk NaCl concentration, c, and the headgroup ionization. PG° 0.1 N HCl pH 1.08 PG triethanolamine -HCl/NaOH pH 7.0 (Cevc et al., 1980).

Dipalmitoyllecithin. See 1,2-DipalmHoyl-sn-glycero(3) phosphatidylcholine L-a-1,2-Dipalmitoyl-sn-phosphatidylglycerol sodium salt. See Sodium 1,2-dipalmitoyl-sn-glycero (3) phosphatidylcholine Dipanol. See dl-Limonene... 

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